Assessment of the pseudo-tracking approach for the calculation of material acceleration and pressure fields from time-resolved PIV: part I. Error propagation

NASA Astrophysics Data System (ADS)

van Gent, P. L.; Schrijer, F. F. J.; van Oudheusden, B. W.

2018-04-01

Pseudo-tracking refers to the construction of imaginary particle paths from PIV velocity fields and the subsequent estimation of the particle (material) acceleration. In view of the variety of existing and possible alternative ways to perform the pseudo-tracking method, it is not straightforward to select a suitable combination of numerical procedures for its implementation. To address this situation, this paper extends the theoretical framework for the approach. The developed theory is verified by applying various implementations of pseudo-tracking to a simulated PIV experiment. The findings of the investigations allow us to formulate the following insights and practical recommendations: (1) the velocity errors along the imaginary particle track are primarily a function of velocity measurement errors and spatial velocity gradients; (2) the particle path may best be calculated with second-order accurate numerical procedures while ensuring that the CFL condition is met; (3) least-square fitting of a first-order polynomial is a suitable method to estimate the material acceleration from the track; and (4) a suitable track length may be selected on the basis of the variation in material acceleration with track length.

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

Hoof accelerations and ground reaction forces of Thoroughbred racehorses measured on dirt, synthetic, and turf track surfaces.

PubMed

Setterbo, Jacob J; Garcia, Tanya C; Campbell, Ian P; Reese, Jennifer L; Morgan, Jessica M; Kim, Sun Y; Hubbard, Mont; Stover, Susan M

2009-10-01

To compare hoof acceleration and ground reaction force (GRF) data among dirt, synthetic, and turf surfaces in Thoroughbred racehorses. 3 healthy Thoroughbred racehorses. Forelimb hoof accelerations and GRFs were measured with an accelerometer and a dynamometric horseshoe during trot and canter on dirt, synthetic, and turf track surfaces at a racecourse. Maxima, minima, temporal components, and a measure of vibration were extracted from the data. Acceleration and GRF variables were compared statistically among surfaces. The synthetic surface often had the lowest peak accelerations, mean vibration, and peak GRFs. Peak acceleration during hoof landing was significantly smaller for the synthetic surface (mean + or - SE, 28.5g + or - 2.9g) than for the turf surface (42.9g + or - 3.8g). Hoof vibrations during hoof landing for the synthetic surface were < 70% of those for the dirt and turf surfaces. Peak GRF for the synthetic surface (11.5 + or - 0.4 N/kg) was 83% and 71% of those for the dirt (13.8 + or - 0.3 N/kg) and turf surfaces (16.1 + or - 0.7 N/kg), respectively. The relatively low hoof accelerations, vibrations, and peak GRFs associated with the synthetic surface evaluated in the present study indicated that synthetic surfaces have potential for injury reduction in Thoroughbred racehorses. However, because of the unique material properties and different nature of individual dirt, synthetic, and turf racetrack surfaces, extending the results of this study to encompass all track surfaces should be done with caution.

Soft tissue regeneration using leukocyte-platelet rich fibrin after exeresis of hyperplastic gingival lesions: two case reports.

PubMed

di Lauro, A E; Abbate, D; Dell'Angelo, B; Iannaccone, G A; Scotto, F; Sammartino, G

2015-11-02

Leukocyte-platelet rich fibrin belongs to a second generation of platelet concentrates that does not need biochemical blood manipulation. It is used for tissue healing and regeneration in periodontal and oral-maxillofacial surgery. We report two cases of hyperplastic gingival lesions treated by exeresis and application of leukocyte-platelet rich fibrin membranes in order to improve and accelerate tissue healing. Two patients (a 78-year-old Caucasian woman and a 30-year-old Caucasian man) were treated for hyperplastic gingival lesions. They underwent to exeresis of lesions and application of leukocyte-platelet rich fibrin membranes. Tissue healing was clinically evaluated after 1, 3, 7, 14 and 30 postoperative days. No recurrences were observed after 2 years of semi-annual follow up. We obtained rapid and good healing of soft tissues probably due to the elevated content of leukocytes, platelets and growth factors in the leukocyte-platelet rich fibrin. Based on our results we suggest the use of leukocyte-platelet rich fibrin to cover wounds after exeresis of oral neoformations such as hyperplastic gingival lesions.

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.

Correlation of leukocyte adhesiveness, adhesion molecule expression and leukocyte-induced contraction following balloon angioplasty

PubMed Central

Kennedy, Simon; McPhaden, Allan R; Wadsworth, Roger M; Wainwright, Cherry L

2000-01-01

The aim of this study was to examine the changes in leukocyte adhesion and leukocyte-induced contraction in balloon-injured rabbit subclavian artery and to correlate these changes with vessel morphology and expression of adhesion molecules on the injured arteries.Rabbits were anaesthetized and their left subclavian arteries were injured by balloon inflation and withdrawal followed by sacrifice at 2, 24, 48 h or 8 days after injury. The left and right subclavian arteries were removed and leukocytes were isolated from autologous rabbit blood. Leukocyte-induced contraction was measured in 5-HT precontracted artery rings and leukocyte adhesion was measured using 51Cr-labelled leukocytes. Immunocytochemistry using paraffin-embedded tissue was employed to detect changes in the expression of adhesion molecules on injured arteries.Autologous leukocytes caused a contraction of rabbit subclavian artery rings, which was prevented by L-NAME (10−3 M). Balloon-induced injury abolished the contractile response to leukocytes, which correlated with loss of carbachol-induced relaxationBalloon injury markedly enhanced the adhesiveness of the subclavian artery for leukocytes, most notably at 24 and 48 h after injury (1.7 and 1.8 fold respectively). Increased leukocyte adhesion at these two time points correlated with an upregulation of E-selectin, P-selectin and VCAM-1 expression on the remaining endothelium of the injured artery.Vessel morphology revealed that balloon inflation had induced an infiltration of inflammatory cells into the vessel wall, the greatest increase being seen at 24 h after injury.It is concluded that an increase in the expression of E-selectin, P-selectin and VCAM-1 following balloon-induced injury leads to enhanced leukocyte adhesion and migration into the injured vessel. PMID:10781003

[Exceptional production of leukocyte-free erythrocyte concentrates using filtration with the BPF 4 BBS leukocyte filter].

PubMed

Zimmermann, B; Hillringhaus, I; Diekamp, U

1994-01-01

Leukocyte depletion prevents some undesirable effects of red cell transfusions. We evaluated the blood filter system BPF 4 BBS (PALL) by filtering 26 units of buffy coat-free red cell concentrates, prepared from 500 ml of whole blood and suspended in SAG-M-additive solution, over 8 min within 48 h after donation at room temperature. Filtration reduced the leukocyte content by more than 99.99% in 25 of the 26 units examined. In 20 instances, no leukocyte was found in the Nageotte counting chamber (2 x 50 microliters) corresponding to a total leukocyte count below 2.38 x 10(4). In 5 instances a single leukocyte was seen, corresponding to a total leukocyte count of (2.35 +/- 0.01) x 10(4). One unit contained 2.93 x 10(5) leukocytes after filtration, corresponding to a 99.98% leukocyte reduction. Red cell recovery was 92.5 +/- 3.8%. This system is well suited for routine use.

Visualization of complex DNA damage along accelerated ions tracks

NASA Astrophysics Data System (ADS)

Kulikova, Elena; Boreyko, Alla; Bulanova, Tatiana; Ježková, Lucie; Zadneprianetc, Mariia; Smirnova, Elena

2018-04-01

The most deleterious DNA lesions induced by ionizing radiation are clustered DNA double-strand breaks (DSB). Clustered or complex DNA damage is a combination of a few simple lesions (single-strand breaks, base damage etc.) within one or two DNA helix turns. It is known that yield of complex DNA lesions increases with increasing linear energy transfer (LET) of radiation. For investigation of the induction and repair of complex DNA lesions, human fibroblasts were irradiated with high-LET 15N ions (LET = 183.3 keV/μm, E = 13MeV/n) and low-LET 60Co γ-rays (LET ≈ 0.3 keV/μm) radiation. DNA DSBs (γH2AX and 53BP1) and base damage (OGG1) markers were visualized by immunofluorecence staining and high-resolution microscopy. The obtained results showed slower repair kinetics of induced DSBs in cells irradiated with accelerated ions compared to 60Co γ-rays, indicating induction of more complex DNA damage. Confirming previous assumptions, detailed 3D analysis of γH2AX/53BP1 foci in 15N ions tracks revealed more complicated structure of the foci in contrast to γ-rays. It was shown that proteins 53BP1 and OGG1 involved in repair of DNA DSBs and modified bases, respectively, were colocalized in tracks of 15N ions and thus represented clustered DNA DSBs.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 positivemore » 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.« less

Leukocyte telomere length in Hispanic schizophrenia patients under treatment with olanzapine.

PubMed

Monroy-Jaramillo, Nancy; Rodríguez-Agudelo, Yaneth; Aviña-Cervantes, Luis Carlos; Roberts, David L; Velligan, Dawn I; Walss-Bass, Consuelo

2017-07-01

Different lines of evidence indicate that patients with schizophrenia (SZ) exhibit accelerated aging. Leukocyte telomere length (TL), an aging marker, is associated with age-related and chronic pathologies, including schizophrenia. We analyzed leukocyte TL in 170 SZ patients of Hispanic ancestry grouped based on antipsychotic treatment, compared to 126 matched controls. The group under treatment with atypical antipsychotics was further subdivided according to the risk of medication to cause metabolic syndrome (MetS). Our results show significant erosion in the TL of SZ patients under treatment with the atypical antipsychotics clozapine and olanzapine, which cause high-risk for MetS, compared to healthy controls and patients under treatment with medium and low-risk antipsychotics. However, when the analysis was done separately for clozapine and olanzapine, a significant difference remained only for olanzapine. These findings suggest that atypical antipsychotics that cause high-risk for MetS, particularly olanzapine, may modulate leukocyte TL in SZ patients. Future research is required to elucidate if in fact atypical antipsychotics are involved in TL maintenance in SZ subjects and the mechanism by which this occurs. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Cryopreservation of Human Mucosal Leukocytes.

PubMed

Hughes, Sean M; 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

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. 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. 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.

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.

SPECIES SPECIFICITY OF LEUKOCYTIC PYROGENS

PubMed Central

Bornstein, Donald L.; Woods, James W.

1969-01-01

Polymorphonuclear neutrophilic leukocytes of the dog, cat, and goat release leukocytic pyrogen under the same conditions as the heterophile polymorphonuclear leukocytes of the rabbit. The characteristics of the febrile response to an intravenous injection of homologous leukocytic pyrogen in all four species are very similar: a brisk monophasic fever reaching a peak between 30 and 50 min with smooth defervescence to the baseline by 3 hr. Shivering, which is not obvious in the rabbit, is noted in the dog, cat, and goat during the first 30 min. Quantitative differences in response reveal the cat to be the most sensitive of of these species to homologous leukocytic pyrogen, followed by the rabbit, dog, and goat. The response to heterologous pyrogen is in most cases markedly diminished compared to that after equal doses of homologous protein, suggesting the operation of species specificity, although canine and feline pyrogen behaved very similarly in all tests. Species specificity of leukocytic pyrogen is probably related to amino acid substitutions in different species of a common mammalian protein effector molecule. PMID:5343431

Atherosclerosis and leukocyte-endothelial adhesive interactions are increased following acute myocardial infarction in apolipoprotein E deficient mice.

PubMed

Wright, Andrew P; Öhman, Miina K; Hayasaki, Takanori; Luo, Wei; Russo, Hana M; Guo, Chiao; Eitzman, Daniel T

2010-10-01

To determine the effect of myocardial infarction (MI) on progression of atherosclerosis in apolipoprotein E deficient (ApoE-/-) mice. MI was induced following left anterior descending coronary artery (LAD) ligation in wild-type (WT) (n=9) and ApoE-/- (n=25) mice. Compared to sham-operated animals, MI mice demonstrated increased intravascular leukocyte rolling and firm adhesion by intravital microscopy, reflecting enhanced systemic leukocyte-endothelial interactions. To determine if MI was associated with accelerated atherogenesis, LAD ligation was performed in ApoE-/- mice. Six weeks following surgery, atherosclerosis was quantitated throughout the arterial tree by microdissection and Oil-Red-O staining. There was 1.6-fold greater atherosclerotic burden present in ApoE-/- MI mice compared to sham-operated mice. Acute MI accelerates atherogenesis in mice. These results may be related to the increased risk of recurrent ischemic coronary events following MI in humans. Published by Elsevier Ireland Ltd.

A separate role for ICAM-1 and fluid shear in regulating leukocyte interactions with straight regions of venular wall and venular convergences

PubMed Central

Sumagin, Ronen; Lamkin-Kennard, Kathleen A.; Sarelius, Ingrid H

2011-01-01

Objective Variation in expression of adhesion molecules plays a key role in regulating leukocyte behavior, but the contribution of fluid shear to these interactions cannot be ignored. Here we dissected the effects of each of these factors on leukocyte behavior in different venular regions. Methods Leukocyte behavior was quantified in blood perfused microvascular networks in anesthetized mouse cremaster muscle using intravital confocal microscopy. ICAM-1 expression and fluid shear rate were quantified using ICAM-1 fluorescent labeling, fluorescent particle tracking, and computational fluid dynamics. Results TNFα-induced an increase in ICAM-1 expression, and abolished the differences observed among control venules of different sizes. Consequently, leukocyte adhesion was increased to a similar level across all vessel sizes (5.1±0.46 leukocytes/100μm vs. 2.1±0.47 [control]), but remained significantly higher in venular convergences (7.8±0.4). Leukocyte transmigration occurred primarily in the smallest venules and venular convergences (23.9±5.1 and 31.9±2.7 leukocytes/10,000μm2 tissue, respectively). In venular convergences the two inlet vessels are predicted to create a region of low velocity, increasing leukocyte adhesion probability. Conclusions In straight regions of different sized venules the variability in ICAM-1 expression accounts for the differences in leukocyte behavior; in converging regions, fluid shear potentially has a greater effect on leukocyte-EC interactions. PMID:19468960

Maneuver Algorithm for Bearings-Only Target Tracking with Acceleration and Field of View Constraints

NASA Astrophysics Data System (ADS)

Roh, Heekun; Shim, Sang-Wook; Tahk, Min-Jea

2018-05-01

This paper proposes a maneuver algorithm for the agent performing target tracking with bearing angle information only. The goal of the agent is to estimate the target position and velocity based only on the bearing angle data. The methods of bearings-only target state estimation are outlined. The nature of bearings-only target tracking problem is then addressed. Based on the insight from above-mentioned properties, the maneuver algorithm for the agent is suggested. The proposed algorithm is composed of a nonlinear, hysteresis guidance law and the estimation accuracy assessment criteria based on the theory of Cramer-Rao bound. The proposed guidance law generates lateral acceleration command based on current field of view angle. The accuracy criteria supply the expected estimation variance, which acts as a terminal criterion for the proposed algorithm. The aforementioned algorithm is verified with a two-dimensional simulation.

Beam dynamics analysis of dielectric laser acceleration using a fast 6D tracking scheme

NASA Astrophysics Data System (ADS)

Niedermayer, Uwe; Egenolf, Thilo; Boine-Frankenheim, Oliver

2017-11-01

A six-dimensional symplectic tracking approach exploiting the periodicity properties of dielectric laser acceleration (DLA) gratings is presented. The longitudinal kick is obtained from the spatial Fourier harmonics of the laser field within the structure, and the transverse kicks are obtained using the Panofsky-Wenzel theorem. Additionally to the usual, strictly longitudinally periodic gratings, our approach is also applicable to periodicity chirped (subrelativistic) and tilted (deflection) gratings. In the limit of small kicks and short periods we obtain the 6D Hamiltonian, which allows, for example, to obtain matched beam distributions in DLAs. The scheme is applied to beam and grating parameters similar to recently performed experiments. The paper concludes with an outlook to laser based focusing schemes, which are promising to overcome fundamental interaction length limitations, in order to build an entire microchip-sized laser driven accelerator.

Graphs and Tracks Revisited

NASA Astrophysics Data System (ADS)

Christian, Wolfgang; Belloni, Mario

2013-04-01

We have recently developed a Graphs and Tracks model based on an earlier program by David Trowbridge, as shown in Fig. 1. Our model can show position, velocity, acceleration, and energy graphs and can be used for motion-to-graphs exercises. Users set the heights of the track segments, and the model displays the motion of the ball on the track together with position, velocity, and acceleration graphs. This ready-to-run model is available in the ComPADRE OSP Collection at www.compadre.org/osp/items/detail.cfm?ID=12023.

Tracking neutrophil intraluminal crawling, transendothelial migration and chemotaxis in tissue by intravital video microscopy.

PubMed

Xu, Najia; Lei, Xi; Liu, Lixin

2011-09-24

The recruitment of circulating leukocytes from blood stream to the inflamed tissue is a crucial and complex process of inflammation(1,2). In the postcapillary venules of inflamed tissue, leukocytes initially tether and roll on the luminal surface of venular wall. Rolling leukocytes arrest on endothelium and undergo firm adhesion in response to chemokine or other chemoattractants on the venular surface. Many adherent leukocytes relocate from the initial site of adhesion to the junctional extravasation site in endothelium, a process termed intraluminal crawling(3). Following crawling, leukocytes move across endothelium (transmigration) and migrate in extravascular tissue toward the source of chemoattractant (chemotaxis)(4). Intravital microscopy is a powerful tool for visualizing leukocyte-endothelial cell interactions in vivo and revealing cellular and molecular mechanisms of leukocyte recruitment(2,5). In this report, we provide a comprehensive description of using brightfield intravital microscopy to visualize and determine the detailed processes of neutrophil recruitment in mouse cremaster muscle in response to the gradient of a neutrophil chemoattractant. To induce neutrophil recruitment, a small piece of agarose gel (~1-mm(3) size) containing neutrophil chemoattractant MIP-2 (CXCL2, a CXC chemokine) or WKYMVm (Trp-Lys-Tyr-Val-D-Met, a synthetic analog of bacterial peptide) is placed on the muscle tissue adjacent to the observed postcapillary venule. With time-lapsed video photography and computer software ImageJ, neutrophil intraluminal crawling on endothelium, neutrophil transendothelial migration and the migration and chemotaxis in tissue are visualized and tracked. This protocol allows reliable and quantitative analysis of many neutrophil recruitment parameters such as intraluminal crawling velocity, transmigration time, detachment time, migration velocity, chemotaxis velocity and chemotaxis index in tissue. We demonstrate that using this protocol, these

21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 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 (granular...

21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 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 (granular...

21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 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 (granular...

In vitro agglutinin production by earthworm leukocytes.

PubMed

Stein, E A; Cooper, E L

1988-01-01

Leukocytes of the earthworm, Lumbricus terrestris, secrete agglutinins in vitro, as shown by measuring agglutinin titers of the culture medium and by observing secretory rosette formation by leukocytes with erythrocytes. Leukocytes form the highest percentages of secretory rosettes with rabbit erythrocytes (RBC) and with other RBC species in the order: rat, guinea pig, mouse, calf, sheep, horse, goat. Leukocytes displayed allotypic specificity by forming rosettes selectively with erythrocytes from different individual rabbits. Eight sugars inhibited rosette formation, along with the polysaccharide mannan and the glycoproteins thyroglobulin and bovine submaxillary mucin. Cyclohexamide did not affect rosette formation, suggesting that agglutinins may be preformed and stored in leukocytes prior to secretion. Leukocytes also formed E-type rosettes with erythrocytes, but apparently utilized different receptors from those of secretory rosettes since they were not inhibited by the same sugars.

Association between leukocyte telomere length and serum carotenoid in US adults.

PubMed

Min, Kyoung-Bok; Min, Jin-Young

2017-04-01

Telomere length is a biomarker for aging. It is known that oxidative stress can accelerate telomere shortening, whereas antioxidants can delay their shortening. Carotenoids as antioxidants are favorably associated with health- and aging-related diseases caused by oxidative stress, but their association with telomere length is less certain. We investigated the association between blood carotenoid levels and leukocyte telomere length in a representative sample of US adults. We analyzed 3660 participants aged 20 years and older in the 1999-2002 National Health and Nutrition Examination Survey. The levels of carotenoids-alpha-carotene, beta-carotene (trans + cis), beta-cryptoxanthin, combined lutein/zeaxanthin, and trans-lycopene-were measured using high-performance liquid chromatography. The leukocyte telomere length (T/S ratio) was assayed using the quantitative polymerase chain reaction method. A doubling of blood alpha-carotene, beta-carotene (trans + cis), and beta-cryptoxanthin was associated with approximately 2 % longer telomeres. Compared with the lowest carotenoid quartile of alpha-carotene, beta-carotene (trans + cis), and beta-cryptoxanthin, telomere length for adults with the highest quartiles was significantly increased by 5-8 %. We found that increasing levels of blood carotenoid were significantly associated with longer leukocyte telomeres in US adults. High intake of carotenoid-rich food may play a role in protecting telomeres and regulating telomere length.

Computerized detection of leukocytes in microscopic leukorrhea images.

PubMed

Zhang, Jing; Zhong, Ya; Wang, Xiangzhou; Ni, Guangming; Du, Xiaohui; Liu, Juanxiu; Liu, Lin; Liu, Yong

2017-09-01

Detection of leukocytes is critical for the routine leukorrhea exam, which is widely used in gynecological examinations. An elevated vaginal leukocyte count in women with bacterial vaginosis is a strong predictor of vaginal or cervical infections. In the routine leukorrhea exam, the counting of leukocytes is primarily performed by manual techniques. However, the viewing and counting of leukocytes from multiple high-power viewing fields on a glass slide under a microscope leads to subjectivity, low efficiency, and low accuracy. To date, many biological cells in stool, blood, and breast cancer have been studied to realize computerized detection; however, the detection of leukocytes in microscopic leukorrhea images has not been studied. Thus, there is an increasing need for computerized detection of leukocytes. There are two key processes in the computerized detection of leukocytes in digital image processing. One is segmentation; the other is intelligent classification. In this paper, we propose a combined ensemble to detect leukocytes in the microscopic leukorrhea image. After image segmentation and selecting likely leukocyte subimages, we obtain the leukocyte candidates. Then, for intelligent classification, we adopt two methods: feature extraction and classification by a support vector machine (SVM); applying a modified convolutional neural network (CNN) to the larger subimages. If different methods classify a candidate in the same category, the process is finished. If not, the outputs of the methods are provided to a classifier to further classify the candidate. After acquiring leukocyte candidates, we attempted three methods to perform classification. The first approach using features and SVM achieved 88% sensitivity, 97% specificity, and 92.5% accuracy. The second method using CNN achieved 95% sensitivity, 84% specificity, and 89.5% accuracy. Then, in the combination approach, we achieved 92% sensitivity, 95% specificity, and 93.5% accuracy. Finally, the images

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

Synthesis of an optoelectronic system for tracking (OEST) the information track of the optical record carrier based on the acceleration control principle

NASA Astrophysics Data System (ADS)

Zalogin, Stanislav M.; Zalogin, M. S.

1997-02-01

The problem for construction of control algorithm in OEST the information track of the optical record carrier the realization of which is based on the use of accelerations is considered. Such control algorithms render the designed system the properties of adaptability, feeble sensitivity to the system parameter change and the action of disturbing forces what gives known advantages to information carriers with such system under operation in hard climate conditions as well as at maladjustment, workpieces wear and change of friction in the system. In the paper are investigated dynamic characteristics of a closed OEST, it is shown, that the designed stable system with given quality indices is a high-precision one. The validated recommendations as to design of control algorithms parameters are confirmed by results of mathematical simulation of controlled processes. The proposed methods for OEST synthesis on the basis of the control acceleration principle can be recommended for the use at industrial production of optical information record carriers.

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

[Mechanisms of leukocyte formation of endogenous pyrogen].

PubMed

Rybakina, E G; Sorokin, A V

1982-06-01

A study was made of the kinetics of endogenous pyrogen production by rabbit blood and exudate leukocytes and possible role played by the products of activated leukocytes in autoregulation of the process. It was established that accumulation of endogenous pyrogen in the cell precedes its release by stimulated cells. Then the processes of active pyrogen formation and release gel interdependent: pyrogen formed releases from the cell; the lowering of pyrogen concentration in the cell is accompanied by the decrease of its content in the medium. No stimulating effect of the products activated during leukocyte inflammation on pyrogen formation by blood leukocytes was discovered.

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.

CD44 mediated hyaluronan adhesion of Toxoplasma gondii-infected leukocytes.

PubMed

Hayashi, Takeshi; Unno, Akihiro; Baba, Minami; Ohno, Tamio; Kitoh, Katsuya; Takashima, Yasuhiro

2014-04-01

Toxoplasma gondii is an obligate intracellular apicomplexan parasite that infects humans and animals. Ingested parasites cross the intestinal epithelium, invade leukocytes and are then disseminated to peripheral organs. However, the mechanism of extravasation of the infected leukocytes remains poorly understood. In this study, we demonstrate that T. gondii-invaded human and mouse leukocytes express higher level of CD44, a ligand of hyaluronan (HA), and its expression on myeloid and non-myeloid leukocytes causes T. gondii-invaded human and mouse leukocyte to adhere to HA more effectively than non-invaded leukocytes. The specific adherence of parasite-invaded leukocytes was inhibited by anti CD44 antibody. Leukocytes of CD44 knockout mice did not show parasite-invaded leukocyte specific adhesion. Our results indicate that parasite-invaded leukocytes, regardless of whether myeloid or not, gain higher ability to adhere to HA than non-invaded leukocytes, via upregulation of CD44 expression and/or selective invasion to CD44 highly expressing cells. The difference in ability to adhere to HA between parasite-invaded cells and non-invaded neighboring cells might facilitate effective delivery of parasite-invaded leukocytes to the HA-producing endothelial cell surface and/or HA-rich extra cellular matrix. © 2013.

TrackPlot Enhancements: Support for Multiple Animal Tracks and Gyros

DTIC Science & Technology

2015-09-30

visualization and kinematic analysis of marine animal movements derived from archival tag data. Tags are supported that have sensors for pressure, acceleration...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. TrackPlot Enhancements: Support for Multiple Animal ...in combination with accelerometer and magnetometer data. 2) the extraction and frequency analysis of accelerations and rotation in animal

Biomechanics of leukocyte rolling

PubMed Central

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

Angiotensin II–accelerated atherosclerosis and aneurysm formation is attenuated in osteopontin-deficient mice

PubMed Central

Bruemmer, Dennis; Collins, Alan R.; Noh, Grace; Wang, Wei; Territo, Mary; Arias-Magallona, Sarah; Fishbein, Michael C.; Blaschke, Florian; Kintscher, Ulrich; Graf, Kristof; Law, Ronald E.; Hsueh, Willa A.

2003-01-01

Osteopontin (OPN) is expressed in atherosclerotic lesions, particularly in diabetic patients. To determine the role of OPN in atherogenesis, ApoE–/–OPN+/+, ApoE–/–OPN+/–, and ApoE–/–OPN–/– mice were infused with Ang II, inducing vascular OPN expression and accelerating atherosclerosis. Compared with ApoE–/–OPN+/+ mice, ApoE–/–OPN+/– and ApoE–/–OPN–/– mice developed less Ang II–accelerated atherosclerosis. ApoE–/– mice transplanted with bone marrow derived from ApoE–/–OPN–/– mice had less Ang II–induced atherosclerosis compared with animals receiving ApoE–/–OPN+/+ cells. Aortae from Ang II–infused ApoE–/–OPN–/– mice expressed less CD68, C-C-chemokine receptor 2, and VCAM-1. In response to intraperitoneal thioglycollate, recruitment of leukocytes in OPN–/– mice was impaired, and OPN–/– leukocytes exhibited decreased basal and MCP-1–directed migration. Furthermore, macrophage viability in atherosclerotic lesions from Ang II–infused ApoE–/–OPN–/– mice was decreased. Finally, Ang II–induced abdominal aortic aneurysm formation in ApoE–/–OPN–/– mice was reduced and associated with decreased MMP-2 and MMP-9 activity. These data suggest an important role for leukocyte-derived OPN in mediating Ang II–accelerated atherosclerosis and aneurysm formation. PMID:14597759

Endothelial cell regulation of leukocyte infiltration in inflammatory tissues

PubMed Central

Mantovani, A.; Introna, M.; Dejana, E.

1995-01-01

Endothelial cells play an important, active role in the onset and regulation of inflammatory and immune reactions. Through the production of chemokines they attract leukocytes and activate their adhesive receptors. This leads to the anchorage of leukocytes to the adhesive molecules expressed on the endothelial surface. Leukocyte adhesion to endothelial cells is frequently followed by their extravasation. The mechanisms which regulate the passage of leukocytes through endothelial clefts remain to be clarified. Many indirect data suggest that leukocytes might transfer signals to endothelial cells both through the release of active agents and adhesion to the endothelial cell surface. Adhesive molecules (such as PECAM) on the endothelial cell surface might also ‘direct’ leukocytes through the intercellular junction by haptotaxis. The information available on the molecular structure and functional properties of endothelial chemokines, adhesive molecules or junction organization is still fragmentary. Further work is needed to clarify how they interplay in regulating leukocyte infiltration into tissues. PMID:18475659

Genomic signatures characterize leukocyte infiltration in myositis muscles

PubMed Central

2012-01-01

Background Leukocyte infiltration plays an important role in the pathogenesis and progression of myositis, and is highly associated with disease severity. Currently, there is a lack of: efficacious therapies for myositis; understanding of the molecular features important for disease pathogenesis; and potential molecular biomarkers for characterizing inflammatory myopathies to aid in clinical development. Methods In this study, we developed a simple model and predicted that 1) leukocyte-specific transcripts (including both protein-coding transcripts and microRNAs) should be coherently overexpressed in myositis muscle and 2) the level of over-expression of these transcripts should be correlated with leukocyte infiltration. We applied this model to assess immune cell infiltration in myositis by examining mRNA and microRNA (miRNA) expression profiles in muscle biopsies from 31 myositis patients and 5 normal controls. Results Several gene signatures, including a leukocyte index, type 1 interferon (IFN), MHC class I, and immunoglobulin signature, were developed to characterize myositis patients at the molecular level. The leukocyte index, consisting of genes predominantly associated with immune function, displayed strong concordance with pathological assessment of immune cell infiltration. This leukocyte index was subsequently utilized to differentiate transcriptional changes due to leukocyte infiltration from other alterations in myositis muscle. Results from this differentiation revealed biologically relevant differences in the relationship between the type 1 IFN pathway, miR-146a, and leukocyte infiltration within various myositis subtypes. Conclusions Results indicate that a likely interaction between miR-146a expression and the type 1 IFN pathway is confounded by the level of leukocyte infiltration into muscle tissue. Although the role of miR-146a in myositis remains uncertain, our results highlight the potential benefit of deconvoluting the source of

Genomic signatures characterize leukocyte infiltration in myositis muscles.

PubMed

Zhu, Wei; Streicher, Katie; Shen, Nan; Higgs, Brandon W; Morehouse, Chris; Greenlees, Lydia; Amato, Anthony A; Ranade, Koustubh; Richman, Laura; Fiorentino, David; Jallal, Bahija; Greenberg, Steven A; Yao, Yihong

2012-11-21

Leukocyte infiltration plays an important role in the pathogenesis and progression of myositis, and is highly associated with disease severity. Currently, there is a lack of: efficacious therapies for myositis; understanding of the molecular features important for disease pathogenesis; and potential molecular biomarkers for characterizing inflammatory myopathies to aid in clinical development. In this study, we developed a simple model and predicted that 1) leukocyte-specific transcripts (including both protein-coding transcripts and microRNAs) should be coherently overexpressed in myositis muscle and 2) the level of over-expression of these transcripts should be correlated with leukocyte infiltration. We applied this model to assess immune cell infiltration in myositis by examining mRNA and microRNA (miRNA) expression profiles in muscle biopsies from 31 myositis patients and 5 normal controls. Several gene signatures, including a leukocyte index, type 1 interferon (IFN), MHC class I, and immunoglobulin signature, were developed to characterize myositis patients at the molecular level. The leukocyte index, consisting of genes predominantly associated with immune function, displayed strong concordance with pathological assessment of immune cell infiltration. This leukocyte index was subsequently utilized to differentiate transcriptional changes due to leukocyte infiltration from other alterations in myositis muscle. Results from this differentiation revealed biologically relevant differences in the relationship between the type 1 IFN pathway, miR-146a, and leukocyte infiltration within various myositis subtypes. Results indicate that a likely interaction between miR-146a expression and the type 1 IFN pathway is confounded by the level of leukocyte infiltration into muscle tissue. Although the role of miR-146a in myositis remains uncertain, our results highlight the potential benefit of deconvoluting the source of transcriptional changes in myositis muscle or other

Accelerated event-by-event Monte Carlo microdosimetric calculations of electrons and protons tracks on a multi-core CPU and a CUDA-enabled GPU.

PubMed

Kalantzis, Georgios; Tachibana, Hidenobu

2014-01-01

For microdosimetric calculations event-by-event Monte Carlo (MC) methods are considered the most accurate. The main shortcoming of those methods is the extensive requirement for computational time. In this work we present an event-by-event MC code of low projectile energy electron and proton tracks for accelerated microdosimetric MC simulations on a graphic processing unit (GPU). Additionally, a hybrid implementation scheme was realized by employing OpenMP and CUDA in such a way that both GPU and multi-core CPU were utilized simultaneously. The two implementation schemes have been tested and compared with the sequential single threaded MC code on the CPU. Performance comparison was established on the speed-up for a set of benchmarking cases of electron and proton tracks. A maximum speedup of 67.2 was achieved for the GPU-based MC code, while a further improvement of the speedup up to 20% was achieved for the hybrid approach. The results indicate the capability of our CPU-GPU implementation for accelerated MC microdosimetric calculations of both electron and proton tracks without loss of accuracy. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

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.

PBMC telomerase activity, but not leukocyte telomere length, correlates with hippocampal volume in major depression

PubMed Central

Wolkowitz, Owen M.; Mellon, Synthia H.; Lindqvist, Daniel; Epel, Elissa S.; Blackburn, Elizabeth H.; Lin, Jue; Reus, Victor I.; Burke, Heather; Rosser, Rebecca; Mahan, Laura; Mackin, Scott; Yang, Tony; Weiner, Michael; Mueller, Susanne

2015-01-01

Accelerated cell aging, indexed in peripheral leukocytes by telomere length and in peripheral blood mononuclear cells (PBMCs) by telomerase activity, has been reported in several studies of major depressive disorder (MDD). However, the relevance of these peripheral measures for brain indices that are presumably more directly related to MDD pathophysiology is unknown. In this study, we explored the relationship between PBMC telomerase activity and leukocyte telomere length and magnetic resonance imaging-estimated hippocampal volume in un-medicated depressed individuals and healthy controls. We predicted that, to the extent peripheral and central telomerase activity are directly related, PBMC telomerase activity would be positively correlated with hippocampal volume, perhaps due to hippocampal telomerase-associated neurogenesis, neuroprotection or neurotrophic facilitation, and that this effect would be clearer in individuals with increased PBMC telomerase activity, as previously reported in un-medicated MDD. We did not have specific hypotheses regarding the relationship between leukocyte telomere length and hippocampal volume, due to conflicting reports in the published literature. We found, in 25 un-medicated MDD subjects, that PBMC telomerase activity was significantly positively correlated with hippocampal volume; this relationship was not observed in 18 healthy controls. Leukocyte telomere length was not significantly related to hippocampal volume in either group (19 unmedicated MDD subjects and 17 healthy controls). Although the nature of the relationship between peripheral telomerase activity and telomere length and the hippocampus is unclear, these preliminary data are consistent with the possibility that PBMC telomerase activity indexes, and may provide a novel window into, hippocampal neuroprotection and/or neurogenesis in MDD. PMID:25773002

Platelet-rich preparations to improve healing. Part II: platelet activation and enrichment, leukocyte inclusion, and other selection criteria.

PubMed

Davis, Vicki L; Abukabda, Alaeddin B; Radio, Nicholas M; Witt-Enderby, Paula A; Clafshenkel, William P; Cairone, J Vito; Rutkowski, James L

2014-08-01

Multiple platelet-rich preparations have been reported to improve wound and bone healing, such as platelet-rich plasma (PRP) and platelet rich fibrin (PRF). The different methods employed during their preparation are important, as they influence the quality of the product applied to a wound or surgical site. Besides the general protocol for preparing the platelet-rich product (discussed in Part 1 of this review), multiple choices need to be considered during its preparation. For example, activation of the platelets is required for the release and enmeshment of growth factors, but the method of activation may influence the resulting matrix, growth factor availability, and healing. Additionally, some methods enrich leukocytes as well as platelets, but others are designed to be leukocyte-poor. Leukocytes have many important roles in healing and their inclusion in PRP results in increased platelet concentrations. Platelet and growth factor enrichment reported for the different types of platelet-rich preparations are also compared. Generally, TGF-β1 and PDGF levels were higher in preparations that contain leukocytes compared to leukocyte-poor PRP. However, platelet concentration may be the most reliable criterion for comparing different preparations. These and other criteria are described to help guide dental and medical professionals, in large and small practices, in selecting the best procedures for their patients. The healing benefits of platelet-rich preparations along with the low risk and availability of simple preparation procedures should encourage more clinicians to incorporate platelet-rich products in their practice to accelerate healing, reduce adverse events, and improve patient outcomes.

Accurate and efficient spin integration for particle accelerators

DOE PAGES

Abell, Dan T.; Meiser, Dominic; Ranjbar, Vahid H.; ...

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 formore » the entire RHIC lattice. We exploit the inherently data-parallel nature of spin tracking to accelerate our algorithms on graphics processing units.« less

Increased circulating leukocyte-derived microparticles in ischemic cerebrovascular disease.

PubMed

He, Zhangping; Tang, Yanyan; Qin, Chao

2017-06-01

Circulating leukocyte-derived microparticles act as proinflammatory mediators that reflect vascular inflammation. In this study, we examined the hypothesis that the quantity of leukocyte-derived microparticles is increased in patients with ischemic cerebrovascular diseases, and investigated utility of various phenotypes of leukocyte-derived microparticles as specific biomarkers of vascular inflammation injury. Additionally we focused on identifying leukocyte-derived microparticles that may be correlated with stroke severity in acute ischemic stroke patients. The plasma concentration of leukocyte-derived microparticles obtained by a series of centrifugations of 76 consecutive patients with ischemic cerebrovascular diseases and 70 age-, sex-, and race-matched healthy controls were determined by flow cytometry. Significantly elevated numbers of leukocyte (CD45+), monocyte (CD14+), lymphocyte (CD4+), granulocyte (CD15+) derived microparticles were found in the plasma samples of patients ischemic cerebrovascular diseases, compared to healthy controls (p<0.05). Furthermore, the plasma levels of CD14+ microparticles were significantly correlated with stroke severity (r=0.355, p=0.019), cerebral vascular stenosis severity (r=0.255, p=0.025) and stroke subtype (r=0.242, p=0.036). No association with stroke was observed for other leukocyte-derived phenotypes. These results demonstrate that circulating leukocyte-derived microparticles amounts are increased in patients with ischemic cerebrovascular diseases, compared with healthy controls. As proinflammatory mediators, leukocyte-derived microparticles may contribute to vascular inflammatory and the inflammatory process in acute ischemic stroke. Levels of CD14+ microparticles may be a promising biomarker of ischemic severity and outcome of stroke in the clinic. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthesis of endogenous pyrogen by rabbit leukocytes.

PubMed

Moore, D M; Murphy, P A; Chesney, P J; Wood, W B

1973-05-01

Rabbit ieukocytes from peritoneal exudates and from blood were stimulated to form leukocyte pyrogen in the presence of radiolabeled amino acids. The stimuli used were endotoxin, phagocytosis, and tuberculin. The crude leukocyte pyrogen samples were purified; pyrogen from exudate cells was rendered homogeneous; pyrogen from blood cells was still contaminated with other proteins. All the purified pyrogens were radioactive; and for all it was shown that radioactivity and pyrogenic activity coincided on electrophoresis at pH 3.5 and pH 9 in acrylamide and on isoelectric focusing in acrylamide. Furthermore, pyrogens obtained from exudate cells stimulated in different ways, or from blood cells and exudate cells stimulated with endotoxin, appeared to be identical. These results suggest that leukocyte pyrogen was synthesized de novo from amino acid precursors and that leukocytes made the same pyrogen whatever the stimulus used to activate them.

The effect of massage on acceleration and sprint performance in track & field athletes.

PubMed

Moran, Ryan N; Hauth, John M; Rabena, Robert

2018-02-01

To examine the acute effects of pre-competition massage on acceleration and sprint performance in collegiate track and field athletes. Seventeen collegiate male (n = 9) and female (N = 8) track and field athletes participated in the study. Athletes were assigned to a counterbalanced, repeated measures designed experiment testing four treatment conditions of a pre-competition massage, dynamic warm-up, combination of a massage and warm-up, and a placebo ultrasound. The reliability between treatments was very high (ICC range: 0.94-0.98) and displayed a high internal consistency (Cronbach α = 0.96). Inter-item correlations for treatments were strong at all time intervals (20-m r = 0.74-0.90; 30-m r = 0.87-0.95; 60-m r = 0.88-0.95). There were no significant differences between the four treatments and performance (p = 0.70). Massage decreased 60-meter sprint performance in comparison to the traditional warm-up, although the combination of the massage and warm-up appeared to have no greater difference than the warm-up alone. Massage prior to competition remains questionable due to a lack of effectiveness in improving sprint performance. Further, pre-competition massage may not be more effective as a pre-event modality, over a traditional warm-up. Copyright © 2017 Elsevier Ltd. All rights reserved.

Indium-111 leukocyte imaging in patients with rheumatoid arthritis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uno, K.; Matsui, N.; Nohira, K.

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 determinedmore » 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.« less

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.

Track profile approximation using railcar body acceleration data.

DOT National Transportation Integrated Search

2014-12-01

Accelerations are frequently measured from the car body of a rail vehicle, which is mounted above one or more suspension : systems. Measuring accelerations in the car body is largely done for convenience, as mounting an accelerometer to a truck or ax...

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

SYNTHESIS OF ENDOGENOUS PYROGEN BY RABBIT LEUKOCYTES

PubMed Central

Moore, Douglas M.; Murphy, Patrick A.; Chesney, P. Joan; Wood, W. B.

1973-01-01

Rabbit ieukocytes from peritoneal exudates and from blood were stimulated to form leukocyte pyrogen in the presence of radiolabeled amino acids. The stimuli used were endotoxin, phagocytosis, and tuberculin. The crude leukocyte pyrogen samples were purified; pyrogen from exudate cells was rendered homogeneous; pyrogen from blood cells was still contaminated with other proteins. All the purified pyrogens were radioactive; and for all it was shown that radioactivity and pyrogenic activity coincided on electrophoresis at pH 3.5 and pH 9 in acrylamide and on isoelectric focusing in acrylamide. Furthermore, pyrogens obtained from exudate cells stimulated in different ways, or from blood cells and exudate cells stimulated with endotoxin, appeared to be identical. These results suggest that leukocyte pyrogen was synthesized de novo from amino acid precursors and that leukocytes made the same pyrogen whatever the stimulus used to activate them. PMID:4573840

Advances in RNAi therapeutic delivery to leukocytes using lipid nanoparticles.

PubMed

Ramishetti, Srinivas; Landesman-Milo, Dalit; Peer, Dan

2016-11-01

Small interfering RNAs (siRNAs) therapeutics has advanced into clinical trials for liver diseases and solid tumors, but remain a challenge for manipulating leukocytes fate due to lack of specificity and safety issues. Leukocytes ingest pathogens and defend the body through a complex network. They are also involved in the pathogeneses of inflammation, viral infection, autoimmunity and cancers. Modulating gene expression in leukocytes using siRNAs holds great promise to treat leukocyte-mediated diseases. Leukocytes are notoriously hard to transduce with siRNAs and are spread throughout the body often located deep in tissues, therefore developing an efficient systemic delivery strategy is still a challenge. Here, we discuss recent advances in siRNA delivery to leukocyte subsets such as macrophages, monocytes, dendritic cells and lymphocytes. We focus mainly on lipid-based nanoparticles (LNPs) comprised of new generation of ionizable lipids and their ability to deliver siRNA to primary or malignant leukocytes in a targeted manner. Special emphasis is made on LNPs targeted to subsets of leukocytes and we detail a novel microfluidic mixing technology that could aid in changing the landscape of process development of LNPs from a lab tool to a potential novel therapeutic modality.

Leukocyte adhesion: High-speed cells with ABS.

PubMed

van der Merwe, P A

1999-06-03

In order to decide where to exit blood vessels and enter tissues, leukocytes roll along endothelial surfaces. Recent studies suggest that an 'automatic braking system' (ABS), involving selectin cell-adhesion molecules, enables leukocytes to roll at a fairly constant velocity despite large variations in blood flow rate.

Genetics Home Reference: leukocyte adhesion deficiency type 1

MedlinePlus

... adhesion deficiency type 1 Leukocyte adhesion deficiency type 1 Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Leukocyte adhesion deficiency type 1 is a ...

Arithmetic of five-part of leukocytes based on image process

NASA Astrophysics Data System (ADS)

Li, Yian; Wang, Guoyou; Liu, Jianguo

2007-12-01

This paper apply computer image processing and pattern recognizition methods to solve the problem of auto classification and counting of leukocytes (white blood cell) in peripheral blood. In this paper a new leukocyte arithmetic of five-part based on image process and pattern recognizition is presented, which relized auto classify of leukocyte. The first aim is detect the leukocytes . A major requirement of the whole system is to classify these leukocytes to 5 classes. This arithmetic bases on notability mechanism of eyes, process image by sequence, divides up leukocytes and pick up characters. Using the prior kwonledge of cells and image shape information, this arithmetic divides up the probable shape of Leukocyte first by a new method based on Chamfer and then gets the detail characters. It can reduce the mistake judge rate and the calculation greatly. It also has the learning fuction. This paper also presented a new measurement of karyon's shape which can provide more accurate information. This algorithm has great application value in clinical blood test .

Simultaneous Multislice Echo Planar Imaging With Blipped Controlled Aliasing in Parallel Imaging Results in Higher Acceleration: A Promising Technique for Accelerated Diffusion Tensor Imaging of Skeletal Muscle.

PubMed

Filli, Lukas; Piccirelli, Marco; Kenkel, David; Guggenberger, Roman; Andreisek, Gustav; Beck, Thomas; Runge, Val M; Boss, Andreas

2015-07-01

The aim of this study was to investigate the feasibility of accelerated diffusion tensor imaging (DTI) of skeletal muscle using echo planar imaging (EPI) applying simultaneous multislice excitation with a blipped controlled aliasing in parallel imaging results in higher acceleration unaliasing technique. After federal ethics board approval, the lower leg muscles of 8 healthy volunteers (mean [SD] age, 29.4 [2.9] years) were examined in a clinical 3-T magnetic resonance scanner using a 15-channel knee coil. The EPI was performed at a b value of 500 s/mm2 without slice acceleration (conventional DTI) as well as with 2-fold and 3-fold acceleration. Fractional anisotropy (FA) and mean diffusivity (MD) were measured in all 3 acquisitions. Fiber tracking performance was compared between the acquisitions regarding the number of tracks, average track length, and anatomical precision using multivariate analysis of variance and Mann-Whitney U tests. Acquisition time was 7:24 minutes for conventional DTI, 3:53 minutes for 2-fold acceleration, and 2:38 minutes for 3-fold acceleration. Overall FA and MD values ranged from 0.220 to 0.378 and 1.595 to 1.829 mm2/s, respectively. Two-fold acceleration yielded similar FA and MD values (P ≥ 0.901) and similar fiber tracking performance compared with conventional DTI. Three-fold acceleration resulted in comparable MD (P = 0.199) but higher FA values (P = 0.006) and significantly impaired fiber tracking in the soleus and tibialis anterior muscles (number of tracks, P < 0.001; anatomical precision, P ≤ 0.005). Simultaneous multislice EPI with blipped controlled aliasing in parallel imaging results in higher acceleration can remarkably reduce acquisition time in DTI of skeletal muscle with similar image quality and quantification accuracy of diffusion parameters. This may increase the clinical applicability of muscle anisotropy measurements.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hangen, D.H.; Segall, G.M.; Harney, E.W.

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 fallmore » 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.« less

Gene expression profile of human Down syndrome leukocytes.

PubMed

Malagó, Wilson; Sommer, César A; Del Cistia Andrade, Camillo; Soares-Costa, Andrea; Abrao Possik, Patricia; Cassago, Alexandre; Santejo Silveira, Henrique C; Henrique-Silva, Flavio

2005-08-01

Identification of differences in the gene expression patterns of Down syndrome and normal leukocytes. We constructed the first Down syndrome leukocyte serial analysis of gene expression (SAGE) library from a 28 year-old patient. This library was analyzed and compared with a normal leukocyte SAGE library using the eSAGE software. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to validate the results. We found that a large number of unidentified transcripts were overexpressed in Down syndrome leukocytes and some transcripts coding for growth factors (e.g. interleukin 8, IL-8), ribosomaproteins (e.g. L13a, L29, and L37), and transcription factors (e.g., Jun B, Jun D, and C/EBP beta) were underexpressed. The SAGE data were successfully validated for the genes IL-8, CXCR4, BCL2A1, L13a, L29, L37, and GTF3A using RT-PCR. Our analysis identified significant changes in the expression pattern of Down syndrome leukocytes compared with normal ones, including key regulators of growth and proliferation, ribosomal proteins, and a large number of overexpressed transcripts that were not matched in UniGene clusters and that may represent novel genes related to Down syndrome. This study offers a new insight into transcriptional changes in Down syndrome leukocytes and indicates candidate genes for further investigations into the molecular mechanism of Down syndrome pathology.

Leukocyte diversity in resolving and nonresolving mechanisms of cardiac remodeling.

PubMed

Tourki, Bochra; Halade, Ganesh

2017-10-01

In response to myocardial infarction (MI), time-dependent leukocyte infiltration is critical to program the acute inflammatory response. Post-MI leukocyte density, residence time in the infarcted area, and exit from the infarcted injury predict resolving or nonresolving inflammation. Overactive or unresolved inflammation is the primary determinant in heart failure pathology post-MI. Here, our review describes supporting evidence that the acute inflammatory response also guides the generation of healing and regenerative mediators after cardiac damage. Time-dependent leukocyte density and diversity and the magnitude of myocardial injury is responsible for the resolving and nonresolving pathway in myocardial healing. Post MI, the diversity of leukocytes, such as neutrophils, macrophages, and lymphocytes, has been explored that regulate the clearance of deceased cardiomyocytes by using the classic and reparative pathways. Among the innovative factors and intermediates that have been recognized as essential in acute the self-healing and clearance mechanism, we highlight specialized proresolving mediators as the emerging factor for post-MI reparative mechanisms-translational leukocyte modifiers, such as aging, the source of leukocytes, and the milieu around the leukocytes. In the clinical setting, it is possible that leukocyte diversity is more prominent as a result of risk factors, such as obesity, diabetes, and hypertension. Pharmacologic agents are critical modifiers of leukocyte diversity in healing mechanisms that may impair or stimulate the clearance mechanism. Future research is needed, with a focused approach to understand the molecular targets, cellular effectors, and receptors. A clear understanding of resolving and nonresolving inflammation in myocardial healing will help to develop novel targets with major emphasis on the resolution of inflammation in heart failure pathology.-Tourki, B., Halade, G. Leukocyte diversity in resolving and nonresolving mechanisms

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.

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.

A practical approach to tramway track condition monitoring: vertical track defects detection and identification using time-frequency processing technique

NASA Astrophysics Data System (ADS)

Bocz, Péter; Vinkó, Ákos; Posgay, Zoltán

2018-03-01

This paper presents an automatic method for detecting vertical track irregularities on tramway operation using acceleration measurements on trams. For monitoring of tramway tracks, an unconventional measurement setup is developed, which records the data of 3-axes wireless accelerometers mounted on wheel discs. Accelerations are processed to obtain the vertical track irregularities to determine whether the track needs to be repaired. The automatic detection algorithm is based on time-frequency distribution analysis and determines the defect locations. Admissible limits (thresholds) are given for detecting moderate and severe defects using statistical analysis. The method was validated on frequented tram lines in Budapest and accurately detected severe defects with a hit rate of 100%, with no false alarms. The methodology is also sensitive to moderate and small rail surface defects at the low operational speed.

Sex differences in leukocyte invasion in injured murine skeletal muscle.

PubMed

St Pierre Schneider, B; Correia, L A; Cannon, J G

1999-06-01

The three aims of this study were to describe the time course of leukocyte invasion in injured soleus muscles of male and female mice, to determine if differential subsets of leukocytes accumulate in intramyofiber and interstitial sites, and to determine if significant sex differences exist in invading leukocyte concentrations. Fifty sexually mature C57BL/6J mice (aged 11-12 weeks) underwent unilateral hindlimb muscle injury induced by lengthening contractions. This procedure models the muscle injury that can occur through strenuous exercise or overuse in humans. After 1, 3, 5, or 7 days of recovery, the injured and contralateral, uninjured solei were dissected and prepared for morphologic analysis. We found that leukocytes had invaded injured myofibers at 1-day postinjury for both sexes. Different subsets of leukocytes accumulated within damaged myofibers and the interstitium. Significantly fewer myofibers were invaded by acid phosphatase-positive leukocytes in females. Interstitial ER-BMDM1 leukocyte concentrations peaked in females at 7 days postinjury in comparison to 5 days postinjury in males. These findings expand nursing's knowledge base regarding the potential effect of gender on recovery from acute muscle injury.

Long-Term Leukocyte Filtration Should Be Avoided during Extracorporeal Circulation

PubMed Central

Tang, Jiali; Tao, Kaiyu; Zhou, Jing; Zhang, Chongwei; Gong, Lina; Luo, Nanfu

2013-01-01

Filtration during extracorporeal circulation (ECC) not only removes but also activates leukocytes; therefore, long-term leukocyte filtration may cause adverse effects. In the present study, we tested this hypothesis by priming ECC with 300 mL of canine blood and examining filtration effects in 3 groups (n = 6 each) during 60 min ECC. In the control group (Group C) blood was filtrated with an arterial filter for 60 min; in long-term (Group L) and short-term (Group S) groups, blood was filtrated with a leukocyte filter for 60 and 5 min. We found that about 90% of leukocytes were removed after 5 min of filtration in both Groups L and S. Although leukocyte count continued to reduce, mean fluorescent intensities of CD11/CD18, free hemoglobin, and neutrophil elastase increased in Group L and were higher than those in Groups C and S at 60 min. Leukocyte rupture, cytoplasmic leakage, and circulating naked nuclei were also found in Group L. The data support our hypothesis that long-term filtration can induce inflammation and lead to leukocyte destruction. PMID:24453424

Accelerating CR-39 Track Detector Processing by Utilizing UV

NASA Astrophysics Data System (ADS)

Sparling, Jonathan; Padalino, Stephen; McLean, James; Sangster, Craig; Regan, Sean

2017-10-01

The use of CR-39 plastic as a Solid State Nuclear Track Detector is an effective technique for obtaining data in high energy particle experiments including inertial confinement fusion. To reveal particle tracks after irradiation, CR-39 is chemically etched in NaOH at 80°C, producing micron-scale signal pits at the nuclear track sites. It has been shown that illuminating CR-39 with UV light prior to etching increases bulk and track etch rates, especially when combined with elevated temperature. Spectroscopic analysis for amorphous solids has helped identify which UV wavelengths are most effective at enhancing etch rates. Absorption peaks found in the near infrared range provide for efficient sample heating, and may allow targeting cooperative IR-UV chemistry. Avoiding UV induced noise can be achieved through variations in absorption depths with wavelength. Vacuum drying and water absorption tests allow measurement of the resulting variation of bulk etch rate with depth. Funded in part by the NSF and an Department of Energy Grant through the Lab of Laser Energetics.

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

PubMed Central

Irimia, Daniel; Ellett, Felix

2016-01-01

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

An agent-based model of leukocyte transendothelial migration during atherogenesis.

PubMed

Bhui, Rita; Hayenga, Heather N

2017-05-01

A vast amount of work has been dedicated to the effects of hemodynamics and cytokines on leukocyte adhesion and trans-endothelial migration (TEM) and subsequent accumulation of leukocyte-derived foam cells in the artery wall. However, a comprehensive mechanobiological model to capture these spatiotemporal events and predict the growth and remodeling of an atherosclerotic artery is still lacking. Here, we present a multiscale model of leukocyte TEM and plaque evolution in the left anterior descending (LAD) coronary artery. The approach integrates cellular behaviors via agent-based modeling (ABM) and hemodynamic effects via computational fluid dynamics (CFD). In this computational framework, the ABM implements the diffusion kinetics of key biological proteins, namely Low Density Lipoprotein (LDL), Tissue Necrosis Factor alpha (TNF-α), Interlukin-10 (IL-10) and Interlukin-1 beta (IL-1β), to predict chemotactic driven leukocyte migration into and within the artery wall. The ABM also considers wall shear stress (WSS) dependent leukocyte TEM and compensatory arterial remodeling obeying Glagov's phenomenon. Interestingly, using fully developed steady blood flow does not result in a representative number of leukocyte TEM as compared to pulsatile flow, whereas passing WSS at peak systole of the pulsatile flow waveform does. Moreover, using the model, we have found leukocyte TEM increases monotonically with decreases in luminal volume. At critical plaque shapes the WSS changes rapidly resulting in sudden increases in leukocyte TEM suggesting lumen volumes that will give rise to rapid plaque growth rates if left untreated. Overall this multi-scale and multi-physics approach appropriately captures and integrates the spatiotemporal events occurring at the cellular level in order to predict leukocyte transmigration and plaque evolution.

An agent-based model of leukocyte transendothelial migration during atherogenesis

PubMed Central

Bhui, Rita; Hayenga, Heather N.

2017-01-01

A vast amount of work has been dedicated to the effects of hemodynamics and cytokines on leukocyte adhesion and trans-endothelial migration (TEM) and subsequent accumulation of leukocyte-derived foam cells in the artery wall. However, a comprehensive mechanobiological model to capture these spatiotemporal events and predict the growth and remodeling of an atherosclerotic artery is still lacking. Here, we present a multiscale model of leukocyte TEM and plaque evolution in the left anterior descending (LAD) coronary artery. The approach integrates cellular behaviors via agent-based modeling (ABM) and hemodynamic effects via computational fluid dynamics (CFD). In this computational framework, the ABM implements the diffusion kinetics of key biological proteins, namely Low Density Lipoprotein (LDL), Tissue Necrosis Factor alpha (TNF-α), Interlukin-10 (IL-10) and Interlukin-1 beta (IL-1β), to predict chemotactic driven leukocyte migration into and within the artery wall. The ABM also considers wall shear stress (WSS) dependent leukocyte TEM and compensatory arterial remodeling obeying Glagov’s phenomenon. Interestingly, using fully developed steady blood flow does not result in a representative number of leukocyte TEM as compared to pulsatile flow, whereas passing WSS at peak systole of the pulsatile flow waveform does. Moreover, using the model, we have found leukocyte TEM increases monotonically with decreases in luminal volume. At critical plaque shapes the WSS changes rapidly resulting in sudden increases in leukocyte TEM suggesting lumen volumes that will give rise to rapid plaque growth rates if left untreated. Overall this multi-scale and multi-physics approach appropriately captures and integrates the spatiotemporal events occurring at the cellular level in order to predict leukocyte transmigration and plaque evolution. PMID:28542193

Penetration of equine leukocytes by merozoites of Sarcocystis neurona.

PubMed

Lindsay, David S; Mitchell, Sheila M; Yang, Jibing; Dubey, J P; Gogal, Robert M; Witonsky, Sharon G

2006-06-15

Horses are considered accidental hosts for Sarcocystis neurona and they often develop severe neurological disease when infected with this parasite. Schizont stages develop in the central nervous system (CNS) and cause the neurological lesions associated with equine protozoal myeloencephalitis. The present study was done to examine the ability of S. neurona merozoites to penetrate and develop in equine peripheral blood leukocytes. These infected host cells might serve as a possible transport mechanism into the CNS. S. neurona merozoites penetrated equine leukocytes within 5 min of co-culture. Infected leukocytes were usually monocytes. Infected leukocytes were present up to the final day of examination at 3 days. Up to three merozoites were present in an infected monocyte. No development to schizont stages was observed. All stages observed were in the host cell cytoplasm. We postulate that S. neurona merozoites may cross the blood brain barrier hidden inside leukocytes. Once inside the CNS these merozoites can egress and invade additional cells and cause encephalitis.

Leukocyte-reduced blood components: patient benefits and practical applications.

PubMed

Higgins, V L

1996-05-01

To review the various types of filters used for red blood cell and platelet transfusions and to explain the trend in the use of leukocyte removal filters, practical information about their use, considerations in the selection of a filtration method, and cost-effectiveness issues. Published articles, books, and the author's experience. Leukocyte removal filters are used to reduce complications associated with transfused white blood cells that are contained in units of red blood cells and platelets. These complications include nonhemolytic febrile transfusion reactions (NHFTRs), alloimmunization and refractoriness to platelet transfusion, transfusion-transmitted cytomegalovirus (CMV), and immunomodulation. Leukocyte removal filters may be used at the bedside, in a hospital blood bank, or in a blood collection center. Factors that affect the flow rate of these filters include the variations in the blood component, the equipment used, and filter priming. Studies on the cost-effectiveness of using leukocyte-reduced blood components demonstrate savings based on the reduction of NHFTRs, reduction in the number of blood components used, and the use of filtered blood components as the equivalent of CMV seronegative-screened products. The use of leukocyte-reduced blood components significantly diminishes or prevents many of the adverse transfusion reactions associated with donor white blood cells. Leukocyte removal filters are cost-effective, and filters should be selected based on their ability to consistently achieve low leukocyte residual levels as well as their ease of use. Physicians may order leukocyte-reduced blood components for specific patients, or the components may be used because of an established institutional transfusion policy. Nurses often participate in deciding on a filtration method, primarily based on ease of use. Understanding the considerations in selecting a filtration method will help nurses make appropriate decisions to ensure quality patient care.

Does leukocyte-poor or leukocyte-rich platelet-rich plasma applied with biopolymers have superiority to conventional platelet-rich plasma applications on chondrocyte proliferation?

PubMed

Yaşar Şirin, Duygu; Yılmaz, İbrahim; İsyar, Mehmet; Öznam, Kadir; Mahiroğulları, Mahir

2017-12-01

This study aims to investigate the possible effects of leukocyte concentration in the content of platelet-rich plasma (PRP) and the administration of PRP using a drug delivery system on chondrocyte proliferation in vitro conditions. Blood from nine male patients (mean age 65 years; range 49 to 81 years) with advanced stage osteoarthritis who had not responded to medical or conservative treatments and underwent total knee arthroplasty was used to prepare two formulations: PRP with low concentration leukocytes (2000-4000 leukocytes/µL) was designated as pure PRP (P-PRP), whereas PRP with high concentration leukocytes (9000-11000 leukocytes/µL) as leukocyte-rich PRP (L-PRP). Samples were divided into five groups as control group (group 1), chondrocyte cultures with P-PRP applied directly (group 2), chondrocyte cultures with L-PRP applied directly (group 3), chondrocytes co-cultured with P-PRP applied hydrogel (group 4), and chondrocytes co-cultured with L-PRP applied hydrogel (group 5). In all groups; cell morphology, viability and proliferation were compared with the expression of stage-specific embryonic antigen-1 (SSEA-1), a precondrocyte marker. Maximum cell proliferation and SSEA-1 expression occurred in group 4, with a statistically significant correlation between SSEA-1 expression and cell proliferation. Our study showed the importance of leukocyte concentration of PRP and efficiency of delivery systems such as hydrogel and that L-PRP administered with a delivery system is more efficient than conventional applications of PRP in the treatment of cartilage damage.

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.

Leukocytes as carriers for targeted cancer drug delivery.

PubMed

Mitchell, Michael J; King, Michael R

2015-03-01

Metastasis contributes to over 90% of cancer-related deaths. Numerous nanoparticle platforms have been developed to target and treat cancer, yet efficient delivery of these systems to the appropriate site remains challenging. Leukocytes, which share similarities to tumor cells in terms of their transport and migration through the body, are well suited to serve as carriers of drug delivery systems to target cancer sites. This review focuses on the use and functionalization of leukocytes for therapeutic targeting of metastatic cancer. Tumor cell and leukocyte extravasation, margination in the bloodstream, and migration into soft tissue are discussed, along with the potential to exploit these functional similarities to effectively deliver drugs. Current nanoparticle-based drug formulations for the treatment of cancer are reviewed, along with methods to functionalize delivery vehicles to leukocytes, either on the surface and/or within the cell. Recent progress in this area, both in vitro and in vivo, is also discussed, with a particular emphasis on targeting cancer cells in the bloodstream as a means to interrupt the metastatic process. Leukocytes interact with cancer cells both in the bloodstream and at the site of solid tumors. These interactions can be utilized to effectively deliver drugs to targeted areas, which can reduce both the amount of drug required and various nonspecific cytotoxic effects within the body. If drug delivery vehicle functionalization does not interfere with leukocyte function, this approach may be utilized to neutralize tumor cells in the bloodstream to prevent the formation of new metastases, and also to deliver drugs to metastatic sites within tissues.

Relationships between leukocytes and Hepatozoon spp. In green frogs, Rana clamitans.

PubMed

Shutler, Dave; Smith, Todd G; Robinson, Stephen R

2009-01-01

There are few published data on amphibian leukocyte profiles, and relationships between amphibian leukocytes and parasites are even less well known. Using counts from 35 pairs of blood smears taken 2 days apart, we tested for correlations between leukocyte proportions and infection intensities of Hepatozoon spp. (either Hepatozoon catesbianae or Hepatozoon clamatae) in green frogs (Rana clamitans). On average (SE), we counted 65.4 (1.7) lymphocytes, 14.0 (1.3) neutrophils, 19.3 (1.6) eosinophils, 0.9 (0.1) monocytes, and 0.4 (0.1) basophils per 100 leukocytes. All frogs harbored Hepatozoon spp. (median seven parasites per 100 leukocytes; range 1-250). Significant relationships were not observed between numbers of leukocytes and infection intensities of Hepatozoon spp. Among the possible explanations for these null results are that Hepatozoon spp. is benign, that Hepatozoon spp. is able to evade detection by the immune system, that Hepatozoon spp. is able to manipulate leukocyte investment, or that other unmeasured or undetected parasites were more important in affecting immune response.

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.

Leukocytes as carriers for targeted cancer drug delivery

PubMed Central

Mitchell, Michael J

2017-01-01

Introduction Metastasis contributes to over 90% of cancer-related deaths. Numerous nanoparticle platforms have been developed to target and treat cancer, yet efficient delivery of these systems to the appropriate site remains challenging. Leukocytes, which share similarities to tumor cells in terms of their transport and migration through the body, are well suited to serve as carriers of drug delivery systems to target cancer sites. Areas covered This review focuses on the use and functionalization of leukocytes for therapeutic targeting of metastatic cancer. Tumor cell and leukocyte extravasation, margination in the bloodstream, and migration into soft tissue are discussed, along with the potential to exploit these functional similarities to effectively deliver drugs. Current nanoparticle-based drug formulations for the treatment of cancer are reviewed, along with methods to functionalize delivery vehicles to leukocytes, either on the surface and/or within the cell. Recent progress in this area, both in vitro and in vivo, is also discussed, with a particular emphasis on targeting cancer cells in the bloodstream as a means to interrupt the metastatic process. Expert opinion Leukocytes interact with cancer cells both in the bloodstream and at the site of solid tumors. These interactions can be utilized to effectively deliver drugs to targeted areas, which can reduce both the amount of drug required and various nonspecific cytotoxic effects within the body. If drug delivery vehicle functionalization does not interfere with leukocyte function, this approach may be utilized to neutralize tumor cells in the bloodstream to prevent the formation of new metastases, and also to deliver drugs to metastatic sites within tissues. PMID:25270379

Programming and memory dynamics of innate leukocytes during tissue homeostasis and inflammation.

PubMed

Lee, Christina; Geng, Shuo; Zhang, Yao; Rahtes, Allison; Li, Liwu

2017-09-01

The field of innate immunity is witnessing a paradigm shift regarding "memory" and "programming" dynamics. Past studies of innate leukocytes characterized them as first responders to danger signals with no memory. However, recent findings suggest that innate leukocytes, such as monocytes and neutrophils, are capable of "memorizing" not only the chemical nature but also the history and dosages of external stimulants. As a consequence, innate leukocytes can be dynamically programmed or reprogrammed into complex inflammatory memory states. Key examples of innate leukocyte memory dynamics include the development of primed and tolerant monocytes when "programmed" with a variety of inflammatory stimulants at varying signal strengths. The development of innate leukocyte memory may have far-reaching translational implications, as programmed innate leukocytes may affect the pathogenesis of both acute and chronic inflammatory diseases. This review intends to critically discuss some of the recent studies that address this emerging concept and its implication in the pathogenesis of inflammatory diseases. © Society for Leukocyte Biology.

The mitochondria-targeted antioxidant MitoQ modulates oxidative stress, inflammation and leukocyte-endothelium interactions in leukocytes isolated from type 2 diabetic patients.

PubMed

Escribano-Lopez, Irene; Diaz-Morales, Noelia; Rovira-Llopis, Susana; de Marañon, Arantxa Martinez; Orden, Samuel; Alvarez, Angeles; Bañuls, Celia; Rocha, Milagros; Murphy, Michael P; Hernandez-Mijares, Antonio; Victor, Victor M

2016-12-01

It is not known if the mitochondria-targeted antioxidants such as mitoquinone (MitoQ) can modulate oxidative stress and leukocyte-endothelium interactions in T2D patients. We aimed to evaluate the beneficial effect of MitoQ on oxidative stress parameters and leukocyte-endothelium interactions in leukocytes of T2D patients. The study population consisted of 98 T2D patients and 71 control subjects. We assessed metabolic and anthropometric parameters, mitochondrial reactive oxygen species (ROS) production, glutathione peroxidase 1 (GPX-1), NFκB-p65, TNFα and leukocyte-endothelium interactions. Diabetic patients exhibited higher weight, BMI, waist circumference, SBP, DBP, glucose, insulin, HOMA-IR, HbA1c, triglycerides, hs-CRP and lower HDL-c with respect to controls. Mitochondrial ROS production was enhanced in T2D patients and decreased by MitoQ. The antioxidant also increased GPX-1 levels and PMN rolling velocity and decreased PMN rolling flux and PMN adhesion in T2D patients. NFκB-p65 and TNFα were augmented in T2D and were both reduced by MitoQ treatment. Our findings support that the antioxidant MitoQ has an anti-inflammatory and antioxidant action in the leukocytes of T2D patients by decreasing ROS production, leukocyte-endothelium interactions and TNFα through the action of NFκB. These data suggest that mitochondria-targeted antioxidants such as MitoQ should be investigated as a novel means of preventing cardiovascular events in T2D patients. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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…

Human leukocytic pyrogen: purification and development of a radioimmunoassay.

PubMed

Dinarello, C A; Renfer, L; Wolff, S M

1977-10-01

Leukocytic pyrogen is a small endogenous protein that mediates fever. Because of the limitations of bioassays, circulating leukocytic pyrogen has not been demonstrated during fever in humans. The pyrogen was produced in vitro after phagocytosis of staphylococci by blood monocytes. Antibody against the pyrogen was obtained from rabbits immunized with leukocytic pyrogen and the antiserum was purified by solid-phase immunoadsorbants. Purified antibody to the pyrogen was attached to activated Sepharose 4B and used in conjunction with gel filtration to purify the pyrogen. The pyrogen was labeled with 125I and further purified by gel filtration and ion-exchange chromatography. The final preparation of 125I-labeled pyrogen demonstrated a homogeneous band during isoelectric focusing and other separation procedures. With antibody to pyrogen attached to Sepharose, less than 0.1 of a rabbit pyrogenic dose of human leukocytic pyrogen inhibited the binding of 125I-labeled pyrogen to this immunoadsorbant, and this inhibition was not affected by the presence of human serum. Thus, a radioimmunoassay for human leukocytic pyrogen has been developed that may be used to detect circulating pyrogen during fever in humans.

Particle tracking acceleration via signed distance fields in direct-accelerated geometry Monte Carlo

DOE PAGES

Shriwise, Patrick C.; Davis, Andrew; Jacobson, Lucas J.; ...

2017-08-26

Computer-aided design (CAD)-based Monte Carlo radiation transport is of value to the nuclear engineering community for its ability to conduct transport on high-fidelity models of nuclear systems, but it is more computationally expensive than native geometry representations. This work describes the adaptation of a rendering data structure, the signed distance field, as a geometric query tool for accelerating CAD-based transport in the direct-accelerated geometry Monte Carlo toolkit. Demonstrations of its effectiveness are shown for several problems. The beginnings of a predictive model for the data structure's utilization based on various problem parameters is also introduced.

Leukocyte integrin activation mediates transient neutropenia after G-CSF administration

PubMed Central

Tuschong, Laura; Bauer, Thomas R.; Yau, Yu Ying; Leitman, Susan F.; Hickstein, Dennis D.

2011-01-01

After administration of granulocyte colony-stimulating factor (G-CSF), there is a marked, albeit transient, drop in circulating neutrophils. To determine the role of leukocyte integrins in this disappearance, a dog having canine leukocyte adhesion deficiency (CLAD) or CLAD dogs who had undergone gene correction either by matched littermate allogeneic transplant or autologous gene therapy were evaluated. Shortly after G-CSF administration, a dramatic, yet transient, neutropenia was observed in the control littermates. This neutropenia was not as marked in the CLAD dogs. In all instances, it was CD18+ neutrophils that preferentially egressed from the circulation. The association of CD18 with this rapid loss suggested leukocyte integrin activation after G-CSF administration. To determine the activation status of the integrin, a monoclonal antibody recognizing the activated α-subunit cation binding domain (mAb24) was used to evaluate human leukocytes after G-CSF administration. Mirroring the dramatic decrease in circulating neutrophil numbers, there was a dramatic and specific increase in the activation of the α-subunit after G-CSF expression on polymorphonuclear leukocytes. This activation, like the drop in neutrophil count, was transient. These results demonstrate that the leukocyte integrin on circulating neutrophils is transiently activated after G-CSF administration and mediates the transient neutropenia observed after G-CSF administration. PMID:21844566

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.)

Defining the chemokine basis for leukocyte recruitment during viral encephalitis.

PubMed

Michlmayr, Daniela; McKimmie, Clive S; Pingen, Marieke; Haxton, Ben; Mansfield, Karen; Johnson, Nicholas; Fooks, Anthony R; Graham, Gerard J

2014-09-01

The encephalitic response to viral infection requires local chemokine production and the ensuing recruitment of immune and inflammatory leukocytes. Accordingly, chemokine receptors present themselves as plausible therapeutic targets for drugs aimed at limiting encephalitic responses. However, it remains unclear which chemokines are central to this process and whether leukocyte recruitment is important for limiting viral proliferation and survival in the brain or whether it is predominantly a driver of coincident inflammatory pathogenesis. Here we examine chemokine expression and leukocyte recruitment in the context of avirulent and virulent Semliki Forest virus (SFV) as well as West Nile virus infection and demonstrate rapid and robust expression of a variety of inflammatory CC and CXC chemokines in all models. On this basis, we define a chemokine axis involved in leukocyte recruitment to the encephalitic brain during SFV infection. CXCR3 is the most active; CCR2 is also active but less so, and CCR5 plays only a modest role in leukocyte recruitment. Importantly, inhibition of each of these receptors individually and the resulting suppression of leukocyte recruitment to the infected brain have no effect on viral titer or survival following infection with a virulent SFV strain. In contrast, simultaneous blockade of CXCR3 and CCR2 results in significantly reduced mortality in response to virulent SFV infection. In summary, therefore, our data provide an unprecedented level of insight into chemokine orchestration of leukocyte recruitment in viral encephalitis. Our data also highlight CXCR3 and CCR2 as possible therapeutic targets for limiting inflammatory damage in response to viral infection of the brain. Brain inflammation (encephalitis) in response to viral infection can lead to severe illness and even death. This therefore represents an important clinical problem and one that requires the development of new therapeutic approaches. Central to the pathogenesis of

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.

Symplectic multiparticle tracking model for self-consistent space-charge simulation

DOE PAGES

Qiang, Ji

2017-01-23

Symplectic tracking is important in accelerator beam dynamics simulation. So far, to the best of our knowledge, there is no self-consistent symplectic space-charge tracking model available in the accelerator community. In this paper, we present a two-dimensional and a three-dimensional symplectic multiparticle spectral model for space-charge tracking simulation. This model includes both the effect from external fields and the effect of self-consistent space-charge fields using a split-operator method. Such a model preserves the phase space structure and shows much less numerical emittance growth than the particle-in-cell model in the illustrative examples.

Symplectic multiparticle tracking model for self-consistent space-charge simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qiang, Ji

Symplectic tracking is important in accelerator beam dynamics simulation. So far, to the best of our knowledge, there is no self-consistent symplectic space-charge tracking model available in the accelerator community. In this paper, we present a two-dimensional and a three-dimensional symplectic multiparticle spectral model for space-charge tracking simulation. This model includes both the effect from external fields and the effect of self-consistent space-charge fields using a split-operator method. Such a model preserves the phase space structure and shows much less numerical emittance growth than the particle-in-cell model in the illustrative examples.

Leukocyte Trafficking in Cardiovascular Disease: Insights from Experimental Models.

PubMed

Jones, Daniel P; True, Harry D; Patel, Jyoti

2017-01-01

Chemokine-induced leukocyte migration into the vessel wall is an early pathological event in the progression of atherosclerosis, the underlying cause of myocardial infarction. The immune-inflammatory response, mediated by both the innate and adaptive immune cells, is involved in the initiation, recruitment, and resolution phases of cardiovascular disease progression. Activation of leukocytes via inflammatory mediators such as chemokines, cytokines, and adhesion molecules is instrumental in these processes. In this review, we highlight leukocyte activation with the main focus being on the mechanisms of chemokine-mediated recruitment in atherosclerosis and the response postmyocardial infarction with key examples from experimental models of cardiovascular inflammation.

Contour Detection of Leukocyte Cell Nucleus Using Morphological Image

NASA Astrophysics Data System (ADS)

Supriyanti, R.; Satrio, G. P.; Ramadhani, Y.; Siswandari, W.

2017-04-01

Leukocytes are blood cells that do not contain color pigments. Leukocyte function to the tool body’s defenses. Abnormal forms of leukocytes can be a sign of serious diseases such example is leukemia. Most laboratories still use cell morphology examination to assist the diagnosis of illness associated with white blood cells such example is leukemia because of limited resources, both infrastructure, and human resources as happens in developing nations, such as Indonesia. This examination is less expensive and quicker process. However, morphological review requires the expertise of a specialist clinical pathology were limited. This process is sometimes less valid cause in some cases trying to differentiate morphology blast cells into the type of myoblasts, lymphoblast, monoblast, or erythroblast thus potentially misdiagnosis. The goal of this research is to develop a detection device types of blood cells automatically as lower-priced, easy to use and accurate so that the tool can be distributed across all units in existing health services throughout Indonesia and in particular for remote areas. However, because the variables used in the identification of abnormal leukocytes are very complex, in this paper, we emphasize on the contour detection of leukocyte cell nucleus using the morphological image. The results show that this method is promising for further development.

Acute Fluoxetine Treatment Induces Slow Rolling of Leukocytes on Endothelium in Mice

PubMed Central

Herr, Nadine; Mauler, Maximilian; Witsch, Thilo; Stallmann, Daniela; Schmitt, Stefanie; Mezger, Julius; Bode, Christoph; Duerschmied, Daniel

2014-01-01

Objective Activated platelets release serotonin at sites of inflammation where it acts as inflammatory mediator and enhances recruitment of neutrophils. Chronic treatment with selective serotonin reuptake inhibitors (SSRI) depletes the serotonin storage pool in platelets, leading to reduced leukocyte recruitment in murine experiments. Here, we examined the direct and acute effects of SSRI on leukocyte recruitment in murine peritonitis. Methods C57Bl/6 and Tph1−/− (Tryptophan hydroxylase1) mice underwent acute treatment with the SSRI fluoxetine or vehicle. Serotonin concentrations were measured by ELISA. Leukocyte rolling and adhesion on endothelium was analyzed by intravital microscopy in mesentery venules with and without lipopolysaccharide challenge. Leukocyte extravasation in sterile peritonitis was measured by flow cytometry of abdominal lavage fluid. Results Plasma serotonin levels were elevated 2 hours after fluoxetine treatment (0.70±0.1 µg/ml versus 0.27±0.1, p = 0.03, n = 14), while serum serotonin did not change. Without further stimulation, acute fluoxetine treatment increased the number of rolling leukocytes (63±8 versus 165±17/0.04 mm2min−1) and decreased their velocity (61±6 versus 28±1 µm/s, both p<0.0001, n = 10). In Tph1−/− mice leukocyte rolling was not significantly influenced by acute fluoxetine treatment. Stimulation with lipopolysaccharide decreased rolling velocity and induced leukocyte adhesion, which was enhanced after fluoxetine pretreatment (27±3 versus 36±2/0.04 mm2, p = 0.008, n = 10). Leukocyte extravasation in sterile peritonitis, however, was not affected by acute fluoxetine treatment. Conclusions Acute fluoxetine treatment increased plasma serotonin concentrations and promoted leukocyte-endothelial interactions in-vivo, suggesting that serotonin is a promoter of acute inflammation. E-selectin was upregulated on endothelial cells in the presence of serotonin, possibly explaining the observed

Ischemia-reperfusion injury in the isolated rat lung. Role of flow and endogenous leukocytes.

PubMed

Seibert, A F; Haynes, J; Taylor, A

1993-02-01

Microvascular lung injury caused by ischemia-reperfusion (IR) may occur via leukocyte-dependent and leukocyte-independent pathways. Leukocyte-endothelial adhesion may be a rate-limiting step in IR lung injury. Leukocyte adhesion to microvascular endothelium occurs when the attractant forces between leukocyte and endothelium are greater than the kinetic energy of the leukocyte and the vascular wall shear rate. We hypothesized (1) that isolated, buffer-perfused rat lungs are not free of endogenous leukocytes, (2) that endogenous leukocytes contribute to IR-induced microvascular injury as measured by the capillary filtration coefficient (Kfc), and (3) that a reduction of perfusate flow rate would potentiate leukocyte-dependent IR injury. Sixty lungs were divided into four groups: (1) low-flow controls, (2) high-flow controls, (3) low-flow IR, and (4) high-flow IR. Microvascular injury was linearly related to baseline perfusate leukocyte concentrations at both low (r = 0.78) and high (r = 0.82) flow rates. Kfc in the high-flow IR group (0.58 +/- 0.03 ml/min/cm H2O/100 g) was less (p < 0.05) than Kfc in the low-flow IR group (0.82 +/- 0.07), and in both groups Kfc values were significantly greater than low-flow (0.34 +/- 0.03) and high-flow (0.31 +/- 0.01) control Kfc values after 75 min. Retention of leukocytes in the lung, evaluated by a tissue myeloperoxidase assay, was greatest in the low-flow IR group. We conclude (1) that isolated, buffer-perfused rat lungs contain significant quantities of leukocytes and that these leukocytes contribute to IR lung injury, and (2) that IR-induced microvascular injury is potentiated by low flow.

Pathophysiology of Relapsing Fever: Interaction of Borrelia Spirochetes with Blood Mononuclear Leukocytes Causes Production of Leukocytic Pyrogen and Tissue Thromboplastin.

DTIC Science & Technology

1980-12-10

AD-A093 BN6 CASE WESTERN RESERVE UNIV CLEVELAND OH DEPT OF MEDICINE FIG 6/5 PAT1OPHYSIOLOGY OF RELAPSING FEVERS INTERACTION OF BORRELtA SPI-ETC(U...NUMBER 4 Pathophysiology of Relapsing Fever : Interaction of Borrelia Spirochetes 0 with Blood Mononuclear Leukocytes Causes Production of Leukocytic...Relapsing fever caused by Borrelia spirochetes is characterized by episodes of spirochetemia, fever , and disseminated intravascular coagu- lation (DIC

In vivo imaging of leukocyte recruitment to glomeruli in mice using intravital microscopy.

PubMed

Kitching, A Richard; Kuligowski, Michael P; Hickey, Michael J

2009-01-01

Leukocytes mediate some forms of glomerulonephritis, particularly severe proliferative and crescentic forms. The renal glomerulus is one of the few sites within the microvasculature in which leukocyte recruitment occurs in capillaries. However, due to the difficulty of directly visualising the glomerulus, the mechanisms of leukocyte recruitment to glomerular capillaries are poorly understood. To overcome this, a murine kidney can be rendered hydronephrotic, by ligating one ureter, and allowing the mouse to rest for 12 weeks. This allows the visualisation of the glomerular microvasculature during inflammatory responses. In inflammation, in this example induced by anti-glomerular basement membrane (GBM) antibody, leukocytes can be observed undergoing adhesion in glomerular capillaries using intravital microscopy. Leukocyte adhesion can be quantitated using this approach. An observation protocol involving few, limited periods of epifluorescence avoids phototoxicity-induced leukocyte recruitment. The process of hydronephrosis does not alter the ability of anti-GBM-antibody to induce a glomerular inflammatory response. This approach allows detailed investigation of the mechanisms of leukocyte recruitment within glomeruli.

[Approaches to the immunological problems of leukocyte transfusions].

PubMed

Gualde, N; Malinvaud, G; Gaillard, S

1975-01-01

51 leukocyte transfusions from healthy donors and 3 from chronic myelogenous leukemia were given to 16 patients with acute leukemia and 4 with aplasia. During 14 transfusions we have observed clinicals reactions which are of immunological origin. The part of the transfusions and of the pregnancies in the presence of antibodies is argued. The necessity of utilisation of HL-A compatible donors during leukocyte transfusions is asserted.

Does MRI scan acceleration affect power to track brain change?

PubMed

Ching, Christopher R K; Hua, Xue; Hibar, Derrek P; Ward, Chadwick P; Gunter, Jeffrey L; Bernstein, Matt A; Jack, Clifford R; Weiner, Michael W; Thompson, Paul M

2015-01-01

The Alzheimer's Disease Neuroimaging Initiative recently implemented accelerated T1-weighted structural imaging to reduce scan times. Faster scans may reduce study costs and patient attrition by accommodating people who cannot tolerate long scan sessions. However, little is known about how scan acceleration affects the power to detect longitudinal brain change. Using tensor-based morphometry, no significant difference was detected in numerical summaries of atrophy rates from accelerated and nonaccelerated scans in subgroups of patients with Alzheimer's disease, early or late mild cognitive impairment, or healthy controls over a 6- and 12-month scan interval. Whole-brain voxelwise mapping analyses revealed some apparent regional differences in 6-month atrophy rates when comparing all subjects irrespective of diagnosis (n = 345). No such whole-brain difference was detected for the 12-month scan interval (n = 156). Effect sizes for structural brain changes were not detectably different in accelerated versus nonaccelerated data. Scan acceleration may influence brain measures but has minimal effects on tensor-based morphometry-derived atrophy measures, at least over the 6- and 12-month intervals examined here. Copyright © 2015 Elsevier Inc. All rights reserved.

Leukocyte Trafficking in Cardiovascular Disease: Insights from Experimental Models

PubMed Central

2017-01-01

Chemokine-induced leukocyte migration into the vessel wall is an early pathological event in the progression of atherosclerosis, the underlying cause of myocardial infarction. The immune-inflammatory response, mediated by both the innate and adaptive immune cells, is involved in the initiation, recruitment, and resolution phases of cardiovascular disease progression. Activation of leukocytes via inflammatory mediators such as chemokines, cytokines, and adhesion molecules is instrumental in these processes. In this review, we highlight leukocyte activation with the main focus being on the mechanisms of chemokine-mediated recruitment in atherosclerosis and the response postmyocardial infarction with key examples from experimental models of cardiovascular inflammation. PMID:28465628

Relationship of Stress, Leukocyte Functions and Acute Ulcerative Gingivitis.

DTIC Science & Technology

1982-10-22

IONAL 1jjl (I Y AN[)AAU> I,)(, 4 •. . . . .i -AD (Report Number 3 , Lf) RELATIONSHIP OF STRESS, LEUKOCYTE FUNCTION AND ACUTE ULCERATIVE GINGIVITIS...AIk £It. KEY WORDS (C~mntm. a reers old. A *1acoa and Identit by block number) Acute Necrotic Ulcerative Gingivitis (ANUG)), Stress 4 Leukocyte

PET/CT with 18F-FDG- and 18F-FBEM-labeled leukocytes for metabolic activity and leukocyte recruitment monitoring in a mouse model of pulmonary fibrosis.

PubMed

Bondue, Benjamin; Sherer, Félicie; Van Simaeys, Gaetan; Doumont, Gilles; Egrise, Dominique; Yakoub, Yousof; Huaux, François; Parmentier, Marc; Rorive, Sandrine; Sauvage, Sébastien; Lacroix, Simon; Vosters, Olivier; De Vuyst, Paul; Goldman, Serge

2015-01-01

Idiopathic pulmonary fibrosis is characterized by a progressive and irreversible respiratory failure. Validated noninvasive methods able to assess disease activity are essential for prognostic purposes as well as for the evaluation of emerging antifibrotic treatments. C57BL/6 mice were used in a murine model of pulmonary fibrosis induced by an intratracheal instillation of bleomycin (control mice were instilled with a saline solution). At different times after instillation, PET/CT with (18)F-FDG- or (18)F-4-fluorobenzamido-N-ethylamino-maleimide ((18)F-FBEM)-labeled leukocytes was performed to assess metabolic activity and leukocyte recruitment, respectively. In bleomycin-treated mice, a higher metabolic activity was measured on (18)F-FDG PET/CT scans from day 7 to day 24 after instillation, with a peak of activity measured at day 14. Of note, lung mean standardized uptake values correlated with bleomycin doses, histologic score of fibrosis, lung hydroxyproline content, and weight loss. Moreover, during the inflammatory phase of the model (day 7), but not the fibrotic phase (day 23), bleomycin-treated mice presented with an enhanced leukocyte recruitment as assessed by (18)F-FBEM-labeled leukocyte PET/CT. Autoradiographic analysis of lung sections and CD45 immunostaining confirm the higher and early recruitment of leukocytes in bleomycin-treated mice, compared with control mice. (18)F-FDG- and (18)F-FBEM-labeled leukocyte PET/CT enable monitoring of metabolic activity and leukocyte recruitment in a mouse model of pulmonary fibrosis. Implications for preclinical evaluation of antifibrotic therapy are expected. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Comparison of Cytomegalovirus Loads in Plasma and Leukocytes of Patients with Cytomegalovirus Retinitis

PubMed Central

Jabs, Douglas A.; Forman, Michael; Enger, Cheryl; Jackson, J. Brooks

1999-01-01

Cytomegalovirus (CMV) DNA loads in paired leukocyte and plasma samples from 199 patient visits by 66 patients with CMV retinitis were determined. Leukocyte CMV load determinations had a greater range of values (mean, 24,587 copies/106 leukocytes; maximum, 539,000) than did plasma CMV load determinations (mean, 10,302 copies/ml; maximum, 386,000), and leukocyte viral loads were detectable in a greater proportion of patients at the time of diagnosis of CMV retinitis prior to initiation of anti-CMV therapy (82%) than were plasma viral loads (64%) (P = 0.0078). Agreement with CMV blood cultures was slightly better for plasma (κ = 0.68) than for leukocytes (κ = 0.53), due to a greater proportion of patients with detectable viral loads in leukocytes having negative blood cultures. PMID:10203500

Improved receiver arrays and optimized parallel imaging accelerations applied to time-resolved 3D fluoroscopically tracked peripheral runoff CE-MRA.

PubMed

Weavers, Paul T; Borisch, Eric A; Hulshizer, Tom C; Rossman, Phillip J; Young, Phillip M; Johnson, Casey P; McKay, Jessica; Cline, Christopher C; Riederer, Stephen J

2016-04-01

Three-station stepping-table time-resolved 3D contrast-enhanced magnetic resonance angiography has conflicting demands in the need to limit acquisition time in proximal stations to match the speed of the advancing contrast bolus and in the distal-most station to avoid venous contamination while still providing clinically useful spatial resolution. This work describes improved receiver coil arrays which address this issue by allowing increased acceleration factors, providing increased spatial resolution per unit time. Receiver coil arrays were constructed for each station (pelvis, thigh, calf) and then integrated into a 48-element array for three-station peripheral CE-MRA. Coil element sizes and array configurations for these three stations were designed to improve SENSE-type parallel imaging taking advantage of an increase in coil count for all stations versus the previous 32 channel capability. At each station either acceleration apportionment or optimal CAIPIRINHA selection was used to choose the optimum acceleration parameters for each subject. Results were evaluated in both single- and multi-station studies. Single-station studies showed that SENSE acceleration in the thigh station could be readily increased from R=8 to R=10, allowing reduction of the frame time from 2.5 to 2.1 s to better image the typically rapidly advancing bolus at this station. Similarly, the improved coil array for the calf station permitted acceleration increase from R=8 to R=12, providing a 4.0 vs. 5.2 s frame time. Results in three-station studies suggest an improved ability to track the contrast bolus in peripheral CE-MRA. Modified receiver coil arrays and individualized parameter optimization have been used to provide improved acceleration at all stations in multi-station peripheral CE-MRA and provide high spatial resolution with frame times as short as 2.1 s. Copyright © 2015 Elsevier Inc. All rights reserved.

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

Fine-grained leukocyte classification with deep residual learning for microscopic images.

PubMed

Qin, Feiwei; Gao, Nannan; Peng, Yong; Wu, Zizhao; Shen, Shuying; Grudtsin, Artur

2018-08-01

Leukocyte classification and cytometry have wide applications in medical domain, previous researches usually exploit machine learning techniques to classify leukocytes automatically. However, constrained by the past development of machine learning techniques, for example, extracting distinctive features from raw microscopic images are difficult, the widely used SVM classifier only has relative few parameters to tune, these methods cannot efficiently handle fine-grained classification cases when the white blood cells have up to 40 categories. Based on deep learning theory, a systematic study is conducted on finer leukocyte classification in this paper. A deep residual neural network based leukocyte classifier is constructed at first, which can imitate the domain expert's cell recognition process, and extract salient features robustly and automatically. Then the deep neural network classifier's topology is adjusted according to the prior knowledge of white blood cell test. After that the microscopic image dataset with almost one hundred thousand labeled leukocytes belonging to 40 categories is built, and combined training strategies are adopted to make the designed classifier has good generalization ability. The proposed deep residual neural network based classifier was tested on microscopic image dataset with 40 leukocyte categories. It achieves top-1 accuracy of 77.80%, top-5 accuracy of 98.75% during the training procedure. The average accuracy on the test set is nearly 76.84%. This paper presents a fine-grained leukocyte classification method for microscopic images, based on deep residual learning theory and medical domain knowledge. Experimental results validate the feasibility and effectiveness of our approach. Extended experiments support that the fine-grained leukocyte classifier could be used in real medical applications, assist doctors in diagnosing diseases, reduce human power significantly. Copyright © 2018 Elsevier B.V. All rights reserved.

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

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

In vitro phagocytosis of several Candida berkhout species by murine leukocytes.

PubMed

Fontenla de Petrino, S E; Bibas Bonet de Jorrat, M E; Sirena, A

1985-03-01

In vitro phagocytosis of thirteen Candida berkhout species by rat leukocytes was studied to assess a possible correlation between pathogenicity and phagocytosis Yeast-leukocyte suspensions were mixed up for 3 h and phagocytic index, germ-tube formation and leukocyte candidacidal activity were evaluated. Highest values for phagocytosis were reached in all cases at the end of the first hour. Leukocyte candidacidal activity was absent. Only C. albicans produced germ-tubes. The various phagocytosis indices were determined depending on the Candida species assayed. Under these conditions, the more pathogenic species presented the lower indices of phagocytosis. It is determined that the in vitro phagocytic index may bear a close relationship with the pathogenicity of the Candida berkhout.

Peritoneal dialysis solution attenuates microvascular leukocyte adhesion induced by nitric oxide synthesis inhibition.

PubMed

White, R; Ram, S

1996-01-01

In the mesenteric microcirculation, inhibition of nitric oxide (NO) synthesis results in an inflammatory response through increased leukocyte adherence to the microvascular postcapillary venular endothelium. Recent studies have demonstrated that elevated concentrations of endogenous NO synthesis inhibitors are present in renal failure. How peritoneal dialysis solutions may affect leukocyte-endothelial interactions during inflammation induced by NO synthesis inhibition has been previously unknown. Using in vivo intravital microscopy of the rat mesenteric postcapillary venules, microvascular leukocyte adherence was quantitated during baseline conditions in which the mesentery was superfused with a buffer solution, followed by the superfusion of a NO synthesis inhibitor NG-nitro-L-ARGININE methyl ester (L-NAME) added to the buffer, followed by 4.25% Dianeal (4.25% D). When compared to baseline, L-NAME increased the mean number of adherent leukocytes by fivefold (2.2 +/- 0.9 vs 11.6 +/- 3.6 leukocytes/100 microns venule/10 min, p < 0.05), while 4.25% D quickly reversed the L-NAME-induced inflammatory response, returning the number of adherent leukocytes back to baseline values (11.6 +/- 3.6 vs 2.4 +/- 1.3 leukocytes/100 microns venule/ 10 min, p < 0.05). These results confirm that NO synthesis inhibition induces inflammation in mesenteric postcapillary venules. Superfusion of 4.25% D reverses leukocyte adhesion induced by NO synthesis inhibition. Thus, a standard peritoneal dialysis solution (4.25% D) reverses the leukocyte-adhesive effects of NO synthesis inhibition in the mesenteric microcirculation.

Improved survival of newborns receiving leukocyte transfusions for sepsis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cairo, M.S.; Rucker, R.; Bennetts, G.A.

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 weremore » 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.« less

Contribution of Human Lung Parenchyma and Leukocyte Influx to Oxidative Stress and Immune System-Mediated Pathology following Nipah Virus Infection

PubMed Central

Escaffre, Olivier; Saito, Tais B.; Juelich, Terry L.; Ikegami, Tetsuro; Smith, Jennifer K.; Perez, David D.; Atkins, Colm; Levine, Corri B.; Huante, Matthew B.; Nusbaum, Rebecca J.; Endsley, Janice J.

2017-01-01

ABSTRACT Nipah virus (NiV) is a zoonotic emerging paramyxovirus that can cause fatal respiratory illness or encephalitis in humans. Despite many efforts, the molecular mechanisms of NiV-induced acute lung injury (ALI) remain unclear. We previously showed that NiV replicates to high titers in human lung grafts in NOD-SCID/γ mice, resulting in a robust inflammatory response. Interestingly, these mice can undergo human immune system reconstitution by the bone marrow, liver, and thymus (BLT) reconstitution method, in addition to lung tissue engraftment, giving altogether a realistic model to study human respiratory viral infections. Here, we characterized NiV Bangladesh strain (NiV-B) infection of human lung grafts from human immune system-reconstituted mice in order to identify the overall effect of immune cells on NiV pathogenesis of the lung. We show that NiV-B replicated to high titers in human lung grafts and caused similar cytopathic effects irrespective of the presence of human leukocytes in mice. However, the human immune system interfered with virus spread across lung grafts, responded to infection by leukocyte migration to small airways and alveoli of the lung grafts, and accelerated oxidative stress in lung grafts. In addition, the presence of human leukocytes increased the expression of cytokines and chemokines that regulate inflammatory influx to sites of infection and tissue damage. These results advance our understanding of how the immune system limits NiV dissemination and contributes to ALI and inform efforts to identify therapeutic targets. IMPORTANCE Nipah virus (NiV) is an emerging paramyxovirus that can cause a lethal respiratory and neurological disease in humans. Only limited data are available on NiV pathogenesis in the human lung, and the relative contribution of the innate immune response and NiV to acute lung injury (ALI) is still unknown. Using human lung grafts in a human immune system-reconstituted mouse model, we showed that the Ni

Occult purulent pericarditis detected by indium-111 leukocyte imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenberg, M.L.; Niebulski, H.I.; Uretsky, B.F.

1984-05-01

Leukocyte imaging with indium-111 is a relatively new technique which, to this point in time, has been discussed almost exclusively in the radiologic literature. Although this procedure has been used mainly to detect intra-abdominal infection, the thorax is routinely imaged along with the abdomen, and therefore detection of cardiac disease may be feasible. This case report is of a young woman after liver transplantation who developed occult purulent pericarditis initially detected by a leukocyte scan with indium-111. This case demonstrates that striking pericardial uptake on a whole-body indium-111 leukocyte scan can occur with purulent pericarditis, and it reemphasizes how insidiouslymore » purulent pericarditis may present in an immunosuppressed patient.« less

Fast Track Option: An Accelerated Associate's Degree Program.

ERIC Educational Resources Information Center

Price, J. Randall

1998-01-01

Alternative instructional delivery options such as self-paced and flexible enrollment courses are designed to increase enrollment, promote retention, and encourage student success without lowering academic standards. The Fast Track Associate's Degree Program, developed by a team of faculty, staff, and administrators at Richland Community College,…

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maurer, A.H.; Millmond, S.H.; Knight, L.C.

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,more » and absence of bone landmarks, which made it difficult to differentiate soft tissue from bone infection.« less

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

Hug tightly and say goodbye: role of endothelial ICAM-1 in leukocyte transmigration.

PubMed

Rahman, Arshad; Fazal, Fabeha

2009-04-01

Stable adhesion of leukocytes to endothelium is crucial for transendothelial migration (TEM) of leukocytes evoked during inflammatory responses, immune surveillance, and homing and mobilization of hematopoietic progenitor cells. The basis of stable adhesion involves expression of intercellular adhesion molecule-1 (ICAM-1), an inducible endothelial adhesive protein that serves as a counter-receptor for beta(2)-integrins on leukocytes. Interaction of ICAM-1 with beta(2)-integrins enables leukocytes to adhere firmly to the vascular endothelium and subsequently, to migrate across the endothelial barrier. The emerging paradigm is that ICAM-1, in addition to firmly capturing leukocytes, triggers intracellular signaling events that may contribute to active participation of the endothelium in facilitating the TEM of adherent leukocytes. The nature, duration, and intensity of ICAM-1-dependent signaling events may contribute to the determination of the route (paracellular vs. transcellular) of leukocyte passage; these aspects of ICAM-1 signaling may in turn be influenced by density and distribution of ICAM-1 on the endothelial cell surface, the source of endothelial cells it is present on, and the type of leukocytes with which it is engaged. This review summarizes our current understanding of the "ICAM-1 paradigm" of TEM with an emphasis on the signaling events mediating ICAM-1 expression and activated by ICAM-1 engagement in endothelial cells.

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.

Symplectic multi-particle tracking on GPUs

NASA Astrophysics Data System (ADS)

Liu, Zhicong; Qiang, Ji

2018-05-01

A symplectic multi-particle tracking model is implemented on the Graphic Processing Units (GPUs) using the Compute Unified Device Architecture (CUDA) language. The symplectic tracking model can preserve phase space structure and reduce non-physical effects in long term simulation, which is important for beam property evaluation in particle accelerators. Though this model is computationally expensive, it is very suitable for parallelization and can be accelerated significantly by using GPUs. In this paper, we optimized the implementation of the symplectic tracking model on both single GPU and multiple GPUs. Using a single GPU processor, the code achieves a factor of 2-10 speedup for a range of problem sizes compared with the time on a single state-of-the-art Central Processing Unit (CPU) node with similar power consumption and semiconductor technology. It also shows good scalability on a multi-GPU cluster at Oak Ridge Leadership Computing Facility. In an application to beam dynamics simulation, the GPU implementation helps save more than a factor of two total computing time in comparison to the CPU implementation.

Traffic of leukocytes in microfluidic channels with rectangular and rounded cross-sections.

PubMed

Yang, Xiaoxi; Forouzan, Omid; Burns, Jennie M; Shevkoplyas, Sergey S

2011-10-07

Traffic of leukocytes in microvascular networks (particularly through arteriolar bifurcations and venular convergences) affects the dynamics of capillary blood flow, initiation of leukocyte adhesion during inflammation, and localization and development of atherosclerotic plaques in vivo. Recently, a growing research effort has been focused on fabricating microvascular networks comprising artificial vessels with more realistic, rounded cross-sections. This paper investigated the impact of the cross-sectional geometry of microchannels on the traffic of leukocytes flowing with human whole blood through a non-symmetrical bifurcation that consisted of a 50 μm mother channel bifurcating into 30 μm and 50 μm daughter branches. Two versions of the same bifurcation comprising microchannels with rectangular and rounded cross-sections were fabricated using conventional multi-layer photolithography to produce rectangular microchannles that were then rounded in situ using a recently developed method of liquid PDMS/air bubble injection. For microchannels with rounded cross-sections, about two-thirds of marginated leukocytes traveling along a path in the top plane of the bifurcation entered the smallest 30 μm daughter branch. This distribution was reversed in microchannels with rectangular cross-sections--the majority of leukocytes traveling along a similar path continued to follow the 50 μm microchannels after the bifurcation. This dramatic difference in the distribution of leukocyte traffic among the branches of the bifurcation can be explained by preferential margination of leukocytes towards the corners of the 50 μm mother microchannels with rectangular cross-sections, and by the additional hindrance to leukocyte entry created by the sharp transition from the 50 μm mother microchannel to the 30 μm daughter branch at the intersection. The results of this study suggest that the trajectories of marginated leukocytes passing through non-symmetrical bifurcations are

Meisoindigo, but not its core chemical structure indirubin, inhibits zebrafish interstitial leukocyte chemotactic migration.

PubMed

Ye, Baixin; Xiong, Xiaoxing; Deng, Xu; Gu, Lijuan; Wang, Qiongyu; Zeng, Zhi; Gao, Xiang; Gao, Qingping; Wang, Yueying

2017-12-01

Inflammatory disease is a big threat to human health. Leukocyte chemotactic migration is required for efficient inflammatory response. Inhibition of leukocyte chemotactic migration to the inflammatory site has been shown to provide therapeutic targets for treating inflammatory diseases. Our study was designed to discover effective and safe compounds that can inhibit leukocyte chemotactic migration, thus providing possible novel therapeutic strategy for treating inflammatory diseases. In this study, we used transgenic zebrafish model (Tg:zlyz-EGFP line) to visualize the process of leukocyte chemotactic migration. Then, we used this model to screen the hit compound and evaluate its biological activity on leukocyte chemotactic migration. Furthermore, western blot analysis was performed to evaluate the effect of the hit compound on the AKT or ERK-mediated pathway, which plays an important role in leukocyte chemotactic migration. In this study, using zebrafish-based chemical screening, we identified that the hit compound meisoindigo (25 μM, 50 μM, 75 μM) can significantly inhibit zebrafish leukocyte chemotactic migration in a dose-dependent manner (p = 0.01, p = 0.0006, p < 0.0001). Also, we found that meisoindigo did not affect the process of leukocyte reverse migration (p = 0.43). Furthermore, our results unexpectedly showed that indirubin, the core structure of meisoindigo, had no significant effect on zebrafish leukocyte chemotactic migration (p = 0.6001). Additionally, our results revealed that meisoindigo exerts no effect on the Akt or Erk-mediated signalling pathway. Our results suggest that meisoindigo, but not indirubin, is effective for inhibiting leukocyte chemotactic migration, thus providing a potential therapeutic agent for treating inflammatory diseases.

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.

Chemokine Ligand 20: A Signal for Leukocyte Recruitment During Human Ovulation?

PubMed Central

Al-Alem, Linah; Puttabyatappa, Muraly; Rosewell, Kathy; Brännström, Mats; Akin, James; Boldt, Jeffrey; Muse, Ken

2015-01-01

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

House Dust Endotoxin and Peripheral Leukocyte Counts: Results from Two Large Epidemiologic Studies.

PubMed

Fessler, Michael B; Carnes, Megan U; Salo, Päivi M; Wilkerson, Jesse; Cohn, Richard D; King, Debra; Hoppin, Jane A; Sandler, Dale P; Travlos, Greg; London, Stephanie; Thorne, Peter; Zeldin, Darryl

2017-05-31

The peripheral leukocyte count is a biomarker of inflammation and is associated with human all-cause mortality. Although causes of acute leukocytosis are well-described, chronic environmental determinants of leukocyte number are less well understood. We investigated the relationship between house dust endotoxin concentration and peripheral leukocyte counts in human subjects. The endotoxin–leukocyte relationship was evaluated by linear regression in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 (n=6,254) and the Agricultural Lung Health Study (ALHS; n=1,708). In the ALHS, we tested for a gene [Toll-like Receptor 4 ( TLR4 ), encoding the endotoxin receptor]-by-environment interaction in the endotoxin–leukocyte relationship using regression models with an interaction term. There is a statistically significant, positive association between endotoxin concentration and total leukocyte number [estimated change, 0.186×10 3 /μL (95% CI: 0.070, 0.301×10 3 /μL) per 10-fold change in endotoxin; p=0.004) in the NHANES. Similar positive associations were found for monocytes, lymphocytes, and neutrophils. Stratified analyses revealed possible effect modification by asthma and chronic obstructive pulmonary disease. We observed similar associations in the ALHS. For total leukocytes, there was suggestive evidence in the ALHS of a gene-by-environment interaction for minor allele carrier status at the TLR4 haplotype defined by rs4986790 and rs4986791 (interaction p=0.15). This is, to our knowledge, the first report of an association between house dust endotoxin and leukocyte count in a national survey. The finding was replicated in a farming population. Peripheral leukocyte count may be influenced by residential endotoxin exposure in diverse settings. https://doi.org/10.1289/EHP661.

House Dust Endotoxin and Peripheral Leukocyte Counts: Results from Two Large Epidemiologic Studies

PubMed Central

Carnes, Megan U.; Salo, Päivi M.; Wilkerson, Jesse; Cohn, Richard D.; King, Debra; Hoppin, Jane A.; Sandler, Dale P.; Travlos, Greg; London, Stephanie J.; Thorne, Peter S.; Zeldin, Darryl C.

2017-01-01

Background: The peripheral leukocyte count is a biomarker of inflammation and is associated with human all-cause mortality. Although causes of acute leukocytosis are well-described, chronic environmental determinants of leukocyte number are less well understood. Objectives: We investigated the relationship between house dust endotoxin concentration and peripheral leukocyte counts in human subjects. Methods: The endotoxin–leukocyte relationship was evaluated by linear regression in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 (n=6,254) and the Agricultural Lung Health Study (ALHS; n=1,708). In the ALHS, we tested for a gene [Toll-like Receptor 4 (TLR4), encoding the endotoxin receptor]-by-environment interaction in the endotoxin–leukocyte relationship using regression models with an interaction term. Results: There is a statistically significant, positive association between endotoxin concentration and total leukocyte number [estimated change, 0.186×103/μL (95% CI: 0.070, 0.301×103/μL) per 10-fold change in endotoxin; p=0.004) in the NHANES. Similar positive associations were found for monocytes, lymphocytes, and neutrophils. Stratified analyses revealed possible effect modification by asthma and chronic obstructive pulmonary disease. We observed similar associations in the ALHS. For total leukocytes, there was suggestive evidence in the ALHS of a gene-by-environment interaction for minor allele carrier status at the TLR4 haplotype defined by rs4986790 and rs4986791 (interaction p=0.15). Conclusions: This is, to our knowledge, the first report of an association between house dust endotoxin and leukocyte count in a national survey. The finding was replicated in a farming population. Peripheral leukocyte count may be influenced by residential endotoxin exposure in diverse settings. https://doi.org/10.1289/EHP661 PMID:28599265

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.

Energy Tracking Software Platform

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryan Davis; Nathan Bird; Rebecca Birx

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 helpmore » 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.« less

Correlation of track irregularities and vehicle responses based on measured data

NASA Astrophysics Data System (ADS)

Karis, Tomas; Berg, Mats; Stichel, Sebastian; Li, Martin; Thomas, Dirk; Dirks, Babette

2018-06-01

Track geometry quality and dynamic vehicle response are closely related, but do not always correspond with each other in terms of maximum values and standard deviations. This can often be seen to give poor results in analyses with correlation coefficients or regression analysis. Measured data from both the EU project DynoTRAIN and the Swedish Green Train (Gröna Tåget) research programme is used in this paper to evaluate track-vehicle response for three vehicles. A single degree of freedom model is used as an inspiration to divide track-vehicle interaction into three parts, which are analysed in terms of correlation. One part, the vertical axle box acceleration divided by vehicle speed squared (?) and the second spatial derivative of the vertical track irregularities (?), is shown to be the weak link with lower correlation coefficients than the other parts. Future efforts should therefore be directed towards investigating the relation between axle box accelerations and track irregularity second derivatives.

Effects of Vertical Direction and Aperture Size on the Perception of Visual Acceleration.

PubMed

Mueller, Alexandra S; González, Esther G; McNorgan, Chris; Steinbach, Martin J; Timney, Brian

2016-02-06

It is not well understood whether the distance over which moving stimuli are visible affects our sensitivity to the presence of acceleration or our ability to track such stimuli. It is also uncertain whether our experience with gravity creates anisotropies in how we detect vertical acceleration and deceleration. To address these questions, we varied the vertical extent of the aperture through which we presented vertically accelerating and decelerating random dot arrays. We hypothesized that observers would better detect and pursue accelerating and decelerating stimuli that extend over larger than smaller distances. In Experiment 1, we tested the effects of vertical direction and aperture size on acceleration and deceleration detection accuracy. Results indicated that detection is better for downward motion and for large apertures, but there is no difference between vertical acceleration and deceleration detection. A control experiment revealed that our manipulation of vertical aperture size affects the ability to track vertical motion. Smooth pursuit is better (i.e., with higher peak velocities) for large apertures than for small apertures. Our findings suggest that the ability to detect vertical acceleration and deceleration varies as a function of the direction and vertical extent over which an observer can track the moving stimulus. © The Author(s) 2016.

Antiviral Activity of Intranasally Applied Human Leukocyte Interferon

PubMed Central

Greenberg, Stephen B.; Harmon, Maurice W.; Johnson, Paul E.; Couch, Robert B.

1978-01-01

Previous studies in our laboratory have demonstrated that the development of antiviral activity of human leukocyte interferon (IF) in nasal epithelial cells is time and concentration dependent and that the loss of intranasally applied human leukocyte IF is rapid. The present studies compared the activity of IF applied intranasally either by nasal drops or by a saturated cotton pledget. Adult volunteers had IF applied to an area of nasal mucosa (2 by 2 cm2) either by repeated nose drops or by a saturated cotton pledget that was applied to the nasal mucosa and left in place for 1 h. Nasal epithelial cells scraped from the area of application, as well as the control, untreated side of the same volunteers, were challenged with vesicular stomatitis virus. No significant reduction in mean virus yield was found in volunteers who received 80,000 U by nose drops. Significant reduction (P < 0.025) in mean virus yield was found in cells obtained 4 h after 80,000, 50,000, or 20,000 U was applied by cotton pledget or in volunteers pretreated with oral antihistamines prior to receiving 80,000 U by nose drops. These experiments indicate that nasal epithelial cells can be made antiviral in vivo by application of human leukocyte IF. However, practical usefulness of human leukocyte IF for prophylaxis against respiratory viral infections may depend on the method of local application. PMID:214028

Contribution of Human Lung Parenchyma and Leukocyte Influx to Oxidative Stress and Immune System-Mediated Pathology following Nipah Virus Infection.

PubMed

Escaffre, Olivier; Saito, Tais B; Juelich, Terry L; Ikegami, Tetsuro; Smith, Jennifer K; Perez, David D; Atkins, Colm; Levine, Corri B; Huante, Matthew B; Nusbaum, Rebecca J; Endsley, Janice J; Freiberg, Alexander N; Rockx, Barry

2017-08-01

Nipah virus (NiV) is a zoonotic emerging paramyxovirus that can cause fatal respiratory illness or encephalitis in humans. Despite many efforts, the molecular mechanisms of NiV-induced acute lung injury (ALI) remain unclear. We previously showed that NiV replicates to high titers in human lung grafts in NOD-SCID/γ mice, resulting in a robust inflammatory response. Interestingly, these mice can undergo human immune system reconstitution by the bone marrow, liver, and thymus (BLT) reconstitution method, in addition to lung tissue engraftment, giving altogether a realistic model to study human respiratory viral infections. Here, we characterized NiV Bangladesh strain (NiV-B) infection of human lung grafts from human immune system-reconstituted mice in order to identify the overall effect of immune cells on NiV pathogenesis of the lung. We show that NiV-B replicated to high titers in human lung grafts and caused similar cytopathic effects irrespective of the presence of human leukocytes in mice. However, the human immune system interfered with virus spread across lung grafts, responded to infection by leukocyte migration to small airways and alveoli of the lung grafts, and accelerated oxidative stress in lung grafts. In addition, the presence of human leukocytes increased the expression of cytokines and chemokines that regulate inflammatory influx to sites of infection and tissue damage. These results advance our understanding of how the immune system limits NiV dissemination and contributes to ALI and inform efforts to identify therapeutic targets. IMPORTANCE Nipah virus (NiV) is an emerging paramyxovirus that can cause a lethal respiratory and neurological disease in humans. Only limited data are available on NiV pathogenesis in the human lung, and the relative contribution of the innate immune response and NiV to acute lung injury (ALI) is still unknown. Using human lung grafts in a human immune system-reconstituted mouse model, we showed that the NiV Bangladesh

Elevated leukocyte count is associated with periodontitis in Korean adults: the 2012-2014 KNHANES.

PubMed

Kwon, Y-J; Jeon, K-J; Chung, T-H; Lee, Y-J

2017-03-01

Both an elevated leukocyte count and periodontitis share well-recognized associations with cardiometabolic diseases. This cross-sectional study aimed to identify whether the leukocyte count is associated with periodontitis in a nationally representative Korean adult population. Data from 9391 participants (3659 males and 5732 females) enrolled in 2012-2014 Korean National Health and Nutrition Examination Survey were analyzed. Leukocyte quartiles were categorized as follows: 3000 ≤ Q1 ≤ 4870, 4880 ≤ Q2 ≤5790, 5800 ≤ Q3 ≤ 6840, and 6850 ≤ Q4 ≤ 10000 cells/μl. Periodontitis was defined as scoring greater than or equal to 'code 3' in at least one site according to the WHO's Community Periodontal Index. The odds ratios (ORs) and 95% confidence intervals (95% CIs) for periodontitis in each leukocyte count quartile were calculated using multiple logistic regression analyses. The prevalence of periodontitis was directly correlated with increasing leukocyte quartiles: 19%, 20.4%, 24.3%, and 30.3%. Compared with the lowest leukocyte quartile group, the OR (95% CI) for periodontitis of the highest leukocyte quartile was 1.558 (1.285-1.891) after controlling for confounding factors. An elevated leukocyte count was positively associated with the presence of periodontitis. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palestro, C.J.; Vega, A.; Kim, C.K.

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 clinicalmore » 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.« less

Detection of murine cytomegalovirus DNA in circulating leukocytes harvested during acute infection of mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bale, J.F. Jr.; O'Neil, M.E.

1989-06-01

The authors used virus assay and in situ hybridization with a cloned fragment of the murine cytomegalovirus (MCMV) genome to study MCMV infection of circulating leukocytes harvested from 3-week-old BALB/c, C57BL/6, and C3H mice infected with MCMV intraperitoneally. Infectious virus or MCMV DNA was detected in leukocytes on days 1 through 21 of infection in BALB/c mice and on days 3 through 7 in C57BL/6 mice. On days 5 and 7, MCMV DNA or infectious virus was detected in the leukocytes of 17 (94%) of 18 BALB/c mice and 10 (59%) of 17 C57BL/6 mice. In both strains infection peakedmore » on days 5 and 7, when as many as 0.01 to 0.1% of the circulating leukocytes contained MCMV DNA. In C3H mice, however, infectious virus was rarely recovered from leukocyte fractions and MCMV DNA was detected in the circulating leukocytes of only one animal. Circulating leukocytes may have an important role in the dissemination of CMV infections in susceptible hosts.« less

A high-throughput microfluidic approach for 1000-fold leukocyte reduction of platelet-rich plasma

NASA Astrophysics Data System (ADS)

Xia, Hui; Strachan, Briony C.; Gifford, Sean C.; Shevkoplyas, Sergey S.

2016-10-01

Leukocyte reduction of donated blood products substantially reduces the risk of a number of transfusion-related complications. Current ‘leukoreduction’ filters operate by trapping leukocytes within specialized filtration material, while allowing desired blood components to pass through. However, the continuous release of inflammatory cytokines from the retained leukocytes, as well as the potential for platelet activation and clogging, are significant drawbacks of conventional ‘dead end’ filtration. To address these limitations, here we demonstrate our newly-developed ‘controlled incremental filtration’ (CIF) approach to perform high-throughput microfluidic removal of leukocytes from platelet-rich plasma (PRP) in a continuous flow regime. Leukocytes are separated from platelets within the PRP by progressively syphoning clarified PRP away from the concentrated leukocyte flowstream. Filtrate PRP collected from an optimally-designed CIF device typically showed a ~1000-fold (i.e. 99.9%) reduction in leukocyte concentration, while recovering >80% of the original platelets, at volumetric throughputs of ~1 mL/min. These results suggest that the CIF approach will enable users in many fields to now apply the advantages of microfluidic devices to particle separation, even for applications requiring macroscale flowrates.

Recipient-Matching of Passenger Leukocytes Prolongs Survival of Donor Lung Allografts in Miniature Swine

PubMed Central

Madariaga, Maria Lucia L.; Michel, Sebastian G.; La Muraglia, Glenn M.; Sihag, Smita; Leonard, David A.; Farkash, Evan A.; Colvin, Robert B.; Cetrulo, Curtis L.; Huang, Christene A.; Sachs, David H.; Madsen, Joren C.; Allan, James S.

2014-01-01

Background Allograft rejection continues to be a vexing problem in clinical lung transplantation, and the role played by passenger leukocytes in the rejection or acceptance of an organ is unclear. Here we tested whether recipient-matching of donor graft passenger leukocytes would impact graft survival in a preclinical model of orthotopic left lung transplantation. Methods In the experimental group (Group 1), donor lungs were obtained from chimeric swine, in which the passenger leukocytes (but not the parenchyma) were MHC-matched to the recipients (n=3). In the control group (Group 2), both the donor parenchyma and the passenger leukocytes were MHC-mismatched to the recipients (n = 3). Results Lungs harvested from swine previously rendered chimeric by hematopoietic stem cell transplantation using recipient-type cells showed a high degree of passenger leukocyte chimerism by immunohistochemistry and flow cytometry. The chimeric lungs containing passenger leukocytes matched to the lung recipient (Group 1) survived on average 107 days (range 80–156). Control lung allografts (Group 2) survived on average 45 days (range 29–64; p<0.05). Conclusion Our data indicate that recipient-matching of passenger leukocytes significantly prolongs lung allograft survival. PMID:25757217

An Adiabatic Phase-Matching Accelerator

DOE PAGES

Lemery, Francois; Floettmann, Klaus; Piot, Philippe; ...

2018-05-25

We present a general concept to accelerate non-relativistic charged particles. Our concept employs an adiabatically-tapered dielectric-lined waveguide which supports accelerating phase velocities for synchronous acceleration. We propose an ansatz for the transient field equations, show it satisfies Maxwell's equations under an adiabatic approximation and find excellent agreement with a finite-difference time-domain computer simulation. The fields were implemented into the particle-tracking program {\\sc astra} and we present beam dynamics results for an accelerating field with a 1-mm-wavelength and peak electric field of 100~MV/m. The numerical simulations indicate that amore » $$\\sim 200$$-keV electron beam can be accelerated to an energy of $$\\sim10$$~MeV over $$\\sim 10$$~cm. The novel scheme is also found to form electron beams with parameters of interest to a wide range of applications including, e.g., future advanced accelerators, and ultra-fast electron diffraction.« less

An Adiabatic Phase-Matching Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lemery, Francois; Floettmann, Klaus; Piot, Philippe

2017-12-22

We present a general concept to accelerate non-relativistic charged particles. Our concept employs an adiabatically-tapered dielectric-lined waveguide which supports accelerating phase velocities for synchronous acceleration. We propose an ansatz for the transient field equations, show it satisfies Maxwell's equations under an adiabatic approximation and find excellent agreement with a finite-difference time-domain computer simulation. The fields were implemented into the particle-tracking program {\\sc astra} and we present beam dynamics results for an accelerating field with a 1-mm-wavelength and peak electric field of 100~MV/m. The numerical simulations indicate that amore » $$\\sim 200$$-keV electron beam can be accelerated to an energy of $$\\sim10$$~MeV over $$\\sim 10$$~cm. The novel scheme is also found to form electron beams with parameters of interest to a wide range of applications including, e.g., future advanced accelerators, and ultra-fast electron diffraction.« less

Monitoring of benzene-induced hematotoxicity in mice by serial leukocyte counting using a microcavity array.

PubMed

Hosokawa, Masahito; Asami, Marie; Yoshino, Tomoko; Tsujimura, Noriyuki; Takahashi, Masayuki; Nakasono, Satoshi; Tanaka, Tsuyoshi; Matsunaga, Tadashi

2013-02-15

Monitoring of hematotoxicity, which requires serial blood collection, is difficult to carry out in small animals due to a lack of non-invasive, individual animal-appropriate techniques that enable enumeration of leukocyte subsets from limited amounts of whole blood. In this study, a microfluidic device equipped with a microcavity array that enables highly efficient separation of leukocytes from submicroliters of whole blood was applied for hematotoxicity monitoring in mice. The microcavity array can specifically separate leukocytes from whole blood based on differences in the size and deformability between leukocytes and other blood cells. Mouse leukocytes recovered on aligned microcavities were continuously processed for image-based immunophenotypic analysis. Our device successfully recovered almost 100% of mouse leukocytes in 0.1 μL of whole blood without the effect of serial blood collection such as changes in body weight and total leukocyte count. We assessed benzene-associated hematotoxicity in mice using this system. Mice were administered with benzene once daily and the depression of leukocyte numbers induced in individual mice was successfully monitored from tail vein blood collected every other day for 2 weeks. Serial monitoring of the leukocyte number in individual mice will contribute to the understanding of hematotoxicity and reduction of the number of animal experiment trials. Copyright © 2012 Elsevier B.V. All rights reserved.

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.

Computational Accelerator Physics. Proceedings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bisognano, J.J.; Mondelli, A.A.

1997-04-01

The sixty two papers appearing in this volume were presented at CAP96, the Computational Accelerator Physics Conference held in Williamsburg, Virginia from September 24{minus}27,1996. Science Applications International Corporation (SAIC) and the Thomas Jefferson National Accelerator Facility (Jefferson lab) jointly hosted CAP96, with financial support from the U.S. department of Energy`s Office of Energy Research and the Office of Naval reasearch. Topics ranged from descriptions of specific codes to advanced computing techniques and numerical methods. Update talks were presented on nearly all of the accelerator community`s major electromagnetic and particle tracking codes. Among all papers, thirty of them are abstracted formore » the Energy Science and Technology database.(AIP)« less

Uptake of apoptotic leukocytes by synovial lining macrophages inhibits immune complex-mediated arthritis.

PubMed

van Lent, P L; Licht, R; Dijkman, H; Holthuysen, A E; Berden, J H; van den Berg, W B

2001-11-01

Previously we have shown that synovial lining macrophages (SLMs) determine the onset of experimental immune complex-mediated arthritis (ICA). During joint inflammation, many leukocytes undergo apoptosis, and removal of leukocytes by SLMs may regulate resolution of inflammation. In this study we investigated binding and uptake of apoptotic leukocytes by SLMs and its impact on the onset of murine experimental arthritis. We used an in vitro model to evaluate phagocytosis of apoptotic cells on chemotaxis. Phagocytosis of apoptotic thymocytes resulted in a significant decrease (58%) of chemotactic activity for polymorphonuclear neutrophils (PMNs). If apoptotic cells were injected directly into a normal murine knee joint, SLMs resulted in a prominent uptake of cells. After ICA induction, electron micrographs showed that apoptotic leukocytes were evidently present in SLMs on days 1 and 2. Injection of apoptotic leukocytes into the knee joint 1 h before induction of ICA significantly inhibited PMN infiltration into the knee joint at 24 h (61% decrease). This study indicates that uptake of apoptotic leukocytes by SLM reduces chemotactic activity and inhibits the onset of experimental arthritis. These findings indicate an important mechanism in the resolution of joint inflammation.

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.

Signal-activated phospholipase regulation of leukocyte chemotaxis.

PubMed

Cathcart, Martha K

2009-04-01

Signal-activated phospholipases are a recent focus of the rapidly growing field of lipid signaling. The extent of their impact on the pathways regulating diverse cell functions is beginning to be appreciated. A critical step in inflammation is the attraction of leukocytes to injured or diseased tissue. Chemotaxis of leukocytes, a requisite process for monocyte and neutrophil extravasation from the blood into tissues, is a critical step for initiating and maintaining inflammation in both acute and chronic settings. Recent studies have identified new important and required roles for two signal-activated phospholipases A2 (PLA2) in regulating chemotaxis. The two intracellular phospholipases, cPLA2alpha (Group IVA) and iPLA2beta (Group VIA), act in parallel to provide distinct lipid mediators at different intracellular sites that are both required for leukocytes to migrate toward the chemokine monocyte chemoattractant protein-1. This review will summarize the separate roles of these phospholipases as well as what is currently known about the influence of two other classes of intracellular signal-activated phospholipases, phospholipase C and phospholipase D, in regulating chemotaxis in eukaryotic cells, but particularly in human monocytes. The contributions of these phospholipases to chemotaxis both in vitro and in vivo will be highlighted.

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

Paradoxical attenuation of leukocyte rolling in response to ischemia- reperfusion and extracorporeal blood circulation in inflamed tissue.

PubMed

Schäfer, Stephan C; Sehrt, Desiree N; Kamler, Markus; Jakob, Heinz; Lehr, Hans-Anton

2005-07-01

In contrast to acute preparations such as the exteriorized mesentery or the cremaster muscle, chronically instrumented chamber models allow one to study the microcirculation under "physiological" conditions, i.e., in the absence of trauma-induced leukocyte rolling along the venular endothelium. To underscore the importance of studying the naive microcirculation, we implanted titanium dorsal skinfold chambers in hamsters and used intravital fluorescence microscopy to study venular leukocyte rolling in response to ischemia-reperfusion injury or extracorporeal blood circulation. The experiments were performed in chambers that fulfilled all well-established criteria for a physiological microcirculation as well as in chambers that showed various extents of leukocyte rolling due to trauma, hemorrhage, or inflammation. In ideal chambers with a physiological microcirculation (<30 rolling leukocytes/mm vessel circumference in 30 s), ischemia-reperfusion injury and extracorporeal blood circulation significantly stimulated leukocyte rolling along the venular endothelium and, subsequently, firm leukocyte adhesion. In contrast, both stimuli failed to elicit leukocyte rolling in borderline chambers (30-100 leukocytes/mm), and in blatantly inflamed chambers with yet higher numbers of rolling leukocytes at baseline (>100 leukocytes/mm), we observed a paradoxical reduction of leukocyte rolling after ischemia-reperfusion injury or extracorporeal blood circulation. A similar effect was observed when we superfused leukotriene B4 (LTB4) onto the chamber tissue. The initial increase in leukocyte rolling in response to an LTB4 challenge was reversed by a second superfusion 90 min later. These observations underscore 1) the benefit of studying leukocyte-endothelial cell interaction in chronically instrumented chamber models and 2) the necessity to strictly adhere to well-established criteria of a physiological microcirculation.

Comparison of several maneuvering target tracking models

NASA Astrophysics Data System (ADS)

McIntyre, Gregory A.; Hintz, Kenneth J.

1998-07-01

The tracking of maneuvering targets is complicated by the fact that acceleration is not directly observable or measurable. Additionally, acceleration can be induced by a variety of sources including human input, autonomous guidance, or atmospheric disturbances. The approaches to tracking maneuvering targets can be divided into two categories both of which assume that the maneuver input command is unknown. One approach is to model the maneuver as a random process. The other approach assumes that the maneuver is not random and that it is either detected or estimated in real time. The random process models generally assume one of two statistical properties, either white noise or an autocorrelated noise. The multiple-model approach is generally used with the white noise model while a zero-mean, exponentially correlated acceleration approach is used with the autocorrelated noise model. The nonrandom approach uses maneuver detection to correct the state estimate or a variable dimension filter to augment the state estimate with an extra state component during a detected maneuver. Another issue with the tracking of maneuvering target is whether to perform the Kalman filter in Polar or Cartesian coordinates. This paper will examine and compare several exponentially correlated acceleration approaches in both Polar and Cartesian coordinates for accuracy and computational complexity. They include the Singer model in both Polar and Cartesian coordinates, the Singer model in Polar coordinates converted to Cartesian coordinates, Helferty's third order rational approximation of the Singer model and the Bar-Shalom and Fortmann model. This paper shows that these models all provide very accurate position estimates with only minor differences in velocity estimates and compares the computational complexity of the models.

Identification and quantification of human microcirculatory leukocytes using handheld video microscopes at the bedside.

PubMed

Uz, Zühre; van Gulik, Thomas M; Aydemirli, Mehtap Derya; Guerci, Philippe; Ince, Yasin; Cuppen, Diede V; Ergin, Bulent; Aksu, Ugur; de Mol, Bas A; Ince, Can

2018-03-08

Leukocyte recruitment and adhesion to the endothelium are hallmarks of systemic inflammation that manifest in a wide range of diseases. At present, no method is available to directly measure leukocyte kinetics at the bedside. In this study, we validate a new method to identify and quantify microcirculatory leukocytes observed by handheld vital microscopy (HVM) using space-time diagram (STD) analysis. Video clips (N=59) containing one capillary-post capillary venule (C-PCV) unit where leukocytes could be observed emanating from a capillary into a venule in cardiac surgery patients (N=20) were included. STD analysis and manual counting were used to quantify the number of leukocytes (total, rolling and non-rolling). Pearson's correlation and Bland-Altman analysis were used to determine agreement between the STDs and manual counting. For reproducibility, intra- and inter-observer coefficients of variation (CVs) were assessed. Leukocyte (rolling and non-rolling) and red blood cell velocities were assessed. The STDs and manual counting procedures for the quantification of rolling leukocytes showed good agreement (r=0.8197, P<0.0001), with a Bland-Altman analysis mean difference of -0.0 (-6.56; 6.56). The overall intra-observer CV for the STD method was 1.5%. The overall inter-observer CVs for the STD and the manual method were 5.6% and 9.4%, respectively. The non-rolling velocity was significantly higher than the rolling velocity (812{plus minus}519 µm/s vs 201{plus minus}149 µm/s, P=0.001). The STD results agreed with the manual counting procedure results, had a better reproducibility and could assess the leukocyte velocity. STD analysis using bedside HVM imaging presented a new methodology for quantifying leukocyte kinetics and functions in the microcirculation.

Cognitive-behavioral stress management reverses anxiety-related leukocyte transcriptional dynamics

PubMed Central

Antoni, Michael H.; Lutgendorf, Susan K.; Blomberg, Bonnie; Carver, Charles S.; Lechner, Suzanne; Diaz, Alain; Stagl, Jamie; Arevalo, Jesusa M.G.; Cole, Steven W.

2011-01-01

Background Chronic threat and anxiety are associated with pro-inflammatory transcriptional profiles in circulating leukocytes, but the causal direction of that relationship has not been established. This study tested whether a Cognitive-Behavioral Stress Management (CBSM) intervention targeting negative affect and cognition might counteract anxiety-related transcriptional alterations in people confronting a major medical threat. Methods 199 women undergoing primary treatment of Stage 0–III breast cancer were randomized to a 10-week CBSM protocol or an active control condition. 79 provided peripheral blood leukocyte samples for genome-wide transcriptional profiling and bioinformatic analyses at baseline, 6-, and 12-month follow-ups. Results Baseline negative affect was associated with > 50% differential expression of 201 leukocyte transcripts, including up-regulated expression of pro-inflammatory and metastasis-related genes. CBSM altered leukocyte expression of 91 genes by > 50% at follow-up (Group × Time interaction), including down-regulation of pro-inflammatory and metastasis-related genes and up-regulation of Type I interferon response genes. Promoter-based bioinformatic analyses implicated decreased activity of NF-κB/Rel and GATA family transcription factors and increased activity of Interferon Response Factors and the Glucocorticoid Receptor (GR) as potential mediators of CBSM-induced transcriptional alterations. Conclusions In early stage breast cancer patients, a 10-week CBSM intervention can reverse anxiety-related up-regulation of pro-inflammatory gene expression in circulating leukocytes. These findings clarify the molecular signaling pathways by which behavioral interventions can influence physical health and alter peripheral inflammatory processes that may reciprocally affect brain affective and cognitive processes. PMID:22088795

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…

Comprehensive evaluation of leukocyte lineage derived from human hematopoietic cells in humanized mice.

PubMed

Takahashi, Masayuki; Tsujimura, Noriyuki; Otsuka, Kensuke; Yoshino, Tomoko; Mori, Tetsushi; Matsunaga, Tadashi; Nakasono, Satoshi

2012-04-01

Recently, humanized animals whereby a part of the animal is biologically engineered using human genes or cells have been utilized to overcome interspecific differences. Herein, we analyzed the detail of the differentiation states of various human leukocyte subpopulations in humanized mouse and evaluated comprehensively the similarity of the leukocyte lineage between humanized mice and humans. Humanized mice were established by transplanting human CD34(+) cord blood cells into irradiated severely immunodeficient NOD/Shi-scid/IL2Rγ(null) (NOG) mice, and the phenotypes of human cells contained in bone marrow, thymus, spleen and peripheral blood from the mice were analyzed at monthly intervals until 4 months after cell transplantation. The analysis revealed that transplanted human hematopoietic stem cells via the caudal vein homed and engrafted themselves successfully at the mouse bone marrow. Subsequently, the differentiated leukocytes migrated to the various tissues. Almost all of the leukocytes within the thymus were human cells. Furthermore, analysis of the differentiation states of human leukocytes in various tissues and organs indicated that it is highly likely that the human-like leukocyte lineage can be developed in mice. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Systematic Errors in an Air Track Experiment.

ERIC Educational Resources Information Center

Ramirez, Santos A.; Ham, Joe S.

1990-01-01

Errors found in a common physics experiment to measure acceleration resulting from gravity using a linear air track are investigated. Glider position at release and initial velocity are shown to be sources of systematic error. (CW)

Flow cytometric analysis of leukocytes and reticulocytes stained with proflavine.

PubMed

Sagawa, H; Tatsumi, N

1997-12-01

Proflavine, an acridine analog for industrial use, was used to stain blood cells. A drop of blood treated with ethylenediaminetetraacetic acid-2K was mixed with a 0.00001% solution of the dye and observed immediately by fluorescence microscopy with a green filter. Leukocytes, platelets, and reticulocytes were stained but mature red blood cells were not. Chromatin in the nuclei of all leukocytes and nucleoli of lymphocytes and monocytes had greenish-yellow fluorescence, and the kind of cell could be identified by the tone and intensity of this color. Granules in granulocytes were in green. Reticular fine-granular or granulofibrous structures in the reticulocytes were brownish. The proflavine could be used routinely in clinical laboratories because this single stain makes possible simultaneous differentiation of leukocytes and counting of reticulocytes.

Slab track field test and demonstration program for shared freight and high-speed passenger service

DOT National Transportation Integrated Search

2010-08-01

Two types of slab tracks were installed on the High Tonnage Loop at the Facility for Accelerated Service Testing. Direct fixation slab track (DFST) and independent dual block track (IDBT) were installed into a 5-degree curve with 4-inch superelevatio...

Subacute Low Dose Nerve Agent Exposure Causes DNA Fragmentation in Guinea Pig Leukocytes

DTIC Science & Technology

2005-10-01

1 SUBACUTE LOW DOSE NERVE AGENT EXPOSURE CAUSES DNA FRAGMENTATION IN GUINEA PIG LEUKOCYTES. Jitendra R. Dave1, John R. Moffett1, Sally M...DNA fragmentation in blood leukocytes from guinea pigs by ‘Comet’ assay after exposure to soman at doses ranging from 0.1LD50 to 0.4 LD50, once per...computer. Data obtained for exposure to soman demonstrated significant increases in DNA fragmentation in circulating leukocytes in CWNA treated guinea pigs as

Evaluation of polyacrylonitrile electrospun nano-fibrous mats as leukocyte removal filter media.

PubMed

Pourbaghi, Raha; Zarrebini, Mohammad; Semnani, Dariush; Pourazar, Abbasali; Akbari, Nahid; Shamsfar, Reihaneh

2018-07-01

Removal of leukocytes from blood products is the most effective means for elimination of undesirable side effects and prevention of possible reactions in recipients. Micro-fibrous mats are currently used for removal of leukocytes from blood. In this study, samples of electrospun nano-fibrous mats were produced. The performance of the produced electrospun nano-fibrous mats as means of leukocytes removal from fresh whole blood was both evaluated and compared with that of commercially available micro-fibrous mats. In order to produce the samples, polyacrylonitrile (PAN) nano-fibrous mats were made under different electrospinning conditions. Mean fiber diameter, pore characterization and surface roughness of the PAN nano-fibrous mats were determined using image processing technique. In order to evaluate the surface tension of the fabricated mats, water contact angle was measured. The leukocyte removal performance, erythrocytes recovery percent and hemolysis rate of the nano-fibrous mats were compared. The effectiveness of nano-fibrous mats in removing leukocyte was established using both scanning electron microscope and optical microscope. Results showed that for given weight, the fabricated nano-fibrous mats were not only more efficient but also more cost-effective than their commercial counterparts. Results confirmed that changes in mean fiber diameter, the number of layer and weight of each layer in the absence of any chemical reaction or physical surface modification, the fabricated nano-fibrous mats were able to remove 5-log of leukocytes. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1759-1769, 2018. © 2017 Wiley Periodicals, Inc.

Synchronous acceleration with tapered dielectric-lined waveguides

NASA Astrophysics Data System (ADS)

Lemery, F.; Floettmann, K.; Piot, P.; Kärtner, F. X.; Aßmann, R.

2018-05-01

We present a general concept to accelerate nonrelativistic charged particles. Our concept employs an adiabatically-tapered dielectric-lined waveguide which supports accelerating phase velocities for synchronous acceleration. We propose an ansatz for the transient field equations, show it satisfies Maxwell's equations under an adiabatic approximation and find excellent agreement with a finite-difference time-domain computer simulation. The fields were implemented into the particle-tracking program astra and we present beam dynamics results for an accelerating field with a 1-mm-wavelength and peak electric field of 100 MV /m . Numerical simulations indicate that a ˜200 -keV electron beam can be accelerated to an energy of ˜10 MeV over ˜10 cm with parameters of interest to a wide range of applications including, e.g., future advanced accelerators, and ultra-fast electron diffraction.

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

Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight men.

PubMed

Esser, Diederik; Mars, Monica; Oosterink, Els; Stalmach, Angelique; Müller, Michael; Afman, Lydia A

2014-03-01

Flavanol-enriched chocolate consumption increases endothelium-dependent vasodilation. Most research so far has focused on flow-mediated dilation (FMD) only; the effects on other factors relevant to endothelial health, such as inflammation and leukocyte adhesion, have hardly been addressed. We investigated whether consumption of regular dark chocolate also affects other markers of endothelial health, and whether chocolate enrichment with flavanols has additional benefits. In a randomized double-blind crossover study, the effects of acute and of 4 wk daily consumption of high flavanol chocolate (HFC) and normal flavanol chocolate (NFC) on FMD, augmentation index (AIX), leukocyte count, plasma cytokines, and leukocyte cell surface molecules in overweight men (age 45-70 yr) were investigated. Sensory profiles and motivation scores to eat chocolate were also collected. Findings showed that a 4 wk chocolate intake increased FMD by 1%, which was paralleled by a decreased AIX of 1%, decreased leukocyte cell count, decreased plasma sICAM1 and sICAM3, and decreased leukocyte adhesion marker expression (P<0.05 for time effect), with no difference between HFC and NFC consumption. Flavanol enrichment did affect taste and negatively affected motivation to consume chocolate. This study provides new insights on how chocolate affects endothelial health by demonstrating that chocolate consumption, besides improving vascular function, also lowers the adherence capacity of leukocytes in the circulation.

Effects of conventional and new peritoneal dialysis fluids on leukocyte recruitment in the rat peritoneal membrane.

PubMed

Mortier, Siska; De Vriese, An S; McLoughlin, Rachel M; Topley, Nicholas; Schaub, Thomas P; Passlick-Deetjen, Jutta; Lameire, Norbert H

2003-05-01

Peritonitis remains an important cause of morbidity and technique failure in peritoneal dialysis (PD). Conventional peritoneal dialysate fluids (PDF) inhibit peritoneal leukocyte function in vitro and may thus adversely affect the immune response to peritonitis. New PDF have been designed with neutral pH, low glucose degradation product (GDP) contents, and bicarbonate as buffer. The present intravital microscopy study examined the effects of conventional and new PDF on leukocyte behavior in the peritoneal microcirculation of Wistar rats. The visceral peritoneum was superfused by a control solution (EBSS), a conventional (CAPD), or a new bicarbonate-buffered PDF with neutral pH and low GDP content (CAPD BicaVera). In addition, spent conventional and new PDF were tested. The number of rolling, adhering, and extravasated leukocytes and leukocyte rolling velocity were assessed at different time intervals after exposure to lipopolysaccharide (LPS) or cell-free supernatants of coagulase-negative staphylococci (CNS-CFS). Exposure to LPS or CNS-CFS dissolved in EBSS dramatically increased the number of rolling, adhering and extravasated leukocytes and decreased leukocyte rolling velocity. Superfusion by CAPD abolished the LPS- or CNS-CFS-induced leukocyte recruitment, whereas CAPD BicaVera had significantly fewer depressant effect. Spent PDF affected the leukocyte response in a similar way as fresh PDF. High lactate concentrations, GDP, and hypertonicity appeared to be mainly responsible for the inhibition of leukocyte recruitment. In conclusion, conventional PDF abolish in vivo leukocyte recruitment in response to potent inflammatory stimuli. Bicarbonate-buffered pH-neutral PDF with low GDP contents have fewer depressant effects and may therefore contribute to a better preservation of peritoneal host defense.

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

Measurement of leukocyte rheology in vascular disease: clinical rationale and methodology. International Society of Clinical Hemorheology.

PubMed

Wautier, J L; Schmid-Schönbein, G W; Nash, G B

1999-01-01

The measurement of leukocyte rheology in vascular disease is a recent development with a wide range of new opportunities. The International Society of Clinical Hemorheology has asked an expert panel to propose guidelines for the investigation of leukocyte rheology in clinical situations. This article first discusses the mechanical, adhesive and related functional properties of leukocytes (especially neutrophils) which influence their circulation, and establishes the rationale for clinically-related measurements of parameters which describe them. It is concluded that quantitation of leukocyte adhesion molecules, and of their endothelial receptors may assist understanding of leukocyte behaviour in vascular disease, along with measurements of flow resistance of leukocytes, free radical production, degranulation and gene expression. For instance, vascular cell adhesion molecule (VCAM-1) is abnormally present on endothelial cells in atherosclerosis, diabetes mellitus and inflammatory conditions. Soluble forms of intercellular adhesion molecule (ICAM-1) or VCAM can be found elevated in the blood of patients with rheumatoid arthritis or infections disease. In the second part of the article, possible technical approaches are presented and possible avenues for leukocyte rheological investigations are discussed.

Evaluation of ascitic soluble human leukocyte antigen-G for distinguishing malignant ascites from benign ascites.

PubMed

Sun, Juan; Chang, Yan-Xiang; Niu, Chun-Yan

2017-11-01

The overexpression of soluble human leukocyte antigen-G is associated with malignant tumours. The purpose of our study was to detect soluble human leukocyte antigen-G concentrations in ascites and to evaluate the value of ascitic soluble human leukocyte antigen-G for the diagnosis of malignant ascites. Enzyme-linked immunosorbent assay was used to detect soluble human leukocyte antigen-G levels in 64 patients with malignant ascites and 30 patients with benign ascites. Receiver operating characteristic curves were used to evaluate the diagnostic efficacy of ascitic soluble human leukocyte antigen-G for the detection of malignant ascites. Ascitic soluble human leukocyte antigen-G levels were significantly higher in the malignant ascites group than in the benign ascites group (20.718 ± 3.215 versus 12.467 ± 3.678 µg/L, t = 7.425, p < 0.001). The area under the receiver operating characteristic curve for ascitic soluble human leukocyte antigen-G was 0.957 (95% confidence interval, 0.872-0.992). At a cut-off value of 19.60 µg/L, the sensitivity and specificity of ascitic soluble human leukocyte antigen-G were 87.5% (95% confidence interval, 71.0%-96.5%) and 100% (95% confidence interval, 88.4%-100%), respectively. With respect to area under the receiver operating characteristic curve, sensitivity and specificity, ascitic carcinoembryonic antigen (0.810, 68.75% and 83.33%, respectively) and carbohydrate antigen 19-9 (0.710, 65.63% and 70%, respectively) significantly differed (all p < 0.05). In malignant ascites that were cytology-negative and biopsy-positive, the rate of positivity for ascitic soluble human leukocyte antigen-G was 75%, which was higher than the corresponding rates for ascitic carcinoembryonic antigen (31.25%) and carbohydrate antigen 19-9 (6.25%; both p < 0.05). In conclusion, The detection of ascitic soluble human leukocyte antigen-G exhibited good performance for diagnosing malignant ascites, and particularly those that

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparative Study of 6-Mercaptopurine Metabolism in Human Leukemic Leukocytes and L1210 Cells

PubMed Central

Higuchi, Tomihiko; Nakamura, Toru; Uchino, Haruto; Wakisaka, Gyoichi

1977-01-01

Leukocytes from patients with leukemia and L1210 cells from mice were examined for the rate of formation and cellular concentration of phosphoribosylpyrophosphate, the rate of thioinosinic acid formation, and a number of selected enzymes involved in purine nucleotide synthesis. The amount of thioinosinic acid formed in L1210 cells was much higher than that in human leukemic leukocytes. In cell extracts, the synthesis of thioinosinic acid was similar in both cell types, and the amount of purine phosphoribosyltransferase was not rate limiting in either case. Much higher concentrations and rates of formation of phosphoribosylpyrophosphate were found in L1210 cells than in human leukemic leukocytes. The difference in response to 6-mercaptopurine between L1210 cells and human leukemic leukocytes might be attributed to their difference in supply of phosphoribosylpyrophosphate. Phosphoribosylpyrophosphate-amidotransferase was found to be high in L1210 cells, but was not detected in human leukemic leukocytes. PMID:921247

Adjusting MtDNA Quantification in Whole Blood for Peripheral Blood Platelet and Leukocyte Counts.

PubMed

Hurtado-Roca, Yamilee; Ledesma, Marta; Gonzalez-Lazaro, Monica; Moreno-Loshuertos, Raquel; Fernandez-Silva, Patricio; Enriquez, Jose Antonio; Laclaustra, Martin

2016-01-01

Alterations of mitochondrial DNA copy number (mtDNAcn) in the blood (mitochondrial to nuclear DNA ratio) appear associated with several systemic diseases, including primary mitochondrial disorders, carcinogenesis, and hematologic diseases. Measuring mtDNAcn in DNA extracted from whole blood (WB) instead of from peripheral blood mononuclear cells or buffy coat may yield different results due to mitochondrial DNA present in platelets. The aim of this work is to quantify the contribution of platelets to mtDNAcn in whole blood [mtDNAcn(WB)] and to propose a correction formula to estimate leukocytes' mtDNAcn [mtDNAcn(L)] from mtDNAcn(WB). Blood samples from 10 healthy adults were combined with platelet-enriched plasma and saline solution to produce artificial blood preparations. Aliquots of each sample were combined with five different platelet concentrations. In 46 of these blood preparations, mtDNAcn was measured by qPCR. MtDNAcn(WB) increased 1.07 (95%CI 0.86, 1.29; p<0.001) per 1000 platelets present in the preparation. We proved that leukocyte count should also be taken into account as mtDNAcn(WB) was inversely associated with leukocyte count; it increased 1.10 (95%CI 0.95, 1.25, p<0.001) per unit increase of the ratio between platelet and leukocyte counts. If hematological measurements are available, subtracting 1.10 the platelets/leukocyte ratio from mtDNAcn(WB) may serve as an estimation for mtDNAcn(L). Both platelet and leukocyte counts in the sample are important sources of variation if comparing mtDNAcn among groups of patients when mtDNAcn is measured in DNA extracted from whole blood. Not taking the platelet/leukocyte ratio into account in whole blood measurements, may lead to overestimation and misclassification if interpreted as leukocytes' mtDNAcn.

Transformation of ATLA-negative leukocytes by blood components from anti-ATLA-positive donors in vitro.

PubMed

Miyamoto, K; Tomita, N; Ishii, A; Nishizaki, T; Kitajima, K; Tanaka, T; Nakamura, T; Watanabe, S; Oda, T

1984-06-15

Anti-ATLA-positive blood components transformed healthy human leukocytes in vitro. Blood components examined were packed red cells, whole blood, platelet concentrate and fresh frozen plasma. Leukocytes present in anti-ATLA-positive blood components such as packed red cells, whole blood and platelet concentrate easily transformed anti-ATLA-negative leukocytes. Co-culture in fresh frozen plasma, however, did not transform recipient leukocytes, and leukocytes of anti-ATLA-positive recipients proved refractory to transformation. The transformed cells were morphologically lymphoid, grew in suspension, and possessed normal recipient karyotypes except in the case of three platelet concentrates. A high proportion of all the transformed populations formed E-rosettes with neuraminidase-treated sheep erythrocytes. The cytoplasm of over 90% of each recipient was stained brilliantly with antibodies against ATLV-determined antigens. Electron microscopy of these transformed cells revealed many C-type virus particles in the extracellular space. Blood components, such as packed red cells, whole blood and platelet concentrate, containing leukocytes from anti-ATLA-positive donors, should be used cautiously to prevent the transmission on ATLV to anti-ATLA-negative recipients.

Accelerated magnetic resonance diffusion tensor imaging of the median nerve using simultaneous multi-slice echo planar imaging with blipped CAIPIRINHA.

PubMed

Filli, Lukas; Piccirelli, Marco; Kenkel, David; Boss, Andreas; Manoliu, Andrei; Andreisek, Gustav; Bhat, Himanshu; Runge, Val M; Guggenberger, Roman

2016-06-01

To investigate the feasibility of MR diffusion tensor imaging (DTI) of the median nerve using simultaneous multi-slice echo planar imaging (EPI) with blipped CAIPIRINHA. After federal ethics board approval, MR imaging of the median nerves of eight healthy volunteers (mean age, 29.4 years; range, 25-32) was performed at 3 T using a 16-channel hand/wrist coil. An EPI sequence (b-value, 1,000 s/mm(2); 20 gradient directions) was acquired without acceleration as well as with twofold and threefold slice acceleration. Fractional anisotropy (FA), mean diffusivity (MD) and quality of nerve tractography (number of tracks, average track length, track homogeneity, anatomical accuracy) were compared between the acquisitions using multivariate ANOVA and the Kruskal-Wallis test. Acquisition time was 6:08 min for standard DTI, 3:38 min for twofold and 2:31 min for threefold acceleration. No differences were found regarding FA (standard DTI: 0.620 ± 0.058; twofold acceleration: 0.642 ± 0.058; threefold acceleration: 0.644 ± 0.061; p ≥ 0.217) and MD (standard DTI: 1.076 ± 0.080 mm(2)/s; twofold acceleration: 1.016 ± 0.123 mm(2)/s; threefold acceleration: 0.979 ± 0.153 mm(2)/s; p ≥ 0.074). Twofold acceleration yielded similar tractography quality compared to standard DTI (p > 0.05). With threefold acceleration, however, average track length and track homogeneity decreased (p = 0.004-0.021). Accelerated DTI of the median nerve is feasible. Twofold acceleration yields similar results to standard DTI. • Standard DTI of the median nerve is limited by its long acquisition time. • Simultaneous multi-slice acquisition is a new technique for accelerated DTI. • Accelerated DTI of the median nerve yields similar results to standard DTI.

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. Copyright © 2016 Elsevier

Fast track in hip arthroplasty

PubMed Central

Hansen, Torben Bæk

2017-01-01

‘Fast-track’ surgery was introduced more than 20 years ago and may be defined as a co-ordinated peri-operative approach aimed at reducing surgical stress and facilitating post-operative recovery.The fast-track programmes have now been introduced into total hip arthroplasty (THA) surgery with reduction in post-operative length of stay, shorter convalescence and rapid functional recovery without increased morbidity and mortality. This has been achieved by focusing on a multidisciplinary collaboration and establishing ‘fast-track’ units, with a well-defined organisational set-up tailored to deliver an accelerated peri-operative course of fast-track surgical THA procedures.Fast-track THA surgery now works extremely well in the standard THA patient. However, all patients are different and fine-tuning of the multiple areas in fast-track pathways to get patients with special needs or high co-morbidity burden through a safe and effective fast-track THA pathway is important.In this narrative review, the principles of fast-track THA surgery are presented together with the present status of implementation and perspectives for further improvements. Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160060. Originally published online at www.efortopenreviews.org PMID:28630756

Uropod elongation is a common final step in leukocyte extravasation through inflamed vessels

PubMed Central

Hyun, Young-Min; Sumagin, Ronen; Sarangi, Pranita P.; Lomakina, Elena; Overstreet, Michael G.; Baker, Christina M.; Fowell, Deborah J.; Waugh, Richard E.; Sarelius, Ingrid H.

2012-01-01

The efficient trafficking of immune cells into peripheral nonlymphoid tissues is key to enact their protective functions. Despite considerable advances in our understanding of cell migration in secondary lymphoid organs, real-time leukocyte recruitment into inflamed tissues is not well characterized. The conventional multistep paradigm of leukocyte extravasation depends on CD18 integrin–mediated events such as rapid arrest and crawling on the surface of the endothelium and transmigration through the endothelial layer. Using enhanced three-dimensional detection of fluorescent CD18 fusion proteins in a newly developed knockin mouse, we report that extravasating leukocytes (neutrophils, monocytes, and T cells) show delayed uropod detachment and become extremely elongated before complete transmigration across the endothelium. Additionally, these cells deposit CD18+ microparticles at the subendothelial layer before retracting the stretched uropod. Experiments with knockout mice and blocking antibodies reveal that the uropod elongation and microparticle formation are the result of LFA-1–mediated adhesion and VLA-3–mediated cell migration through the vascular basement membrane. These findings suggest that uropod elongation is a final step in the leukocyte extravasation cascade, which may be important for precise regulation of leukocyte recruitment into inflamed tissues. PMID:22711877

Direct Laser Acceleration in Laser Wakefield Accelerators

NASA Astrophysics Data System (ADS)

Shaw, J. L.; Froula, D. H.; Marsh, K. A.; Joshi, C.; Lemos, N.

2017-10-01

The direct laser acceleration (DLA) of electrons in a laser wakefield accelerator (LWFA) has been investigated. We show that when there is a significant overlap between the drive laser and the trapped electrons in a LWFA cavity, the accelerating electrons can gain energy from the DLA mechanism in addition to LWFA. The properties of the electron beams produced in a LWFA, where the electrons are injected by ionization injection, have been investigated using particle-in-cell (PIC) code simulations. Particle tracking was used to demonstrate the presence of DLA in LWFA. Further PIC simulations comparing LWFA with and without DLA show that the presence of DLA can lead to electron beams that have maximum energies that exceed the estimates given by the theory for the ideal blowout regime. The magnitude of the contribution of DLA to the energy gained by the electron was found to be on the order of the LWFA contribution. The presence of DLA in a LWFA can also lead to enhanced betatron oscillation amplitudes and increased divergence in the direction of the laser polarization. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

Higher leukocyte count predicts 3-month poor outcome of ruptured cerebral aneurysms.

PubMed

Yao, Pei-Sen; Chen, Guo-Rong; Xie, Xue-Ling; Shang-Guan, Huang-Cheng; Gao, Jin-Zhen; Lin, Yuan-Xiang; Zheng, Shu-Fa; Lin, Zhang-Ya; Kang, De-Zhi

2018-04-11

It is not fully established whether leukocyte can predict the poor outcome for ruptured cerebral aneurysms (CA) or not. Here, we retrospectively analyzed the clinical data of 428 patients with ruptured CA between 2010 and 2015. Patients' demographic data, including gender, age, history of smoking, alcohol, hypertension, diabetes and hypercholesterolemia, Hunt-Hess and Fisher grade, occurrence of hydrocephalus, aneurysm location, time to surgery, delayed ischemic neurological deficit (DIND) and peak leukocyte of blood test from day 1 to 3 after aneurysmal rupture were recorded and analyzed. In the multivariable analysis model, gender, Fisher grade, time to surgery and hydrocephalus were not relevant to poor outcome. However, Hunt-Hess grade, DIND and preoperative leukocyte count (>13.84 × 10 9 /L) were significantly associated with adverse outcome. The respective increased risks were 5.2- (OR5.24, 95% CI 1.67-16.50, p = 0.005), 6.2-(OR 6.24, 95% CI 3.55-10.99, p < 0.001) and 10.9-fold (OR 9.35, 95% CI 5.98-19.97, p < 0.001). The study revealed that Hunt-Hess grade, DIND and preoperative leukocyte count (>13.84 × 10 9 /L) were independent risk factors for poor outcome of ruptured CA at 3 months. Higher leukocyte count is a convenient and useful marker to predict 3-month poor outcome for ruptured CA.

Effects of non-leukocyte-reduced and leukocyte-reduced packed red blood cell transfusions on oxygenation of rat spinotrapezius muscle

PubMed Central

Sundararajan, Sripriya; Dodhy, Sami C.; Pittman, Roland N.; Lewis, Stephen J.

2015-01-01

Leukoreduction of blood used for transfusion alleviates febrile transfusion reactions, graft versus host disease and alloimmunization to leukocyte antigen. However, the actual clinical benefit of leukoreduction in terms of microcirculatory tissue O2 delivery after packed red blood cell (pRBC) transfusion has not been investigated. As such, the aim of this study was to determine the effects of non-leukoreduced (NLR) and leukoreduced (LR) fresh pRBC transfusion on interstitial oxygenation in anesthetized male Sprague-Dawley rats. Interstitial fluid PO2 and arteriolar diameters in spinotrapezius muscle preparations were monitored before and after transfusion with NLR- or LR-pRBCs. The major findings were that (1) transfusion of NLR-pRBCs significantly decreased interstitial oxygenation whereas transfusion of LR-pRBCs did not, and (2) transfusion with LR-pRBCs elicited a substantially greater increase in arterial blood pressure (ABP) than did transfusion with NLR-pRBCs. These changes in PO2 and ABP were not associated with changes in the diameters of resistance arterioles in the spinotrapezius muscle. These data suggest that transfusion of fresh NLR-pRBCs may negatively affect tissue oxygenation via enhanced leukocyte influx and decreased O2 delivery. They also suggest that leukocytes diminish the capability of transfused pRBCs to increase cardiac output. As such, transfusion of LR-pRBCs may be less deleterious on tissue PO2 levels than NLR-pRBCs although a concomitantly greater increase in ABP may accompany transfusion of LR-pRBCs. PMID:24189119

TNFα promotes CAR-dependent migration of leukocytes across epithelial monolayers

PubMed Central

Morton, Penny E.; Hicks, Alexander; Ortiz-Zapater, Elena; Raghavan, Swetavalli; Pike, Rosemary; Noble, Alistair; Woodfin, Abigail; Jenkins, Gisli; Rayner, Emma; Santis, George; Parsons, Maddy

2016-01-01

Trans-epithelial migration (TEpM) of leukocytes during inflammation requires engagement with receptors expressed on the basolateral surface of the epithelium. One such receptor is Coxsackie and Adenovirus Receptor (CAR) that binds to Junctional Adhesion Molecule-like (JAM-L) expressed on leukocytes. Here we provide the first evidence that efficient TEpM of monocyte-derived THP-1 cells requires and is controlled by phosphorylation of CAR. We show that TNFα acts in a paracrine manner on epithelial cells via a TNFR1-PI3K-PKCδ pathway leading to CAR phosphorylation and subsequent transmigration across cell junctions. Moreover, we show that CAR is hyper-phosphorylated in vivo in acute and chronic lung inflammation models and this response is required to facilitate immune cell recruitment. This represents a novel mechanism of feedback between leukocytes and epithelial cells during TEpM and may be important in controlling responses to pro-inflammatory cytokines in pathological settings. PMID:27193388

Star tracking method based on multiexposure imaging for intensified star trackers.

PubMed

Yu, Wenbo; Jiang, Jie; Zhang, Guangjun

2017-07-20

The requirements for the dynamic performance of star trackers are rapidly increasing with the development of space exploration technologies. However, insufficient knowledge of the angular acceleration has largely decreased the performance of the existing star tracking methods, and star trackers may even fail to track under highly dynamic conditions. This study proposes a star tracking method based on multiexposure imaging for intensified star trackers. The accurate estimation model of the complete motion parameters, including the angular velocity and angular acceleration, is established according to the working characteristic of multiexposure imaging. The estimation of the complete motion parameters is utilized to generate the predictive star image accurately. Therefore, the correct matching and tracking between stars in the real and predictive star images can be reliably accomplished under highly dynamic conditions. Simulations with specific dynamic conditions are conducted to verify the feasibility and effectiveness of the proposed method. Experiments with real starry night sky observation are also conducted for further verification. Simulations and experiments demonstrate that the proposed method is effective and shows excellent performance under highly dynamic conditions.

Independent Confirmation of the Pioneer 10 Anomalous Acceleration

NASA Technical Reports Server (NTRS)

Markwardt, Craig B.

2002-01-01

I perform an independent analysis of radio Doppler tracking data from the Pioneer 10 spacecraft for the time period 1987-1994. All of the tracking data were taken from public archive sources, and the analysis tools were developed independently by myself. I confirm that an apparent anomalous acceleration is acting on the Pioneer 10 spacecraft, which is not accounted for by present physical models of spacecraft navigation. My best fit value for the acceleration, including corrections for systematic biases and uncertainties, is (8.60 plus or minus 1.34) x 10(exp -8) centimeters per second, directed towards the Sun. This value compares favorably to previous results. I examine the robustness of my result to various perturbations of the analysis method, and find agreement to within plus or minus 5%. The anomalous acceleration is reasonably constant with time, with a characteristic variation time scale of greater than 70 yr. Such a variation timescale is still too short to rule out on-board thermal radiation effects, based on this particular Pioneer 10 data set.

Incident angle dependence of proton response of CR-39 (TS-16) track detector

NASA Technical Reports Server (NTRS)

Oda, K.; Csige, I.; Yamauchi, T.; Miyake, H.; Benton, E. V.

1993-01-01

The proton response of the TS-16 type of CR-39 plastic nuclear track detector has been studied with accelerated and fast neutron induced protons in vacuum and in air. The diameters of etched tracks were measured as a function of etching time and the etch rate ratio and the etch induction layer were determined from the growth curve of the diameter using a variable etch rate ratio model. In the case of the accelerated protons in vacuum an anomalous incident angle dependence of the response is observed.

High efficiency RF amplifier development over wide dynamic range for accelerator application

NASA Astrophysics Data System (ADS)

Mishra, Jitendra Kumar; Ramarao, B. V.; Pande, Manjiri M.; Joshi, Gopal; Sharma, Archana; Singh, Pitamber

2017-10-01

Superconducting (SC) cavities in an accelerating section are designed to have the same geometrical velocity factor (βg). For these cavities, Radio Frequency (RF) power needed to accelerate charged particles varies with the particle velocity factor (β). RF power requirement from one cavity to other can vary by 2-5 dB within the accelerating section depending on the energy gain in the cavity and beam current. In this paper, we have presented an idea to improve operating efficiency of the SC RF accelerators using envelope tracking technique. A study on envelope tracking technique without feedback is carried out on a 1 kW, 325 MHz, class B (conduction angle of 180 degrees) tuned load power amplifier (PA). We have derived expressions for the efficiency and power output for tuned load amplifier operating on the envelope tracking technique. From the derived expressions, it is observed that under constant load resistance to the device (MOSFET), optimum amplifier efficiency is invariant whereas output power varies with the square of drain bias voltage. Experimental results on 1 kW PA module show that its optimum efficiency is always greater than 62% with variation less than 5% from mean value over 7 dB dynamic range. Low power amplifier modules are the basic building block for the high power amplifiers. Therefore, results for 1 kW PA modules remain valid for the high power solid state amplifiers built using these PA modules. The SC RF accelerators using these constant efficiency power amplifiers can improve overall accelerator efficiency.

Position and Acceleration for Airborne Gravity; the Impact of IMU Data

NASA Astrophysics Data System (ADS)

Preaux, S. A.; Diehl, T. M.; Holmes, S. A.; Weil, C.

2012-12-01

Accurate measurements in airborne gravimetry require high quality position and acceleration information in order to remove the effects of aircraft motion from the gravimeter signal. This study examines the impact of including Inertial Measurement Unit (IMU) data in position and acceleration determination for high altitude gravimetry as part of NGS's GRAV-D project. Processing with the IMU data provides a higher rate position solution that includes aircraft attitude information. The IMU can also be a source for velocity and acceleration information but these must be used with care as they contain the aircraft motion and the gravity signal. Results from the GRAV-D project's 2008 survey season in Alaska are used as a test case for this study. The use of a tightly coupled IMU+GPS solution reduced the survey RMS and standard deviation with respect to EGM08 by an average of 0.23 mGal per data track and improved the correlation between the data tracks and EGM08 by 0.04%. While these improvements appear small they represent approximately 10% of the discrepancy. Turbulent tracks showed the biggest improvement with localized improvements larger than 5 mGal in some cases. The measured gravity processed with either a GPS only position solution or a tightly coupled GPS+IMU position solution compared with EGM08 for one data track from the GRAV-D AK08 survey.

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.

Leukocyte Rolling on P-Selectin: A Three-Dimensional Numerical Study of the Effect of Cytoplasmic Viscosity

PubMed Central

Khismatullin, Damir B.; Truskey, George A.

2012-01-01

Rolling leukocytes deform and show a large area of contact with endothelium under physiological flow conditions. We studied the effect of cytoplasmic viscosity on leukocyte rolling using our three-dimensional numerical algorithm that treats leukocyte as a compound droplet in which the core phase (nucleus) and the shell phase (cytoplasm) are viscoelastic fluids. The algorithm includes the mechanical properties of the cell cortex by cortical tension and considers leukocyte microvilli that deform viscoelastically and form viscous tethers at supercritical force. Stochastic binding kinetics describes binding of adhesion molecules. The leukocyte cytoplasmic viscosity plays a critical role in leukocyte rolling on an adhesive substrate. High-viscosity cells are characterized by high mean rolling velocities, increased temporal fluctuations in the instantaneous velocity, and a high probability for detachment from the substrate. A decrease in the rolling velocity, drag, and torque with the formation of a large, flat contact area in low-viscosity cells leads to a dramatic decrease in the bond force and stable rolling. Using values of viscosity consistent with step aspiration studies of human neutrophils (5–30 Pa·s), our computational model predicts the velocities and shape changes of rolling leukocytes as observed in vitro and in vivo. PMID:22768931

Synchronous acceleration with tapered dielectric-lined waveguides

DOE PAGES

Lemery, Francois; Floettmann, Klaus; Piot, Philippe; ...

2018-05-25

Here, we present a general concept to accelerate non-relativistic charged particles. Our concept employs an adiabatically-tapered dielectric-lined waveguide which supports accelerating phase velocities for synchronous acceleration. We propose an ansatz for the transient field equations, show it satisfies Maxwell's equations under an adiabatic approximation and find excellent agreement with a finite-difference time-domain computer simulation. The fields were implemented into the particle-tracking program {\\sc astra} and we present beam dynamics results for an accelerating field with a 1-mm-wavelength and peak electric field of 100~MV/m. The numerical simulations indicate that amore » $$\\sim 200$$-keV electron beam can be accelerated to an energy of $$\\sim10$$~MeV over $$\\sim 10$$~cm. The novel scheme is also found to form electron beams with parameters of interest to a wide range of applications including, e.g., future advanced accelerators, and ultra-fast electron diffraction.« less

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.

Red blood cell and leukocyte alloimmunization in patients awaiting kidney transplantation

PubMed Central

da Silva, Silvia Fernandes Ribeiro; Ferreira, Gláucia Maria; da Silva, Sonia Leite; Alves, Tânia Maria de Oliveira; Ribeiro, Ilana Farias; Ribeiro, Thyciana Rodrigues; Cavalcante, Maria do Carmo Serpa

2013-01-01

Objective To determine the rates of red blood cell and leukocyte alloimmunization in patients with chronic kidney disease awaiting kidney transplantation. Methods In this cross-sectional and prospective study, the serum of 393 chronic kidney disease patients on a transplant waiting list in Ceará, Northeastern Brazil were tested for red cell and leukocyte antibodies. In addition, demographic, clinical and laboratory data were collected. Results The average age in the sample of 393 patients was 34.1 ± 14 years. Slightly more than half (208; 52.9%) were male. The average numbers of transfusions and gestations were 3.1 ± 3.3 and 1.6 ± 6, respectively. One third (33.6%) were alloimmunized: 78% with leukocyte antibodies, 9.1% with red cell antibodies and 12.9% with both. Red cell antibodies were detected in 29 cases (7.4%), 17 of whom were women, who had received more transfusions than the males (p-value < 0.0001). The most frequently detected red cell antibodies belonged to the Rh (24.1%) and Kell (13.8%) blood group systems. Leukocyte antibodies were detected in 30.5% of cases, 83 of whom were women, who had received more transfusions than the males (p-value < 0.0001) and were more reactive to panel reactive antibodies (p-value < 0.0001). The mean alloreactivity to panel reactive antibodies was 47.7 ± 31.2%. Conclusion Chronic kidney disease patients on the transplant waiting list in Ceará, Brazil, display high rates of red cell (7.4%) and leukocyte (30.5%) alloimmunization. In this sample, alloimmunization was significantly associated with the number of transfusions and gender. PMID:23904808

On the consistency among different approaches for nuclear track scanning and data processing

NASA Astrophysics Data System (ADS)

Inozemtsev, K. O.; Kushin, V. V.; Kodaira, S.; Shurshakov, V. A.

2018-04-01

The article describes various approaches for space radiation track measurement using CR-39™ detector (Tastrak). The results of comparing different methods for track scanning and data processing are presented. Basic algorithms for determination of track parameters are described. Every approach involves individual set of measured track parameters. For two sets, track scanning is sufficient in the plane of detector surface (2-D measurement), third set requires scanning in the additional projection (3-D measurement). An experimental comparison of considered techniques was made with the use of accelerated heavy ions Ar, Fe and Kr.

Enumeration of major peripheral blood leukocyte populations for multicenter clinical trials using a whole blood phenotyping assay.

PubMed

Hensley, Tiffany R; Easter, Austin B; Gerdts, Sarah E; De Rosa, Stephen C; Heit, Antje; McElrath, M Juliana; Andersen-Nissen, Erica

2012-09-16

Cryopreservation of peripheral blood leukocytes is widely used to preserve cells for immune response evaluations in clinical trials and offers many advantages for ease and standardization of immunological assessments, but detrimental effects of this process have been observed on some cell subsets, such as granulocytes, B cells, and dendritic cells. Assaying fresh leukocytes gives a more accurate picture of the in vivo state of the cells, but is often difficult to perform in the context of large clinical trials. Fresh cell assays are dependent upon volunteer commitments and timeframes and, if time-consuming, their application can be impractical due to the working hours required of laboratory personnel. In addition, when trials are conducted at multiple centers, laboratories with the resources and training necessary to perform the assays may not be located in sufficient proximity to clinical sites. To address these issues, we have developed an 11-color antibody staining panel that can be used with Trucount tubes (Becton Dickinson; San Jose, CA) to phenotype and enumerate the major leukocyte populations within the peripheral blood, yielding more robust cell-type specific information than assays such as a complete blood count (CBC) or assays with commercially-available panels designed for Trucount tubes that stain for only a few cell types. The staining procedure is simple, requires only 100 μl of fresh whole blood, and takes approximately 45 minutes, making it feasible for standard blood-processing labs to perform. It is adapted from the BD Trucount tube technical data sheet (version 8/2010). The staining antibody cocktail can be prepared in advance in bulk at a central assay laboratory and shipped to the site processing labs. Stained tubes can be fixed and frozen for shipment to the central assay laboratory for multicolor flow cytometry analysis. The data generated from this staining panel can be used to track changes in leukocyte concentrations over time in

Biological effectiveness of accelerated particles for the induction of chromosome damage: track structure effects.

PubMed

George, Kerry A; Hada, Megumi; Chappell, Lori; Cucinotta, Francis A

2013-07-01

We have investigated how radiation quality affects the induction of chromosomal aberrations in human cells. Human lymphocytes were irradiated in vitro with various energies of accelerated high charge and energy (HZE) particles including oxygen, neon, silicon, titanium and iron. Chromosome damage was assessed using three-color FISH chromosome painting in chemically induced premature chromosome condensation samples collected at first cell division after irradiation. The LET values for these particles ranged from 30 to 195 keV/μm, and their energies ranged from about 55 MeV/u to more than 1,000 MeV/u. The 89 and 142 MeV/u neon particles produced the most simple-type reciprocal exchanges per unit dose. For complex-type exchanges, 64 MeV/u neon and 450 MeV/u iron were equally effective and induced the greatest amount of complex damage. 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, and that a saturation cross section will be observed for different radiation qualities. Our results are consistent with model expectations within the limitation of experimental error, and provide the most extensive data that have been reported on the radiation quality dependences of chromosomal aberrations. © 2013 by Radiation Research Society

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

Longer leukocyte telomere length in Costa Rica's Nicoyan Peninsula: A population-based study

PubMed Central

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

2013-01-01

Studies in humans suggest that leukocyte telomere length may act as a marker of biological aging. We investigated whether individuals in the Nicoya region of Costa Rica, known for exceptional longevity, had longer telomere length than those in other parts of the country. After controlling for age, age squared, rurality, rainy season and gender, mean leukocyte telomere length in Nicoya was substantially longer (81 base pairs, p<0.05) than in other areas of Costa Rica, providing evidence of a biological pathway to which this notable longevity may be related. This relationship remains unchanged (79 base pairs, p<0.05) after statistically controlling for nineteen potential biological, dietary and social and demographic mediators. Thus the difference in mean leukocyte telomere length that characterizes this unique region does not appear to be explainable by traditional behavioral and biological risk factors. More detailed examination of mean leukocyte telomere length by age shows that the regional telomere length difference declines at older ages. PMID:23988653

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…

Chemotaxis of nurse shark leukocytes.

PubMed

Obenauf, S D; Smith, S H

1985-01-01

Studies were conducted to determine the ability of leukocytes from the nurse shark to migrate in an in vitro micropore filter chemotaxis assay and to determine optimal assay conditions and suitable attractants for such an assay. A migratory response was seen with several attractants: activated rat serum, activated shark plasma, and a pool of shark complement components. Only the response to activated rat serum was chemotactic, as determined by the checkerboard assay.

Experimental settlement and dynamic behavior of a portion of ballasted railway track under high speed trains

NASA Astrophysics Data System (ADS)

Al Shaer, A.; Duhamel, D.; Sab, K.; Foret, G.; Schmitt, L.

2008-09-01

The study of railway tracks under high speed trains is one of the most important researches in the domain of transport. A reduced scale experiment with three sleepers is presented to study the dynamic behavior and the settlement of ballasted tracks. A large number of trains passing at high speeds are simulated by signals, applied with the help of hydraulic jacks, having the shape of the letter M and representing the passages of bogies on sleepers. This experiment offers results such as displacements, accelerations, pressures and settlements that allow to better understand the dynamic behavior of a portion of a ballasted railway track at reduced scale and to estimate the settlement versus the number of load cycles. It was found that mechanical properties such as the global stiffness of the track can have important variations during the experiment. The settlement was also found to be a function of the acceleration of sleepers and above all it was observed, for accelerations above a critical value, that the increase of settlement per cycle was very high.

Proposal for an Accelerator R&D User Facility at Fermilab's Advanced Superconducting Test Accelerator (ASTA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Church, M.; Edwards, H.; Harms, E.

2013-10-01

Fermilab is the nation’s particle physics laboratory, supported by the DOE Office of High Energy Physics (OHEP). Fermilab is a world leader in accelerators, with a demonstrated track-record— spanning four decades—of excellence in accelerator science and technology. We describe the significant opportunity to complete, in a highly leveraged manner, a unique accelerator research facility that supports the broad strategic goals in accelerator science and technology within the OHEP. While the US accelerator-based HEP program is oriented toward the Intensity Frontier, which requires modern superconducting linear accelerators and advanced highintensity storage rings, there are no accelerator test facilities that support themore » accelerator science of the Intensity Frontier. Further, nearly all proposed future accelerators for Discovery Science will rely on superconducting radiofrequency (SRF) acceleration, yet there are no dedicated test facilities to study SRF capabilities for beam acceleration and manipulation in prototypic conditions. Finally, there are a wide range of experiments and research programs beyond particle physics that require the unique beam parameters that will only be available at Fermilab’s Advanced Superconducting Test Accelerator (ASTA). To address these needs we submit this proposal for an Accelerator R&D User Facility at ASTA. The ASTA program is based on the capability provided by an SRF linac (which provides electron beams from 50 MeV to nearly 1 GeV) and a small storage ring (with the ability to store either electrons or protons) to enable a broad range of beam-based experiments to study fundamental limitations to beam intensity and to develop transformative approaches to particle-beam generation, acceleration and manipulation which cannot be done elsewhere. It will also establish a unique resource for R&D towards Energy Frontier facilities and a test-bed for SRF accelerators and high brightness beam applications in support of the

Detection of occult abscesses with /sup 111/In-labeled leukocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, W.R.; Gurevich, N.; Goris, M.L.

1979-07-01

Clinicians are frequently faced with the problem of a patient in whom they suspect an occult abscess. In such a situation, there may be no clinical signs to localize the site of the abscess and often extensive investigations do not provide additional useful information. This report illustrates the efficacy of autologous leukocytes labeled with /sup 111/In oxine in detecting the site and extent of occult abscesses in two patients. The technique of in vitro lebeling of leukocytes is simple and has been mastered by all of our nuclear medicine technologists.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 themore » main findings and list directions for further work.« less

Leukocyte and platelet changes following low-dose lipopolysaccharide administration in five dogs.

PubMed

Flatland, B; Fry, M M; LeBlanc, C J; Rohrbach, B W

2011-02-01

Effects of low-dose LPS (0.1 μg/kg i.v.) on leukocyte and platelet parameters measured using an Advia 120 hematology analyzer were investigated. Five dogs received a saline sham treatment prior to LPS, and blood was collected before and 3, 6, and 24 h post-treatment. LPS-treated dogs had mild neutrophil toxic change and increased neutrophil bands at 3 and 6 h. Compared to saline-treated controls, total leukocyte, neutrophil, and monocyte counts of LPS-treated dogs were significantly decreased at 3 h and increased at 24 h. Compared to baseline, total leukocyte counts of LPS-treated dogs were significantly decreased at 3 h and increased at 24 h. Mean platelet volume was significantly increased and mean platelet component concentration was decreased at 3 h compared to baseline. Platelet count was significantly decreased at 3 and 6 h; plateletcrit did not change significantly. High dosage is not required in order to detect LPS-mediated hematologic effects in dogs. Low-dose LPS administration causes significant changes in leukocyte and platelet indices in dogs without causing severe clinical signs or death. Copyright © 2010 Elsevier Ltd. All rights reserved.

Pregnant human peripheral leukocyte migration during several late pregnancy clinical conditions: a cross-sectional observational study.

PubMed

Takeda, Jun; Fang, Xin; Olson, David M

2017-01-10

Parturition at term and preterm is characterized by sterile inflammatory processes occurring in the absence of infection whereby peripheral leukocytes infiltrate gestational tissues in response to chemotactic signals. In response to a homing signal, recruited leukocytes undergo diapedesis and extravasate through capillaries, migrating into stromal tissue. There they interact with resident immune and stromal cells to produce a mixture of matrix metalloproteinases, prostaglandins and cytokines including interleukin-1β (IL-1β) and IL-6 that in turn transform the uterus from pregnancy to parturition. Since migration is an early parturitional event our purpose was to study the migration of maternal peripheral blood leukocytes in response to a standard chemotactic signal during several different conditions of late pregnancy. We used a cross-sectional observational study design. Subjects were (sTL) spontaneous normal labour delivered vaginally at term, (TNL) elective caesarean section at term without labour, (PTL) preterm in labour, (PTNL) preterm not in labour, (TPTL) threatened preterm labour, and (pPROM) preterm with premature rupture of membranes. Leukocytes (100,000) obtained by venipuncture and chemotactic factor isolated from term labour fetal membranes were placed in the upper and lower halves, respectively, of a Boyden chamber separated by a filter with 3μm pores. Migrated leukocytes were assessed by flow cytometry. The number of leukocytes that migrated in 90 min was the primary outcome measure. Increased numbers of leukocytes from peripheral blood of women in labour (TL or PTL) or soon to go into labour (PPROM) migrated towards a chemotactic signal than did leukocytes from women not in labour (TNL, PTNL, or TPTL) (p < 0.0001). All pPROM delivered within 7d; TPTL delivered >30d. Receiver operating characteristic curve parameters indicated the cut-off point for delivery within 7d to be 37,082 leukocytes with sensitivity 78.1%, specificity 88.9%, positive

Antibiotic-Enhanced Phagocytosis of ’Borrelia recurrentis’ by Blood Polymorphonuclear Leukocytes.

DTIC Science & Technology

1979-11-30

hours after Butler 7 institution of antibiotic treatment. Polymorphonuclear leukocytes are known to release endogenous pyrogen after phagocytosis of...other bacteria (6), and endogenous pyrogen may be one of the mediators of the rigor and temperature rise in the Jarisch-Herxheimer reaction (2). Release...the pathogenesis of fever. XII. The effect of phagocytosis on the release of endogenous pyrogen by polymorphonuclear leukocytes. J. Exp. Med. 119:715

Acceleration profile of an acrobatic act during training and shows using wearable technology.

PubMed

Barker, Leland; Burnstein, Bryan; Mercer, John

2018-05-24

The purpose of this study was to describe the mechanical characteristics of a trampoline circus act and its individual tracks performed in training and shows using a tri-axial accelerometer. A track is an artist's specific role within a choreographed act. Seven male acrobats performed their trampoline act during training and shows while wearing a triaxial accelerometer and reported ratings of perceived exertion (RPE) after each trial. Average acceleration (AVG), root mean square (RMS), root mean to the fourth (RM4), time spent in specific acceleration ranges and RPE were measured/recorded from training and show acts. Paired t-tests compared dependent variables between training and show. Acceleration AVG, RMS and RM4 were significantly higher (p < 0.05) in training than show. RPE was significantly higher (p < 0.05) in show than training. No significant differences existed in time spent in any of the acceleration ranges between training and show. GPS devices have been used to manage workloads in field sports but are inoperable in theatres. But, inertial measurements may be an effective alternative to describe mechanical demands in theatre or arena environments. Wearable technology may be useful to coaches to improve understanding of track demands to manage artist workloads.

Seasonal changes in cortisol sensitivity and glucocorticoid receptor affinity and number in leukocytes of coho salmon

USGS Publications Warehouse

Maule, Alec G.; Schreck, Carl B.; Sharpe, Cameron

1993-01-01

To determine if there were organ-specific changes in immune responses or immune-endocrine interaction, we monitored in vitro immune response, cortisol sensitivity and number and affinity of glucocorticoid receptors (GR) in leukocytes from freshwater-adapted juvenile coho salmon (Oncorhynchus kisutch) during the physiological changes that prepare them to enter the marine environment. During this period, absolute immune response declined, but splenic leukocytes generated more antibody-producing cells than did cells from anterior kidney. Splenic leukocytes were initially more sensitive to the suppressive effects of cortisol and had fewer GR than leukocytes from the anterior kidney. Leukocytes from the anterior kidney were initially insensitive to cortisol but developed sensitivity at about the same time as the dissociation constant and number of GR increased. In vitro incubation of anterior kidney leukocytes in cortisol altered GR variables when experiments were conducted during March through September but not during November through February. In some years, changes in GR or immune responses were correlated with plasma cortisol titers, but in other years there was no correlation. Thus, the exact relation between cortisol, GR and immune response in anadromous salmonids is unclear and other factors are involved.

Leukocyte counts in urine reflect the risk of concomitant sepsis in bacteriuric infants: a retrospective cohort study.

PubMed

Bonsu, Bema K; Harper, Marvin B

2007-06-13

When urine infections are missed in febrile young infants with normal urinalysis, clinicians may worry about the risk--hitherto unverified--of concomitant invasion of blood and cerebrospinal fluid by uropathogens. In this study, we determine the extent of this risk. In a retrospective cohort study of febrile 0-89 day old infants evaluated for sepsis in an urban academic pediatric emergency department (1993-1999), we estimated rates of bacteriuric sepsis (urinary tract infections complicated by sepsis) after stratifying infants by urine leukocyte counts higher, or lower than 10 cells/hpf. We compared the global accuracy of leukocytes in urine, leukocytes in peripheral blood, body temperature, and age for predicting bacteruric sepsis. The global accuracy of each test was estimated by calculating the area under its receiver operating characteristic curve (AUC). Chi-square and Fisher exact tests compared count data. Medians for data not normally distributed were compared by the Kruskal-Wallis test. Two thousand two hundred forty-nine young infants had a normal screening dipstick. None of these developed bacteremia or meningitis despite positive urine culture in 41 (1.8%). Of 1516 additional urine specimens sent for formal urinalysis, 1279 had 0-9 leukocytes/hpf. Urine pathogens were isolated less commonly (6% vs. 76%) and at lower concentrations in infants with few, compared to many urine leukocytes. Urine leukocytes (AUC: 0.94) were the most accurate predictors of bacteruric sepsis. Infants with urinary leukocytes < 10 cells/hpf were significantly less likely (0%; CI:0-0.3%) than those with higher leukocyte counts (5%; CI:2.6-8.7%) to have urinary tract infections complicated by bacteremia (N = 11) or bacterial meningitis (N = 1)--relative risk, 0 (CI:0-0.06) [RR, 0 (CI: 0-0.02), when including infants with negative dipstick]. Bands in peripheral blood had modest value for detecting bacteriuric sepsis (AUC: 0.78). Cases of sepsis without concomitant bacteriuria were

21 CFR 864.7675 - Leukocyte peroxidase test.

Code of Federal Regulations, 2011 CFR

2011-04-01

... cells of the lymphatic system and erythroid cells of the red blood cell series on the basis of their... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... of the leukemias. (b) Classification. Class I (general controls). This device is exempt from the...

21 CFR 864.7675 - Leukocyte peroxidase test.

Code of Federal Regulations, 2013 CFR

2013-04-01

... cells of the lymphatic system and erythroid cells of the red blood cell series on the basis of their... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... of the leukemias. (b) Classification. Class I (general controls). This device is exempt from the...

21 CFR 864.7675 - Leukocyte peroxidase test.

Code of Federal Regulations, 2012 CFR

2012-04-01

... cells of the lymphatic system and erythroid cells of the red blood cell series on the basis of their... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... of the leukemias. (b) Classification. Class I (general controls). This device is exempt from the...

21 CFR 864.7675 - Leukocyte peroxidase test.

Code of Federal Regulations, 2010 CFR

2010-04-01

... cells of the lymphatic system and erythroid cells of the red blood cell series on the basis of their... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... of the leukemias. (b) Classification. Class I (general controls). This device is exempt from the...

21 CFR 864.7675 - Leukocyte peroxidase test.

Code of Federal Regulations, 2014 CFR

2014-04-01

... cells of the lymphatic system and erythroid cells of the red blood cell series on the basis of their... peroxidase test. (a) Identification. A leukocyte peroxidase test is a device used to distinguish certain... of the leukemias. (b) Classification. Class I (general controls). This device is exempt from the...

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.)

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)

High plasma folate is negatively associated with leukocyte telomere length in Framingham Offspring cohort.

PubMed

Paul, Ligi; Jacques, Paul F; Aviv, Abraham; Vasan, Ramachandran S; D'Agostino, Ralph B; Levy, Daniel; Selhub, Jacob

2015-03-01

Shortening of telomeres, the protective structures at the ends of eukaryotic chromosomes, is associated with age-related pathologies. Telomere length is influenced by DNA integrity and DNA and histone methylation. Folate plays a role in providing precursors for nucleotides and methyl groups for methylation reactions and has the potential to influence telomere length. We determined the association between leukocyte telomere length and long-term plasma folate status (mean of 4 years) in Framingham Offspring Study (n = 1,044, females = 52.1 %, mean age 59 years) using data from samples collected before and after folic acid fortification. Leukocyte telomere length was determined by Southern analysis and fasting plasma folate concentration using microbiological assay. There was no significant positive association between long-term plasma folate and leukocyte telomere length among the Framingham Offspring Study participants perhaps due to their adequate folate status. While the leukocyte telomere length in the second quintile of plasma folate was longer than that in the first quintile, the difference was not statistically significant. The leukocyte telomere length of the individuals in the fifth quintile of plasma folate was shorter than that of those in the second quintile by 180 bp (P < 0.01). There was a linear decrease in leukocyte telomere length with higher plasma folate concentrations in the upper four quintiles of plasma folate (P for trend = 0.001). Multivitamin use was associated with shorter telomeres in this cohort (P = 0.015). High plasma folate status possibly resulting from high folic acid intake may interfere with the role of folate in maintaining telomere integrity.

Slab Track at Facility for Accelerated Service Testing: Performance and Serviceability

DOT National Transportation Integrated Search

2018-02-01

The Transportation Technology Center, Inc., with funding by the Portland Cement Association and the Federal Railroad Administration, documented the available records associated with the performance of the concrete slab track section in the High Tonna...

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.

Experimental signatures of direct-laser-acceleration-assisted laser wakefield acceleration

NASA Astrophysics Data System (ADS)

Shaw, J. L.; Lemos, N.; Marsh, K. A.; Froula, D. H.; Joshi, C.

2018-04-01

The direct laser acceleration (DLA) of electrons in a laser wakefield accelerator (LWFA) operating in the forced or quasi-blowout regimes has been investigated through experiment and simulation. When there is a significant overlap between the trapped electrons and the drive laser in a LWFA cavity, the resulting electrons can gain energy from both the LWFA and the DLA mechanisms. Experimental work investigates the properties of the electron beams produced in a LWFA with ionization injection by dispersing those beams in the direction perpendicular to the laser polarization. These electron beams show certain spectral features that are characteristic of DLA. These characteristic features are reproduced using particle-in-cell simulations, where particle tracking was used to elucidate the roles of LWFA and DLA to the energy gain of the electrons in this experimental regime and to demonstrate that such spectral features are definitive signatures of the presence of DLA in LWFA.

Myeloid differentiation architecture of leukocyte transcriptome dynamics in perceived social isolation

PubMed Central

Cole, Steven W.; Capitanio, John P.; Chun, Katie; Arevalo, Jesusa M. G.; Ma, Jeffrey; Cacioppo, John T.

2015-01-01

To define the cellular mechanisms of up-regulated inflammatory gene expression and down-regulated antiviral response in people experiencing perceived social isolation (loneliness), we conducted integrative analyses of leukocyte gene regulation in humans and rhesus macaques. Five longitudinal leukocyte transcriptome surveys in 141 older adults showed up-regulation of the sympathetic nervous system (SNS), monocyte population expansion, and up-regulation of the leukocyte conserved transcriptional response to adversity (CTRA). Mechanistic analyses in a macaque model of perceived social isolation confirmed CTRA activation and identified selective up-regulation of the CD14++/CD16− classical monocyte transcriptome, functional glucocorticoid desensitization, down-regulation of Type I and II interferons, and impaired response to infection by simian immunodeficiency virus (SIV). These analyses identify neuroendocrine-related alterations in myeloid cell population dynamics as a key mediator of CTRA transcriptome skewing, which may both propagate perceived social isolation and contribute to its associated health risks. PMID:26598672

Flow cytofluorometric assay of human whole blood leukocyte DNA degradation in response to Yersinia pestis and Staphylococcus aureus

NASA Astrophysics Data System (ADS)

Kravtsov, Alexander L.; Grebenyukova, Tatyana P.; Bobyleva, Elena V.; Golovko, Elena M.; Malyukova, Tatyana A.; Lyapin, Mikhail N.; Kostyukova, Tatyana A.; Yezhov, Igor N.; Kuznetsov, Oleg S.

2001-05-01

Human leukocytes containing less than 2C DNA per cell (damaged or dead cells) were detected and quantified by flow cytometry and DNA-specific staining with ethidium bromide and mithramycin in whole blood infected with Staphylococcus aureus or Yersinia pestis. Addition of live S. aureus to the blood (100 microbe cells per one leukocyte) resulted in rapid degradation of leukocyte DNA within 3 to 6 hours of incubation at 37 degree(s)C. However, only about 50 percent cells were damaged and the leukocytes with the intact genetic apparatus could be found in the blood for a period up to 24 hours. The leukocyte injury was preceded by an increase of DNA per cell content (as compared to the normal one) that was likely to be connected with the active phagocytosis of S. aureus by granulocytes (2C DNA of diploid phagocytes plus the all bacterial DNA absorbed). In response to the same dose of actively growing (at 37 degree(s)C) virulent Y. pestis cells, no increase in DNA content per cell could be observed in the human blood leukocytes. The process of the leukocyte DNA degradation started after a 6-hour incubation, and between 18 to 24 hours of incubation about 90 percent leukocytes (phagocytes and lymphocytes) lost their specific DNA fluorescence. These results demonstrated a high potential of flow cytometry in comparative analysis in vitro of the leukocyte DNA degradation process in human blood in response to bacteria with various pathogenic properties. They agree with the modern idea of an apoptotic mechanism of immunosuppression in plague.

Morphogen and proinflammatory cytokine release kinetics from PRGF-Endoret fibrin scaffolds: evaluation of the effect of leukocyte inclusion.

PubMed

Anitua, E; Zalduendo, M M; Prado, R; Alkhraisat, M H; Orive, G

2015-03-01

The potential influence of leukocyte incorporation in the kinetic release of growth factors from platelet-rich plasma (PRP) may explain the conflicting efficiency of leukocyte platelet-rich plasma (L-PRP) scaffolds in tissue regeneration. To assess this hypothesis, leukocyte-free (PRGF-Endoret) and L-PRP fibrin scaffolds were prepared, and both morphogen and proinflammatory cytokine release kinetics were analyzed. Clots were incubated with culture medium to monitor protein release over 8 days. Furthermore, the different fibrin scaffolds were morphologically characterized. Results show that leukocyte-free fibrin matrices were homogenous while leukocyte-containing ones were heterogeneous, loose and cellular. Leukocyte incorporation produced a significant increase in the contents of proinflammatory cytokines interleukin (IL)-1β and IL-16 but not in the platelet-derived growth factors release (<1.5-fold). Surprisingly, the availability of vascular endothelial growth factor suffered an important decrease after 3 days of incubation in the case of L-PRP matrices. While the release of proinflammatory cytokines was almost absent or very low from PRGF-Endoret, the inclusion of leukocytes induced a major increase in these cytokines, which was characterized by the presence of a latent period. The PRGF-Endoret matrices were stable during the 8 days of incubation. The inclusion of leukocytes alters the growth factors release profile and also increased the dose of proinflammatory cytokines. © 2014 Wiley Periodicals, Inc.

Tracking rare-isotope beams with microchannel plates

DOE PAGES

Rogers, A. M.; Sanetullaev, A.; Lynch, W. G.; ...

2015-06-06

A system of two microchannel-plate detectors has been successfully implemented for tracking projectile-fragmentation beams. The detectors provide interaction positions, angles, and arrival Limes of ions at the reaction target. Furthermore, the current design is an adaptation of an assembly used for low-energy beams (~1.4 MeV/nucleon). In order to improve resolution in tracking high-energy heavy-ion beams, the magnetic field strength between the secondary-electron accelerating foil and the microchannel plate had to be increased substantially. Results from an experiment using a 37-MeV/nucleon 56Ni beam show that the tracking system can achieve sub-nanosecond timing resolution and a position resolution of ~1 mm formore » beam intensities up to 5 x 10 5 pps.« less

An advanced arc track resistant airframe wire

NASA Technical Reports Server (NTRS)

Beatty, J.

1995-01-01

Tensolite, a custom cable manufacturer specializing in high temperature materials as the dielectric medium, develops an advance arc track resistant airframe wire called Tufflite 2000. Tufflite 2000 has the following advantages over the other traditional wires: lighter weight and smaller in diameter; excellent wet and dry arc track resistance; superior dynamic cut-through performance even at elevated temperatures; flight proven performance on Boeing 737 and 757 airplanes; and true 260 C performance by utilizing Nickel plated copper conductors. This paper reports the different tests performed on Tufflite 2000: accelerated aging, arc resistance (wet and dry), dynamic cut through, humidity resistance, wire-to-wire abrasion, flammability, smoke, weight, notch sensitivity, flexibility, and markability. It particularly focuses on the BSI (British Standards Institute) dry arc resistance test and BSI wet arc tracking.

Tracking rare-isotope beams with microchannel plates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rogers, A. M.; Sanetullaev, A.; Lynch, W. G.

A system of two microchannel-plate detectors has been successfully implemented for tracking projectile-fragmentation beams. The detectors provide interaction positions, angles, and arrival Limes of ions at the reaction target. Furthermore, the current design is an adaptation of an assembly used for low-energy beams (~1.4 MeV/nucleon). In order to improve resolution in tracking high-energy heavy-ion beams, the magnetic field strength between the secondary-electron accelerating foil and the microchannel plate had to be increased substantially. Results from an experiment using a 37-MeV/nucleon 56Ni beam show that the tracking system can achieve sub-nanosecond timing resolution and a position resolution of ~1 mm formore » beam intensities up to 5 x 10 5 pps.« less

Altered mitochondrial function and oxidative stress in leukocytes of anorexia nervosa patients.

PubMed

Victor, Victor M; Rovira-Llopis, Susana; Saiz-Alarcon, Vanessa; Sangüesa, Maria C; Rojo-Bofill, Luis; Bañuls, Celia; Falcón, Rosa; Castelló, Raquel; Rojo, Luis; Rocha, Milagros; Hernández-Mijares, Antonio

2014-01-01

Anorexia nervosa is a common illness among adolescents and is characterised by oxidative stress. The effects of anorexia on mitochondrial function and redox state in leukocytes from anorexic subjects were evaluated. A multi-centre, cross-sectional case-control study was performed. Our study population consisted of 20 anorexic patients and 20 age-matched controls, all of which were Caucasian women. Anthropometric and metabolic parameters were evaluated in the study population. To assess whether anorexia nervosa affects mitochondrial function and redox state in leukocytes of anorexic patients, we measured mitochondrial oxygen consumption, membrane potential, reactive oxygen species production, glutathione levels, mitochondrial mass, and complex I and III activity in polymorphonuclear cells. Mitochondrial function was impaired in the leukocytes of the anorexic patients. This was evident in a decrease in mitochondrial O2 consumption (P<0.05), mitochondrial membrane potential (P<0.01) and GSH levels (P<0.05), and an increase in ROS production (P<0.05) with respect to control subjects. Furthermore, a reduction of mitochondrial mass was detected in leukocytes of the anorexic patients (P<0.05), while the activity of mitochondrial complex I (P<0.001), but not that of complex III, was found to be inhibited in the same population. Oxidative stress is produced in the leukocytes of anorexic patients and is closely related to mitochondrial dysfunction. Our results lead us to propose that the oxidative stress that occurs in anorexia takes place at mitochondrial complex I. Future research concerning mitochondrial dysfunction and oxidative stress should aim to determine the physiological mechanism involved in this effect and the physiological impact of anorexia.

Improving GOCE cross-track gravity gradients

NASA Astrophysics Data System (ADS)

Siemes, Christian

2018-01-01

The GOCE gravity gradiometer measured highly accurate gravity gradients along the orbit during GOCE's mission lifetime from March 17, 2009, to November 11, 2013. These measurements contain unique information on the gravity field at a spatial resolution of 80 km half wavelength, which is not provided to the same accuracy level by any other satellite mission now and in the foreseeable future. Unfortunately, the gravity gradient in cross-track direction is heavily perturbed in the regions around the geomagnetic poles. We show in this paper that the perturbing effect can be modeled accurately as a quadratic function of the non-gravitational acceleration of the satellite in cross-track direction. Most importantly, we can remove the perturbation from the cross-track gravity gradient to a great extent, which significantly improves the accuracy of the latter and offers opportunities for better scientific exploitation of the GOCE gravity gradient data set.

Heat-sterilized PD fluid blocks leukocyte adhesion and increases flow velocity in rat peritoneal venules.

PubMed

Jonasson, P; Bagge, U; Wieslander, A; Braide, M

1996-01-01

Data from cell culture experiments indicate that heat sterilization of peritoneal dialysis (PD) fluids produces cytotoxic glucose degradation products. The present vital microscopic study investigated the effects of different sterilization methods on the biocompatibility of PD fluids. Thus, heat-sterilized (commercially obtained and experimentally produced) and filter-sterilized PD fluids (pH = 5.30-5.40; 1.5% glucose) were compared with Tyrode buffer, with respect to the effects on microvascular blood flow velocity and leukocyte adhesion in the rat mesentery. Exteriorization of the mesentery produced a mild inflammation, known from the literature and characterized by the adhesive rolling of leukocytes along venular walls. Superfusion of the mesentery with filter-sterilized PD fluid had no significant effects on leukocyte rolling or flow velocity in venules 25-40 microns in diameter compared with buffer superfusion. Heat-sterilized PD fluid decreased the concentration of rolling leukocytes and increased flow velocity significantly, as compared with buffer and filter-sterilized PD fluid. The results indicate that heat sterilization of PD fluids produces substances that interact with microvascular tone and leukocyte-endothelial adhesion, which hypothetically could impair the acute, granulocyte-mediated defense against bacterial infections.

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.

Triggering of leukocytes by phase contrast in imaging cytometry with scanning fluorescence microscope (SFM)

NASA Astrophysics Data System (ADS)

Bocsi, József; Pierzchalski, Arkadiusz; Marecka, Monika; Malkusch, Wolf; Tárnok, Attila

2009-02-01

Slide-based cytometry (SBC) leads to breakthrough in cytometry of cells in tissues, culture and suspension. Carl Zeiss Imaging Solutions' new automated SFM combines imaging with cytometry. A critical step in image analysis is selection of appropriate triggering signal to detect all objects. Without correct target cell definition analysis is hampered. DNA-staining is among the most common triggering signals. However, the majority of DNA-dyes yield massive spillover into other fluorescence channels limiting their application. By microscopy objects of >5μm diameter can be easily detected by phase-contrast signal (PCS) without any staining. Aim was to establish PCS - triggering for cell identification. Axio Imager.Z1 motorized SFM was used (high-resolution digital camera, AxioCam MRm; AxioVision software: automatic multi-channel scanning, analysis). Leukocytes were stained with FITC (CD4, CD8) and APC (CD3) labelled antibodies in combinations using whole blood method. Samples were scanned in three channels (PCS/FITC/APC). Exposition-times for PCS were set as low as possible; the detection efficiency was verified by fluorescence. CD45-stained leukocytes were counted and compared to the number of PCS detected events. Leukocyte subtyping was compared with other cytometers. In focus the PCS of cells showed ring-form that was not optimal for cell definition. Out of focus PCS allows more effective qualitative and quantitative cell analyses. PCS was an accurate triggering signal for leukocytes enabling cell counting and discrimination of leukocytes from platelets. Leukocyte subpopulation frequencies were comparable to those obtained by other cytometers. In conclusion PCS is a suitable trigger-signal not interfering with fluorescence detection.

No difference in sensitivity for occult infection between tropolone- and oxine-labeled indium-111 leukocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Datz, F.L.; Bedont, R.A.; Baker, W.J.

1985-05-01

There is considerable disagreement as to whether oxine or tropolone is the best labeling agent for indium leukocytes. The authors have previously looked at the sensitivity of oxine-labeled /sup 111/In leukocyte scans for occult infections and now present a similar group of patients imaged with tropolone-labeled /sup 111/In leukocytes. Thirty-four patients (38 studies) with possible occult infection were prospectively studied. Patients were imaged 1-4 hr after injection and again at 24 hr postinjection. The differences in sensitivity between oxine and tropolone when imaged early and at 24 hr were not statistically significant. They conclude that there is not significant differencemore » in the ability to detect infection between oxine- and tropolone-labeled leukocytes, both early at 1-4 hr, and on delayed imaging 24 hr after injection.« less

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.

Leukocytes Are Recruited through the Bronchial Circulation to the Lung in a Spontaneously Hypertensive Rat Model of COPD

PubMed Central

Davis, Benjamin B.; Shen, Yi-Hsin; Tancredi, Daniel J.; Flores, Vanessa; Davis, Ryan P.; Pinkerton, Kent E.

2012-01-01

Chronic obstructive pulmonary disease (COPD) kills approximately 2.8 million people each year, and more than 80% of COPD cases can be attributed to smoking. Leukocytes recruited to the lung contribute to COPD pathology by releasing reactive oxygen metabolites and proteolytic enzymes. In this work, we investigated where leukocytes enter the lung in the early stages of COPD in order to better understand their effect as a contributor to the development of COPD. We simultaneously evaluated the parenchyma and airways for neutrophil accumulation, as well as increases in the adhesion molecules and chemokines that cause leukocyte recruitment in the early stages of tobacco smoke induced lung disease. We found neutrophil accumulation and increased expression of adhesion molecules and chemokines in the bronchial blood vessels that correlated with the accumulation of leukocytes recovered from the lung. The expression of adhesion molecules and chemokines in other vascular beds did not correlate with leukocytes recovered in bronchoalveolar lavage fluid (BALF). These data strongly suggest leukocytes are recruited in large measure through the bronchial circulation in response to tobacco smoke. Our findings have important implications for understanding the etiology of COPD and suggest that pharmaceuticals designed to reduce leukocyte recruitment through the bronchial circulation may be a potential therapy to treat COPD. PMID:22457750

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

An Adaptive 6-DOF Tracking Method by Hybrid Sensing for Ultrasonic Endoscopes

PubMed Central

Du, Chengyang; Chen, Xiaodong; Wang, Yi; Li, Junwei; Yu, Daoyin

2014-01-01

In this paper, a novel hybrid sensing method for tracking an ultrasonic endoscope within the gastrointestinal (GI) track is presented, and the prototype of the tracking system is also developed. We implement 6-DOF localization by sensing integration and information fusion. On the hardware level, a tri-axis gyroscope and accelerometer, and a magnetic angular rate and gravity (MARG) sensor array are attached at the end of endoscopes, and three symmetric cylindrical coils are placed around patients' abdomens. On the algorithm level, an adaptive fast quaternion convergence (AFQC) algorithm is introduced to determine the orientation by fusing inertial/magnetic measurements, in which the effects of magnetic disturbance and acceleration are estimated to gain an adaptive convergence output. A simplified electro-magnetic tracking (SEMT) algorithm for dimensional position is also implemented, which can easily integrate the AFQC's results and magnetic measurements. Subsequently, the average position error is under 0.3 cm by reasonable setting, and the average orientation error is 1° without noise. If magnetic disturbance or acceleration exists, the average orientation error can be controlled to less than 3.5°. PMID:24915179

Leukocyte telomere length is inversely associated with post-load but not with fasting plasma glucose levels.

PubMed

Khalangot, Mykola; Krasnienkov, Dmytro; Vaiserman, Alexander; Avilov, Ivan; Kovtun, Volodymir; Okhrimenko, Nadia; Koliada, Alexander; Kravchenko, Victor

2017-04-01

Type 2 diabetes mellitus is characterized by shorter leukocyte telomere length, but the relationship between leukocyte telomere length and type 2 diabetes mellitus development is rather questioned. Fasting and post-load glycaemia associated with different types of insulin resistance and their relation with leukocyte telomere length remains unknown. We compared leukocyte telomere length and fasting or post-load glucose levels in persons who do not receive glucose lowering treatment. For 82 randomly selected rural residents of Ukraine, aged 45+, not previously diagnosed with type 2 diabetes mellitus, the WHO oral glucose tolerance test and anthropometric measurements were performed. Leukocyte telomere length was measured by standardized method of quantitative monochrome multiplex polymerase chain reaction in real time. Spearman's or Pearson's rank correlation was used for correlation analysis between fasting plasma glucose or 2-h post-load plasma glucose levels and leukocyte telomere length. Logistical regression models were used to evaluate risks of finding short or long telomeres associated with fasting plasma glucose or 2-h post-load plasma glucose levels. No association of fasting plasma glucose and leukocyte telomere length was revealed, whereas 2-h post-load plasma glucose levels demonstrated a negative correlation ( P < 0.01) with leukocyte telomere length. Waist circumference and systolic blood pressure were negatively related ( P = 0.03) with leukocyte telomere length in men. Oral glucose tolerance test result-based glycemic categories did not show differences between mean leukocyte telomere length in categories of normal fasting plasma glucose and 2-h post-load plasma glucose (NGT, n = 33); diabetes mellitus (DM), n = 18 and impaired fasting glucose/tolerance (IFG/IGT, n = 31) levels. A correlation relationship between leukocyte telomere length and 2-h post-load plasma glucose level in NGT; IFG/IGT and DM groups ( P = 0.027; 0

Direct Leukocyte Migration across Pulmonary Arterioles and Venules into the Perivascular Interstitium of Murine Lungs during Bleomycin Injury and Repair

PubMed Central

Wang, Ping M.; Kachel, Diane L.; Cesta, Mark F.; Martin, William J.

2011-01-01

During acute lung injury and repair, leukocytes are thought to enter the lung primarily across alveolar capillaries and postcapillary venules. We hypothesized that leukocytes also migrate across pulmonary arterioles and venules, which serve as alternative sites for leukocyte influx into the lung during acute lung injury and repair. Lung sections from C57BL/6J mice up to 14 days after intratracheal bleomycin (3.33 U/kg) or saline instillation were assessed by light, fluorescence, confocal, and transmission electron microscopy for evidence of inflammatory cell sequestration and transmigration at these sites. After bleomycin treatment, large numbers of leukocytes (including neutrophils, eosinophils, and monocytes) were present in the vascular lumina and in perivascular interstitia of pulmonary arterioles and venules, as well as within the vascular walls. Leukocytes were observed within well-defined pathways in arteriolar walls and much less structured pathways in venular walls, apparently in the process of transmigration. Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were expressed at sites of leukocyte interaction with the luminal surface, especially in arterioles. Leukocytes appeared to exit from the vessels near collagen fibers into the perivascular interstitium. Results indicate that leukocytes can directly migrate across arteriolar and venular walls into the perivascular interstitium, which may represent an important but under-recognized pathway for leukocyte influx into the lung during injury and repair. PMID:21641381

Channel catfish (Ictalurus punctatus) leukocytes express estrogen receptor isoforms ERα and ERβ2 and are functionally modulated by estrogens.

PubMed

Iwanowicz, Luke R; Stafford, James L; Patiño, Reynaldo; Bengten, Eva; Miller, Norman W; Blazer, Vicki S

2014-09-01

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. Published by Elsevier Ltd.

Research of maneuvering target prediction and tracking technology based on IMM algorithm

NASA Astrophysics Data System (ADS)

Cao, Zheng; Mao, Yao; Deng, Chao; Liu, Qiong; Chen, Jing

2016-09-01

Maneuvering target prediction and tracking technology is widely used in both military and civilian applications, the study of those technologies is all along the hotspot and difficulty. In the Electro-Optical acquisition-tracking-pointing system (ATP), the primary traditional maneuvering targets are ballistic target, large aircraft and other big targets. Those targets have the features of fast velocity and a strong regular trajectory and Kalman Filtering and polynomial fitting have good effects when they are used to track those targets. In recent years, the small unmanned aerial vehicles developed rapidly for they are small, nimble and simple operation. The small unmanned aerial vehicles have strong maneuverability in the observation system of ATP although they are close-in, slow and small targets. Moreover, those vehicles are under the manual operation, therefore, the acceleration of them changes greatly and they move erratically. So the prediction and tracking precision is low when traditional algorithms are used to track the maneuvering fly of those targets, such as speeding up, turning, climbing and so on. The interacting multiple model algorithm (IMM) use multiple models to match target real movement trajectory, there are interactions between each model. The IMM algorithm can switch model based on a Markov chain to adapt to the change of target movement trajectory, so it is suitable to solve the prediction and tracking problems of the small unmanned aerial vehicles because of the better adaptability of irregular movement. This paper has set up model set of constant velocity model (CV), constant acceleration model (CA), constant turning model (CT) and current statistical model. And the results of simulating and analyzing the real movement trajectory data of the small unmanned aerial vehicles show that the prediction and tracking technology based on the interacting multiple model algorithm can get relatively lower tracking error and improve tracking precision

Direct and accelerated parameter mapping using the unscented Kalman filter.

PubMed

Zhao, Li; Feng, Xue; Meyer, Craig H

2016-05-01

To accelerate parameter mapping using a new paradigm that combines image reconstruction and model regression as a parameter state-tracking problem. In T2 mapping, the T2 map is first encoded in parameter space by multi-TE measurements and then encoded by Fourier transformation with readout/phase encoding gradients. Using a state transition function and a measurement function, the unscented Kalman filter can describe T2 mapping as a dynamic system and directly estimate the T2 map from the k-space data. The proposed method was validated with a numerical brain phantom and volunteer experiments with a multiple-contrast spin echo sequence. Its performance was compared with a conjugate-gradient nonlinear inversion method at undersampling factors of 2 to 8. An accelerated pulse sequence was developed based on this method to achieve prospective undersampling. Compared with the nonlinear inversion reconstruction, the proposed method had higher precision, improved structural similarity and reduced normalized root mean squared error, with acceleration factors up to 8 in numerical phantom and volunteer studies. This work describes a new perspective on parameter mapping by state tracking. The unscented Kalman filter provides a highly accelerated and efficient paradigm for T2 mapping. © 2015 Wiley Periodicals, Inc.

Quadrotor trajectory tracking using PID cascade control

NASA Astrophysics Data System (ADS)

Idres, M.; Mustapha, O.; Okasha, M.

2017-12-01

Quadrotors have been applied to collect information for traffic, weather monitoring, surveillance and aerial photography. In order to accomplish their mission, quadrotors have to follow specific trajectories. This paper presents proportional-integral-derivative (PID) cascade control of a quadrotor for path tracking problem when velocity and acceleration are small. It is based on near hover controller for small attitude angles. The integral of time-weighted absolute error (ITAE) criterion is used to determine the PID gains as a function of quadrotor modeling parameters. The controller is evaluated in three-dimensional environment in Simulink. Overall, the tracking performance is found to be excellent for small velocity condition.

Automated Tracking of Cell Migration with Rapid Data Analysis.

PubMed

DuChez, Brian J

2017-09-01

Cell migration is essential for many biological processes including development, wound healing, and metastasis. However, studying cell migration often requires the time-consuming and labor-intensive task of manually tracking cells. To accelerate the task of obtaining coordinate positions of migrating cells, we have developed a graphical user interface (GUI) capable of automating the tracking of fluorescently labeled nuclei. This GUI provides an intuitive user interface that makes automated tracking accessible to researchers with no image-processing experience or familiarity with particle-tracking approaches. Using this GUI, users can interactively determine a minimum of four parameters to identify fluorescently labeled cells and automate acquisition of cell trajectories. Additional features allow for batch processing of numerous time-lapse images, curation of unwanted tracks, and subsequent statistical analysis of tracked cells. Statistical outputs allow users to evaluate migratory phenotypes, including cell speed, distance, displacement, and persistence, as well as measures of directional movement, such as forward migration index (FMI) and angular displacement. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

SU-E-T-512: Electromagnetic Simulations of the Dielectric Wall Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uselmann, A; Mackie, T

Purpose: To characterize and parametrically study the key components of a dielectric wall accelerator through electromagnetic modeling and particle tracking. Methods: Electromagnetic and particle tracking simulations were performed using a commercial code (CST Microwave Studio, CST Inc.) utilizing the finite integration technique. A dielectric wall accelerator consists of a series of stacked transmission lines sequentially fired in synchrony with an ion pulse. Numerous properties of the stacked transmission lines, including geometric, material, and electronic properties, were analyzed and varied in order to assess their impact on the transverse and axial electric fields. Additionally, stacks of transmission lines were simulated inmore » order to quantify the parasitic effect observed in closely packed lines. Particle tracking simulations using the particle-in-cell method were performed on the various stacks to determine the impact of the above properties on the resultant phase space of the ions. Results: Examination of the simulation results show that novel geometries can shape the accelerating pulse in order to reduce the energy spread and increase the average energy of accelerated ions. Parasitic effects were quantified for various geometries and found to vary with distance from the end of the transmission line and along the beam axis. An optimal arrival time of an ion pulse relative to the triggering of the transmission lines for a given geometry was determined through parametric study. Benchmark simulations of single transmission lines agree well with published experimental results. Conclusion: This work characterized the behavior of the transmission lines used in a dielectric wall accelerator and used this information to improve them in novel ways. Utilizing novel geometries, we were able to improve the accelerating gradient and phase space of the accelerated particle bunch. Through simulation, we were able to discover and optimize design issues with the

Anethole and eugenol reduce in vitro and in vivo leukocyte migration induced by fMLP, LTB4, and carrageenan.

PubMed

Estevão-Silva, Camila Fernanda; Kummer, Raquel; Fachini-Queiroz, Fernanda Carolina; Grespan, Renata; Nogueira de Melo, Gessilda Alcântara; Baroni, Silmara; Cuman, Roberto Kenji Nakamura; Bersani-Amado, Ciomar Aparecida

2014-07-01

The aim of this study was to investigate the effect of anethole (AN) and eugenol (EUG) on leukocyte migration using in vitro chemotaxis and in situ microcirculation assays. BALB/c mice were used for the in vitro chemotaxis assay, and Wistar rats for the in situ microcirculation assay. We evaluated (a) the in vitro leukocyte migration in response to chemotactic factors (formyl-methionyl-leucyl-phenylalanine [fMLP] and leukotriene B4 [LTB4]) and (b) the rolling, adhesion, and migration of leukocytes induced by an injection of carrageenan (100 µg/cavity) into the scrotum of the animal. In the in vitro chemotaxis assay, AN and EUG at doses of 1, 3, 9, and 27 µg/ml significantly inhibited leukocyte migration when stimulated by the chemotactic agents fMLP and LTB4. In the in situ microcirculation assay, AN at doses of 125 and 250 mg/kg and EUG at a dose of 250 mg/kg significantly decreased the number of leukocytes that rolled, adhered, and migrated to perivascular tissue. The results indicate that AN and EUG exert inhibitory effects on leukocyte migration, highlighting their possible use to diminish excessive leukocyte migration in the inflammatory process.

GPU COMPUTING FOR PARTICLE TRACKING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nishimura, Hiroshi; Song, Kai; Muriki, Krishna

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 calculationmore » 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.« less

A preliminary design of the collinear dielectric wakefield accelerator

NASA Astrophysics Data System (ADS)

Zholents, A.; Gai, W.; Doran, S.; Lindberg, R.; Power, J. G.; Strelnikov, N.; Sun, Y.; Trakhtenberg, E.; Vasserman, I.; Jing, C.; Kanareykin, A.; Li, Y.; Gao, Q.; Shchegolkov, D. Y.; Simakov, E. I.

2016-09-01

A preliminary design of the multi-meter long collinear dielectric wakefield accelerator that achieves a highly efficient transfer of the drive bunch energy to the wakefields and to the witness bunch is considered. It is made from 0.5 m long accelerator modules containing a vacuum chamber with dielectric-lined walls, a quadrupole wiggler, an rf coupler, and BPM assembly. The single bunch breakup instability is a major limiting factor for accelerator efficiency, and the BNS damping is applied to obtain the stable multi-meter long propagation of a drive bunch. Numerical simulations using a 6D particle tracking computer code are performed and tolerances to various errors are defined.

Monocular Stereo Measurement Using High-Speed Catadioptric Tracking

PubMed Central

Hu, Shaopeng; Matsumoto, Yuji; Takaki, Takeshi; Ishii, Idaku

2017-01-01

This paper presents a novel concept of real-time catadioptric stereo tracking using a single ultrafast mirror-drive pan-tilt active vision system that can simultaneously switch between hundreds of different views in a second. By accelerating video-shooting, computation, and actuation at the millisecond-granularity level for time-division multithreaded processing in ultrafast gaze control, the active vision system can function virtually as two or more tracking cameras with different views. It enables a single active vision system to act as virtual left and right pan-tilt cameras that can simultaneously shoot a pair of stereo images for the same object to be observed at arbitrary viewpoints by switching the direction of the mirrors of the active vision system frame by frame. We developed a monocular galvano-mirror-based stereo tracking system that can switch between 500 different views in a second, and it functions as a catadioptric active stereo with left and right pan-tilt tracking cameras that can virtually capture 8-bit color 512×512 images each operating at 250 fps to mechanically track a fast-moving object with a sufficient parallax for accurate 3D measurement. Several tracking experiments for moving objects in 3D space are described to demonstrate the performance of our monocular stereo tracking system. PMID:28792483

Effectiveness of leukocyte immunotherapy in primary recurrent spontaneous abortion (RSA).

PubMed

Gharesi-Fard, Behrouz; Zolghadri, Jaleh; Foroughinia, Leila; Tavazoo, Fahimeh; Samsami Dehaghani, Alamtaj

2007-09-01

Recurrent spontaneous abortion (RSA) is defined as three or more sequential abortions before the twentieth week of gestation. There are evidences to support an allo-immunologic mechanism for RSA. One of the methods for treatment of RSA is leukocyte therapy; however there is still controversy about effectiveness of this method. To evaluate the effectiveness of leukocyte therapy for treatment of RSA. Ninety two non-pregnant women with at least three sequential abortions (60 primary & 32 secondary aborters) recognized as RSA were referred to our Laboratory for immunotherapy. All the cases were immunized by isolated lymphocytes from their husbands. Fifty to 100 million washed and resuspended mononuclear cells were injected by I.V., S.C., and I.D. route. The result of each injection was checked by WBC cross matching between couples after four weeks of injections. Immunization was repeated in fifth week to a maximum of 3 times if needed. Eighty one age-matched non-pregnant RSA women (52 primary and 29 secondary aborters) with at least three sequential abortions were also included in this study as controls. The control group was not immunized. 67 out of 92 (72.8%) immunized cases and 44 out of 81 controls (54.3%) showed a successful outcome of pregnancy (p<0.02). Comparison of primary and secondary aborters indicated a significantly better outcome only in primary (75% vs. 42.3%. p<0.001) but not in secondary aborters (68.8% vs. 75.9%, p = 0.7). The present investigation showed the effectiveness of leukocyte therapy in primary but not in secondary RSA patients. Despite the current controversy and limitation of leukocyte therapy in RSA, the results of our investigation provide evidence supporting the use of allo-immunization in improving the outcome of pregnancy in primary RSA patients.

Mini Bypass and Proinflammatory Leukocyte Activation: A Randomized Controlled Trial.

PubMed

Nguyen, Bao A V; Fiorentino, Francesca; Reeves, Barnaby C; Baig, Kamran; Athanasiou, Thanos; Anderson, Jon R; Haskard, Dorian O; Angelini, Gianni D; Evans, Paul C

2016-04-01

Coronary artery bypass grafting (CABG) with conventional cardiopulmonary bypass (CPB) induces systemic inflammation. Miniaturized CPB may attenuate systemic inflammatory activation. The intracellular signaling pathways promoting inflammation in cardiac operations and the relative effects of CPB on these processes are uncertain. In this study, induction of reactive oxygen species (ROS) and activation of nuclear factor (NF)-κB, p38 mitogen-activated protein kinase (MAPK) within leukocytes, and leukocyte accumulation in cantharidin-induced blisters was compared in patients exposed to miniaturized CPB (mCPB) and those who underwent conventional CPB (cCPB). Patients undergoing CABG were randomized to receive either cCPB (n = 13) or mCPB (n = 13). Blood samples were collected preoperatively and 5 times after initiating CPB (up to 5 hours) and analyzed by flow cytometry for intracellular markers of activation (ROS, p38-MAPK, and NF-κB phosphorylation). ROS in lymphocytes were elevated in cCPB compared with mCPB (p < 0.01), whereas ROS in granulocytes and monocytes were similar between groups. After initiation of CPB, p38-MAPK was higher in patients receiving cCPB compared with those receiving mCPB (p < 0.05). NF-κB phosphorylation in leukocyte subsets was similar in patients exposed to cCPB and those exposed to mCPB. Leukocyte accumulation in cantharidin-induced blisters, white cell counts, and serum C-reactive protein (CRP) was enhanced in response to cardiac operations, but no differences were observed between mCPB and cCPB groups. Postoperative serum creatinine levels were reduced in the mCPB group compared with the cCPB group (p < 0.05). Both p38-MAPK activation and ROS were attenuated with the use of mCPB compared with cCPB, providing a potential mechanism for reduced inflammation in association with CPB miniaturization. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Glucocorticoid receptor expression on circulating leukocytes in healthy and asthmatic adolescents in response to exercise

PubMed Central

Lu, Kim D.; Cooper, Dan; Haddad, Fadia; Zaldivar, Frank; Kraft, Monica; Radom-Aizik, Shlomit

2017-01-01

Background Poor aerobic fitness is associated with worsening of asthma symptoms and fitness training may improve asthma control. The mechanism linking fitness with asthma is not known. We hypothesized that repeated bouts of exercise would lead to a downregulation of glucocorticoid receptor (GR) expression on circulating leukocytes reflecting a reduced responsiveness to stress. Methods In a prospective exercise training intervention of healthy and asthmatic adolescents, GR expression in leukocytes was measured using flow cytometry in response to a brief exercise challenge before and after the training intervention. PBMC gene expression of GR, GRβ, HSP70, and TGFβ1, 2 were determined using RT-PCR. Results Peak V̇O2 increased by 14.6 ± 2.3% indicating an effective training (p<0.01). There was a significant difference in GR expression among leukocyte subtypes, with highest expression in eosinophils. Following the training intervention, there was a significant decrease in baseline GR expression (p<0.05) in leukocyte and monocyte subtypes in both healthy and asthmatic adolescents. Conclusions This is the first study in adolescents to show that exercise training reduces GR expression on circulating leukocytes. We speculate that exercise training downregulates the stress response in general, manifested by decreased GR expression, and may explain why improving fitness improves asthma health. PMID:28796240

Polarized e-bunch acceleration at Cornell RCS: Tentative tracking simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meot, F.; Ptitsyn, V.; Ranjbar, V.

2017-10-19

An option as an injector into eRHIC electron storage ring is a rapid-cyclic synchrotron (RCS). Rapid acceleration of polarized electron bunches has never been done, Cornell synchrotron might lend itself to dedicated tests, which is to be first explored based on numerical investigations. This paper is a very preliminary introduction to the topic.

Effect of GNSS receiver carrier phase tracking loops on earthquake monitoring performance

NASA Astrophysics Data System (ADS)

Clare, Adam; Lin, Tao; Lachapelle, Gérard

2017-06-01

This research focuses on the performance of GNSS receiver carrier phase tracking loops for early earthquake monitoring systems. An earthquake was simulated using a hardware simulator and position, velocity and acceleration displacements were obtained to recreate the dynamics of the 2011 Tohoku earthquake. Using a software defined receiver, GSNRx, tracking bandwidths of 5, 10, 15, 20, 30, 40 and 50 Hz along with integration times of 1, 5 and 10 ms were tested. Using the phase lock indicator, an adaptive tracking loop was designed and tested to maximize performance for this application.

Endothelial gaps and adherent leukocytes in allergen-induced early- and late-phase plasma leakage in rat airways.

PubMed Central

Baluk, P.; Bolton, P.; Hirata, A.; Thurston, G.; McDonald, D. M.

1998-01-01

Exposure of sensitized individuals to antigen can induce allergic responses in the respiratory tract, manifested by early and late phases of vasodilatation, plasma leakage, leukocyte influx, and bronchoconstriction. Similar responses can occur in the skin, eye, and gastrointestinal tract. The early-phase response involves mast cell mediators and the late-phase response is leukocyte dependent, but the mechanism of leakage is not understood. We sought to identify the leaky blood vessels, to determine whether these vessels contained endothelial gaps, and to analyze the relationship of the gaps to adherent leukocytes, using biotinylated lectins or silver nitrate to stain the cells in situ and Monastral blue as a tracer to quantify plasma leakage. Most of the leakage occurred in postcapillary venules (< 40-microns diameter), whereas most of the leukocyte migration (predominantly neutrophils) occurred in collecting venules. Capillaries and arterioles did not leak. Endothelial gaps were found in the leaky venules, both by silver nitrate staining and by scanning electron microscopy, and 94% of the gaps were distinct from sites of leukocyte adhesion or migration. We conclude that endothelial gaps contribute to both early and late phases of plasma leakage induced by antigen, but most leakage occurs upstream to sites of leukocyte adhesion. Images Figure 3 Figure 5 Figure 6 Figure 7 PMID:9626051

Sensitivity and specificity of blood leukocyte counts as an indicator of mortality in horses after colic surgery.

PubMed

Salciccia, A; Sandersen, C; Grulke, S; de la Rebière de Pouyade, G; Caudron, I; Serteyn, D; Detilleux, J

2013-09-21

The objectives of this study were to describe and relate perioperative changes in blood leukocyte counts to the outcome of surgical colic horses, determine a cut-off value in the early postoperative period to obtain an indicator of the outcome, and compare the obtained value to a validation population of horses. Fifty-three horses undergoing colic surgery were included in the descriptive part of the study. Total leukocyte counts were performed before, during and serially after surgery. A receiver operating characteristic analysis was performed on the leukocyte counts of 45 of these horses to determine a cut-off value for the outcome. The results obtained were validated on a second set of 50 horses that underwent colic surgery in similar conditions. The kinetics of blood leukocytes in survivors was higher than in non-survivors during the first days. Non-survivor horses were more likely to have at least one blood leukocyte count ≤ 3.9 × 10(3)/mm(3) between 28 and 60 hours after surgery than survivor horses. This cut-off value was confirmed in the validation population. These results suggest that routine values of blood leukocyte counts can be used as an additional prognostic indicator after colic surgery alongside other predictors previously associated with the outcome.

[The use of programmed microcalculators for automation of leukocyte count].

PubMed

Plykin, D L

1989-01-01

Soviet programmed microcalculators are recommended to be used for the calculation of the leukocytic formulae when making serial blood analyses at clinical laboratories. The suggested program helps completely automate the process of estimating the leukocyte types, detectable in microscopic examination of the blood smears; the results may be obtained as a per cent ratio of the cells (a form most prevalent nowadays) and as their quantity per microliter of blood. The presence of service elements in the program essentially simplifies the work, making it convenient for an untrained user of the microcalculator. Since commercial Soviet programmed microcalculators somewhat differ in the systems of program steps, two variants of the program are suggested, adapted to the two most prevalent designs.

PHENOTYPIC EXPRESSIONS OF THE MAJOR HISTOCOMPATIBILITY LOCUS IN MAN (HL-A): LEUKOCYTE ANTIGENS AND MIXED LEUKOCYTE CULTURE REACTIVITY

PubMed Central

Amos, D. Bernard; Bach, Fritz H.

1968-01-01

The evidence is reviewed that a single genetic system, the major histocompatibility locus in man, HL-A, determines most of the antigens measured by presently available leukocyte isoantisera, and also controls reactivity in one-way mixed leucocyte culture tests. Studies in 12 families are presented to support this conclusion. Some interesting exceptions to the general typing—MLC tests correlation are presented and discussed. PMID:5675436

Increased leukocyte adhesion to vascular endothelium in preeclampsia is inhibited by antioxidants.

PubMed

Ryu, Seongho; Huppmann, Alison R; Sambangi, Nirmala; Takacs, Peter; Kauma, Scott W

2007-04-01

To test the hypothesis that plasma from women with preeclampsia increases leukocyte adhesion to vascular endothelial cells and that antioxidants inhibit this effect. Plasma from 12 women with severe preeclampsia and 12 with normal pregnancy was tested in an in vitro leukocyte-endothelium adhesion assay in the presence or absence of vitamin E, vitamin C, or N-acetylcysteine. Preeclamptic plasma significantly increased monocyte (U937 cells) and T-cell (Jurkat) adhesion to human umbilical vein (HUVEC) and microvascular endothelial cells, compared with normal pregnant plasma. The antioxidants vitamin E, vitamin C, and N-acetylcysteine significantly inhibited monocyte adhesion to HUVEC in the presence of preeclamptic but not normal pregnant plasma. Increased adhesion in response to preeclamptic plasma was not mediated through a protein kinase C (PKC) mechanism, because the PKC inhibitor bisindolylmaleimide I had no effect on adhesion in the presence of preeclamptic plasma. Severe preeclampsia is associated with increased leukocyte-endothelium adhesion and clinically useful antioxidants can inhibit this effect.

Design of four-beam IH-RFQ linear accelerator

NASA Astrophysics Data System (ADS)

Ikeda, Shota; Murata, Aki; Hayashizaki, Noriyosu

2017-09-01

The multi-beam acceleration method is an acceleration technique for low-energy high-intensity heavy ion beams, which involves accelerating multiple beams to decrease space charge effects, and then integrating these beams by a beam funneling system. At the Tokyo Institute of Technology a two beam IH-RFQ linear accelerator was developed using a two beam laser ion source with direct plasma injection scheme. This system accelerated a carbon ion beam with a current of 108 mA (54 mA/channel × 2) from 5 up to 60 keV/u. In order to demonstrate that a four-beam IH-RFQ linear accelerator is suitable for high-intensity heavy ion beam acceleration, we have been developing a four-beam prototype. A four-beam IH-RFQ linear accelerator consists of sixteen RFQ electrodes (4 × 4 set) with stem electrodes installed alternately on the upper and lower ridge electrodes. As a part of this development, we have designed a four-beam IH-RFQ linear accelerator using three dimensional electromagnetic simulation software and beam tracking simulation software. From these simulation results, we have designed the stem electrodes, the center plate and the side shells by evaluating the RF properties such as the resonance frequency, the power loss and the electric strength distribution between the RFQ electrodes.

Photoperiod affects the expression of sex and species differences in leukocyte number and leukocyte trafficking in congeneric hamsters.

PubMed

Bilbo, S D; Dhabhar, F S; Viswanathan, K; Saul, A; Nelson, R J

2003-11-01

Sex differences in immune function are well documented. These sex differences may be modulated by social and environmental factors. Individuals of polygynous species generally exhibit more pronounced sex differences in immune parameters than individuals of monogamous species, often displaying an energetic trade-off between enhanced immunity and high mating success. During winter, animals contend with environmental conditions (e.g. low temperatures and decreased food availability) that evoke energetic-stress responses; many mammals restrict reproduction in response to photoperiod as part of an annual winter coping strategy. To test the hypothesis that extant sex and species differences in immune surveillance may be modulated by photoperiod, we examined leukocyte numbers in males and females of two closely related hamster species (Phodopus). As predicted, uniparental P. sungorus exhibited a robust sex difference, with total white blood cells, total lymphocytes, T cells, and B cells higher in females than males, during long days when reproduction occurs, but not during short days when reproduction usually stops. In contrast, biparental male and female P. campbelli exhibited comparable leukocyte numbers during both long and short days. To study sex differences in stress responses, we also examined immune cell trafficking in response to an acute (2 h) restraint stressor. During stressful challenges, it appears beneficial for immune cells to exit the blood and move to primary immune defense areas such as the skin, in preparation for potential injury or infection. Acute stress moved lymphocytes and monocytes out of the blood in all animals. Blood cortisol concentrations were increased in P. sungorus females compared to males at baseline (52%) and in response to restraint stress (38%), but only in long days. P. campbelli males and females exhibited comparable blood cortisol and stress responses during both long and short days. Our results suggest that interactions among

Enhancement of tracking performance in electro-optical system based on servo control algorithm

NASA Astrophysics Data System (ADS)

Choi, WooJin; Kim, SungSu; Jung, DaeYoon; Seo, HyoungKyu

2017-10-01

Modern electro-optical surveillance and reconnaissance systems require tracking capability to get exact images of target or to accurately direct the line of sight to target which is moving or still. This leads to the tracking system composed of image based tracking algorithm and servo control algorithm. In this study, we focus on the servo control function to minimize the overshoot in the tracking motion and do not miss the target. The scheme is to limit acceleration and velocity parameters in the tracking controller, depending on the target state information in the image. We implement the proposed techniques by creating a system model of DIRCM and simulate the same environment, validate the performance on the actual equipment.

Development of feedforward control in a dynamic manual tracking task.

PubMed

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 the target's motion. The ability to track the target at higher velocities increased, and the application of a feedback-based step-and-hold strategy decreased with age, as shown by increases in maximum target velocity and decreases in number of stops between ages 6-7 and 8-9 and between ages 8-9 and 10-11. The ability to exploit feedforward control in a dynamic tracking task improves significantly with age.

Leukocyte Cell–Derived Chemotaxin 2–Associated Amyloidosis: A Recently Recognized Disease with Distinct Clinicopathologic Characteristics

PubMed Central

Dogan, Ahmet; Larsen, Christopher P.

2015-01-01

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

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. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Mechanisms of the priming effect of low doses of lipopoly-saccharides on leukocyte-dependent platelet aggregation in whole blood.

PubMed

Montrucchio, Giuseppe; Bosco, Ornella; Del Sorbo, Lorenzo; Fascio Pecetto, Paolo; Lupia, Enrico; Goffi, Alberto; Omedè, Paola; Emanuelli, Giorgio; Camussi, Giovanni

2003-11-01

Several studies focused on the ability of bacterial lipopolysac-charides (LPS) in triggering platelet and/or leukocyte activation. The aim of this study was to investigate the molecular mechanisms involved in the aggregation of platelets and in their interaction with leukocytes in whole blood after stimulation with low doses of LPS. LPS did not directly induce platelet aggregation in whole blood, but they primed the aggregation of platelets induced by epinephrine, adenosine diphosphate and arachidonic acid. As shown by cytofluorimetry, platelets neither bind FITC-LPS, nor express the LPS-receptors CD14 and toll-like receptor 4 (TLR4). On the contrary, LPS primed monocytes and to a lesser extent polymorphonuclear neutrophils to adhere to platelets. Both platelet-leukocyte interaction and platelet aggregation in whole blood were inhibited by blockade of CD14 and TLR4. Moreover, the interaction between platelets and leukocytes was inhibited by P-selectin, and by blockade of PAF and reactive oxygen species, suggesting a role of P-selectin and of leukocyte-derived mediators. In conclusion, these results elucidate the mechanisms leading to platelet activation and interaction with leukocytes triggered by LPS. They suggest that the activation of platelets by LPS is mainly dependent on leukocytes and especially monocytes as a result of CD14 and TLR4 engagement. Moreover, we found that leukocyte-platelet interaction was triggered by the synthesis of PAF and the generation of oxygen radicals that induced upregulation of surface expression of P-selectin.

Comparison of oxidative stress & leukocyte activation in patients with severe sepsis & burn injury

PubMed Central

Mühl, Diana; Woth, Gábor; Drenkovics, Livia; Varga, Adrienn; Ghosh, Subhamay; Csontos, Csaba; Bogár, Lajos; Wéber, György; Lantos, János

2011-01-01

Background & objectives: We evaluated pro- and anti-oxidant disturbances in sepsis and non-sepsis burn patients with systemic inflammatory response syndrome (SIRS). Adhesion molecules and inflammation markers on leukocytes were also analyzed. We hypothesized that oxidative stress and leukocyte activation markers can lead to the severity of sepsis. Methods: In 28 severe sepsis and 27 acute burn injury patients blood samples were collected at admission and 4 days consecutively. Oxidative stress markers: production of reactive oxygen species (ROS), myeloperoxidase, malondialdehyde and endogenous antioxidants: plasma protein sulphydryl groups, reduced glutathione, superoxide dismutase and catalase were measured. Flow cytometry was used to determine CD11a, CD14, CD18, CD49d and CD97 adhesion molecules on leukocytes. Procalcitonin, C-reactive protein, fibrinogen, platelet count and lactate were also analyzed. Results: Pro-oxidant parameters were significantly elevated in sepsis patients at admission, ROS intensity increased in burn patients until the 5th day. Endogenous antioxidant levels except catalase showed increased levels after burn trauma compared to sepsis. Elevated granulocyte activation and suppressed lymphocyte function were found at admission and early activation of granulocytes caused by increasing activation/migration markers in sepsis. Leukocyte adhesion molecule expression confirmed the suppressed lymphocyte and monocyte function in sepsis. Interpretation & conclusions: Severe sepsis is accompanied by oxidative stress and pathological leukocyte endothelial cell interactions. The laboratory parameters used for the evaluation of sepsis and several markers of pro- and antioxidant status were different between sepsis and non-sepsis burn patients. The tendency of changes in these parameters may refer to major oxidative stress in sepsis and developing SIRS in burns. PMID:21808137

Activation of lysosomal cathepsins in pregnant bovine leukocytes.

PubMed

Talukder, Md Abdus Shabur; Balboula, Ahmed Zaky; Shirozu, Takahiro; Kim, Sung Woo; Kunii, Hiroki; Suzuki, Toshiyuki; Ito, Tsukino; Kimura, Koji; Takahashi, Masashi

2018-06-01

In ruminants, interferon-tau (IFNT) - mediated expression of interferon-stimulated genes in peripheral blood leukocytes (PBLs) can indicate pregnancy. Recently, type 1 IFN-mediated activation of lysosomes and lysosomal cathepsins (CTSs) was observed in immune cells. This study investigated the status of lysosomal CTSs and lysosomes in PBLs collected from pregnant (P) and non-pregnant (NP) dairy cows, and conducted in vitro IFNT stimulation of NP blood leukocytes. Blood samples were collected 0, 7, 14 and 18 days post-artificial insemination, and the peripheral blood mononuclear cells (PBMCs) and polymorphonuclear granulocytes (PMNs) separated. The fluorescent activity of CTSB and CTSK in PMNs significantly increased with the progress of pregnancy, especially on day 18. In vitro supplementation of IFNT significantly increased the activities of CTSB and CTSK in NP PBMCs and PMNs. CTSB expression was significantly higher in PBMCs and PMNs collected from P day-18 cows than from NP cows, whereas there was no difference in CTSK expression. IFNT increased CTSB expression but did not affect CTSK expression. Immunodetection showed an increase of CTSB in P day-18 PBMCs and PMNs. In vitro stimulation of IFNT increased CTSB in NP PBMCs and PMNs. Lysosomal acidification showed a significant increase in P day-18 PBMCs and PMNs. IFNT also stimulated lysosomal acidification. Expressions of lysosome-associated membrane protein (LAMP) 1 and LAMP2 were significantly higher in P day-18 PBMCs and PMNs. The results suggest that pregnancy-specific activation of lysosomal functions by CTS activation in blood leukocytes is highly associated with IFNT during maternal and fetal recognition of pregnancy. © 2018 Society for Reproduction and Fertility.

Doppler tracking in time-dependent cosmological spacetimes

NASA Astrophysics Data System (ADS)

Giulini, Domenico; Carrera, Matteo

I will discuss the theoretical problems associated with Doppler tracking in time dependent background geometries, where ordinary Newtonian kinematics fails. A derivation of an exact general-relativistic formula for the two-way Doppler tracking of a spacecraft in homogeneous and isotropic Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetimes is presented, as well as a controlled approximation in McVittie spacetimes representing an FLRW background with a single spherically-symmetric inhomogeneity (e.g. a single star or black hole). The leading-order corrections of the acceleration as compared to the Newtonian expression are calculated, which are due to retardation and cosmological expansion and which in the Solar System turn out to be significantly below the scale (nanometer per square-second) set by the Pioneer Anomaly. Last, but not least, I discuss kinematical ambiguities connected with notions of "simultaneity" and "spatial distance", which, in principle, also lead to tracking corrections.

Measuring atmospheric density using GPS-LEO tracking data

NASA Astrophysics Data System (ADS)

Kuang, D.; Desai, S.; Sibthorpe, A.; Pi, X.

2014-01-01

We present a method to estimate the total neutral atmospheric density from precise orbit determination of Low Earth Orbit (LEO) satellites. We derive the total atmospheric density by determining the drag force acting on the LEOs through centimeter-level reduced-dynamic precise orbit determination (POD) using onboard Global Positioning System (GPS) tracking data. The precision of the estimated drag accelerations is assessed using various metrics, including differences between estimated along-track accelerations from consecutive 30-h POD solutions which overlap by 6 h, comparison of the resulting accelerations with accelerometer measurements, and comparison against an existing atmospheric density model, DTM-2000. We apply the method to GPS tracking data from CHAMP, GRACE, SAC-C, Jason-2, TerraSAR-X and COSMIC satellites, spanning 12 years (2001-2012) and covering orbital heights from 400 km to 1300 km. Errors in the estimates, including those introduced by deficiencies in other modeled forces (such as solar radiation pressure and Earth radiation pressure), are evaluated and the signal and noise levels for each satellite are analyzed. The estimated density data from CHAMP, GRACE, SAC-C and TerraSAR-X are identified as having high signal and low noise levels. These data all have high correlations with anominal atmospheric density model and show common features in relative residuals with respect to the nominal model in related parameter space. On the contrary, the estimated density data from COSMIC and Jason-2 show errors larger than the actual signal at corresponding altitudes thus having little practical value for this study. The results demonstrate that this method is applicable to data from a variety of missions and can provide useful total neutral density measurements for atmospheric study up to altitude as high as 715 km, with precision and resolution between those derived from traditional special orbital perturbation analysis and those obtained from onboard

Effects of Sex Steroids on Fish Leukocytes

PubMed Central

Cabas, Isabel

2018-01-01

In vertebrates, in addition to their classically reproductive functions, steroids regulate the immune system. This action is possible mainly due to the presence of steroid receptors in the different immune cell types. Much evidence suggests that the immune system of fish is vulnerable to xenosteroids, which are ubiquitous in the aquatic environment. In vivo and in vitro assays have amply demonstrated that oestrogens interfere with both the innate and the adaptive immune system of fish by regulating the main leukocyte activities and transcriptional genes. They activate nuclear oestrogen receptors and/or G-protein coupled oestrogen receptor. Less understood is the role of androgens in the immune system, mainly due to the complexity of the transcriptional regulation of androgen receptors in fish. The aim of this manuscript is to review our present knowledge concerning the effect of sex steroid hormones and the presence of their receptors on fish leukocytes, taking into consideration that the studies performed vary as regard the fish species, doses, exposure protocols and hormones used. Moreover, we also include evidence of the probable role of progestins in the regulation of the immune system of fish. PMID:29315244

Aberrant leukocyte telomere length in Birdshot Uveitis.

PubMed

Vazirpanah, Nadia; Verhagen, Fleurieke H; Rothova, Anna; Missotten, Tom O A R; van Velthoven, Mirjam; Den Hollander, Anneke I; Hoyng, Carel B; Radstake, Timothy R D J; Broen, Jasper C A; Kuiper, Jonas J W

2017-01-01

Birdshot Uveitis (BU) is an archetypical chronic inflammatory eye disease, with poor visual prognosis, that provides an excellent model for studying chronic inflammation. BU typically affects patients in the fifth decade of life. This suggests that it may represent an age-related chronic inflammatory disease, which has been linked to increased erosion of telomere length of leukocytes. To study this in detail, we exploited a sensitive standardized quantitative real-time polymerase chain reaction to determine the peripheral blood leukocyte telomere length (LTL) in 91 genotyped Dutch BU patients and 150 unaffected Dutch controls. Although LTL erosion rates were very similar between BU patients and healthy controls, we observed that BU patients displayed longer LTL, with a median of log (LTL) = 4.87 (= 74131 base pair) compared to 4.31 (= 20417 base pair) in unaffected controls (P<0.0001). The cause underpinning the difference in LTL could not be explained by clinical parameters, immune cell-subtype distribution, nor genetic predisposition based upon the computed weighted genetic risk score of genotyped validated variants in TERC, TERT, NAF1, OBFC1 and RTEL1. These findings suggest that BU is accompanied by significantly longer LTL.

Annexin A8 controls leukocyte recruitment to activated endothelial cells via cell surface delivery of CD63

NASA Astrophysics Data System (ADS)

Poeter, Michaela; Brandherm, Ines; Rossaint, Jan; Rosso, Gonzalo; Shahin, Victor; Skryabin, Boris V.; Zarbock, Alexander; Gerke, Volker; Rescher, Ursula

2014-04-01

To enable leukocyte adhesion to activated endothelium, the leukocyte receptor P-selectin is released from Weibel-Palade bodies (WPB) to the endothelial cell surface where it is stabilized by CD63. Here we report that loss of annexin A8 (anxA8) in human umbilical vein endothelial cells (HUVEC) strongly decreases cell surface presentation of CD63 and P-selectin, with a concomitant reduction in leukocyte rolling and adhesion. We confirm the compromised leukocyte adhesiveness in inflammatory-activated endothelial venules of anxA8-deficient mice. We find that WPB of anxA8-deficient HUVEC contain less CD63, and that this is caused by improper transport of CD63 from late multivesicular endosomes to WPB, with CD63 being retained in intraluminal vesicles. Consequently, reduced CD63 cell surface levels are seen following WPB exocytosis, resulting in enhanced P-selectin re-internalization. Our data support a model in which anxA8 affects leukocyte recruitment to activated endothelial cells by supplying WPB with sufficient amounts of the P-selectin regulator CD63.

Telomere Length in Leukocyte DNA in Gastric Cancer Patients and its Association with Clinicopathological Features and Prognosis.

PubMed

Tahara, Tomomitsu; Tahara, Sayumi; Horiguchi, Noriyuki; Kawamura, Tomohiko; Okubo, Masaaki; Ishizuka, Takamitsu; Yamada, Hyuga; Yoshida, Dai; Ohmori, Takafumi; Maeda, Kohei; Komura, Naruomi; Ikuno, Hirokazu; Jodai, Yasutaka; Kamano, Toshiaki; Nagasaka, Mitsuo; Nakagawa, Yoshihito; Tuskamoto, Tetsuya; Urano, Makoto; Shibata, Tomoyuki; Kuroda, Makoto; Ohmiya, Naoki

2017-04-01

Telomere shortening in leukocytes has been thought to be associated with reduced immune response capacity and increased chromosome instability. Several studies indicate that telomere length in the peripheral blood leukocyte DNA can predict clinical outcome of several cancers. We evaluated the potential association between telomere shortening in the leukocyte DNA and clinicopathological features and prognosis of gastric cancer (GC) in Japanese patients. Telomere length in leukocyte DNA was measured using quantitative real-time polymerase chain reaction (PCR) in 207 GC patients. The association between telomere length and clinicopathological features and prognosis was evaluated. These short-telomere group was significantly associated with advanced stage (p=0.015), worse overall survival (OS) and progression-free survival (PFS) (p=0.046 and 0.026, respectively). The same group was also weakly associated with overall and peritoneal recurrences (p=0.052 and 0.059, respectively). Telomere shortening in leukocyte DNA is associated with advanced stage and poor prognosis of GC, which may reflect their reduced immune response capacity or increased chromosome instability. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Acute effects of high- and low-intensity exercise bouts on leukocyte counts.

PubMed

Neves, Pedro Rogério Da Silva; Tenório, Thiago Ricardo Dos Santos; Lins, Tatiana Acioli; Muniz, Maria Tereza Cartaxo; Pithon-Curi, Tânia Cristina; Botero, João Paulo; Do Prado, Wagner Luiz

2015-06-01

It is widely accepted that physical exercise may bring about changes in the immune system. Even acute bouts of exercise can alter the number and function of leukocytes, but the degree of white blood cell trafficking depends on the intensity and duration of exercise. The aim of this study was to analyze the acute and short-term effects of exercise intensity on leukocyte counts and leukocyte subsets. Nine physically healthy, active young males (21.0 ± 1.9 years) underwent three experimental trials: high exercise intensity [80% peak oxygen consumption (VO 2peak )], low exercise intensity (40% VO 2peak ), and the control condition (no exercise). Blood samples were collected prior to exercise, immediately after exercise, and 2 hours after exercise. Two-way analysis of variance for repeated measures was used to evaluate differences between the trials and the time-points, and to compare times within trials. There was a greater increase in the leukocyte count after high-intensity exercise, compared to the control condition ( p  < 0.01) and low-intensity exercise ( p  < 0.01). This effect was still present 2 hours after passive recovery ( p  < 0.01). When the same participants were submitted to different exercise intensities, the acute and short-term effects of exercise on white blood cells were intensity-dependent immediately after exercise (i.e., lymphocytosis and monocytosis) and 2 hours after passive recovery (i.e., neutrophilia).

Altered circulating leukocytes and their chemokines in a clinical trial of therapeutic hypothermia for neonatal hypoxic ischemic encephalopathy*.

PubMed

Jenkins, Dorothea D; Lee, Timothy; Chiuzan, Cody; Perkel, Jessica K; Rollins, Laura Grace; Wagner, Carol L; Katikaneni, Lakshmi P; Bass, W Thomas; Kaufman, David A; Horgan, Michael J; Laungani, Sheela; Givelichian, Laurence M; Sankaran, Koravangatta; Yager, Jerome Y; Martin, Renee

2013-10-01

To determine systemic hypothermia's effect on circulating immune cells and their corresponding chemokines after hypoxic ischemic encephalopathy in neonates. In our randomized, controlled, multicenter trial of systemic hypothermia in neonatal hypoxic ischemic encephalopathy, we measured total and leukocyte subset and serum chemokine levels over time in both hypothermia and normothermia groups, as primary outcomes for safety. Neonatal ICUs participating in a Neurological Disorders and Stroke sponsored clinical trial of therapeutic hypothermia. Sixty-five neonates with moderate to severe hypoxic ischemic encephalopathy within 6 hours after birth. Patients were randomized to normothermia of 37°C or systemic hypothermia of 33°C for 48 hours. Complete and differential leukocyte counts and serum chemokines were measured every 12 hours for 72 hours. The hypothermia group had significantly lower median circulating total WBC and leukocyte subclasses than the normothermia group before rewarming, with a nadir at 36 hours. Only the absolute neutrophil count rebounded after rewarming in the hypothermia group. Chemokines, monocyte chemotactic protein-1 and interleukin-8, which mediate leukocyte chemotaxis as well as bone marrow suppression, were negatively correlated with their target leukocytes in the hypothermia group, suggesting active chemokine and leukocyte modulation by hypothermia. Relative leukopenia at 60-72 hours correlated with an adverse outcome in the hypothermia group. Our data are consistent with chemokine-associated systemic immunosuppression with hypothermia treatment. In hypothermic neonates, persistence of lower leukocyte counts after rewarming is observed in infants with more severe CNS injury.

SHI induced nano track polymer filters and characterization

NASA Astrophysics Data System (ADS)

Vijay, Y. K.

2009-07-01

Swift heavy ion irradiation produces damage in polymers in the form of latent tracks. Latent tracks can be enlarged by etching it in a suitable etchant and thus nuclear track etch membrane can be formed for gas permeation / purification in particular for hydrogen where the molecular size is very small. By applying suitable and controlled etching conditions well defined tracks can be formed for specific applications of the membranes. After etching gas permeation method is used for characterizing the tracks. In the present work polycarbonate (PC) of various thickness were irradiated with energetic ion beam at Inter University Accelerator Centre (IUAC), New Delhi. Nuclear tracks were modified by etching the PC in 6N NaOH at 60 (±1) °C from both sides for different times to produce track etch membranes. At critical etch time the etched pits from both the sides meet a rapid increase in gas permeation was observed. Permeability of hydrogen and carbon dioxide has been measured in samples etched for different times. The latent tracks produced by SHI irradiation in the track etch membranes show enhancement of free volume of the polymer. Nano filters are separation devices for the mixture of gases, different ions in the solution and isotopes and isobars separations. The polymer thin films with controlled porosity finding it self as best choice. However, the permeability and selectivity of these polymer based membrane filters are very important at the nano scale separation. The Swift Heavy Ion (SHI) induced nuclear track etched polymeric films with controlled etching have been attempted and characterized as nano scale filters.

[In-line leukocyte depletion ov thrombocytapheresis concentrates with the Fresenius-AS-104 cell separator].

PubMed

Zeiler, T; Kretschmer, V

1997-01-01

This study reports on in-line filtration of 72 platelet concentrates (PC) collected by the Fresenius AS 104 cell separator, using the new C4F sets with integrated leukocyte filters (Biofil P plus). 72 volunteer donors, automatic counts of platelets, microscopical counting of residual leukocytes with the Nageotte chamber, GMP-140 by flow cytometrie, beta-thromboglobulin release, platelet aggregation (ADP, collagen). Filtration reduced leukocytes by 98.5%. Residual leukocyte contamination remained clearly below 5 x 10(6) (mean 0.5 +/- 0.6 x 10(6), maximum 2.8 x 10(6). Platelet loss by filtration was found to be between 27.4 and 0.7% (median 8.5%). Filtration caused a significant decrease of platelet aggregability (p < 0.005), but no significant increase of beta-thromboglobulin release and only a slight decrease of GMP-140 expression. From these data can be concluded that in-line filtration was highly efficient with acceptable platelet retention. No significant platelet activation could be observed in the PC. The decrease of platelet aggregability have been due to the reduction of activated platelets which are believed to show reduced in vivo survival.

Lipids and leukocytes in newborn umbilical vein blood, birth weight and maternal body mass index.

PubMed

Brittos, T; de Souza, W B; Anschau, F; Pellanda, L

2016-12-01

Maternal obesity during pregnancy may influence fetal development and possibly predispose offspring to cardiovascular disease. The aim of the present study was to evaluate the relationship between maternal pre-pregnancy body mass index (BMI) and weight gain during pregnancy, and newborn birth weight, with lipid profile, high-sensitivity C-reactive protein (hs-CRP) and leukocyte in newborns. We performed a cross-sectional study of 245 mothers and their children. Blood was collected from the umbilical vein and assayed for lipid profile, hs-CRP and leukocyte count. Newborns average weight was 3241 g, total cholesterol 53.9 mg/dl, high-density lipoprotein cholesterol (HDL-c) 21.9 mg/dl, low-density lipoprotein cholesterol (LDL-c) 26.2 mg/dl, triglyceride 29.5 mg/dl and leukocytes 13,777/mm3. There was a direct correlation of pre-pregnancy BMI of overweight mothers with total cholesterol (r=0.220, P=0.037) and LDL-c (r=0.268, P=0.011) of newborns. Total cholesterol, LDL-c and HDL-c were higher in pre-term newborns (66.3±19.7, 35.9±14.6 and 25.2±7.7 mg/dl, respectively) that in full-term (52.4±13.1, 25.0±8.7 and 21.5±6.0 mg/dl), with P=0.001, 0.001 and 0.003, respectively. Leukocyte counts were higher in full-term newborns (14,268±3982/mm3) compared with pre-term (9792±2836/mm3, P<0.0001). There was a direct correlation between birth weight and leukocyte counts of newborns (r=0.282, P<0.0001). These results suggest the possible interaction of maternal weight and fetal growth with lipid metabolism and leukocyte count in the newborn, which may be linked to programming of the immune system.

In-111-labeled leukocytes in the diagnosis of rejection and cytomegalovirus infection in renal transplant patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forstrom, L.A.; Loken, M.K.; Cook, A.

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 0.6more » 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.« less

In-111-labeled leukocytes in the diagnosis of rejection and cytomegalovirus infection in renal transplant patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forstrom, L.A.; Loken, M.K.; Cook, A.

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 0.6more » 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.« less

Leukocyte Agglomeration Reaction in Diagnosis of Allergy Reactions from Antibiotics,

DTIC Science & Technology

tested in a clinic on 80 patients with serious allergic anamnesis . The results of the studies indicate that the leukocyte agglomeration reaction is a highly sensitive immunological indicator of hypersensitivity to antibiotics.

Characterisation of monoclonal antibodies specific for hamster leukocyte differentiation molecules.

PubMed

Rees, Jennifer; Haig, David; Mack, Victoria; Davis, William C

2017-01-01

Flow cytometry was used to identify mAbs that recognize conserved epitopes on hamster leukocyte differentiation molecules (hLDM) and also to characterize mAbs developed against hLDM. Initial screening of mAbs developed against LDMs in other species yielded mAbs specific for the major histocompatibility (MHC) II molecule, CD4 and CD18. Screening of sets of mAbs developed against hLDM yielded 22 new mAbs, including additional mAbs to MHC II molecules and mAbs that recognize LDMs expressed on all leukocytes, granulocytes, all lymphocytes, all T cells, a subset of T cells, or on all B cells. Based on comparison of the pattern of expression of LDMs expressed on all hamster leukocytes with the patterns of expression of known LDMs in other species, as detected by flow cytometry (FC), four mAbs are predicted to recognize CD11a, CD44, and CD45. Cross comparison of mAbs specific for a subset of hamster T cells with a cross reactive mAb known to recognize CD4 in mice and one recognising CD8 revealed they recognize CD4. The characterization of these mAbs expands opportunities to use hamsters as an additional model species to investigate the mechanisms of immunopathogenesis of infectious diseases. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Further comparisons of endogenous pyrogens and leukocytic endogenous mediators.

PubMed

Kampschmidt, R F; Upchurch, H F; Worthington, M L

1983-07-01

It was recently shown (Murphy et al., Infect. Immun. 34:177-183), that rabbit macrophages produce two biochemically and immunologically distinct endogenous pyrogens. One of these has or copurifies with substances having a molecular weight of 13,000 and a pI of 7.3. This protein was produced by blood monocytes or inflammatory cells elicited in 16-h rabbit peritoneal exudates. These acute peritoneal exudates were produced by the intraperitoneal injection of large volumes of saline containing shellfish glycogen. When the leukocytes in these exudates were washed and incubated at 37 degrees C in saline, they released an endogenous pyrogen. The injection of this pyrogen into rabbits, rats, or mice caused the biological manifestations which have been attributed to leukocytic endogenous mediator. These effects were increases in blood neutrophils, the lowering of plasma iron and zinc levels, and the increased synthesis of the acute-phase proteins. The other rabbit endogenous pyrogen seems to be a family of proteins with isoelectric points between 4.5 and 5.0. These proteins are produced by macrophages in the lung, liver, or in chronic peritoneal exudates. In these experiments, the lower-isoelectric-point endogenous pyrogens were produced by macrophages from the peritoneal cavity of rabbits that had been injected 4 days earlier with 50 ml of light mineral oil. These rabbit pyrogens were found to have leukocytic endogenous mediator activity in mice but to be completely inactive in rats. When injected into rabbits, these proteins produced fever, lowered plasma iron, increased blood neutrophils, but failed to elevate plasma fibrinogen.

Further comparisons of endogenous pyrogens and leukocytic endogenous mediators.

PubMed Central

Kampschmidt, R F; Upchurch, H F; Worthington, M L

1983-01-01

It was recently shown (Murphy et al., Infect. Immun. 34:177-183), that rabbit macrophages produce two biochemically and immunologically distinct endogenous pyrogens. One of these has or copurifies with substances having a molecular weight of 13,000 and a pI of 7.3. This protein was produced by blood monocytes or inflammatory cells elicited in 16-h rabbit peritoneal exudates. These acute peritoneal exudates were produced by the intraperitoneal injection of large volumes of saline containing shellfish glycogen. When the leukocytes in these exudates were washed and incubated at 37 degrees C in saline, they released an endogenous pyrogen. The injection of this pyrogen into rabbits, rats, or mice caused the biological manifestations which have been attributed to leukocytic endogenous mediator. These effects were increases in blood neutrophils, the lowering of plasma iron and zinc levels, and the increased synthesis of the acute-phase proteins. The other rabbit endogenous pyrogen seems to be a family of proteins with isoelectric points between 4.5 and 5.0. These proteins are produced by macrophages in the lung, liver, or in chronic peritoneal exudates. In these experiments, the lower-isoelectric-point endogenous pyrogens were produced by macrophages from the peritoneal cavity of rabbits that had been injected 4 days earlier with 50 ml of light mineral oil. These rabbit pyrogens were found to have leukocytic endogenous mediator activity in mice but to be completely inactive in rats. When injected into rabbits, these proteins produced fever, lowered plasma iron, increased blood neutrophils, but failed to elevate plasma fibrinogen. PMID:6862633

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

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

MiR-126 and miR-126* regulate shear-resistant firm leukocyte adhesion to human brain endothelium

PubMed Central

Cerutti, Camilla; Edwards, Laura J.; de Vries, Helga E.; Sharrack, Basil; Male, David K.; Romero, Ignacio A.

2017-01-01

Leukocyte adhesion to brain endothelial cells, the blood-brain barrier main component, is a critical step in the pathogenesis of neuroinflammatory diseases such as multiple sclerosis (MS). Leukocyte adhesion is mediated mainly by selectins, cell adhesion molecules and chemokines induced by pro-inflammatory cytokines such as TNFα and IFNγ, but the regulation of this process is not fully clear. This study investigated the regulation of firm leukocyte adhesion to human brain endothelium by two different brain endothelial microRNAs (miRs), miR-126 and miR-126*, that are downregulated by TNFα and IFNγ in a human brain endothelial cell line, hCMEC/D3. Using a leukocyte adhesion in vitro assay under shear forces mimicking blood flow, we observed that reduction of endothelial miR-126 and miR-126* enhanced firm monocyte and T cell adhesion to hCMEC/D3 cells, whereas their increased expression partially prevented THP1, Jurkat and primary MS patient-derived PBMC firm adhesion. Furthermore, we observed that miR-126* and miR-126 downregulation increased E-selectin and VCAM1, respectively, while miR-126 overexpression reduced VCAM1 and CCL2 expression by hCMEC/D3 cells, suggesting that these miRs regulate leukocyte adhesion by modulating the expression of adhesion-associated endothelial mRNA targets. Hence, human brain endothelial miR-126 and miR-126* could be used as a therapeutic tool to reduce leukocyte adhesion and thus reduce neuroinflammation. PMID:28358058

Reference values for maternal total and differential leukocyte counts in different trimesters of pregnancy and the initial postpartum period in western Turkey.

PubMed

Sanci, Muzaffer; Töz, Emrah; Ince, Onur; Özcan, Aykut; Polater, Kevser; Inan, Abdurrahman Hamdi; Beyan, Emrah; Akkaya, Emrah

2017-07-01

The aim of this study was to investigate alterations in the leukocyte and differential leukocyte counts in different trimesters of pregnancy and the initial postpartum period. The study population consisted of 40,325 pregnant women. A full blood count and automated differential leukocyte count were performed and all the haemogram results in the different trimesters of pregnancy were recorded. Percentiles were calculated using statistical software. A total of 82,786 complete blood count evaluations were performed in 40,325 subjects from the 6th to 41st week of pregnancy and in the initial postpartum period. The leukocyte counts increased from the 1st to the 3rd trimester and peaked in the initial postpartum period. Our reference values for the total and differential leukocyte counts may assist clinicians in distinguishing between leukocytosis and pathological elevation of the white blood cell count during pregnancy and the initial postpartum period. Impact statement Pregnancy requires profound adaptation by multiple systems to accommodate the demands of the developing foetus. Similar to all other systems, many haematological changes occur during pregnancy. Studies of normal variation in leukocyte counts were insufficient to distinguish normal from abnormal leukocyte counts during pregnancy and in the initial postpartum period, due to small numbers of patients and a lack of differential leukocyte counts. Without reference leukocyte levels, infections may be more difficult to assess during pregnancy and in the postpartum period. In this study, we report the 3rd, 5th, 10th, 50th, 95th and 99th percentile values for the total and differential leukocyte counts according to trimester in normal pregnancy and the initial postpartum period. Our reference values for the total and differential leukocyte counts in each trimester and the initial postpartum period may assist clinicians in distinguishing between normal leukocytosis and pathological elevation of the white blood

Beam energy tracking system on Optima XEx high energy ion implanter

DOE Office of Scientific and Technical Information (OSTI.GOV)

David, Jonathan; Satoh, Shu; Wu Xiangyang

2012-11-06

The Axcelis Optima XEx high energy implanter is an RF linac-based implanter with 12 RF resonators for beam acceleration. Even though each acceleration field is an alternating, sinusoidal RF field, the well known phase-focusing principle produces a beam with a sharp quasi-monoenergetic energy spectrum. A magnetic energy filter after the linac further attenuates the low energy continuum in the energy spectrum often associated with RF acceleration. The final beam energy is a function of the phase and amplitude of the 12 resonators in the linac. When tuning a beam, the magnetic energy filter is set to the desired energy, andmore » each linac parameter is tuned to maximize the transmission through the filter. Once a beam is set up, all the parameters are stored in a recipe, which can be easily tuned and has proven to be quite repeatable. The magnetic field setting of the energy filter selects the beam energy from the RF Linac accelerator, and in-situ verification of beam energy in addition to the magnetic energy filter setting has long been desired. An independent energy tracking system was developed for this purpose, using the existing electrostatic beam scanner as a deflector to construct an in-situ electrostatic energy analyzer. This paper will describe the system and performance of the beam energy tracking system.« less

The accelerated residency program: the Marshall University family practice 9-year experience.

PubMed

Petrany, Stephen M; Crespo, Richard

2002-10-01

In 1989, the American Board of Family Practice (ABFP) approved the first of 12 accelerated residency programs in family practice. These experimental programs provide a 1-year experience for select medical students that combines the requirements of the fourth year of medical school with those of the first year of residency, reducing the total training time by 1 year. This paper reports on the achievements and limitations of the Marshall University accelerated residency program over a 9-year period that began in 1992. Several parameters have been monitored since the inception of the accelerated program and provide the basis for comparison of accelerated and traditional residents. These include initial resident characteristics, performance outcomes, and practice choices. A total of 16 students were accepted into the accelerated track from 1992 through 1998. During the same time period, 44 residents entered the traditional residency program. Accelerated resident tended to be older and had more career experience than their traditional counterparts. As a group, the accelerated residents scored an average of 30 points higher on the final in-training exams provided by the ABFP. All residents in both groups remained at Marshall to complete the full residency training experience, and all those who have taken the ABFP certifying exam have passed. Accelerated residents were more likely to practice in West Virginia, consistent with one of the initial goals for the program. In addition, accelerated residents were more likely to be elected chief resident and choose an academic career than those in the traditional group. Both groups opted for small town or rural practice equally. The Marshall University family practice 9-year experience with the accelerated residency track demonstrates that for carefully selected candidates, the program can provide an overall shortened path to board certification and attract students who excel academically and have high leadership potential

Lagrangian acceleration statistics in a turbulent channel flow

NASA Astrophysics Data System (ADS)

Stelzenmuller, Nickolas; Polanco, Juan Ignacio; Vignal, Laure; Vinkovic, Ivana; Mordant, Nicolas

2017-05-01

Lagrangian acceleration statistics in a fully developed turbulent channel flow at Reτ=1440 are investigated, based on tracer particle tracking in experiments and direct numerical simulations. The evolution with wall distance of the Lagrangian velocity and acceleration time scales is analyzed. Dependency between acceleration components in the near-wall region is described using cross-correlations and joint probability density functions. The strong streamwise coherent vortices typical of wall-bounded turbulent flows are shown to have a significant impact on the dynamics. This results in a strong anisotropy at small scales in the near-wall region that remains present in most of the channel. Such statistical properties may be used as constraints in building advanced Lagrangian stochastic models to predict the dispersion and mixing of chemical components for combustion or environmental studies.

Pathology in rabbits treated with leukocyte-degraded meningococci in combination with meningococcal endotoxin.

PubMed Central

DeVoe, I W; Gilka, F; Gilchrist, J E; Yu, E

1977-01-01

The effects of a preparative dose of the leukocyte egesta containing degraded meningococci and a provocative dose of the meningococcal lipopolysaccharide on development of pathological lesions associated with disseminated intravascular coagulation were studied in tissues of 32 rabbits. These effects were compared with effects of a single dose of meningococcal lipopolysaccharide as well as leukocyte egesta containing degraded Staphylococcus epidermidis. Rabbits injected subcutaneously with egesta containing degraded meningococci followed after 12 h with meningococcal endotoxin (intravenously) exhibited heterophilic leukocytosis and disseminated intravascular coagulation mainly in the pulmonary capillaries and venules; focal necroses occurred in myocardium, lungs, and liver, whereas, cortical renal necrosis developed in lethal cases. Similar lesions, however, but less severe and with less frequency, developed even after a single dose of meningococcal endotoxin or after endotoxin that followed a dose of supernatant fluid from normal leukocytes. Our findings suggest that meningococcal material from polymorphonuclear degradation plays a role in the pathology characteristic of meningococcal septicemia. Images PMID:406202

Correcting coils in end magnets of accelerators

NASA Astrophysics Data System (ADS)

Kassab, L. R.; Gouffon, P.

1998-05-01

We present an empirical investigation of the correcting coils behavior used to homogenize the field distribution of the race-track microtron accelerator end magnets. These end magnets belong to the second stage of the 30.0 MeV cw electron accelerator under construction at IFUSP, the race-track microtron booster, in which the beam energy is raised from 1.97 to 5.1 MeV. The correcting coils are attached to the pole faces and are based on the inhomogeneities of the magnetic field measured. The performance of these coils, when operating the end magnets with currents that differ by +/-10% from the one used in the mappings that originated the coils copper leads, is presented. For one of the magnets, adjusting conveniently the current of the correcting coils makes it possible to homogenize field distributions of different intensities, once their shapes are practically identical to those that originated the coils. For the other one, the shapes are changed and the coils are less efficient. This is related to intrinsic factors that determine the inhomogeneities. However, we obtained uniformity of 0.001% in both cases.

Designing a Dielectric Laser Accelerator on a Chip

NASA Astrophysics Data System (ADS)

Niedermayer, Uwe; Boine-Frankenheim, Oliver; Egenolf, Thilo

2017-07-01

Dielectric Laser Acceleration (DLA) achieves gradients of more than 1GeV/m, which are among the highest in non-plasma accelerators. The long-term goal of the ACHIP collaboration is to provide relativistic (>1 MeV) electrons by means of a laser driven microchip accelerator. Examples of ’’slightly resonant” dielectric structures showing gradients in the range of 70% of the incident laser field (1 GV/m) for electrons with beta=0.32 and 200% for beta=0.91 are presented. We demonstrate the bunching and acceleration of low energy electrons in dedicated ballistic buncher and velocity matched grating structures. However, the design gradient of 500 MeV/m leads to rapid defocusing. Therefore we present a scheme to bunch the beam in stages, which does not only reduce the energy spread, but also the transverse defocusing. The designs are made with a dedicated homemade 6D particle tracking code.

Torque-based optimal acceleration control for electric vehicle

NASA Astrophysics Data System (ADS)

Lu, Dongbin; Ouyang, Minggao

2014-03-01

The existing research of the acceleration control mainly focuses on an optimization of the velocity trajectory with respect to a criterion formulation that weights acceleration time and fuel consumption. The minimum-fuel acceleration problem in conventional vehicle has been solved by Pontryagin's maximum principle and dynamic programming algorithm, respectively. The acceleration control with minimum energy consumption for battery electric vehicle(EV) has not been reported. In this paper, the permanent magnet synchronous motor(PMSM) is controlled by the field oriented control(FOC) method and the electric drive system for the EV(including the PMSM, the inverter and the battery) is modeled to favor over a detailed consumption map. The analytical algorithm is proposed to analyze the optimal acceleration control and the optimal torque versus speed curve in the acceleration process is obtained. Considering the acceleration time, a penalty function is introduced to realize a fast vehicle speed tracking. The optimal acceleration control is also addressed with dynamic programming(DP). This method can solve the optimal acceleration problem with precise time constraint, but it consumes a large amount of computation time. The EV used in simulation and experiment is a four-wheel hub motor drive electric vehicle. The simulation and experimental results show that the required battery energy has little difference between the acceleration control solved by analytical algorithm and that solved by DP, and is greatly reduced comparing with the constant pedal opening acceleration. The proposed analytical and DP algorithms can minimize the energy consumption in EV's acceleration process and the analytical algorithm is easy to be implemented in real-time control.

In vivo leukocyte-mediated brain microcirculatory inflammation: a comparison of osmotherapies and progesterone in severe traumatic brain injury

PubMed Central

Kumasaka, Kenichiro; Marks, Joshua A.; Eisenstadt, Rachel; Murcy, Mohammad A.; Samadi, Davoud; Li, Shengjie; Johnson, Victoria; Browne, Kevin D.; Smith, Douglas H.; Schwab, C. William; Pascual, Jose L.

2017-01-01

BACKGROUND Mannitol, hypertonic saline, and progesterone may blunt leukocyte recruitment after traumatic brain injury (TBI). We hypothesized that progesterone reduces pericontusional recruitment of leukocytes to a greater extent than either osmotherapy a day after TBI. METHODS CD1 mice underwent controlled cortical impact and were treated with osmotherapy (mannitol and hypertonic saline) or progesterone. Thirty-two hours after TBI, live pial microscopy was used to evaluate leukocyte–endothelial interactions and immunohistochemistry was used for the detection of pericontusional tissue polymorphonuclear neutrophils. Neurologic recovery was assessed before sacrifice. RESULTS Mannitol resulted in the lowest in vivo leukocyte recruitment compared with progesterone (795 ± 282 vs 1,636 ± 434 LEU/100 μm/minutes, P < .05). Mannitol also displayed lower tissue accumulation of leukocytes as compared with progesterone (5.7 ± 1.7 vs 15.2 ± .1 LEU/mm2, P = .03). However, progesterone resulted in better neurologic recovery than either osmotherapy. CONCLUSIONS Leukocyte recruitment to injured brain is lowest with mannitol administration. How different agents alter progression of secondary brain injury will require further evaluation in humans. PMID:25305798

Random vibration analysis of train-bridge under track irregularities and traveling seismic waves using train-slab track-bridge interaction model

NASA Astrophysics Data System (ADS)

Zeng, Zhi-Ping; Zhao, Yan-Gang; Xu, Wen-Tao; Yu, Zhi-Wu; Chen, Ling-Kun; Lou, Ping

2015-04-01

The frequent use of bridges in high-speed railway lines greatly increases the probability that trains are running on bridges when earthquakes occur. This paper investigates the random vibrations of a high-speed train traversing a slab track on a continuous girder bridge subjected to track irregularities and traveling seismic waves by the pseudo-excitation method (PEM). To derive the equations of motion of the train-slab track-bridge interaction system, the multibody dynamics and finite element method models are used for the train and the track and bridge, respectively. By assuming track irregularities to be fully coherent random excitations with time lags between different wheels and seismic accelerations to be uniformly modulated, non-stationary random excitations with time lags between different foundations, the random load vectors of the equations of motion are transformed into a series of deterministic pseudo-excitations based on PEM and the wheel-rail contact relationship. A computer code is developed to obtain the time-dependent random responses of the entire system. As a case study, the random vibration characteristics of an ICE-3 high-speed train traversing a seven-span continuous girder bridge simultaneously excited by track irregularities and traveling seismic waves are analyzed. The influence of train speed and seismic wave propagation velocity on the random vibration characteristics of the bridge and train are discussed.

The method of selection of leukocytes in images of preparations of peripheral blood and bone marrow

NASA Astrophysics Data System (ADS)

Zakharenko, Y. V.; Nikitaev, V. G.; Polyakov, E. V.; Seldyukov, S. O.

2017-01-01

Study of the segmentation method on the basis of histogram analysis for the selection of leukocytes in the images of blood and bone marrow in the diagnosis of acute leukemia was conducted in this paper. Method of filtering was offered to eliminate the artifacts, resulting from the selection of leukocytes.

Morphometrical and Morphological Alterations of Human Leukocytes Exposed to 1.8 GHz Electromagnetic Radiations: In Vitro Protective Effects Induced by Polyphenols.

PubMed

Biagi, Pier Francesco; Boffola, Sara; Stefanelli, Riccardo; Schiavulli, Luigi; Ligonzo, Teresa; Casamassima, Giuseppe; Pappagallo, Maria Teresa; Kawaguchi, Kiichiro; Takimoto, Hiroaki; Kumazawa, Yoshio; Fontana, Sergio; Laforgia, Flavia; Russo, Matteo Antonio; Magrone, Thea; Jirillo, Emilio

2016-01-01

Our recent findings have demonstrated that electromagnetic radiations (EMR) (1.8 GHz radiofrequency) are able to in vitro induce morphometrical and morphological modifications of human leukocytes from normal donors. In view of the evidence that polyphenols exert many beneficial effects on plants, animals and humans, leukocytes from human peripheral blood were pre-treated for 1 h with two polyphenol preparations from red grape before EMR exposure (1.8 GHz). Our data will show that polyphenol pre-treatment reverts to normality the morphology of irradiated leukocytes in comparison to irradiated cells only. Conversely, leukocyte morphometry seems to be not affected by this treatment. Here, we demonstrate that polyphenols are also able to normalize leukocyte morphology per se altered before as well as after irradiation. Finally, a working hypothesis aimed at clarifying the protective mechanisms exerted by polyphenols on irradiated leukocytes will be illustrated. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The Fast Track: Facility for Accelerated Service Testing - Transportation Test Center, Pueblo, Colorado, 2nd edition

DOT National Transportation Integrated Search

1978-07-01

This brochure describes the 22 test sections of the Federal Railroad Administration's FAST Track and the various track and mechanical measurements being made as of September 1977 - the end of the first year of operation at the facility. Because of th...

Cannabinoid Receptor 2 Suppresses Leukocyte Inflammatory Migration by Modulating the JNK/c-Jun/Alox5 Pathway*

PubMed Central

Liu, Yi-Jie; Fan, Hong-Bo; Jin, Yi; Ren, Chun-Guang; Jia, Xiao-E; Wang, Lei; Chen, Yi; Dong, Mei; Zhu, Kang-Yong; Dong, Zhi-Wei; Ye, Bai-Xin; Zhong, Zhong; Deng, Min; Liu, Ting Xi; Ren, Ruibao

2013-01-01

Inflammatory migration of immune cells is involved in many human diseases. Identification of molecular pathways and modulators controlling inflammatory migration could lead to therapeutic strategies for treating human inflammation-associated diseases. The role of cannabinoid receptor type 2 (Cnr2) in regulating immune function had been widely investigated, but the mechanism is not fully understood. Through a chemical genetic screen using a zebrafish model for leukocyte migration, we found that both an agonist of the Cnr2 and inhibitor of the 5-lipoxygenase (Alox5, encoded by alox5) inhibit leukocyte migration in response to acute injury. These agents have a similar effect on migration of human myeloid cells. Consistent with these results, we found that inactivation of Cnr2 by zinc finger nuclease-mediated mutagenesis enhances leukocyte migration, while inactivation of Alox5 blocks leukocyte migration. Further investigation indicates that there is a signaling link between Cnr2 and Alox5 and that alox5 is a target of c-Jun. Cnr2 activation down-regulates alox5 expression by suppressing the JNK/c-Jun activation. These studies demonstrate that Cnr2, JNK, and Alox5 constitute a pathway regulating leukocyte migration. The cooperative effect between the Cnr2 agonist and Alox5 inhibitor also provides a potential therapeutic strategy for treating human inflammation-associated diseases. PMID:23539630

Contributions of phosphatidylserine-positive platelets and leukocytes and microparticles to hypercoagulable state in gastric cancer patients.

PubMed

Yang, Chunfa; Ma, Ruishuang; Jiang, Tao; Cao, Muhua; Zhao, Liangliang; Bi, Yayan; Kou, Junjie; Shi, Jialan; Zou, Xiaoming

2016-06-01

Hypercoagulability in gastric cancer is a common complication and a major contributor to poor prognosis. This study aimed to determine procoagulant activity of blood cells and microparticles (MPs) in gastric cancer patients. Phosphatidylserine-positive blood cells and MPs, and their procoagulant properties in particular, were assessed in 48 gastric cancer patients and 35 healthy controls. Phosphatidylserine-positive platelets, leukocytes, and MPs in patients with tumor-node-metastasis stage III/IV gastric cancer were significantly higher than those in stage I/II patients or healthy controls. Moreover, procoagulant activity of platelets, leukocytes, and MPs in stage III/IV patients was significantly increased compared to the controls, as indicated by shorter clotting time, higher intrinsic and extrinsic factor tenase, and prothrombinase complex activity. Interestingly, lactadherin, which competes with factors V and VIII to bind phosphatidylserine, dramatically prolonged clotting time of the cells and MPs by inhibiting factor tenase and prothrombinase complex activity. Although anti-tissue factor antibody significantly attenuated extrinsic tenase complex activity of leukocytes and MPs, it only slightly prolonged clotting times. Meanwhile, treatment with radical resection reduced phosphatidylserine-positive platelets, leukocytes, and MPs, and prolonged the clotting times of the remaining cells and MPs. Our results suggest that phosphatidylserine-positive platelets, leukocytes, and MPs contribute to hypercoagulability and represent a potential therapeutic target to prevent coagulation in patients with stage III/IV gastric cancer.

Position-Specific Acceleration and Deceleration Profiles in Elite Youth and Senior Soccer Players.

PubMed

Vigh-Larsen, Jeppe F; Dalgas, Ulrik; Andersen, Thomas B

2018-04-01

Vigh-Larsen, JF, Dalgas, U, and Andersen, TB. Position-specific acceleration and deceleration profiles in elite youth and senior soccer players. J Strength Cond Res 32(4): 1114-1122, 2018-The purpose of the study was to characterize and compare the position-specific activity profiles of young and senior elite soccer players with special emphasis put on accelerations and decelerations. Eight professional senior matches were tracked using the ZXY tracking system and analyzed for the number of accelerations and decelerations and running distances within different speed zones. Likewise, 4 U19 and 5 U17 matches were analyzed for comparison between youth and senior players. In senior players, the total distance (TD) was 10,776 ± 107 m with 668 ± 28 and 143 ± 10 m being high-intensity running (HIR) and sprinting, respectively. Number of accelerations and decelerations were 81 ± 2 and 84 ± 3, respectively, with central defenders performing the lowest and wide players the highest number. Declines were found between first and second halves for accelerations and decelerations (11 ± 3%), HIR (6 ± 4%), and TD (5 ± 1%), whereas sprinting distance did not differ. U19 players performed a higher number of accelerations, decelerations, and TD compared with senior players. In conclusion, differences in the number and distribution of accelerations and decelerations appeared between player positions, which is of importance when monitoring training and match loads and when prescribing specific training exercises. Furthermore, youth players performed as much high-intensity activities as senior players, indicating that this is not a discriminating physiological parameter between these players.

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.

Vibro-acoustic performance of newly designed tram track structures

NASA Astrophysics Data System (ADS)

Haladin, Ivo; Lakušić, Stjepan; Ahac, Maja

2017-09-01

Rail vehicles in interaction with a railway structure induce vibrations that are propagating to surrounding structures and cause noise disturbance in the surrounding areas. Since tram tracks in urban areas often share the running surface with road vehicles one of top priorities is to achieve low maintenance and long lasting structure. Research conducted in scope of this paper gives an overview of newly designed tram track structures designated for use on Zagreb tram network and their performance in terms of noise and vibration mitigation. Research has been conducted on a 150 m long test section consisted of three tram track types: standard tram track structure commonly used on tram lines in Zagreb, optimized tram structure for better noise and vibration mitigation and a slab track with double sleepers embedded in a concrete slab, which presents an entirely new approach of tram track construction in Zagreb. Track has been instrumented with acceleration sensors, strain gauges and revision shafts for inspection. Relative deformations give an insight into track structure dynamic load distribution through the exploitation period. Further the paper describes vibro-acoustic measurements conducted at the test site. To evaluate the track performance from the vibro-acoustical standpoint, detailed analysis of track decay rate has been analysed. Opposed to measurement technique using impact hammer for track decay rate measurements, newly developed measuring technique using vehicle pass by vibrations as a source of excitation has been proposed and analysed. Paper gives overview of the method, it’s benefits compared to standard method of track decay rate measurements and method evaluation based on noise measurements of the vehicle pass by.

Intracellular lipid dysregulation interferes with leukocyte function in the ovaries of meat-type hens under unrestricted feed intake.

PubMed

Liu, Zu-Chen; Su, Chia-Ming; Xie, Yi-Lun; Chang, Chai-Ju; Chen, Jiang-Young; Wu, Shu-Wei; Chen, Yu-Hui; Walzem, Rosemary L; Huang, San-Yuan; Chen, Shuen-Ei

2016-04-01

Meat-type Red-feather country hens fed ad libitum (AD-hens) exhibit obesity-associated morbidities and a number of ovarian irregularities. Leukocyte participations in ovarian activities are unstudied in AD-hens. In contrast to feed-restricted hens (R-hens), ovulatory process of the F1 follicle appeared delayed in AD-hens in association with reduced F1 follicle progesterone content, gelatinase A (MMP-2) and collagenase-3 (MMP-13) activities coincident with elevated IL-1β and no production (P<0.05), and increased leukocyte infiltration of inflamed necrotic follicle walls. Extracts of AD-hen F1 follicle walls induced greater leukocyte migration than extracts from F1 follicle wall extracts of R-hens (P<0.05). Co-cultures of granulosa cells with increasing numbers of leukocytes from either AD-hens or R-hens exhibited dose dependent reductions in progesterone production and increases in cell death. AD-hen leukocytes were less proapoptotic than their R counterparts (P<0.05). Granulosa MMP-13 and MMP-2 activities were also suppressed in the co-cultures with heterophils or monocytes in a dose-dependent manner (P<0.05). AD heterophils and R monocytes had a greater inhibitory effect on MMP activities in the co-cultures than their respective counterparts (P<0.05). Both basal and LPS-induced IL-1β secretion and MMP-22 or MMP-2 activities in freshly isolated AD-hen leukocytes were reduced (P<0.05). Exposure of AD or R leukocytes to 0.5mM palmitate impaired IL-1β secretion and MMP-22 or MMP-2 activity. Inhibition of ceramide synthesis with FB1 and ROS production with n-MPG scavenging rescued MMP activity and IL-1β production in palmitate treated heterophils, but exacerbated monocyte suppression. These latter findings suggest that intracellular lipid dysregulation in leukocytes contributes to ovarian dysfunction in AD-hens. Copyright © 2016 Elsevier B.V. All rights reserved.

Study on radiation production in the charge stripping section of the RISP linear accelerator

NASA Astrophysics Data System (ADS)

Oh, Joo-Hee; Oranj, Leila Mokhtari; Lee, Hee-Seock; Ko, Seung-Kook

2015-02-01

The linear accelerator of the Rare Isotope Science Project (RISP) accelerates 200 MeV/nucleon 238U ions in a multi-charge states. Many kinds of radiations are generated while the primary beam is transported along the beam line. The stripping process using thin carbon foil leads to complicated radiation environments at the 90-degree bending section. The charge distribution of 238U ions after the carbon charge stripper was calculated by using the LISE++ program. The estimates of the radiation environments were carried out by using the well-proved Monte Carlo codes PHITS and FLUKA. The tracks of 238U ions in various charge states were identified using the magnetic field subroutine of the PHITS code. The dose distribution caused by U beam losses for those tracks was obtained over the accelerator tunnel. A modified calculation was applied for tracking the multi-charged U beams because the fundamental idea of PHITS and FLUKA was to transport fully-ionized ion beam. In this study, the beam loss pattern after a stripping section was observed, and the radiation production by heavy ions was studied. Finally, the performance of the PHITS and the FLUKA codes was validated for estimating the radiation production at the stripping section by applying a modified method.

[THE FEATURES OF PHARMACOKINETICS ANTIBIOTIC CEFTRIAXONE WITH INTRAVENOUS WAY THAT ARE DEPOSITED IN AUTOLOGOUS ERYTHROCYTES AND LEUKOCYTES OF RABBIT].

PubMed

Yussifov, Z; Lokhvitskii, S; Gulyaev, A

2016-11-01

In the experiment on 18 rabbits Сeftriaxone pharmacokinetics after intravenous injection of the medication deposited in autologous erythrocytes and leukocytes were studied. The features of the pharmacokinetics when administered Сeftriaxone in erythrocytes ghost and leukocytes as compared to traditional intravenous drug administration have been determined.It is discussed the possibility of antibiotics transport in the surgical site of infection via cellular carriers in the article. We do the comparative analysis of the main pharmacokinetic parameters of Ceftriaxone in experimental conditions of leukocyte, erythrocyte transport and intravenous way. Based on these results the authors come to the conclusion about the benefits of leukocyte antibiotic transport to the site of surgical infection.

TEMPORAL CHANGES IN PH WITHIN THE PHAGOCYTIC VACUOLE OF THE POLYMORPHONUCLEAR NEUTROPHILIC LEUKOCYTE

PubMed Central

Jensen, Michael S.; Bainton, Dorothy F.

1973-01-01

Although previous workers have established that the pH of the phagocytic vacuole of the polymorphonuclear (PMN) leukocyte changes from neutral to acid, the time course of conversion has not been investigated. The present experiments were initiated to study pH changes immediately after phagocytosis. Peritoneal exudates were induced in rats; 4 h later, yeast stained with pH indicators was injected intraperitoneally, and the exudate was retrieved at 30-s intervals and examined by light microscopy. Results revealed that (a) within 3 min, pH dropped to ∼6.5, as indicated by the change in color of neutral red-stained yeast; (b) within 7–15 min, pH dropped progressively to ∼4.0, as indicated by color change in bromcresol green-stained yeast; (c) pH did not fall below 4, since no color change was observed up to 24 h when bromphenol blue-stained yeast was used. The finding that intravacuolar acidity increases rapidly after phagocytosis is undoubtedly important with respect to PMN leukocyte function in killing and digesting microorganisms, for many PMN leukocyte granule enzymes (i.e., peroxidase and lysosomal enzymes) are activated at acid pH (∼4.5). It follows that temporal changes in pH and maximal pH depression should be considered in studies of intraleukocytic microbicidal mechanisms, since a defect in these factors could result in impaired PMN leukocyte function. PMID:4118890

Leukocyte- and endothelial-derived microparticles: a circulating source for fibrinolysis

PubMed Central

Lacroix, Romaric; Plawinski, Laurent; Robert, Stéphane; Doeuvre, Loïc; Sabatier, Florence; Martinez de Lizarrondo, Sara; Mezzapesa, Anna; Anfosso, Francine; Leroyer, Aurelie S.; Poullin, Pascale; Jourde, Noémie; Njock, Makon-Sébastien; Boulanger, Chantal M.; Anglés-Cano, Eduardo; Dignat-George, Françoise

2012-01-01

Background We recently assigned a new fibrinolytic function to cell-derived microparticles in vitro. In this study we explored the relevance of this novel property of microparticles to the in vivo situation. Design and Methods Circulating microparticles were isolated from the plasma of patients with thrombotic thrombocytopenic purpura or cardiovascular disease and from healthy subjects. Microparticles were also obtained from purified human blood cell subpopulations. The plasminogen activators on microparticles were identified by flow cytometry and enzyme-linked immunosorbent assays; their capacity to generate plasmin was quantified with a chromogenic assay and their fibrinolytic activity was determined by zymography. Results Circulating microparticles isolated from patients generate a range of plasmin activity at their surface. This property was related to a variable content of urokinase-type plasminogen activator and/or tissue plasminogen activator. Using distinct microparticle subpopulations, we demonstrated that plasmin is generated on endothelial and leukocyte microparticles, but not on microparticles of platelet or erythrocyte origin. Leukocyte-derived microparticles bear urokinase-type plasminogen activator and its receptor whereas endothelial microparticles carry tissue plasminogen activator and tissue plasminogen activator/inhibitor complexes. Conclusions Endothelial and leukocyte microparticles, bearing respectively tissue plasminogen activator or urokinase-type plasminogen activator, support a part of the fibrinolytic activity in the circulation which is modulated in pathological settings. Awareness of this blood-borne fibrinolytic activity conveyed by microparticles provides a more comprehensive view of the role of microparticles in the hemostatic equilibrium. PMID:22733025

Genotoxic potential of TiO2 on bottlenose dolphin leukocytes.

PubMed

Bernardeschi, Margherita; Guidi, Patrizia; Scarcelli, Vittoria; Frenzilli, Giada; Nigro, Marco

2010-01-01

Titanium dioxide is extensively used in a variety of products, including industrial materials and cosmetics. Studies mainly performed on human cell lines and in vivo exposure on experimental animals have raised concern about the toxic effects of ultrafine titanium dioxide; however, scarce information is available about its impact on aquatic life. The aim of this article was to assess the genotoxic potential of TiO(2) (anatase and rutile) on bottlenose dolphin leukocytes. Blood samples were obtained from four male and one female specimens reared at the Adriatic SeaWorld "Oltremare" (Riccione, Italy). Leukocytes were isolated by the lyses procedure and in vitro exposed to TiO(2) in RPMI. Experimental solutions were sonicated immediately before dosing the cells. Three exposure times (4, 24 and 48 h) and three doses (20, 50 and 100 microg/ml) were tested. Genotoxicity was detected by the single-cell gel electrophoresis (or comet assay) at pH > or = 13, assessing single/double-strand breaks and alkali-labile sites. Cytotoxicity was also detected by the Trypan blue exclusion method. Results showed that both the crystalline forms of TiO(2) were genotoxic for bottlenose dolphin leukocytes, with a statistically significant increase of DNA fragmentation after exposure to 50 and 100 microg/ml for 24 and 48 h. Although preliminary, these are the first data regarding the genetic susceptibility of toothed cetaceans toward an "emerging" pollutant, such as TiO(2) particles.

Leukocyte glutamate dehydrogenase activity in patients with degenerative neurological disorders.

PubMed Central

Aubby, D; Saggu, H K; Jenner, P; Quinn, N P; Harding, A E; Marsden, C D

1988-01-01

Leukocyte glutamate dehydrogenase (GDH) activity was measured in 39 normal subjects, 32 neurological controls, 66 patients with progressive ataxic disorders, 32 with multiple system atrophy, 40 with Parkinson's disease, eight with Steele-Richardson-Olszewski syndrome, eight with juvenile Parkinsonism and four with the dystonia-Parkinsonism syndrome. GDH activity was reproducible to within 10% in leukocyte pellets stored at -70 degrees C for up to 9 months, and did not vary with sex or age in control subjects. There was marked variation in the relative proportions of heat stable and heat labile forms of GDH between control subjects and on repeated assay in the same subject. Total leukocyte GDH activity was similar in normal subjects and neurological controls. Mean total GDH activity was reduced in all patient groups by between 15 to 29% compared with controls. Fourteen patients had total GDH activity below 50% of the control mean, but low values were not specific for any one disease (five had ataxic disorders, four Parkinson's disease, three multiple system atrophy, one juvenile Parkinsonism, and one dystonia-Parkinsonism). The heat labile fraction of GDH represented about 20% of total activity in control subjects, and 27% in the patients with reduced total GDH activity. Thus low GDH activity was not disease-specific in this study, and the heat-labile GDH fraction was not selectively affected. "Reduced" leucocyte GDH activity in some patients may represent no more than the lower end of a normal distribution. PMID:3204397

Mitochondrial DNA levels in Huntington disease leukocytes and dermal fibroblasts.

PubMed

Jędrak, Paulina; Krygier, Magdalena; Tońska, Katarzyna; Drozd, Małgorzata; Kaliszewska, Magdalena; Bartnik, Ewa; Sołtan, Witold; Sitek, Emilia J; Stanisławska-Sachadyn, Anna; Limon, Janusz; Sławek, Jarosław; Węgrzyn, Grzegorz; Barańska, Sylwia

2017-08-01

Huntington disease (HD) is an inherited neurodegenerative disorder caused by mutations in the huntingtin gene. Involvement of mitochondrial dysfunctions in, and especially influence of the level of mitochondrial DNA (mtDNA) on, development of this disease is unclear. Here, samples of blood from 84 HD patients and 79 controls, and dermal fibroblasts from 10 HD patients and 9 controls were analysed for mtDNA levels. Although the type of mitochondrial haplogroup had no influence on the mtDNA level, and there was no correlation between mtDNA level in leukocytes in HD patients and various parameters of HD severity, some considerable differences between HD patients and controls were identified. The average mtDNA/nDNA relative copy number was significantly higher in leukocytes, but lower in fibroblasts, of symptomatic HD patients relative to the control group. Moreover, HD women displayed higher mtDNA levels in leukocytes than HD men. Because this is the largest population analysed to date, these results might contribute to explanation of discrepancies between previously published studies concerning levels of mtDNA in cells of HD patients. We suggest that the size of the investigated population and type of cells from which DNA is isolated could significantly affect results of mtDNA copy number estimation in HD. Hence, these parameters should be taken into consideration in studies on mtDNA in HD, and perhaps also in other diseases where mitochondrial dysfunction occurs.

Efficacy of leukocyte- and platelet-rich fibrin in wound healing: a randomized controlled clinical trial.

PubMed

Chignon-Sicard, Bérengère; Georgiou, Charalambos A; Fontas, Eric; David, Sylvain; Dumas, Pierre; Ihrai, Tarik; Lebreton, Elisabeth

2012-12-01

Application of platelet concentrates to wounds could speed healing. Leukocyte- and platelet-rich fibrin, a relatively recent development, stands out from the other preparations. This prospective, randomized, controlled clinical trial studied the rate of healing of postoperative hand wounds after a single application of leukocyte- and platelet-rich fibrin. Eligible patients were healthy individuals older than 18 years who had been scheduled for elective McCash (open palm) surgery for Dupuytren disease at the Plastic and Hand Surgery Department of Nice's University Hospital between August of 2007 and February of 2010. The control group received the reference care of petroleum jelly mesh (Vaselitulle), and test patients had leukocyte- and platelet-rich fibrin applied. The primary endpoint was healing delay measured in postoperative days. Secondary endpoints included pain, bleeding, and wound exudate. The trial was carried out as a single-blind trial. Among the 68 randomized patients, 33 patients in the leukocyte- and platelet-rich fibrin group and 31 in the Vaselitulle group were analyzed. Primary endpoint analysis showed a median healing delay of 24 days (interquartile range, 18 to 28 days) for the fibrin group and 29 days (interquartile range, 26 to 35 days) for the Vaselitulle group (p = 0.014, log-rank test). Postoperative pain assessment, bleeding, and exudate were always lower for the fibrin group, but not significantly so. The authors trial demonstrates that a single leukocyte- and platelet-rich fibrin application on fresh postoperative hand wounds shows a median improvement of 5 days in comparison with the standard treatment. Therapeutic, II.

With medium-chain triglycerides, higher and faster oxygen radical production by stimulated polymorphonuclear leukocytes occurs.

PubMed

Kruimel, J W; Naber, A H; Curfs, J H; Wenker, M A; Jansen, J B

2000-01-01

Parenteral lipid emulsions are suspected of suppressing the immune function. However, study results are contradictory and mainly concern the conventional long-chain triglyceride emulsions. Polymorphonuclear leukocytes were preincubated with parenteral lipid emulsions. The influence of the lipid emulsions on the production of oxygen radicals by these stimulated leukocytes was studied by measuring chemiluminescence. Three different parenteral lipid emulsions were tested: long-chain triglycerides, a physical mixture of medium- and long-chain triglycerides, and structured triglycerides. Structured triglycerides consist of triglycerides where the medium- and long-chain fatty acids are attached to the same glycerol molecule. Stimulated polymorphonuclear leukocytes preincubated with the physical mixture of medium- and long-chain triglycerides showed higher levels of oxygen radicals (p < .005) and faster production of oxygen radicals (p < .005) compared with polymorphonuclear leukocytes preincubated with long-chain triglycerides or structured triglycerides. Additional studies indicated that differences in results of various lipid emulsions were not caused by differences in emulsifier. The overall production of oxygen radicals was significantly lower after preincubation with the three lipid emulsions compared with controls without lipid emulsion. A physical mixture of medium- and long-chain triglycerides induced faster production of oxygen radicals, resulting in higher levels of oxygen radicals, compared with long-chain triglycerides or structured triglycerides. This can be detrimental in cases where oxygen radicals play either a pathogenic role or a beneficial one, such as when rapid phagocytosis and killing of bacteria is needed. The observed lower production of oxygen radicals by polymorphonuclear leukocytes in the presence of parenteral lipid emulsions may result in immunosuppression by these lipids.

Directional Track Selection Technique in CR39 SSNTD for lowyield reaction experiments

NASA Astrophysics Data System (ADS)

Ingenito, Francesco; Andreoli, Pierluigi; Batani, Dimitri; Bonasera, Aldo; Boutoux, Guillaume; Burgy, Frederic; Cipriani, Mattia; Consoli, Fabrizio; Cristofari, Giuseppe; De Angelis, Riccardo; Di Giorgio, Giorgio; Ducret, Jean Eric; Giulietti, Danilo; Jakubowska, Katarzyna

2018-01-01

There is a great interest in the study of p-11B aneutronic nuclear fusion reactions, both for energy production and for determination of fusion cross-sections at low energies. In this context we performed experiments at CELIA in which energetic protons, accelerated by the laser ECLIPSE, were directed toward a solid Boron target. Because of the small cross-sections at these energies the number of expected reactions is low. CR39 Solid-State Nuclear Track Detectors (SSNTD) were used to detect the alpha particles produced. Because of the low expected yield, it is difficult to discriminate the tracks due to true fusion products from those due to natural background in the CR39. To this purpose we developed a methodology of particle recognition according to their direction with respect to the detector normal, able to determine the position of their source. We applied this to the specific experiment geometry, so to select from all the tracks those due to particles coming from the region of interaction between accelerated protons and solid boron target. This technique can be of great help on the analysis of SSNTD in experiments with low yield reactions, but can be also generally applied to any experiment where particles reach the track detector with known directions, and for example to improve the detection limit of particle spectrometers using CR39.

Effects of granulocyte colony stimulating factor on retinal leukocyte and erythrocyte flux in the human retina.

PubMed

Fuchsjäger-Mayrl, Gabriele; Malec, Magdalena; Polska, Elzbieta; Jilma, Bernd; Wolzt, Michael; Schmetterer, Leopold

2002-05-01

The blue-field entoptic technique was introduced more than 20 years ago to quantify perimacular white blood cell flux. However, a final confirmation that the perceived corpuscles represent leukocytes is still unavailable. The study design was randomized, placebo-controlled, and double masked with two parallel groups. Fifteen healthy male subjects received a single dose of granulocyte colony stimulating factor (G-CSF, 300 microg) and 15 other subjects received placebo. The following parameters were assessed at baseline and at 12 minutes and 8 hours after administration: retinal white blood cell flux, with the blue-field entoptic technique; retinal blood velocities, with bidirectional laser Doppler velocimetry; retinal venous diameter determined with a retinal vessel analyzer; and blood pressure and pulse rate determined by automated oscillometry and pulse oxymetry, respectively. After 12 minutes, G-CSF reduced total leukocyte count from 5.5 +/- 1.4 10(9)/L at baseline to 1.9 +/- 0.4 10(9)/L. This was paralleled by a 35% +/- 11% decrease in retinal white blood cell density. After 8 hours G-CSF increased total leukocyte counts to 20.0 +/- 4.4 10(9)/L. Again, this increase in circulating leukocytes was reflected by an increase in retinal white blood cell density (110% +/- 48%). All effects were significant at P < 0.001. By contrast, none of the other hemodynamic parameters was changed by administration of G-CSF. The results clearly indicate that the blue-field entoptic technique assesses leukocyte movement in the perimacular capillaries of the retina. Moreover, white blood cell density appears to adequately reflect the number of circulating leukocytes within the retinal microvasculature. Hence, an increase in retinal white blood cell density does not necessarily reflect retinal vasodilatation.

Acceleration of recovery in acute renal failure: from cellular mechanisms of tubular repair to innovative targeted therapies.

PubMed

Abbate, M; Remuzzi, G

1996-05-01

Kidney repair from injury is a major focus of interest for research, both clinical and basic, in the field of acute renal failure. This is so because very little progress has been made during the past several years to improve mortality in hospitalized patients with acute renal failure despite the unique potential of the kidney for complete structural and functional recovery. Novel therapeutic options have recently emerged from the knowledge of molecular mechanisms of tissue injury after ischemia, including pathways of endothelial-leukocyte interaction and epithelial cell aggregation mediated by integrin molecules. These strategies are promising because they may target early mechanisms of leukocyte infiltration and tubular obstruction. However, it seems clear that additional interventions should address the reparative program that potentially leads to the full restoration of kidney structure and function. Thus, acceleration of repair from acute renal failure is achieved experimentally by growth factors which besides different renal actions seem to have in common the ability to stimulate proliferation of surviving tubular epithelial cells. We direct attention to cellular processes which characterize, and possibly have role in, renal repair from acute tubular injury as potential targets of therapy. In addition to proliferation, they include epithelial differentiation and apoptosis. Further investigation in the biology of repair should set the stage for rational design of targeted therapies which may accelerate the pace of recovery and hopefully decrease mortality in such a dramatic and potentially reversible setting.

Leukocyte Telomere Length in the Finnish Diabetes Prevention Study

PubMed Central

Hovatta, Iiris; de Mello, Vanessa D. F.; Kananen, Laura; Lindström, Jaana; Eriksson, Johan G.; Ilanne-Parikka, Pirjo; Keinänen-Kiukaanniemi, Sirkka; Peltonen, Markku; Tuomilehto, Jaakko; Uusitupa, Matti

2012-01-01

Leukocyte telomere length (TL) is considered a biomarker for biological aging. Shortened TL has been observed in many complex diseases, including type 2 diabetes (T2DM). Lifestyle intervention studies, e.g. the Diabetes Prevention Study (DPS), have shown a decrease in the incidence of T2DM by promoting healthy lifestyles in individuals with impaired glucose tolerance (IGT). Our aim was to study in the DPS the influence of the lifestyle intervention on TL. TL was measured by quantitative PCR-based method at two time points (N = 334 and 343) on average 4.5 years apart during the active intervention and post-intervention follow-up. TL inversely correlated with age. Our main finding was that TL increased in about two thirds of the individuals both in the intervention and in the control groups during follow-up; TL increased most in individuals with the shortest TL at the first measurement. TL was not associated with development of T2DM, nor did lifestyle intervention have an effect on TL. No association between insulin secretion or insulin resistance indices and TL was observed. We did not detect an association between TL and development of T2DM in the DPS participants. It could be due to all participants being overweight and having IGT at baseline, both of which have been found to be independently associated with shorter leukocyte TL in some earlier studies. TL had no substantial role in worsening of glucose tolerance in people with IGT. Our study confirms that leukocyte TL can increase with time even in obese people with impaired glucose metabolism. PMID:22493726

Association between Kinin B1 Receptor Expression and Leukocyte Trafficking across Mouse Mesenteric Postcapillary Venules

PubMed Central

McLean, Peter G.; Ahluwalia, Amrita; Perretti, Mauro

2000-01-01

Using intravital microscopy, we examined the role played by B1 receptors in leukocyte trafficking across mouse mesenteric postcapillary venules in vivo. B1 receptor blockade attenuated interleukin (IL)-1β–induced (5 ng intraperitoneally, 2 h) leukocyte–endothelial cell interactions and leukocyte emigration (∼50% reduction). The B1 receptor agonist des-Arg9bradykinin (DABK), although inactive in saline- or IL-8–treated mice, caused marked neutrophil rolling, adhesion, and emigration 24 h after challenge with IL-1β (when the cellular response to IL-1β had subsided). Reverse transcriptase polymerase chain reaction and Western blot revealed a temporal association between the DABK-induced response and upregulation of mesenteric B1 receptor mRNA and de novo protein expression after IL-1β treatment. DABK-induced leukocyte trafficking was antagonized by the B1 receptor antagonist des-arg10HOE 140 but not by the B2 receptor antagonist HOE 140. Similarly, DABK effects were maintained in B2 receptor knockout mice. The DABK-induced responses involved the release of neuropeptides from C fibers, as capsaicin treatment inhibited the responses. Treatment with the neurokinin (NK)1 and NK3 receptor antagonists attenuated the responses, whereas NK2, calcitonin gene-related peptide, or platelet-activating factor receptor antagonists had no effect. Substance P caused leukocyte recruitment that, similar to DABK, was inhibited by NK1 and NK3 receptor blockade. Mast cell depletion using compound 48/80 reduced DABK-induced leukocyte trafficking, and DABK treatment was shown histologically to induce mast cell degranulation. DABK-induced trafficking was inhibited by histamine H1 receptor blockade. Our findings provide clear evidence that B1 receptors play an important role in the mediation of leukocyte–endothelial cell interactions in postcapillary venules, leading to leukocyte recruitment during an inflammatory response. This involves activation of C fibers and mast cells

HK2 Recruitment to Phospho-BAD Prevents Its Degradation, Promoting Warburg Glycolysis by Theileria-Transformed Leukocytes.

PubMed

Haidar, Malak; Lombès, Anne; Bouillaud, Frédéric; Kennedy, Eileen J; Langsley, Gordon

2017-03-10

Theileria annulata infects bovine leukocytes, transforming them into invasive, cancer-like cells that cause the widespread disease called tropical theileriosis. We report that in Theileria-transformed leukocytes hexokinase-2 (HK2) binds to B cell lymphoma-2-associated death promoter (BAD) only when serine (S) 155 in BAD is phosphorylated. We show that HK2 recruitment to BAD is abolished by a cell-penetrating peptide that acts as a nonphosphorylatable BAD substrate that inhibits endogenous S155 phosphorylation, leading to complex dissociation and ubiquitination and degradation of HK2 by the proteasome. As HK2 is a critical enzyme involved in Warburg glycolysis, its loss forces Theileria-transformed macrophages to switch back to HK1-dependent oxidative glycolysis that down-regulates macrophage proliferation only when they are growing on glucose. When growing on galactose, degradation of HK2 has no effect on Theileria-infected leukocyte proliferation, because metabolism of this sugar is independent of hexokinases. Thus, targeted disruption of the phosphorylation-dependent HK2/BAD complex may represent a novel approach to control Theileria-transformed leukocyte proliferation.

Genetic Analysis of 13 Iranian Families With Leukocyte Adhesion Deficiency Type 1.

PubMed

Teimourian, Shahram; De Boer, Martin; Roos, Dirk; Isaian, Anna; Bemanian, Mohammad Hassan; Lashkary, Sharhzad; Nabavi, Mohammad; Arshi, Saba; Nateghian, Alireza; Sayyahfar, Shirin; Sazgara, Faezeh; Taheripak, Gholamreza; Alipour Fayez, Elham

2018-05-10

Leukocyte adhesion deficiency type 1 is a rare, autosomal recessive disorder that results from mutations in the ITGB2 gene. This gene encodes the CD18 subunit of β2 integrin leukocyte adhesion cell molecules. Leukocyte adhesion deficiency type 1 is characterized by recurrent bacterial infections, impaired wound healing, inadequate pus formation, and delayed separation of the umbilical cord. Blood samples were taken from 13 patients after written consent had been obtained. Genomic DNA was extracted, and ITGB2 exons and exon-intron boundaries were amplified by polymerase chain reaction. The products were examined by Sanger sequencing. In this study, 8 different previously reported mutations (intron7+1G>A, c.715G>A, c.1777 C>T, c.843del C, c.1768T>C, c.1821C>A, Intron7+1G>A, c.1885G>A) and 2 novel mutations (c.1821C>A; p.Tyr607Ter and c.1822C>T; p.Gln608Ter) were found. c.1821C>A (p.Tyr607Ter) and c.1822C>T (p.Gln608Ter) mutations should be included in the panel of carrier detection and prenatal diagnosis.

Functional role of gap junctions in cytokine-induced leukocyte adhesion to endothelium in vivo

PubMed Central

Véliz, Loreto P.; González, Francisco G.; Duling, Brian R.; Sáez, Juan C.; Boric, Mauricio P.

2008-01-01

To assess the hypothesis that gap junctions (GJs) participate on leukocyte-endothelium interactions in the inflammatory response, we compared leukocyte adhesion and transmigration elicited by cytokine stimulation in the presence or absence of GJ blockers in the hamster cheek pouch and also in the cremaster muscle of wild-type (WT) and endothelium-specific connexin 43 (Cx43) null mice (Cx43e−/−). In the cheek pouch, topical tumor necrosis factor-α (TNF-α; 150 ng/ml, 15 min) caused a sustained increment in the number of leukocytes adhered to venular endothelium (LAV) and located at perivenular regions (LPV). Superfusion with the GJ blockers 18-α-glycyrrhetinic acid (AGA; 75 μM) or 18-β-glycyrrhetinic acid (50 μM) abolished the TNF-α-induced increase in LAV and LPV; carbenoxolone (75 μM) or oleamide (100 μM) reduced LAV by 50 and 75%, respectively, and LPV to a lesser extent. None of these GJ blockers modified venular diameter, blood flow, or leukocyte rolling. In contrast, glycyrrhizin (75 μM), a non-GJ blocker analog of AGA, was devoid of effect. Interestingly, when AGA was removed 90 min after TNF-α stimulation, LAV started to rise at a similar rate as in control. Conversely, application of AGA 90 min after TNF-α reduced the number of previously adhered cells. In WT mice, intrascrotal injection of TNF-α (0.5 μg/0.3 ml) increased LAV (fourfold) and LPV (threefold) compared with saline-injected controls. In contrast to the observations in WT animals, TNF-α stimulation did not increase LAV or LPV in Cx43e−/− mice. These results demonstrate an important role for GJ communication in leukocyte adhesion and transmigration during acute inflammation in vivo and further suggest that endothelial Cx43 is key in these processes. PMID:18599597

Metabolic syndrome enhances endoplasmic reticulum, oxidative stress and leukocyte-endothelium interactions in PCOS.

PubMed

Bañuls, Celia; Rovira-Llopis, Susana; Martinez de Marañon, Aranzazu; Veses, Silvia; Jover, Ana; Gomez, Marcelino; Rocha, Milagros; Hernandez-Mijares, Antonio; Victor, Victor M

2017-06-01

Polycystic ovary syndrome (PCOS) is associated with insulin resistance, which can lead to metabolic syndrome (MetS). Oxidative stress and leukocyte-endothelium interactions are related to PCOS. Our aim was to evaluate whether the presence of MetS in PCOS patients can influence endoplasmic reticulum (ER) and oxidative stress and leukocyte-endothelium interactions. This was a prospective controlled study conducted in an academic medical center. The study population consisted of 148 PCOS women (116 without/32 with MetS) and 112 control subjects (87 without / 25 with MetS). Metabolic parameters, reactive oxygen species (ROS) production, ER stress markers (GRP78, sXBP1, ATF6), leukocyte-endothelium interactions, adhesion molecules (VCAM-1, ICAM-1, E-Selectin), TNF-α and IL-6 were determined. Total ROS, inflammatory parameters and adhesion molecules were enhanced in the presence of MetS (p<0.05), and the PCOS+MetS group showed higher levels of IL-6 and ICAM-1 than controls (p<0.05). Increased adhesion and leukocyte rolling flux were observed in PCOS and PCOS+MetS groups vs their respective controls (p<0.05). GRP78 protein expression was higher in the PCOS groups (p<0.05 vs controls) and sXBP1 was associated with the presence of MetS (p<0.05 vs controls without MetS). Furthermore, PCOS+MetS patients exhibited higher GRP78 and ATF6 levels than controls and PCOS patients without MetS (p<0.05). In PCOS women, HOMA-IR was positively correlated with ICAM-1 (r=0.501; p<0.01), ROS (r=0.604; p<0.01), rolling flux (r=0.455;p<0.05) and GRP78 (r=0.574; p<0.001). Our findings support the hypothesis of an association between altered metabolic status, increased ROS production, ER stress and leukocyte-endothelium interactions in PCOS, all of which are related to vascular complications. Copyright © 2017 Elsevier Inc. All rights reserved.

[Clinical effects of the transfusion of leukocytes isolated by filtration from continuous flux].

PubMed

Malinvaud, G; Gailiard, S; Gualde, N

1977-09-01

The present work studies clinical effects of leukocyte transfusions to patients with medular aplasis. Leukocytes were collected by filtration on a continuous flow, according to the technique earlier described in this review [9]. Two major points are stressed on tolerance by the patients of the injected products and clinical efficiency. Seventy eight suspensions were prepared and transfused to 30 patients in the course of 36 incidents of myeloid insufficiency. All patients but two evidenced by the time of transfusion a number of polynuclears inferior to 500 per cubic millimeter. The infection was quite serious with increased gravity despite the antibiotherapy. Intolerance was noticeable in about one third of the cases, half of which consisted only in chillis by the end or after transfusion. Only one accident consisting in acute respiration troubles and shock was observed. This however does not occur by chance. It involves sensitization which may be related to HLA system but may also be of different nature, although not clearly identified. Nevertheless is efficiency of the injected products demonstrated by recirculation of the transfused leukocytes. This was noticed within an hour following transfusion for more than 50 percent of the cases. Furthermore it lasted for 16 hours in more than one fourth of the patients. In addition following results are in favour of real clinical efficiency. Certainly in the course of 16 aplasic incidents, no improvement was observed. For most patients however transfusions were late and not renewed or the patients were highly immunized. Conversely the infection state did improve in 8 patients, the disease responsible for aplasia running its course on its own. Lastly in the course of 12 aplasic incidents, infection and acute aplasia did cure. All these observations should lead one to study with great care the immunological state of the recipient. Instructions being known, the number of transfused leukocytes should be sufficient and

Exercise leukocyte profiles in healthy, type 1 diabetic, overweight, and asthmatic children.

PubMed

Rosa, Jaime S; Schwindt, Christina D; Oliver, Stacy R; Leu, Szu-Yun; Flores, Rebecca L; Galassetti, Pietro R

2009-02-01

Leukocytosis contributes to exercise-induced immune modulation, which is a mechanism of cardiovascular protection. However, this process is poorly defined in children. We therefore measured leukocytes in 45 healthy, 18 overweight, 16 type 1 diabetic, and 8 asthmatic children at pre, end-, and 30-min postexercise (30-min intermittent or 6-min continuous). In all groups, total leukocytes, neutrophils, lymphocytes, and monocytes increased at end-exercise, but returned to baseline by 30-min postexercise, including neutrophils, previously reported to remain elevated for at least some exercise formats. This highly preserved pattern indicates the importance of the adaptive response to physical stress across multiple health conditions.

Symplectic orbit and spin tracking code for all-electric storage rings

NASA Astrophysics Data System (ADS)

Talman, Richard M.; Talman, John D.

2015-07-01

Proposed methods for measuring the electric dipole moment (EDM) of the proton use an intense, polarized proton beam stored in an all-electric storage ring "trap." At the "magic" kinetic energy of 232.792 MeV, proton spins are "frozen," for example always parallel to the instantaneous particle momentum. Energy deviation from the magic value causes in-plane precession of the spin relative to the momentum. Any nonzero EDM value will cause out-of-plane precession—measuring this precession is the basis for the EDM determination. A proposed implementation of this measurement shows that a proton EDM value of 10-29e -cm or greater will produce a statistically significant, measurable precession after multiply repeated runs, assuming small beam depolarization during 1000 s runs, with high enough precision to test models of the early universe developed to account for the present day particle/antiparticle population imbalance. This paper describes an accelerator simulation code, eteapot, a new component of the Unified Accelerator Libraries (ual), to be used for long term tracking of particle orbits and spins in electric bend accelerators, in order to simulate EDM storage ring experiments. Though qualitatively much like magnetic rings, the nonconstant particle velocity in electric rings gives them significantly different properties, especially in weak focusing rings. Like the earlier code teapot (for magnetic ring simulation) this code performs exact tracking in an idealized (approximate) lattice rather than the more conventional approach, which is approximate tracking in a more nearly exact lattice. The Bargmann-Michel-Telegdi (BMT) equation describing the evolution of spin vectors through idealized bend elements is also solved exactly—original to this paper. Furthermore the idealization permits the code to be exactly symplectic (with no artificial "symplectification"). Any residual spurious damping or antidamping is sufficiently small to permit reliable tracking for the

CD Nomenclature 2015: Human Leukocyte Differentiation Antigen Workshops as a Driving Force in Immunology.

PubMed

Engel, Pablo; Boumsell, Laurence; Balderas, Robert; Bensussan, Armand; Gattei, Valter; Horejsi, Vaclav; Jin, Bo-Quan; Malavasi, Fabio; Mortari, Frank; Schwartz-Albiez, Reinhard; Stockinger, Hannes; van Zelm, Menno C; Zola, Heddy; Clark, Georgina

2015-11-15

CD (cluster of differentiation) Ags are cell surface molecules expressed on leukocytes and other cells relevant for the immune system. CD nomenclature has been universally adopted by the scientific community and is officially approved by the International Union of Immunological Societies and sanctioned by the World Health Organization. It provides a unified designation system for mAbs, as well as for the cell surface molecules that they recognize. This nomenclature was established by the Human Leukocyte Differentiation Antigens Workshops. In addition to defining the CD nomenclature, these workshops have been instrumental in identifying and determining the expression and function of cell surface molecules. Over the past 30 y, the data generated by the 10 Human Leukocyte Differentiation Antigens Workshops have led to the characterization and formal designation of more than 400 molecules. CD molecules are commonly used as cell markers, allowing the identification and isolation of leukocyte populations, subsets, and differentiation stages. mAbs against these molecules have proven to be essential for biomedical research and diagnosis, as well as in biotechnology. More recently, they have been recognized as invaluable tools for the treatment of several malignancies and autoimmune diseases. In this article, we describe how the CD nomenclature was established, present the official updated list of CD molecules, and provide a rationale for their usefulness in the 21st century. Copyright © 2015 by The American Association of Immunologists, Inc.

Maternal T-Cell Engraftment Interferes With Human Leukocyte Antigen Typing in Severe Combined Immunodeficiency.

PubMed

Liu, Chang; Duffy, Brian; Bednarski, Jeffrey J; Calhoun, Cecelia; Lay, Lindsay; Rundblad, Barrett; Payton, Jacqueline E; Mohanakumar, Thalachallour

2016-02-01

To report the laboratory investigation of a case of severe combined immunodeficiency (SCID) with maternal T-cell engraftment, focusing on the interference of human leukocyte antigen (HLA) typing by blood chimerism. HLA typing was performed with three different methods, including sequence-specific primer (SSP), sequence-specific oligonucleotide, and Sanger sequencing on peripheral blood leukocytes and buccal cells, from a 3-month-old boy and peripheral blood leukocytes from his parents. Short tandem repeat (STR) testing was performed in parallel. HLA typing of the patient's peripheral blood leukocytes using the SSP method demonstrated three different alleles for each of the HLA-B and HLA-C loci, with both maternal alleles present at each locus. Typing results from the patient's buccal cells showed a normal pattern of inheritance for paternal and maternal haplotypes. STR enrichment testing of the patient's CD3+ T lymphocytes and CD15+ myeloid cells confirmed maternal T-cell engraftment, while the myeloid cell profile matched the patient's buccal cells. Maternal T-cell engraftment may interfere with HLA typing in patients with SCID. Selection of the appropriate typing methods and specimens is critical for accurate HLA typing and immunologic assessment before allogeneic hematopoietic stem cell transplantation. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Fibronectin connecting segment-1 peptide inhibits pathogenic leukocyte trafficking and inflammatory demyelination in experimental models of chronic inflammatory demyelinating polyradiculoneuropathy.

PubMed

Dong, Chaoling; Greathouse, Kelsey M; Beacham, Rebecca L; Palladino, Steven P; Helton, E Scott; Ubogu, Eroboghene E

2017-06-01

The molecular determinants of pathogenic leukocyte migration across the blood-nerve barrier (BNB) in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) are unknown. Specific disease modifying therapies for CIDP are also lacking. Fibronectin connecting segment-1 (FNCS1), an alternatively spliced fibronectin variant expressed by microvascular endothelial cells at sites of inflammation in vitro and in situ, is a counterligand for leukocyte α 4 integrin (also known as CD49d) implicated in pathogenic leukocyte trafficking in multiple sclerosis and inflammatory bowel disease. We sought to determine the role of FNCS1 in CIDP patient leukocyte trafficking across the BNB in vitro and in severe chronic demyelinating neuritis in vivo using a representative spontaneous murine CIDP model. Peripheral blood mononuclear leukocytes from 7 untreated CIDP patients were independently infused into a cytokine-treated, flow-dependent in vitro BNB model system. Time-lapse digital video microscopy was performed to visualize and quantify leukocyte trafficking, comparing FNCS1 peptide blockade to relevant controls. Fifty 24-week old female B7-2 deficient non-obese diabetic mice with spontaneous autoimmune peripheral polyneuropathy (SAPP) were treated daily with 2mg/kg FNCS1 peptide for 5days via intraperitoneal injection with appropriate controls. Neurobehavioral measures of disease severity, motor nerve electrophysiology assessments and histopathological quantification of inflammation and morphometric assessment of demyelination were performed to determine in vivo efficacy. The biological relevance of FNCS1 and CD49d in CIDP was evaluated by immunohistochemical detection in affected patient sural nerve biopsies. 25μM FNCS1 peptide maximally inhibited CIDP leukocyte trafficking at the human BNB in vitro. FNCS1 peptide treatment resulted in significant improvements in disease severity, motor electrophysiological parameters of demyelination and histological measures of

Relationship between interpersonal sensitivity and leukocyte telomere length.

PubMed

Suzuki, Akihito; Matsumoto, Yoshihiko; Enokido, Masanori; Shirata, Toshinori; Goto, Kaoru; Otani, Koichi

2017-10-10

Telomeres are repetitive DNA sequences located at the ends of chromosomes, and telomere length represents a biological marker for cellular aging. Interpersonal sensitivity, excessive sensitivity to the behavior and feelings of others, is one of the vulnerable factors to depression. In the present study, we examined the effect of interpersonal sensitivity on telomere length in healthy subjects. The subjects were 159 unrelated healthy Japanese volunteers. Mean age ± SD (range) of the subjects was 42.3 ± 7.8 (30-61) years. Interpersonal sensitivity was assessed by the Japanese version of the Interpersonal Sensitivity Measure (IPSM). Leukocyte telomere length was determined by a quantitative real-time PCR method. Higher scores of the total IPSM were significantly (β = -0.163, p = 0.038) related to shorter telomere length. In the sub-scale analysis, higher scores of timidity were significantly (β = -0.220, p = 0.044) associated with shorter telomere length. The present study suggests that subjects with higher interpersonal sensitivity have shorter leukocyte telomere length, implying that interpersonal sensitivity has an impact on cellular aging.

First experiences with an accelerated CMV antigenemia test: CMV Brite Turbo assay.

PubMed

Visser, C E; van Zeijl, C J; de Klerk, E P; Schillizi, B M; Beersma, M F; Kroes, A C

2000-06-01

Cytomegalovirus disease is still a major problem in immunocompromised patients, such as bone marrow or kidney transplantation patients. The detection of viral antigen in leukocytes (antigenemia) has proven to be a clinically relevant marker of CMV activity and has found widespread application. Because most existing assays are rather time-consuming and laborious, an accelerated version (Brite Turbo) of an existing method (Brite) has been developed. The major modification is in the direct lysis of erythrocytes instead of separation by sedimentation. In this study the Brite Turbo method has been compared with the conventional Brite method to detect CMV antigen pp65 in peripheral blood leukocytes of 107 consecutive immunocompromised patients. Both tests produced similar results. Discrepancies were limited to the lowest positive range and sensitivity and specificity were comparable for both tests. Two major advantages of the Brite Turbo method could be observed in comparison to the original method: assay-time was reduced by more than 50% and only 2 ml of blood was required. An additional advantage was the higher number of positive nuclei in the Brite Turbo method attributable to the increased number of granulocytes in the assay. Early detection of CMV infection or reactivation has become faster and easier with this modified assay.

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

Leung, Cindy W; Laraia, Barbara A; Needham, Belinda L; Rehkopf, David H; Adler, Nancy E; Lin, Jue; Blackburn, Elizabeth H; Epel, Elissa S

2014-12-01

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. 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. 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. Regular consumption of sugar-sweetened sodas might influence metabolic disease development through accelerated cell aging.

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

A study to evaluate the effect of nootropic drug-piracetam on DNA damage in leukocytes and macrophages.

PubMed

Singh, Sarika; Goswami, Poonam; Swarnkar, Supriya; Singh, Sheelendra Pratap; Wahajuddin; Nath, Chandishwar; Sharma, Sharad

2011-11-27

Piracetam is a nootropic drug that protects neurons in neuropathological and age-related diseases and the activation and modulation of peripheral blood cells in patients with neuropathological conditions is well known. Therefore, in the present study, in vivo, ex vivo, and in vitro tests were conducted to investigate the effect of piracetam on leukocytes and macrophages. Lipopolysaccharide (LPS) causes oxidative DNA damage; thus, in the present study, LPS was used as a tool to induce DNA damage. In vivo experiments were conducted on Sprague Dawley rats, and piracetam (600mg/kg, oral) was provided for five consecutive days. On the fifth day, a single injection of LPS (10mg/kg, i.p.) was administered. Three hours after LPS injection, blood leukocytes and peritoneal macrophages were collected and processed, and a variety of different assays were conducted. Ex vivo treatments were performed on isolated rat blood leukocytes, and in vitro experiments were conducted on rat macrophage cell line J774A.1. Cell viability and the level of reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and DNA damage were estimated in untreated (control) and piracetam-, LPS- and LPS+piracetam-treated leukocytes and macrophages. In vivo experiments revealed that rats pretreated with piracetam were significantly protected against LPS-induced increases in ROS levels and DNA damage. Ex vivo isolated leukocytes and J774A.1 cells treated with LPS exhibited augmented ROS levels and DNA damage, which were attenuated with piracetam treatment. Thus, the present study revealed the salutary effect of piracetam against LPS-induced oxidative stress and DNA damage in leukocytes and macrophages. Copyright © 2011 Elsevier B.V. All rights reserved.

Good Features to Correlate for Visual Tracking

NASA Astrophysics Data System (ADS)

Gundogdu, Erhan; Alatan, A. Aydin

2018-05-01

During the recent years, correlation filters have shown dominant and spectacular results for visual object tracking. The types of the features that are employed in these family of trackers significantly affect the performance of visual tracking. The ultimate goal is to utilize robust features invariant to any kind of appearance change of the object, while predicting the object location as properly as in the case of no appearance change. As the deep learning based methods have emerged, the study of learning features for specific tasks has accelerated. For instance, discriminative visual tracking methods based on deep architectures have been studied with promising performance. Nevertheless, correlation filter based (CFB) trackers confine themselves to use the pre-trained networks which are trained for object classification problem. To this end, in this manuscript the problem of learning deep fully convolutional features for the CFB visual tracking is formulated. In order to learn the proposed model, a novel and efficient backpropagation algorithm is presented based on the loss function of the network. The proposed learning framework enables the network model to be flexible for a custom design. Moreover, it alleviates the dependency on the network trained for classification. Extensive performance analysis shows the efficacy of the proposed custom design in the CFB tracking framework. By fine-tuning the convolutional parts of a state-of-the-art network and integrating this model to a CFB tracker, which is the top performing one of VOT2016, 18% increase is achieved in terms of expected average overlap, and tracking failures are decreased by 25%, while maintaining the superiority over the state-of-the-art methods in OTB-2013 and OTB-2015 tracking datasets.

Relationship between leukocyte telomere length and personality traits in healthy subjects.

PubMed

Sadahiro, R; Suzuki, A; Enokido, M; Matsumoto, Y; Shibuya, N; Kamata, M; Goto, K; Otani, K

2015-02-01

It has been shown that certain personality traits are related to mortality and disease morbidity, but the biological mechanism linking them remains unclear. Telomeres are tandem repeat DNA sequences located at the ends of chromosomes, and shorter telomere length is a predictor of mortality and late-life disease morbidity. Thus, it is possible that personality traits influence telomere length. In the present study, we examined the relationship of leukocyte telomere length with personality traits in healthy subjects. The subjects were 209 unrelated healthy Japanese who were recruited from medical students at 4th-5th grade. Assessment of personality traits was performed by the Revised NEO Personality Inventory (NEO-PI-R) and the Temperament and Character Inventory (TCI). Leukocyte relative telomere length was determined by a quantitative real-time PCR method for a ratio of telomere/single copy gene. In the stepwise multiple regression analysis, shorter telomere length was related to lower scores of neuroticism (P<0.01) and conscientiousness (P<0.05) of the NEO-PI-R, and lower scores of harm avoidance (P<0.05) and reward dependence (P<0.05) of the TCI. The present study suggests that leukocyte telomere length is associated with some personality traits, and this association may be implicated in the relationship between personality traits and mortality. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Leukocyte Inclusion within a Platelet Rich Plasma-Derived Fibrin Scaffold Stimulates a More Pro-Inflammatory Environment and Alters Fibrin Properties

PubMed Central

Anitua, Eduardo; Zalduendo, Mar; Troya, María; Padilla, Sabino; Orive, Gorka

2015-01-01

One of the main differences among platelet-rich plasma (PRP) products is the inclusion of leukocytes that may affect the biological efficacy of these autologous preparations. The purpose of this study was to evaluate whether the addition of leukocytes modified the morphological, biomechanical and biological properties of PRP under normal and inflammatory conditions. The release of pro-inflammatory cytokines from plasma rich in growth factors (PRGF) and leukocyte-platelet rich plasma (L-PRP) scaffolds was determined by enzyme-linked immunosorbent assay (ELISA) and was significantly increased under an inflammatory condition when leukocytes were included in the PRP. Fibroblasts and osteoblasts treated with L-PRP, under an inflammatory situation, underwent a greater activation of NFĸB pathway, proliferated significantly less and secreted a higher concentration of pro-inflammatory cytokines. These cellular events were assessed through Western blot and fluorimetric and ELISA methods, respectively. Therefore, the inclusion of leukocytes induced significantly higher pro-inflammatory conditions. PMID:25823008

Platelet and leukocyte activation, atherosclerosis and inflammation in European and South Asian men.

PubMed

Dotsenko, O; Chaturvedi, N; Thom, S A McG; Wright, A R; Mayet, J; Shore, A; Schalkwijk, C; Hughes, A D

2007-10-01

Increased platelet activation occurs in ischemic heart disease (IHD), but increased platelet activation is also seen in cerebrovascular atherosclerosis and peripheral artery disease. It is not clear therefore whether platelet activation is an indicator of IHD or a marker of generalized atherosclerosis and inflammation. South Asian subjects are at high risk of IHD, but little is known regarding differences in platelet and leukocyte function between European and South Asian subjects. Fifty-four male subjects (age 49-79 years) had coronary artery calcification measured by multislice computed tomography (CT), aortic atherosclerosis assessed by measurement of carotid-femoral pulse wave velocity (aortic PWV), and femoral and carotid atherosclerosis measured by B-mode ultrasound. Platelet and leukocyte activation was assessed by flow cytometry of platelet-monocyte complexes (PMC), platelet expression of PAC-1 binding site and CD62P, and expression of L-selectin on leukocytes. Elevated circulating PMC correlated significantly with elevated aortic PWV and PMC were higher in subjects with femoral plaques. In contrast PMC did not differ by increasing coronary artery calcification category or presence of carotid plaques. Higher numbers of PMC were independently related to elevated levels of C-reactive protein (CRP), higher aortic PWV, hypertension and smoking in a multivariate model. Markers of platelet and leukocyte activation did not differ significantly by ethnicity. Increased PMC are related to the extent of aortic and femoral atherosclerosis rather than coronary or carotid atherosclerosis. The association between elevated CRP and increased PMC suggests that inflammation in relation to generalized atherosclerosis may play an important role in PMC activation.

The associations between leukocyte, erythrocyte or platelet, and metabolic syndrome in different genders of Chinese

PubMed Central

Zhou, Pingping; Meng, Zhaowei; Liu, Ming; Ren, Xiaojun; Zhu, Mei; He, Qing; Zhang, Qing; Liu, Li; Song, Kun; Jia, Qiang; Tan, Jian; Li, Xue; Liu, Na; Hu, Tianpeng; Upadhyaya, Arun

2016-01-01

Abstract Leukocyte, erythrocyte or platelet and metabolic syndrome (MS) are closely correlated, and there exist gender differences. We aimed to explore the associations between the hematological parameters and MS in different genders of Chinese. This cross-sectional study included 32,900 participants (20,733 males, 12,167 females) who were enrolled in a health examination. Clinical data including anthropometric measurements and serum parameters were collected. The associations between hematological parameters and MS of both genders were analyzed separately. Odds ratio (OR) of MS was calculated by binary logistic regression models. All hematological parameters were related to MS. With leukocyte and erythrocyte counts rising, the risks of developing MS increased in both genders, which was more obvious in women. For instance, in model 3, the ORs of MS in leukocyte quartiles in females were from 1.333 to 2.045 (P < 0.01), while in males, from 1.238 to 1.675 (P < 0.01). Platelet seemed as a protective factor in males. Model 1 and model 3 in quartile 2 demonstrated ORs of 0.922 (P < 0.05) and 0.912 (P < 0.05). However, platelet acted as risk factor in female. For instance, the ORs were 1.253 (P < 0.01), 1.461 (P < 0.01), and 1.322 (P < 0.01) in platelet quartile 4 of all 3 models in female. Gender has influences on the associations between leukocyte, erythrocyte or platelet, and MS. In both genders, higher levels of leukocyte and erythrocyte increased risks of MS. For men, platelet was a protective factor, but for women, platelet seemed as a risk factor. PMID:27858856

The associations between leukocyte, erythrocyte or platelet, and metabolic syndrome in different genders of Chinese.

PubMed

Zhou, Pingping; Meng, Zhaowei; Liu, Ming; Ren, Xiaojun; Zhu, Mei; He, Qing; Zhang, Qing; Liu, Li; Song, Kun; Jia, Qiang; Tan, Jian; Li, Xue; Liu, Na; Hu, Tianpeng; Upadhyaya, Arun

2016-11-01

Leukocyte, erythrocyte or platelet and metabolic syndrome (MS) are closely correlated, and there exist gender differences. We aimed to explore the associations between the hematological parameters and MS in different genders of Chinese. This cross-sectional study included 32,900 participants (20,733 males, 12,167 females) who were enrolled in a health examination. Clinical data including anthropometric measurements and serum parameters were collected. The associations between hematological parameters and MS of both genders were analyzed separately. Odds ratio (OR) of MS was calculated by binary logistic regression models. All hematological parameters were related to MS. With leukocyte and erythrocyte counts rising, the risks of developing MS increased in both genders, which was more obvious in women. For instance, in model 3, the ORs of MS in leukocyte quartiles in females were from 1.333 to 2.045 (P < 0.01), while in males, from 1.238 to 1.675 (P < 0.01). Platelet seemed as a protective factor in males. Model 1 and model 3 in quartile 2 demonstrated ORs of 0.922 (P < 0.05) and 0.912 (P < 0.05). However, platelet acted as risk factor in female. For instance, the ORs were 1.253 (P < 0.01), 1.461 (P < 0.01), and 1.322 (P < 0.01) in platelet quartile 4 of all 3 models in female. Gender has influences on the associations between leukocyte, erythrocyte or platelet, and MS. In both genders, higher levels of leukocyte and erythrocyte increased risks of MS. For men, platelet was a protective factor, but for women, platelet seemed as a risk factor.

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

Role of flexural stiffness of leukocyte microvilli in adhesion dynamics

NASA Astrophysics Data System (ADS)

Wu, Tai-Hsien; Qi, Dewei

2018-03-01

Previous work reported that microvillus deformation has an important influence on dynamics of cell adhesion. However, the existing studies were limited to the extensional deformation of microvilli and did not consider the effects of their bending deformation on cell adhesion. This Rapid Communication investigates the effects of flexural stiffness of microvilli on the rolling process related to adhesion of leukocytes by using a lattice-Boltzmann lattice-spring method (LLM) combined with adhesive dynamics (AD) simulations. The simulation results reveal that the flexural stiffness of microvilli and their bending deformation have a profound effect on rolling velocity and adhesive forces. As the flexural stiffness of the microvilli decreases, their bending angles increase, resulting in an increase in the number of receptor-ligand bonds and adhesive bonding force and a decrease in the rolling velocity of leukocytes. The effects of flexural stiffness on deformation and adhesion represent crucial factors involved in cell adhesion.

Total and Differential Leukocyte Counts in Relation to Incidence of Diabetes Mellitus: A Prospective Population-Based Cohort Study.

PubMed

Borné, Yan; Smith, J Gustav; Nilsson, Peter M; Melander, Olle; Hedblad, Bo; Engström, Gunnar

2016-01-01

High concentrations of leukocytes in blood have been associated with diabetes mellitus. This prospective study aimed to explore whether total and differential leukocyte counts are associated with incidence of diabetes. A missense variant R262W in the SH2B3 (SH2B adaptor protein 3) gene, coding for a protein that negatively regulates hematopoietic cell proliferation, was also studied in relation to incidence of diabetes. Leukocyte count and its subtypes (neutrophils, lymphocytes and mixed cells) were analyzed in 26,667 men and women, 45-73 years old, from the population-based Malmö Diet and Cancer study. Information about the R262W polymorphism (rs3184504) in SH2B3 was genotyped in 24,489 subjects. Incidence of diabetes was studied during a mean follow-up of 14 years. Cox proportional hazards regression was used to examine incidence of diabetes by total and differential leukocyte counts. Mendelian randomization analysis using R262W as an instrumental variable was performed with two-stage least squares regression. A total of 2,946 subjects developed diabetes during the follow-up period. After taking several possible confounders into account, concentrations of total leukocyte count, neutrophils and lymphocytes were all significantly associated with incidence of diabetes. The adjusted hazard ratios (95% confidence interval; quartile 4 vs quartile 1) were 1.37 (1.22-1.53) for total leukocytes, 1.33 (1.19-1.49) for neutrophils and 1.29 (1.15-1.44) for lymphocytes. The R262W polymorphism was strongly associated with leukocytes (0.11x109 cells/l per T allele, p = 1.14 x10-12), lymphocytes (p = 4.3 x10-16), neutrophils (p = 8.0 x10-6) and mixed cells (p = 3.0 x10-6). However, there was no significant association between R262W and fasting glucose, HbA1c or incidence of diabetes. Concentrations of total leukocytes, neutrophils and lymphocytes are associated with incidence of diabetes. However, the lack of association with the R262W polymorphism suggests that the associations

Real-time digital imaging of leukocyte-endothelial interaction in ischemia-reperfusion injury (IRI) of the rat cremaster muscle.

PubMed

Thiele, Jan R; Goerendt, Kurt; Stark, G Bjoern; Eisenhardt, Steffen U

2012-08-05

Ischemia-reperfusion injury (IRI) has been implicated in a large array of pathological conditions such as cerebral stroke, myocardial infarction, intestinal ischemia as well as following transplant and cardiovascular surgery. Reperfusion of previously ischemic tissue, while essential for the prevention of irreversible tissue injury, elicits excessive inflammation of the affected tissue. Adjacent to the production of reactive oxygen species, activation of the complement system and increased microvascular permeability, the activation of leukocytes is one of the principle actors in the pathological cascade of inflammatory tissue damage during reperfusion. Leukocyte activation is a multistep process consisting of rolling, firm adhesion and transmigration and is mediated by a complex interaction between adhesion molecules in response to chemoattractants such as complement factors, chemokines, or platelet-activating factor. While leukocyte rolling in postcapillary venules is predominantly mediated by the interaction of selectins with their counter ligands, firm adhesion of leukocytes to the endothelium is selectin-controlled via binding to intercellular adhesion molecules (ICAM) and vascular cellular adhesion molecules (VCAM). Gold standard for the in vivo observation of leukocyte-endothelial interaction is the technique of intravital microscopy, first described in 1968. Though various models of IRI (ischemia-reperfusion injury) have been described for various organs, only few are suitable for direct visualization of leukocyte recruitment in the microvascular bed on a high level of image quality. We here promote the digital intravital epifluorescence microscopy of the postcapillary venule in the cremasteric microcirculation of the rat as a convenient method to qualitatively and quantitatively analyze leukocyte recruitment for IRI-research in striated muscle tissue and provide a detailed manual for accomplishing the technique. We further illustrate common pitfalls and

Association between global DNA hypomethylation in leukocytes and risk of breast cancer

PubMed Central

Choi, Ji-Yeob; James, Smitha R.; Link, Petra A.; McCann, Susan E.; Hong, Chi-Chen; Davis, Warren; Nesline, Mary K.; Ambrosone, Christine B.; Karpf, Adam R.

2009-01-01

Background: Global DNA hypomethylation may result in chromosomal instability and oncogene activation, and as a surrogate of systemic methylation activity, may be associated with breast cancer risk. Methods: Samples and data were obtained from women with incident early-stage breast cancer (I–IIIa) and women who were cancer free, frequency matched on age and race. In preliminary analyses, genomic methylation of leukocyte DNA was determined by measuring 5-methyldeoxycytosine (5-mdC), as well as methylation analysis of the LINE-1-repetitive DNA element. Further analyses used only 5-mdC levels. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of breast cancer in relation to amounts of methylation. Results: In a subset of samples tested (n = 37), 5-mdC level was not correlated with LINE-1 methylation. 5-mdC level in leukocyte DNA was significantly lower in breast cancer cases than healthy controls (P = 0.001), but no significant case–control differences were observed with LINE-1 methylation (P = 0.176). In the entire data set, we noted significant differences in 5-mdC levels in leukocytes between cases (n = 176) and controls (n = 173); P value < 0.001. Compared with women in the highest 5-mdC tertile (T3), women in the second (T2; OR = 1.49, 95% CI = 0.84–2.65) and lowest tertile (T1; OR = 2.86, 95% CI = 1.65–4.94) had higher risk of breast cancer (P for trend ≤0.001). Among controls only and cases and controls combined, only alcohol intake was found to be inversely associated with methylation levels. Conclusion: These findings suggest that leukocyte DNA hypomethylation is independently associated with development of breast cancer. PMID:19584139

Association between global DNA hypomethylation in leukocytes and risk of breast cancer.

PubMed

Choi, Ji-Yeob; James, Smitha R; Link, Petra A; McCann, Susan E; Hong, Chi-Chen; Davis, Warren; Nesline, Mary K; Ambrosone, Christine B; Karpf, Adam R

2009-11-01

Global DNA hypomethylation may result in chromosomal instability and oncogene activation, and as a surrogate of systemic methylation activity, may be associated with breast cancer risk. Samples and data were obtained from women with incident early-stage breast cancer (I-IIIa) and women who were cancer free, frequency matched on age and race. In preliminary analyses, genomic methylation of leukocyte DNA was determined by measuring 5-methyldeoxycytosine (5-mdC), as well as methylation analysis of the LINE-1-repetitive DNA element. Further analyses used only 5-mdC levels. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of breast cancer in relation to amounts of methylation. In a subset of samples tested (n = 37), 5-mdC level was not correlated with LINE-1 methylation. 5-mdC level in leukocyte DNA was significantly lower in breast cancer cases than healthy controls (P = 0.001), but no significant case-control differences were observed with LINE-1 methylation (P = 0.176). In the entire data set, we noted significant differences in 5-mdC levels in leukocytes between cases (n = 176) and controls (n = 173); P value < 0.001. Compared with women in the highest 5-mdC tertile (T3), women in the second (T2; OR = 1.49, 95% CI = 0.84-2.65) and lowest tertile (T1; OR = 2.86, 95% CI = 1.65-4.94) had higher risk of breast cancer (P for trend < or = 0.001). Among controls only and cases and controls combined, only alcohol intake was found to be inversely associated with methylation levels. These findings suggest that leukocyte DNA hypomethylation is independently associated with development of breast cancer.

Higher Circulating Leukocytes in Women with PCOS is Reversed by Aerobic Exercise

PubMed Central

Covington, Jeffrey D.; Tam, Charmaine S.; Pasarica, Magdalena; Redman, Leanne M.

2014-01-01

Polycystic ovary syndrome (PCOS) is characterized by insulin resistance, elevated circulating leukocytes, and hypothesized to have higher adipose tissue inflammation. Aerobic exercise reduces circulating leukocytes and improves insulin sensitivity in obese individuals, but the effect of exercise on inflammation in PCOS is not known. We investigated circulating leukocytes, insulin sensitivity by euglycemic-hyperinsulinemic clamp, serum pro- and anti-inflammatory markers (hsCRP, TNF-α, total and high molecular weight adiponectin), and abdominal subcutaneous adipose tissue (SAT) gene expression of proinflammatory markers in 8 PCOS women and 8 obese control females matched for BMI. Additionally, in a prospective study, the 8 women with PCOS underwent a 16-week aerobic exercise regimen with the same measures performed post-intervention. Compared to controls, white blood cell counts (WBC) were 30% higher (p = 0.04) and circulating total adiponectin levels were 150% lower (p = 0.03) in women with PCOS at baseline/pre-exercise conditions. SAT gene expression of macrophage migration inhibitory factor (MIF, p < 0.01) and interleukin-6 (IL-6, p < 0.05) were also lower in women with PCOS. In response to 16 weeks of aerobic exercise, insulin sensitivity improved (p < 0.01) and WBC counts decreased (p = 0.02). The exercise-induced change in WBC and circulating neutrophils correlated inversely with changes in glucose disposal rate (r= -0.73, p=0.03; and r= -0.82, p=0.01, respectively). Aerobic exercise reduced serum leptin (p < 0.05) after 4 weeks, trended to reduce the ratio of leptin-to-high molecular weight adiponectin (p < 0.1) by the 8th week, and significantly increased serum dehydroepiandrosterone sulfate (DHEA-S, p < 0.001) after 16 weeks. In conclusion, women with PCOS have higher circulating leukocytes compared to controls, which can be reversed by aerobic exercise and is associated with improvements in insulin sensitivity. PMID:25446648

Motion-compensated speckle tracking via particle filtering

NASA Astrophysics Data System (ADS)

Liu, Lixin; Yagi, Shin-ichi; Bian, Hongyu

2015-07-01

Recently, an improved motion compensation method that uses the sum of absolute differences (SAD) has been applied to frame persistence utilized in conventional ultrasonic imaging because of its high accuracy and relative simplicity in implementation. However, high time consumption is still a significant drawback of this space-domain method. To seek for a more accelerated motion compensation method and verify if it is possible to eliminate conventional traversal correlation, motion-compensated speckle tracking between two temporally adjacent B-mode frames based on particle filtering is discussed. The optimal initial density of particles, the least number of iterations, and the optimal transition radius of the second iteration are analyzed from simulation results for the sake of evaluating the proposed method quantitatively. The speckle tracking results obtained using the optimized parameters indicate that the proposed method is capable of tracking the micromotion of speckle throughout the region of interest (ROI) that is superposed with global motion. The computational cost of the proposed method is reduced by 25% compared with that of the previous algorithm and further improvement is necessary.

[Chlamydia trachomaatis DNA in leukocytes of peripheral blood from neonates].

PubMed

López-Hurtado, Marcela; Cuevas-Recillas, Karla N; Flores-Salazar, Verónica R; Guerra-Infante, Fernando M

2015-01-01

Diagnosis of Chlamydia trachomatis infection in newborns is difficult; however, this diagnosis is performed by cell culture or by detection of IgM antibodies against C. trachomatis. Detection of C. trachomatis DNA in peripheral blood leukocytes using polymer chain reaction (PCR) may be a better tool for the diagnosis of infection by this pathogen. A total of 44 premature newborns, all weighing less than 2500g, were included in the study. A blood sample and nasopharyngeal lavages were obtained from each newborn. Leukocyte DNA was obtained by phenol-chloroform extraction technique. Detection of C. trachomatis was performed by amplifying the ompA gene using the PCR endpoint. Cell culture tests and the detection of IgM antibodies against C. trachomatis by microimmunofluorescence assay were also performed. Twenty newborns were PCR-positive (45.5%), with this test being significantly associated with the presence of pneumonia (RR=2.28; 95%CI: 1.01 to 5.17; P=.035). The cell culture of nasopharyngeal lavage was positive in only 7 samples and no significant association was observed with any clinical or laboratory data. The titer of IgM antibodies against C. trachomatis associated with PCR-positive was 1:32 (RR=2.74; 95%CI: 1.21 to 6.23; P=.008), however this titer was not associated with the presence of pneumonia. DNA detection in peripheral blood leukocytes could be useful for diagnosis of C. trachomatis infection. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Bacterial reduction by cell salvage washing and leukocyte depletion filtration.

PubMed

Waters, Jonathan H; Tuohy, Marion J; Hobson, Donna F; Procop, Gary

2003-09-01

Blood conservation techniques are being increasingly used because of the increased cost and lack of availability of allogeneic blood. Cell salvage offers great blood savings opportunities but is thought to be contraindicated in a number of areas (e.g., blood contaminated with bacteria). Several outcome studies have suggested the safety of this technique in trauma and colorectal surgery, but many practitioners are still hesitant to apply cell salvage in the face of frank bacterial contamination. This study was undertaken to assess the efficacy of bacterial removal when cell salvage was combined with leukocyte depletion filtration. Expired packed erythrocytes were obtained and inoculated with a fixed amount of a stock bacteria (Escherichia coli American Type Culture Collections [ATCC] 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, or Bacteroides fragilis ATCC 25285) in amounts ranging from 2,000 to 4,000 colony forming units/ml. The blood was processed via a cell salvage machine. The washed blood was then filtered using a leukocyte reduction filter. The results for blood taken during each step of processing were compared using a repeated-measures design. Fifteen units of blood were contaminated with each of the stock bacteria. From the prewash sample to the postfiltration sample, 99.0%, 99.6%, 100%, and 97.6% of E. coli, S. aureus, P. aeruginosa, and B. fragilis were removed, respectively. Significant but not complete removal of contaminating bacteria was seen. An increased level of patient safety may be added to cell salvage by including a leukocyte depletion filter when salvaging blood that might be grossly contaminated with bacteria.

Fractalkine and CX3CR1 Mediate a Novel Mechanism of Leukocyte Capture, Firm Adhesion, and Activation under Physiologic Flow

PubMed Central

Fong, Alan M.; Robinson, Lisa A.; Steeber, Douglas A.; Tedder, Thomas F.; Yoshie, Osamu; Imai, Toshio; Patel, Dhavalkumar D.

1998-01-01

Leukocyte migration into sites of inflammation involves multiple molecular interactions between leukocytes and vascular endothelial cells, mediating sequential leukocyte capture, rolling, and firm adhesion. In this study, we tested the role of molecular interactions between fractalkine (FKN), a transmembrane mucin-chemokine hybrid molecule expressed on activated endothelium, and its receptor (CX3CR1) in leukocyte capture, firm adhesion, and activation under physiologic flow conditions. Immobilized FKN fusion proteins captured resting peripheral blood mononuclear cells at physiologic wall shear stresses and induced firm adhesion of resting monocytes, resting and interleukin (IL)-2–activated CD8+ T lymphocytes and IL-2–activated NK cells. FKN also induced cell shape change in firmly adherent monocytes and IL-2–activated lymphocytes. CX3CR1-transfected K562 cells, but not control K562 cells, firmly adhered to FKN-expressing ECV-304 cells (ECV-FKN) and tumor necrosis factor α–activated human umbilical vein endothelial cells. This firm adhesion was not inhibited by pertussis toxin, EDTA/EGTA, or antiintegrin antibodies, indicating that the firm adhesion was integrin independent. In summary, FKN mediated the rapid capture, integrin-independent firm adhesion, and activation of circulating leukocytes under flow. Thus, FKN and CX3CR1 mediate a novel pathway for leukocyte trafficking. PMID:9782118

Leukocytes as risk markers for cardiovascular disease in adolescents: association with birth characteristics, nutritional status and biochemical tests

PubMed Central

do Prado, Pedro Paulo; de Faria, Franciane Rocha; de Faria, Eliane Rodrigues; Franceschini, Sylvia do Carmo Castro; Priore, Silvia Eloiza

2016-01-01

Abstract Objective: To evaluate the correlation between the number of leukocytes and cardiovascular risks associated with birth characteristics, nutritional status and biochemical tests. Methods: Cross-sectional study developed with 475 adolescents, born between 1992 and 2001, in the municipality of Viçosa (MG). Maternal medical records were analyzed in the hospital units, and the following was recorded: birth weight and length, head circumference, chest circumference, Apgar score, gestational age. In adolescents, body mass index, skinfold thickness, body composition, blood count, biochemical tests and clinical variables were also assessed. The statistical analyses was carried out using Statistical Package for Social Sciences (SPSS) version 20.0 and Data Analysis and Statistical Software (STATA) with Kruskal–Wallis, Mann–Whitney, chi-square or Fisher's exact tests and Linear Regression. Significance level was set at α<0.05. The study was approved by the Research Ethics Committee of UFV for studies with human subjects. Results: Weight and birth length, head and chest circumference were higher among boys. In adolescents, the number of leukocytes was higher in individuals with excess weight and body fat and high adiposity index, waist-to-height ratio and waist circumference. Only altered triglycerides showed differences between leukocyte medians. Regardless of the anthropometric variable of the final regression model, the stage of adolescence, number of platelets, eosinophils, monocytes and lymphocytes were associated with the increase in leukocytes. Conclusions: The birth variables were not associated with changes in leukocyte numbers, whereas the anthropometric variables were good indicators for a higher leukocyte count, regardless of the stage of adolescence and gender. PMID:26572104

Leukocyte telomere length and diabetes status, duration, and control: the 1999-2002 National Health and Nutrition Examination Survey.

PubMed

Menke, Andy; Casagrande, Sarah; Cowie, Catherine C

2015-09-29

Studies investigating the association between telomere length and diabetes have been inconsistent, and there are few data available investigating the associations of telomere length with diabetes duration and control. We evaluated the relationship of leukocyte telomere length with diabetes, and the relationship of leukocyte telomere length with diabetes duration and poor glucose control among people with diabetes. We used data from the 1999-2002 National Health and Nutrition Examination Survey, a representative sample of the US civilian non-institutionalized population. In 3921 participants, leukocyte telomere length was measured and diabetes status was determined based on a previous diagnosis, hemoglobin A1c ≥ 6.5 %, or fasting glucose ≥ 126 mg/dL. The odds ratios (95 % confidence intervals) of diabetes associated with the first, second, and third quartile of leukocyte telomere length, compared to the highest quartile, was 2.09 (1.46-2.98), 1.74 (1.30-2.31), and 1.08 (0.76-1.54), respectively (p-trend < 0.01), in unadjusted models and 0.74 (0.48-1.14), 0.91 (0.61-1.34), and 0.87 (0.59-1.29), respectively (p-trend = 0.20), in multivariable adjusted models. Among participants with diabetes, unadjusted and adjusted leukocyte telomere length was not associated with diabetes duration or glucose control based on an hemoglobin A1c < 7 or < 8 % (all p > 0.05). In this study of the US general population, leukocyte telomere length was not associated with diabetes status, diabetes duration, or diabetes control.

Application of TrackEye in equine locomotion research.

PubMed

Drevemo, S; Roepstorff, L; Kallings, P; Johnston, C J

1993-01-01

TrackEye is an analysis system, which is applicable for equine biokinematic studies. It covers the whole process from digitizing of images, automatic target tracking and analysis. Key components in the system are an image work station for processing of video images and a high-resolution film-to-video scanner for 16-mm film. A recording module controls the input device and handles the capture of image sequences into a videodisc system, and a tracking module is able to follow reference markers automatically. The system offers a flexible analysis including calculations of markers displacements, distances and joint angles, velocities and accelerations. TrackEye was used to study effects of phenylbutazone on the fetlock and carpal joint angle movements in a horse with a mild lameness caused by osteo-arthritis in the fetlock joint of a forelimb. Significant differences, most evident before treatment, were observed in the minimum fetlock and carpal joint angles when contralateral limbs were compared (p < 0.001). The minimum fetlock angle and the minimum carpal joint angle were significantly greater in the lame limb before treatment compared to those 6, 37 and 49 h after the last treatment (p < 0.001).

HDAC inhibitors: modulating leukocyte differentiation, survival, proliferation and inflammation.

PubMed

Sweet, Matthew J; Shakespear, Melanie R; Kamal, Nabilah A; Fairlie, David P

2012-01-01

Therapeutic effects of histone deacetylase (HDAC) inhibitors in cancer models were first linked to their ability to cause growth arrest and apoptosis of tumor cells. It is now clear that these agents also have pleiotropic effects on angiogenesis and the immune system, and some of these properties are likely to contribute to their anti-cancer activities. It is also emerging that inhibitors of specific HDACs affect the differentiation, survival and/or proliferation of distinct immune cell populations. This is true for innate immune cells such as macrophages, as well as cells of the acquired immune system, for example, T-regulatory cells. These effects may contribute to therapeutic profiles in some autoimmune and chronic inflammatory disease models. Here, we review our current understanding of how classical HDACs (HDACs 1-11) and their inhibitors impact on differentiation, survival and proliferation of distinct leukocyte populations, as well as the likely relevance of these effects to autoimmune and inflammatory disease processes. The ability of HDAC inhibitors to modulate leukocyte survival may have implications for the rationale of developing selective inhibitors as anti-inflammatory drugs.

A link between occupant and vehicle accelerations during common driving tasks.

PubMed

Mathias, Anne C; Shibata, Peggy A; Sprague, James K

2014-01-01

When evaluating occupant motions during driving tasks, it is desirable to have a well-established correlation between vehicle and occupant accelerations. Therefore, this study demonstrated a methodology to quantify accelerations experienced by the driver of a passenger vehicle and compare them to associated vehicle motions. Acceleration levels were measured at the seat and the driver’s head, cervical spine, and lumbar spine during six non-collision driving tasks. Tasks included mounting a 127 mm (5 in) -high curb, crossing railroad tracks, driving on a rough road, braking heavily from 13.4 m/s (30 mph), having a 89 mm (3.5 in)-diameter roller sequentially pass under two tires, and dropping one tire from a 171-mm (6.75 in) height. The driver experienced peak resultant accelerations of similar magnitudes across all trials. Peak body accelerations were less than 1.2 g, including 0.82 g lumbar acceleration during heavy braking and 0.88 g head acceleration during the curb mount. These preliminary measurements are comparable to or lower than accelerations experienced during non-driving activities such as sitting quickly. This study contributes to the scientific understanding of accelerations experienced by vehicle occupants and demonstrates the potential to relate vehicle and occupant accelerations during common driving activities that do not involve collisions.

CD11c- and CD11b-expressing mouse leukocytes transport single Toxoplasma gondii tachyzoites to the brain

PubMed Central

Courret, Nathalie; Darche, Sylvie; Sonigo, Pierre; Milon, Geneviève; Buzoni-Gâtel, Dominique; Tardieux, Isabelle

2006-01-01

The protozoan parasite Toxoplasma gondii enters hosts through the intestinal mucosa and colonizes distant tissues such as the brain, where its progeny persists for a lifetime. We investigated the role of CD11c- and CD11b-expressing leukocytes in T gondii transport during the early step of parasitism from the mouse small intestine and during subsequent parasite localization in the brain. Following intragastric inoculation of cyst-containing parasites in mice, CD11c+ dendritic cells from the intestinal lamina propria, the Peyer patches, and the mesenteric lymph nodes were parasitized while in the blood, parasites were associated with the CD11c- CD11b+ monocytes. Using adoptive transfer experiments, we demonstrated that these parasitized cells triggered a parasitic process in the brain of naive recipient mice. Ex vivo analysis of parasitized leukocytes showed that single tachyzoites remained at the cell periphery, often surrounded by the host cell plasma membrane, but did not divide. Using either a dye that labels circulating leukocytes or an antibody known to prevent CD11b+ circulating leukocytes from leaving the microvascular bed lumen, and chimeric mice in which the hematopoietic cells expressed the green fluorescent protein, we established that T gondii zoites hijacked CD11b+ leukocytes to reach the brain extravascular space. PMID:16051744

The spectrum of resistance in SR/CR mice: the critical role of chemoattraction in the cancer/leukocyte interaction.

PubMed

Riedlinger, Gregory; Adams, Jonathan; Stehle, John R; Blanks, Michael J; Sanders, Anne M; Hicks, Amy M; Willingham, Mark C; Cui, Zheng

2010-05-03

Spontaneous regression/complete resistance (SR/CR) mice are a unique colony of mice that possess an inheritable, natural cancer resistance mediated primarily by innate cellular immunity. This resistance is effective against sarcoma 180 (S180) at exceptionally high doses and these mice remain healthy. In this study, we challenged SR/CR mice with additional lethal transplantable mouse cancer cell lines to determine their resistance spectrum. The ability of these transplantable cancer cell lines to induce leukocyte infiltration was quantified and the percentage of different populations of responding immune cells was determined using flow cytometry. In comparison to wild type (WT) mice, SR/CR mice showed significantly higher resistance to all cancer cell lines tested. However, SR/CR mice were more sensitive to MethA sarcoma (MethA), B16 melanoma (B16), LL/2 lung carcinoma (LL/2) and J774 lymphoma (J774) than to sarcoma 180 (S180) and EL-4 lymphoma (EL-4). Further mechanistic studies revealed that this lower resistance to MethA and LL/2 was due to the inability of these cancer cells to attract SR/CR leukocytes, leading to tumor cell escape from resistance mechanism. This escape mechanism was overcome by co-injection with S180, which could attract SR/CR leukocytes allowing the mice to resist higher doses of MethA and LL/2. S180-induced cell-free ascites fluid (CFAF) co-injection recapitulated the results obtained with live S180 cells, suggesting that this chemoattraction by cancer cells is mediated by diffusible molecules. We also tested for the first time whether SR/CR mice were able to resist additional cancer cell lines prior to S180 exposure. We found that SR/CR mice had an innate resistance against EL-4 and J774. Our results suggest that the cancer resistance in SR/CR mice is based on at least two separate processes: leukocyte migration/infiltration to the site of cancer cells and recognition of common surface properties on cancer cells. The infiltration of SR

Increasing platelet concentrations in leukocyte-reduced platelet-rich plasma decrease collagen gene synthesis in tendons.

PubMed

Boswell, Stacie G; Schnabel, Lauren V; Mohammed, Hussni O; Sundman, Emily A; Minas, Tom; Fortier, Lisa A

2014-01-01

Platelet-rich plasma (PRP) is used for the treatment of tendinopathy. There are numerous PRP preparations, and the optimal combination of platelets and leukocytes is not known. Within leukocyte-reduced PRP (lrPRP), there is a plateau effect of platelet concentration, with increasing platelet concentrations being detrimental to extracellular matrix synthesis. Controlled laboratory study. Different formulations of lrPRP with respect to the platelet:leukocyte ratio were generated from venous blood of 8 horses. Explants of the superficial digital flexor tendon were cultured in lrPRP products for 96 hours. Platelet-derived growth factor-BB (PDGF-BB), tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), and interleukin-1β (IL-1β) concentrations were determined in the media by enzyme-linked immunosorbent assay. Gene expression in tendon tissue for collagen type I and III (COL1A1 and COL3A1, respectively), matrix metalloproteinase-3 and -13 (MMP-3 and MMP-13, respectively), cartilage oligomeric matrix protein (COMP), and IL-1β was determined. Data were divided into 3 groups of lrPRP based on the ratio of platelets:leukocytes and evaluated to determine the effect of platelet concentration. Complete blood counts verified leukocyte reduction and platelet enrichment in all PRP preparations. In the lrPRP preparation, the anabolic growth factors PDGF-BB and TGF-β1 were increased with increasing platelet concentrations, and the catabolic cytokine IL-1β was decreased with increasing platelet concentrations. Increasing the platelet concentration resulted in a significant reduction in COL1A1 and COL3A1 synthesis in tendons. Increasing the platelet concentration within lrPRP preparations results in the delivery of more anabolic growth factors and less proinflammatory cytokines, but the biological effect on tendons is diminished metabolism as indicated by a decrease in the synthesis of both COL1A1 and COL3A1. Together, this information suggests that

Glucose-dependent leukocyte activation in patients with type 2 diabetes mellitus, familial combined hyperlipidemia and healthy controls.

PubMed

de Vries, Marijke A; Alipour, Arash; Klop, Boudewijn; van de Geijn, Gert-Jan M; Janssen, Hans W; Njo, Tjin L; van der Meulen, Noëlle; Rietveld, Arie P; Liem, Anho H; Westerman, Elsbeth M; de Herder, Wouter W; Cabezas, Manuel Castro

2015-02-01

Leukocyte activation has been associated with vascular complications in type 2 diabetes mellitus (T2DM). Hyperglycemia may be involved in this leukocyte activation. Our aim was to investigate the role of elevated glucose concentrations on leukocyte activation in patients with a wide range of insulin sensitivity. Leukocyte activation was determined after ingestion of 75 gram glucose in subjects with T2DM, familial combined hyperlipidemia (FCH) and healthy controls. Leukocyte activation markers were measured by flow cytometry. Postprandial changes were calculated as the area under the curve (AUC), and the incremental area under the curve corrected for baseline values (dAUC). 51 Subjects (20 T2DM, 17 FCH and 14 controls) were included. Fasting neutrophil CD66b expression and CD66b-AUC were respectively 36% and 39% higher in T2DM patients than in controls (p=0.004 and p=0.003). Fasting neutrophil CD66b expression correlated positively with glucose-AUC (Spearman's rho 0.481, p<0.001) and HbA1c (rho 0.433, p=0.002). Although fasting monocyte CD11b expression was not significantly different between subjects, monocyte CD11b-AUC was 26% higher in T2DM than in controls (p=0.006). Similar trends were observed for FCH patients. Monocyte CD11b-dAUC correlated positively with glucose-AUC (rho 0.322, p=0.022) and HbA1c (rho 0.319, p=0.023). These data suggest that both acute and chronic hyperglycemia, associated with insulin resistance as seen in T2DM and FCH, are involved in the increased fasting and postprandial leukocyte activation observed in these conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

Leukocyte-inspired biodegradable particles that selectively and avidly adhere to inflamed endothelium in vitro and in vivo

NASA Astrophysics Data System (ADS)

Sakhalkar, Harshad S.; Dalal, Milind K.; Salem, Aliasger K.; Ansari, Ramin; Fu, Jie; Kiani, Mohammad F.; Kurjiaka, David T.; Hanes, Justin; Shakesheff, Kevin M.; Goetz, Douglas J.

2003-12-01

We exploited leukocyte-endothelial cell adhesion chemistry to generate biodegradable particles that exhibit highly selective accumulation on inflamed endothelium in vitro and in vivo. Leukocyte-endothelial cell adhesive particles exhibit up to 15-fold higher adhesion to inflamed endothelium, relative to noninflamed endothelium, under in vitro flow conditions similar to that present in blood vessels, a 6-fold higher adhesion to cytokine inflamed endothelium relative to non-cytokine-treated endothelium in vivo, and a 10-fold enhancement in adhesion to trauma-induced inflamed endothelium in vivo due to the addition of a targeting ligand. The leukocyte-inspired particles have adhesion efficiencies similar to that of leukocytes and were shown to target each of the major inducible endothelial cell adhesion molecules (E-selectin, P-selectin, vascular cell adhesion molecule 1, and intercellular adhesion molecule 1) that are up-regulated at sites of pathological inflammation. The potential for targeted drug delivery to inflamed endothelium has significant implications for the improved treatment of an array of pathologies, including cardiovascular disease, arthritis, inflammatory bowel disease, and cancer.

High molecular weight kininogen regulates platelet-leukocyte interactions by bridging Mac-1 and glycoprotein Ib.

PubMed

Chavakis, Triantafyllos; Santoso, Sentot; Clemetson, Kenneth J; Sachs, Ulrich J H; Isordia-Salas, Irma; Pixley, Robin A; Nawroth, Peter P; Colman, Robert W; Preissner, Klaus T

2003-11-14

Leukocyte-platelet interaction is important in mediating leukocyte adhesion to a thrombus and leukocyte recruitment to a site of vascular injury. This interaction is mediated at least in part by the beta2-integrin Mac-1 (CD11b/CD18) and its counter-receptor on platelets, glycoprotein Ibalpha (GPIbalpha). High molecular weight kininogen (HK) was previously shown to interact with both GPIbalpha and Mac-1 through its domains 3 and 5, respectively. In this study we investigated the ability of HK to interfere with the leukocyte-platelet interaction. In a purified system, HK binding to GPIbalpha was inhibited by HK domain 3 and the monoclonal antibody (mAb) SZ2, directed against the epitope 269-282 of GPIbalpha, whereas mAb AP1, directed to the region 201-268 of GPIbalpha had no effect. In contrast, mAb AP1 inhibited the Mac-1-GPIbalpha interaction. Binding of GPIbalpha to Mac-1 was enhanced 2-fold by HK. This effect of HK was abrogated in the presence of HK domains 3 or 5 or peptides from the 475-497 region of the carboxyl terminus of domain 5 as well as in the presence of mAb SZ2 but not mAb AP1. Whereas no difference in the affinity of the Mac-1-GPIbalpha interaction was observed in the absence or presence of HK, maximal binding of GPIbalpha to Mac-1 doubled in the presence of HK. Moreover, HK/HKa increased the Mac-1-dependent adhesion of myelomonocytic U937 cells and K562 cells transfected with Mac-1 to immobilized GPIbalpha or to GPIbalpha-transfected Chinese hamster ovary cells. Finally, Mac-1-dependent adhesion of neutrophils to surface-adherent platelets was enhanced by HK. Thus, HK can bridge leukocytes with platelets by interacting via its domain 3 with GPIbalpha and via its domain 5 with Mac-1 thereby augmenting the Mac-1-GPIbalpha interaction. These distinct molecular interactions of HK with leukocytes and platelets contribute to the regulation of the adhesive behavior of vascular cells and provide novel molecular targets for reducing atherothrombotic

Effects of simvastatin, ezetimibe and simvastatin/ezetimibe on mitochondrial function and leukocyte/endothelial cell interactions in patients with hypercholesterolemia.

PubMed

Hernandez-Mijares, Antonio; Bañuls, Celia; Rovira-Llopis, Susana; Diaz-Morales, Noelia; Escribano-Lopez, Irene; de Pablo, Carmen; Alvarez, Angeles; Veses, Silvia; Rocha, Milagros; Victor, Victor M

2016-04-01

Cholesterol-lowering therapy has been related with several beneficial effects; however, its influence on oxidative stress and endothelial function is not fully elucidated. To investigate the effect of simvastatin and ezetimibe on mitochondrial function and leukocyte-endothelium interactions in polymorphonuclear cells of hyperlipidemic patients. Thirty-nine hyperlipidemic patients were randomly assigned to one of two groups: one received simvastatin (40 mg/day) and the other received ezetimibe (10 mg/day) for 4 weeks, after which both groups were administered combined therapy for an additional 4-week period. Lipid profile, mitochondrial parameters (oxygen consumption, reactive oxygen species (ROS) and membrane potential), glutathione levels, superoxide dismutase activity, catalase activity and leukocyte/endothelial cell interactions and adhesion molecules -VCAM-1, ICAM-1, E-selectin, were evaluated. An improvement in lipid profile was observed after administration of simvastatin or ezetimibe alone (LDLc: -40.2 vs -19.6%, respectively), though this effect was stronger with the former (p < 0.001), and a further reduction was registered when the two were combined (LDLc: -50.7% vs -56.8%, respectively). In addition to this, simvastatin, ezetimibe and simvastatin + ezetimibe significantly increased oxygen consumption, membrane potential and glutathione content, and decreased levels of ROS, thereby improving mitochondrial function. Furthermore, simvastatin + ezetimibe increased catalase activity. In addition, simvastatin and simvastatin/ezetimibe improved leukocyte/endothelium interactions by decreasing leukocyte rolling and adhesion and increasing leukocyte rolling velocity. Finally, simvastatin, ezetimibe and simvastatin + ezetimibe reduced levels of the adhesion molecule ICAM-1, and ezetimibe + simvastatin significantly decreased levels of E-selectin. Co-administration of simvastatin and ezetimibe has an additive cholesterol-lowering effect and beneficial consequences

Utility of the nitroblue tetrazolium reduction test for assessment of reactive oxygen species production by seminal leukocytes and spermatozoa.

PubMed

Esfandiari, Navid; Sharma, Rakesh K; Saleh, Ramadan A; Thomas, Anthony J; Agarwal, Ashok

2003-01-01

The purpose of this study was to evaluate the ability of spermatozoa and leukocytes in semen to produce reactive oxygen species (ROS) by using nitroblue tetrazolium (NBT) staining and to examine the association between NBT staining and levels of ROS as measured by chemiluminescence. Twenty-one infertility patients (leukocytospermia; n = 8; nonleukocytospermia, n = 13) and 9 healthy donors were included. Standard semen analysis and density gradient centrifugation were performed to test NBT staining, ROS, and total antioxidant capacity. A ROS-total antioxidant capacity (ROS-TAC) score was calculated by using principal component analysis. In the leukocytospermic group, after separation on a density gradient, the percentage of NBT-positive staining was significantly higher in sperm suspensions contaminated with leukocytes (median [25th, 75th percentiles]; 70% [61%, 79%]) compared to the nonleukocytospermic group (14.5% [9%, 25.5%]; P =.03) and donors (7% [3%, 11%]; P =.02), respectively. A strong positive correlation was seen between levels of ROS in whole ejaculates and NBT-positive staining in leukocytes (r = 0.59; P <.0006) and in leukocyte fractions (r = 0.72; P <.0001) after density gradient separation. Similarly, ROS was positively correlated with excessive cytoplasmic retention in spermatozoa from whole ejaculates and abnormal spermatozoa after separation on density gradients (r = 0.72; P <.0001). The ROS-TAC score was inversely correlated with NBT staining in leukocytes in whole ejaculates (r = -0.960, P <.0007) and in both leukocyte fractions (r = -0.39; P <.04) and spermatozoa with cytoplasmic retention (r = -0.38; P <.04). Our results indicate that the NBT reduction test can be used to assess the contribution of seminal leukocytes and defective spermatozoa towards ROS generation in semen. Levels of ROS assessed by chemiluminescence assay are strongly correlated with the results of NBT staining.

Characterization of Vertical Impact Device Acceleration Pulses Using Parametric Assessment: Phase I

DTIC Science & Technology

2015-04-01

vehicle seating systems. Previous research on the VID (Knox, T., Pellettiere, J., Perry, C., Plaga , J., Bonfeld, J., 2008; Veridian Contract Report...BIBLIOGRAPHY/REFERENCES Knox, T., Pellettiere, J., Perry, C., Plaga , J., Bonfeld, J. (2008). New Sensors to Track Head Acceleration During Possible

Physical Models for Particle Tracking Simulations in the RF Gap

DOE Office of Scientific and Technical Information (OSTI.GOV)

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.

Data fusion for target tracking and classification with wireless sensor network

NASA Astrophysics Data System (ADS)

Pannetier, Benjamin; Doumerc, Robin; Moras, Julien; Dezert, Jean; Canevet, Loic

2016-10-01

In this paper, we address the problem of multiple ground target tracking and classification with information obtained from a unattended wireless sensor network. A multiple target tracking (MTT) algorithm, taking into account road and vegetation information, is proposed based on a centralized architecture. One of the key issue is how to adapt classical MTT approach to satisfy embedded processing. Based on track statistics, the classification algorithm uses estimated location, velocity and acceleration to help to classify targets. The algorithms enables tracking human and vehicles driving both on and off road. We integrate road or trail width and vegetation cover, as constraints in target motion models to improve performance of tracking under constraint with classification fusion. Our algorithm also presents different dynamic models, to palliate the maneuvers of targets. The tracking and classification algorithms are integrated into an operational platform (the fusion node). In order to handle realistic ground target tracking scenarios, we use an autonomous smart computer deposited in the surveillance area. After the calibration step of the heterogeneous sensor network, our system is able to handle real data from a wireless ground sensor network. The performance of system is evaluated in a real exercise for intelligence operation ("hunter hunt" scenario).

Effects of radiotherapy and chemotherapy on angiogenesis and leukocyte infiltration in rectal cancer.

PubMed

Baeten, Coen I M; Castermans, Karolien; Lammering, Guido; Hillen, Femke; Wouters, Bradly G; Hillen, Harry F P; Griffioen, Arjan W; Baeten, Cornelius G M I

2006-11-15

We and others have shown that angiogenesis and leukocyte infiltration are important prognostic factors in rectal cancer. However, little is known about its possible changes in response to radiotherapy (RTX), which is frequently given to rectal tumors as a neoadjuvant treatment to improve the prognosis. We therefore investigated the biologic effects of RTX on these parameters using fresh-frozen biopsy samples of tumor and normal mucosa tissue before and after RTX. Biopsy samples were taken from a total of 34 patients before and after either a short course or long course of RTX combined with chemotherapy. The following parameters were analyzed by immunohistochemistry, flow cytometry, or quantitative real-time polymerase chain reaction: Microvessel density, leukocyte infiltration, proliferating epithelial and tumor cells, proliferating endothelial cells, adhesion molecule expression on endothelial cells, and the angiogenic mRNA profile. The tumor biopsy samples taken after RTX treatment demonstrated a significant decrease in microvessel density and the number of proliferating tumor cells and proliferating endothelial cells (p < 0.001). In contrast, the leukocyte infiltration, the levels of basic fibroblast growth factor in carcinoma tissue, and the adhesion molecule expression on endothelial cells in normal as well as carcinoma tissue increased significantly (p < 0.05). Our data show that together with an overall decrease in tumor cell and endothelial cell proliferation, RTX results in an increase in the expression of adhesion molecules that stimulate leukocyte infiltration. This suggests the possibility that, in addition to its direct cytotoxic effect, radiation may also stimulate an immunologic tumor response that could contribute to the documented improvement in local tumor control and distal failure rate of rectal cancers.

Ethylene formation by polymorphonuclear leukocytes. Role of myeloperoxidase

PubMed Central

1978-01-01

Ethylene formation from the thioethers, beta-methylthiopropionaldehyde (methional) and 2-keto-4-thiomethylbutyric acid by phagocytosing polymorphonuclear leukocytes (PMNs) was found to be largely dependent on myeloperoxidase (MPO). Conversion was less than 10% of normal when MPO-deficient PMNs were employed; formation by normal PMNs was inhibited by the peroxidase inhibitors, azide, and cyanide, and a model system consisting of MPO, H2O2, chloride (or bromide) and EDTA was found which shared many of the properties of the predominant PMN system. MPO-independent mechanisms of ethylene formation were also identified. Ethylene formation from methional by phagocytosing eosinophils and by H2O2 in the presence or absence of catalase was stimulated by azide. The presence of MPO-independent, azide-stimulable systems in the PMN preparations was suggested by the azide stimulation of ethylene formation from methional when MPO-deficient leukocytes were employed. Ethylene formation by dye-sensitized photooxidation was also demonstrated and evidence obtained for the involvement of singlet oxygen (1O2). These findings are discussed in relation to the participation of H2O2, hydroxyl radicals, the superoxide anion and 1O2 in the formation of ethylene by PMNs and by the MPO model system. PMID:212502

Protein levels of ADAM10, BACE1, and PSEN1 in platelets and leukocytes of Alzheimer's disease patients.

PubMed

Bram, Jessyka Maria de França; Talib, Leda Leme; Joaquim, Helena Passarelli Giroud; Sarno, Tamires Alves; Gattaz, Wagner Farid; Forlenza, Orestes Vicente

2018-05-29

The clinical diagnosis of Alzheimer's disease (AD) is a probabilistic formulation that may lack accuracy particularly at early stages of the dementing process. Abnormalities in amyloid-beta precursor protein (APP) metabolism and in the level of APP secretases have been demonstrated in platelets, and to a lesser extent in leukocytes, of AD patients, with conflicting results. The aim of the present study was to compare the protein level of the APP secretases A-disintegrin and metalloprotease 10 (ADAM10), Beta-site APP-cleaving enzyme 1 (BACE1), and presenilin-1 (PSEN1) in platelets and leukocytes from 20 non-medicated older adults with AD and 20 healthy elders, and to determine the potential use of these biomarkers to discriminate cases of AD from controls. The protein levels of all APP secretases were significantly higher in platelets compared to leukocytes. We found statistically a significant decrease in ADAM10 (52.5%, p < 0.0001) and PSEN1 (32%, p = 0.02) in platelets from AD patients compared to controls, but not in leukocytes. Combining all three secretases to generate receiver-operating characteristic (ROC) curves, we found a good discriminatory effect (AD vs. controls) when using platelets (the area under the curve-AUC-0.90, sensitivity 88.9%, specificity 66.7%, p = 0.003), but not in leukocytes (AUC 0.65, sensitivity 77.8%, specificity 50.0%, p = 0.2). Our findings indicate that platelets represent a better biological matrix than leukocytes to address the peripheral level of APP secretases. In addition, combining the protein level of ADAM10, BACE1, and PSEN1 in platelets, yielded a good accuracy to discriminate AD from controls.

[Leukocytes as risk markers for cardiovascular disease in adolescents: association with birth characteristics, nutritional status and biochemical tests].

PubMed

do Prado Junior, Pedro Paulo; Faria, Franciane Rocha de; Faria, Eliane Rodrigues de; Franceschini, Sylvia do Carmo Castro; Priore, Silvia Eloiza

2016-01-01

To evaluate the correlation between the number of leukocytes and cardiovascular risks associated with birth characteristics, nutritional status and biochemical tests. Cross-sectional study developed with 475 adolescents, born between 1992 and 2001, in the municipality of Viçosa (MG). Maternal medical records were analyzed in the hospital units, and the following was recorded: birth weight and length, head circumference, chest circumference, Apgar score, gestational age. In adolescents, body mass index, skinfold thickness, body composition, blood count, biochemical tests and clinical variables were also assessed. The statistical analyses was carried out using Statistical Package for Social Sciences (SPSS) version 20.0 and Data Analysis and Statistical Software (STATA) with Kruskal-Wallis, Mann-Whitney, chi-square or Fisher's exact tests and Linear Regression. Significance level was set at α<0.05. The study was approved by the Research Ethics Committee of UFV for studies with human subjects. Weight and birth length, head and chest circumference were higher among boys. In adolescents, the number of leukocytes was higher in individuals with excess weight and body fat and high adiposity index, waist-to-height ratio and waist circumference. Only altered triglycerides showed differences between leukocyte medians. Regardless of the anthropometric variable of the final regression model, the stage of adolescence, number of platelets, eosinophils, monocytes and lymphocytes were associated with the increase in leukocytes. The birth variables were not associated with changes in leukocyte numbers, whereas the anthropometric variables were good indicators for a higher leukocyte count, regardless of the stage of adolescence and gender. Copyright © 2015 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

Multiple, targeted deficiencies in selectins reveal a predominant role for P-selectin in leukocyte recruitment

PubMed Central

Robinson, Stephen D.; Frenette, Paul S.; Rayburn, Helen; Cummiskey, Marge; Ullman-Culleré, Mollie; Wagner, Denisa D.; Hynes, Richard O.

1999-01-01

We extend our previous analyses of mice deficient in selectins by describing the generation and comparative phenotype of mice lacking one, two, or three selectins after sequential ablation of the murine genes encoding P-, E-, and L-selectins. All mice deficient in selectins are viable and fertile as homozygotes. However, mice missing both P- and E-selectins (PE−/−), and mice missing all three selectins (ELP−/−) develop mucocutaneous infections that eventually lead to death. Mice deficient in multiple selectins display varying degrees of leukocytosis, resulting in part from alterations in leukocyte rolling and recruitment. PE−/− mice, ELP−/− mice, and mice missing both P- and L-selectins (PL−/−) show drastic reductions in leukocyte rolling and in extravasation of neutrophils in thioglycollate-induced peritonitis. In a separate inflammatory model (ragweed-induced peritoneal eosinophilia), we demonstrate P-selectin to be both necessary and sufficient for the recruitment of eosinophils. The phenotype of mice missing both E- and L-selectins (EL−/−) is less severe than those seen in the other double knockouts. Comparisons among the double knockouts suggest that P-selectin normally cooperates with both E- and L-selectins. Our results indicate a preeminent role for P-selectin in regulating leukocyte behavior in mice. Data from the ELP−/− mice indicate, however, that all three selectins are important to leukocyte homeostasis and efficient neutrophil recruitment. PMID:10500197

Usefulness of Leukocyte Esterase Test Versus Rapid Strep Test for Diagnosis of Acute Strep Pharyngitis.

PubMed

Nibhanipudi, Kumara V

2015-01-01

A study to compare the usage of throat swab testing for leukocyte esterase on a test strip(urine dip stick-multi stick) to rapid strep test for rapid diagnosis of Group A Beta hemolytic streptococci in cases of acute pharyngitis in children. The testing of throat swab for leukocyte esterase on test strip currently used for urine testing may be used to detect throat infection and might be as useful as rapid strep. All patients who come with a complaint of sore throat and fever were examined clinically for erythema of pharynx, tonsils and also for any exudates. Informed consent was obtained from the parents and assent from the subjects. 3 swabs were taken from pharyngo-tonsillar region, testing for culture, rapid strep & Leukocyte Esterase. Total number is 100. Cultures 9(+); for rapid strep== 84(-) and16 (+); For LE== 80(-) and 20(+) From data configuration Rapid Strep versus LE test don't seem to be a random (independent) assignment but extremely aligned. The Statistical results show rapid and LE show very agreeable results. Calculated Value of Chi Squared Exceeds Tabulated under 1 Degree Of Freedom (P<.0.0001) reject Null HYPOTHESIS and Conclude Alternative Conclusions: Leukocyte esterase on throat swab is as useful as rapid strep test for rapid diagnosis of strep pharyngitis on test strip currently used for urine dip stick causing acute pharyngitis in children.

Relationship between shift work and peripheral total and differential leukocyte counts in Chinese steel workers.

PubMed

Lu, Li-Fen; Wang, Chao-Ping; Tsai, I-Ting; Hung, Wei-Chin; Yu, Teng-Hung; Wu, Cheng-Ching; Hsu, Chia-Chang; Lu, Yung-Chuan; Chung, Fu-Mei; Jean, Mei-Chu Yen

2016-01-01

Even though shift work has been suspected to be a risk factor for cardiovascular disease, little research has been done to determine the logical underlying inflammation mechanisms. This study investigated the association between shift work and circulating total and differential leukocyte counts among Chinese steel workers. The subjects were 1,654 line workers in a steel plant, who responded to a cross-sectional survey with a questionnaire on basic attributes, life style, and sleep. All workers in the plant received a periodic health checkup. Total and differential leukocytes counts were also examined in the checkup. Shift workers had higher rates of alcohol use, smoking, poor sleep, poor physical exercise, and obesity than daytime workers. In further analysis, we found that the peripheral total WBC, monocyte, neutrophil, and lymphocyte counts were also greater in shift workers than in daytime workers. When subjects were divided into quartiles according to total WBC, neutrophil, monocyte, and lymphocyte counts, increased leukocyte count was associated with shift work. Using stepwise linear regression analysis, smoking, obesity, and shift work were independently associated with total WBC, monocyte, neutrophil, and lymphocyte counts. This study indicates that peripheral total and differential leukocyte counts are significantly higher in shift workers, which suggests that shift work may be a risk factor of cardiovascular disease. Applicable intervention strategies are needed for prevention of cardiovascular disease for shift workers.

Tracking coherent structures in massively-separated and turbulent flows

NASA Astrophysics Data System (ADS)

Rockwood, Matthew; Huang, Yangzi; Green, Melissa

2018-01-01

Coherent vortex structures are tracked in simulations of massively-separated and turbulent flows. Topological Lagrangian saddle points are found using intersections of the positive and negative finite-time Lyapunov exponent ridges, and these points are then followed in order to track individual coherent structure motion both in a complex interacting three-dimensional flow (turbulent channel) and during vortex formation (two-dimensional bluff body shedding). For a simulation of wall-bounded turbulence in a channel flow, tracking Lagrangian saddles shows that the average structure convection speed exhibits a similar trend as a previously published result based on velocity and pressure correlations, giving validity to the method. When this tracking method is applied in a study of a circular cylinder in cross-flow it shows that Lagrangian saddles rapidly accelerate away from the cylinder surface as the vortex sheds. This saddle behavior is compared with the time-resolved static pressure distribution on the circular cylinder, yielding locations on a cylinder surface where common sensors could detect this phenomenon, which is not available from force measurements or vortex circulation calculations. The current method of tracking coherent structures yields insight into the behavior of the coherent structures in both of the diverse flows presented, highlighting the breadth of its potential application.

The method of segmentation of leukocytes in information-measuring systems on the basis of light microscopy

NASA Astrophysics Data System (ADS)

Nikitaev, V. G.; Pronichev, A. N.; Polyakov, E. V.; Zaharenko, Yu V.

2018-01-01

The paper considers the problem of leukocytes segmentation in microscopic images of bone marrow smears for automated diagnosis of the blood system diseases. The method was proposed to solve the problem of segmentation of contacting leukocytes in images of bone marrow smears. The method is based on the analysis of structure of objects of a separation and distances filter in combination with the watershed method and distance transformation method.

Hierarchical biointerfaces assembled by leukocyte-inspired particles for specifically recognizing cancer cells.

PubMed

Meng, Jingxin; Liu, Hongliang; Liu, Xueli; Yang, Gao; Zhang, Pengchao; Wang, Shutao; Jiang, Lei

2014-09-24

By mimicking certain biochemical and physical attributes of biological cells, bio-inspired particles have attracted great attention for potential biomedical applications based on cell-like biological functions. Inspired by leukocytes, hierarchical biointerfaces are designed and prepared based on specific molecules-modified leukocyte-inspired particles. These biointerfaces can efficiently recognize cancer cells from whole blood samples through the synergistic effect of molecular recognition and topographical interaction. Compared to flat, mono-micro or nano-biointerfaces, these micro/nano hierarchical biointerfaces are better able to promote specific recognition interactions, resulting in an enhanced cell-capture efficiency. It is anticipated that this study may provide promising guidance to develop new bio-inspired hierarchical biointerfaces for biomedical applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fast Track Initiative: Building a Global Compact for Education. Education Notes

ERIC Educational Resources Information Center

Human Development Network Education, 2005

2005-01-01

This note series is intended to summarize lessons learned and key policy findings on the World Bank's work in education. "Fast Track Initiative" ("FTI") was launched in 2002 as a partnership between donor and developing countries to accelerate progress towards the Millennium Development Goal (MDG) of universal primary education. "FTI" is built on…

O-glycans direct selectin ligands to lipid rafts on leukocytes

PubMed Central

Shao, Bojing; Yago, Tadayuki; Setiadi, Hendra; Wang, Ying; Mehta-D’souza, Padmaja; Fu, Jianxin; Crocker, Paul R.; Rodgers, William; Xia, Lijun; McEver, Rodger P.

2015-01-01

Palmitoylated cysteines typically target transmembrane proteins to domains enriched in cholesterol and sphingolipids (lipid rafts). P-selectin glycoprotein ligand-1 (PSGL-1), CD43, and CD44 are O-glycosylated proteins on leukocytes that associate with lipid rafts. During inflammation, they transduce signals by engaging selectins as leukocytes roll in venules, and they move to the raft-enriched uropods of polarized cells upon chemokine stimulation. It is not known how these glycoproteins associate with lipid rafts or whether this association is required for signaling or for translocation to uropods. Here, we found that loss of core 1-derived O-glycans in murine C1galt1−/− neutrophils blocked raft targeting of PSGL-1, CD43, and CD44, but not of other glycosylated proteins, as measured by resistance to solubilization in nonionic detergent and by copatching with a raft-resident sphingolipid on intact cells. Neuraminidase removal of sialic acids from wild-type neutrophils also blocked raft targeting. C1galt1−/− neutrophils or neuraminidase-treated neutrophils failed to activate tyrosine kinases when plated on immobilized anti–PSGL-1 or anti-CD44 F(ab′)2. Furthermore, C1galt1−/− neutrophils incubated with anti–PSGL-1 F(ab′)2 did not generate microparticles. In marked contrast, PSGL-1, CD43, and CD44 moved normally to the uropods of chemokine-stimulated C1galt1−/− neutrophils. These data define a role for core 1-derived O-glycans and terminal sialic acids in targeting glycoprotein ligands for selectins to lipid rafts of leukocytes. Preassociation of these glycoproteins with rafts is required for signaling but not for movement to uropods. PMID:26124096

O-glycans direct selectin ligands to lipid rafts on leukocytes.

PubMed

Shao, Bojing; Yago, Tadayuki; Setiadi, Hendra; Wang, Ying; Mehta-D'souza, Padmaja; Fu, Jianxin; Crocker, Paul R; Rodgers, William; Xia, Lijun; McEver, Rodger P

2015-07-14

Palmitoylated cysteines typically target transmembrane proteins to domains enriched in cholesterol and sphingolipids (lipid rafts). P-selectin glycoprotein ligand-1 (PSGL-1), CD43, and CD44 are O-glycosylated proteins on leukocytes that associate with lipid rafts. During inflammation, they transduce signals by engaging selectins as leukocytes roll in venules, and they move to the raft-enriched uropods of polarized cells upon chemokine stimulation. It is not known how these glycoproteins associate with lipid rafts or whether this association is required for signaling or for translocation to uropods. Here, we found that loss of core 1-derived O-glycans in murine C1galt1(-/-) neutrophils blocked raft targeting of PSGL-1, CD43, and CD44, but not of other glycosylated proteins, as measured by resistance to solubilization in nonionic detergent and by copatching with a raft-resident sphingolipid on intact cells. Neuraminidase removal of sialic acids from wild-type neutrophils also blocked raft targeting. C1galt1(-/-) neutrophils or neuraminidase-treated neutrophils failed to activate tyrosine kinases when plated on immobilized anti-PSGL-1 or anti-CD44 F(ab')2. Furthermore, C1galt1(-/-) neutrophils incubated with anti-PSGL-1 F(ab')2 did not generate microparticles. In marked contrast, PSGL-1, CD43, and CD44 moved normally to the uropods of chemokine-stimulated C1galt1(-/-) neutrophils. These data define a role for core 1-derived O-glycans and terminal sialic acids in targeting glycoprotein ligands for selectins to lipid rafts of leukocytes. Preassociation of these glycoproteins with rafts is required for signaling but not for movement to uropods.

Symplectic orbit and spin tracking code for all-electric storage rings

DOE PAGES

Talman, Richard M.; Talman, John D.

2015-07-22

Proposed methods for measuring the electric dipole moment (EDM) of the proton use an intense, polarized proton beam stored in an all-electric storage ring “trap.” At the “magic” kinetic energy of 232.792 MeV, proton spins are “frozen,” for example always parallel to the instantaneous particle momentum. Energy deviation from the magic value causes in-plane precession of the spin relative to the momentum. Any nonzero EDM value will cause out-of-plane precession—measuring this precession is the basis for the EDM determination. A proposed implementation of this measurement shows that a proton EDM value of 10 –29e–cm or greater will produce a statisticallymore » significant, measurable precession after multiply repeated runs, assuming small beam depolarization during 1000 s runs, with high enough precision to test models of the early universe developed to account for the present day particle/antiparticle population imbalance. This paper describes an accelerator simulation code, eteapot, a new component of the Unified Accelerator Libraries (ual), to be used for long term tracking of particle orbits and spins in electric bend accelerators, in order to simulate EDM storage ring experiments. Though qualitatively much like magnetic rings, the nonconstant particle velocity in electric rings gives them significantly different properties, especially in weak focusing rings. Like the earlier code teapot (for magnetic ring simulation) this code performs exact tracking in an idealized (approximate) lattice rather than the more conventional approach, which is approximate tracking in a more nearly exact lattice. The Bargmann-Michel-Telegdi (BMT) equation describing the evolution of spin vectors through idealized bend elements is also solved exactly—original to this paper. Furthermore the idealization permits the code to be exactly symplectic (with no artificial “symplectification”). Any residual spurious damping or antidamping is sufficiently small to permit

Motion-compensated compressed sensing for dynamic contrast-enhanced MRI using regional spatiotemporal sparsity and region tracking: Block LOw-rank Sparsity with Motion-guidance (BLOSM)

PubMed Central

Chen, Xiao; Salerno, Michael; Yang, Yang; Epstein, Frederick H.

2014-01-01

Purpose Dynamic contrast-enhanced MRI of the heart is well-suited for acceleration with compressed sensing (CS) due to its spatiotemporal sparsity; however, respiratory motion can degrade sparsity and lead to image artifacts. We sought to develop a motion-compensated CS method for this application. Methods A new method, Block LOw-rank Sparsity with Motion-guidance (BLOSM), was developed to accelerate first-pass cardiac MRI, even in the presence of respiratory motion. This method divides the images into regions, tracks the regions through time, and applies matrix low-rank sparsity to the tracked regions. BLOSM was evaluated using computer simulations and first-pass cardiac datasets from human subjects. Using rate-4 acceleration, BLOSM was compared to other CS methods such as k-t SLR that employs matrix low-rank sparsity applied to the whole image dataset, with and without motion tracking, and to k-t FOCUSS with motion estimation and compensation that employs spatial and temporal-frequency sparsity. Results BLOSM was qualitatively shown to reduce respiratory artifact compared to other methods. Quantitatively, using root mean squared error and the structural similarity index, BLOSM was superior to other methods. Conclusion BLOSM, which exploits regional low rank structure and uses region tracking for motion compensation, provides improved image quality for CS-accelerated first-pass cardiac MRI. PMID:24243528

Shorter leukocyte telomere length is associated with higher risk of infections: a prospective study of 75,309 individuals from the general population.

PubMed

Helby, Jens; Nordestgaard, Børge G; Benfield, Thomas; Bojesen, Stig E

2017-08-01

In the general population, older age is associated with short leukocyte telomere length and with high risk of infections. In a recent study of allogeneic hematopoietic cell transplantation for severe aplastic anemia, long donor leukocyte telomere length was associated with improved survival in the recipients. These findings suggest that leukocyte telomere length could possibly be a marker of immune competence. Therefore, we tested the hypothesis that shorter leukocyte telomere length is associated with higher risk of infectious disease hospitalization and infection-related death. Relative peripheral blood leukocyte telomere length was measured using quantitative polymerase chain reaction in 75,309 individuals from the general population and the individuals were followed for up to 23 years. During follow up, 9228 individuals were hospitalized with infections and infection-related death occurred in 1508 individuals. Shorter telomere length was associated with higher risk of any infection (hazard ratio 1.05 per standard deviation shorter leukocyte telomere length; 95% confidence interval 1.03-1.07) and pneumonia (1.07; 1.03-1.10) after adjustment for conventional infectious disease risk factors. Corresponding hazard ratios for infection-related death were 1.10 (1.04-1.16) for any infection and 1.11 (1.04-1.19) for pneumonia. Telomere length was not associated with risk of skin infection, urinary tract infection, sepsis, diarrheal disease, endocarditis, meningitis or other infections. In conclusion, our findings indicate that leukocyte telomere length may be a marker of immune competence. Further studies are needed to determine whether risk of infections in allogeneic hematopoietic cell transplantation recipients can be reduced by considering donor leukocyte telomere length when selecting donors. Copyright© 2017 Ferrata Storti Foundation.

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Radiation Pressure Forces, the Anomalous Acceleration, and Center of Mass Motion for the TOPEX/POSEIDON Spacecraft

NASA Technical Reports Server (NTRS)

Kubitschek, Daniel G.; Born, George H.

2000-01-01

Shortly after launch of the TOPEX/POSEIDON (T/P) spacecraft (s/c), the Precision Orbit Determination (POD) Team at NASA's Goddard Space Flight Center (GSFC) and the Center for Space Research at the University of Texas, discovered residual along-track accelerations, which were unexpected. Here, we describe the analysis of radiation pressure forces acting on the T/P s/c for the purpose of understanding and providing an explanation for the anomalous accelerations. The radiation forces acting on the T/P solar army, which experiences warping due to temperature gradients between the front and back surfaces, are analyzed and the resulting along-track accelerations are determined. Characteristics similar to those of the anomalous acceleration are seen. This analysis led to the development of a new radiation form model, which includes solar array warping and a solar array deployment deflection of as large as 2 deg. As a result of this new model estimates of the empirical along-track acceleration are reduced in magnitude when compared to the GSFC tuned macromodel and are less dependent upon beta(prime), the location of the Sun relative to the orbit plane. If these results we believed to reflect the actual orientation of the T/P solar array then motion of the solar array must influence the location of the s/c center of mass. Preliminary estimates indicate that the center of mass can vary by as much as 3 cm in the radial component of the s/c's position due to rotation of the deflected, warped solar array panel .The altimeter measurements rely upon accurate knowledge of the center of mass location relative to the s/c frame of reference. Any radial motion of the center of mass directly affects the altimeter measurements.

Prenatal Arsenic Exposure and DNA Methylation in Maternal and Umbilical Cord Blood Leukocytes

PubMed Central

Baccarelli, Andrea; Hoffman, Elaine; Tarantini, Letizia; Quamruzzaman, Quazi; Rahman, Mahmuder; Mahiuddin, Golam; Mostofa, Golam; Hsueh, Yu-Mei; Wright, Robert O.; Christiani, David C.

2012-01-01

Background: Arsenic is an epigenetic toxicant and could influence fetal developmental programming. Objectives: We evaluated the association between arsenic exposure and DNA methylation in maternal and umbilical cord leukocytes. Methods: Drinking-water and urine samples were collected when women were at ≤ 28 weeks gestation; the samples were analyzed for arsenic using inductively coupled plasma mass spectrometry. DNA methylation at CpG sites in p16 (n = 7) and p53 (n = 4), and in LINE-1 and Alu repetitive elements (3 CpG sites in each), was quantified using pyrosequencing in 113 pairs of maternal and umbilical blood samples. We used general linear models to evaluate the relationship between DNA methylation and tertiles of arsenic exposure. Results: Mean (± SD) drinking-water arsenic concentration was 14.8 ± 36.2 μg/L (range: < 1–230 μg/L). Methylation in LINE-1 increased by 1.36% [95% confidence interval (CI): 0.52, 2.21%] and 1.08% (95% CI: 0.07, 2.10%) in umbilical cord and maternal leukocytes, respectively, in association with the highest versus lowest tertile of total urinary arsenic per gram creatinine. Arsenic exposure was also associated with higher methylation of some of the tested CpG sites in the promoter region of p16 in umbilical cord and maternal leukocytes. No associations were observed for Alu or p53 methylation. Conclusions: Exposure to higher levels of arsenic was positively associated with DNA methylation in LINE-1 repeated elements, and to a lesser degree at CpG sites within the promoter region of the tumor suppressor gene p16. Associations were observed in both maternal and fetal leukocytes. Future research is needed to confirm these results and determine if these small increases in methylation are associated with any health effects. PMID:22466225

Raised plasma soluble P-selectin in peripheral arterial occlusive disease enhances leukocyte adhesion.

PubMed

Woollard, K J; Kling, D; Kulkarni, S; Dart, A M; Jackson, S; Chin-Dusting, J

2006-01-06

Raised levels of soluble P-selectin (sP-selectin) have been reported in the plasma of patients with vascular diseases; however, the functional importance of this ligand remains unclear. In this study we have examined a potential role for plasma sP-selectin in regulating neutrophil adhesion in patients with peripheral arterial occlusive disease (PAOD). Patients with PAOD had significantly higher levels of sP-selectin (mean+/-SD: 73.3+/-13.0 versus 16.7+/-6.4 ng/mL) and enhanced whole blood leukocyte adhesion to platelets under shear. To examine whether the raised sP-selectin levels can directly influence leukocyte adhesion, isolated neutrophils were incubated with plasma from PAOD patients before and after immunodepletion of sP-selectin. Neutrophil adhesion to fibrinogen increased 2-fold following incubation with PAOD plasma, which was abrogated on sP-selectin immunodepletion. We subsequently demonstrated that recombinant sP-selectin dose-dependently (75 to 250 ng/mL) increased leukocyte adhesion to fibrinogen and platelet monolayers. This increase was PSGL-1 and Src kinase-dependent and correlated with an increase in sP-selectin-mediated Mac-1 activation. sP-selectin-stimulated neutrophil adhesion to platelet monolayers was inversely correlated with shear, such that at low shear (50 s(-1)) a 92.7%+/-15.7 increase in adhesion was observed decreasing to 38.5%+/-11.9 at 150 s(-1) and 10.1%+/-7.4 at 300 s(-1). These studies suggest a potentially important role for sP-selectin in modulating neutrophil adhesion in patients with PAOD, particularly at sites of low shear, where it raises the possibility that raised plasma sP-selectin levels may enhance leukocyte recruitment to vascular injury and promote disease progression.

Long leukocyte telomere length in prostate cancer patients at diagnosis is associated with poor metastasis-free and cancer-specific survival.

PubMed

Svenson, Ulrika; Roos, Göran; Wikström, Pernilla

2017-02-01

Previous studies have suggested that leukocyte telomere length is associated with risk of developing prostate cancer. Investigations of leukocyte telomere length as a prognostic factor in prostate cancer are, however, lacking. In this study, leukocyte telomere length was investigated both as a risk marker, comparing control subjects and patient risk groups (based on serum levels of prostate-specific antigen, tumor differentiation, and tumor stage), and as a prognostic marker for metastasis-free and cancer-specific survival. Relative telomere length was measured by a well-established quantitative polymerase chain reaction method in 415 consecutively sampled individuals. Statistical evaluation included 162 control subjects without cancer development during follow-up and 110 untreated patients with newly diagnosed localized prostate cancer at the time of blood draw. Leukocyte telomere length did not differ significantly between control subjects and patients, or between patient risk groups. Interestingly, however, and in line with our previous results in breast and kidney cancer patients, relative telomere length at diagnosis was an independent prognostic factor. Patients with long leukocyte telomeres (⩾median) had a significantly worse prostate cancer-specific and metastasis-free survival compared to patients with short telomere length. In contrast, for patients who died of other causes than prostate cancer, long relative telomere length was not coupled to shorter survival time. To our knowledge, these results are novel and give further strength to our hypothesis that leukocyte telomere length might be used as a prognostic marker in malignancy.

Flat electron beam sources for DLA accelerators

DOE PAGES

Ody, A.; Musumeci, P.; Maxson, J.; ...

2016-10-26

In this study we discuss the application of the flat beam transform to generate beams suitable for injection into slab-symmetric dielectric laser-driven accelerators (DLAs). A study of the focusing requirements to keep the particles within the tight apertures characterizing these accelerators shows the benefits of employing ultralow beam emittances. The slab geometry of the many dielectric accelerating structures strongly favors the use of flat beams with large ratio between vertical and horizontal emittances. We employ particle tracking simulations to study the application of the flat beam transform for two injector designs, a DC non relativistic photogun and a 1.6 cellmore » S-band RF photoinjector, obtaining in both cases emittance ratios between the horizontal and vertical plane in excess of 100 in agreement with simple analytical estimates. The 4 MeV RF photoinjector study-case can be directly applied to the UCLA Pegasus beamline and shows normalized emittances down to < 3 nm in the vertical dimension for beam charges up to 20 fC, enabling a two-stage DLA experiment.« less

Heart rate and leukocytes after air and ground transportation in artificially ventilated neonates: a prospective observational study.

PubMed

Grosek, Stefan; Mlakar, Gorazd; Vidmar, Ivan; Ihan, Alojz; Primozic, Janez

2009-01-01

To evaluate the effect of interhospital air and ground transportation of artificially ventilated neonates on heart rate and peripheral blood leukocyte counts. Prospective, observational study. Level III multidisciplinary Neonatal and Pediatric Intensive Care Unit. Fifty-eight near-term artificially ventilated transported neonates between May 2006 and April 2007. Day-helicopter, day- and night-ground transportation. Heart rate at retrieval, on admission to the ICU and 1 h later, and peripheral blood leukocyte counts on admission and 1 d later were compared. Fifteen neonates were transported by helicopter during the daytime (D-HEL), 20 by daytime ground and 23 by nighttime ground transportation (D-GROUND, N-GROUND). No differences in delivery mode, birth weight, gestational age, gender, primary diagnoses for transportation, response time and duration of transportation were found between the groups. Similarly, no differences in pH, pCO(2), blood pressure and skin temperature at retrieval and on admission to the ICU were found between the three groups. The mean heart rate at retrieval did not differ significantly, while on arrival in the ICU and 1 h later the D-GROUND group of patients showed a significantly higher mean heart rate compared to the D-HEL and N-GROUND groups. Moreover, leukocyte counts on arrival in the ICU showed significantly higher leukocyte counts in the D-GROUND group of patients compared to the D-HEL group of patients. These results demonstrate that there is an association between daytime ground transportation and higher heart rate and peripheral blood leukocytes.

Fluorescent staining for leukocyte chemotaxis. Eosinophil-specific fluorescence with aniline blue.

PubMed

McCrone, E L; Lucey, D R; Weller, P F

1988-11-10

To overcome problems associated with the quantitation of human eosinophil chemotaxis in micropore filters, we have developed a fluorescent method of specifically staining eosinophils in chemotactic filters. A neutral solution of aniline blue yielded bright green fluorescent staining of the cytoplasmic granules of eosinophils. Other leukocytes and contaminating neutrophils potentially present with eosinophils did not fluoresce with aniline blue. The fluorescent staining eosinophils within filters provided bright, non-fading images that facilitated visual microscopic counting and were of sufficiently high contrast, unlike those with conventional eosinophil stains, to allow image analyzer based enumeration of eosinophil chemotactic responses at levels through the filters. Although not cell type-specific, congo red and ethidium bromide also provided high contrast, fluorescent images of all leukocyte types within chemotactic filters. Fluorescent staining with aniline blue constitutes a rapid, stable and eosinophil-specific stain that facilitates the visual or image analyzer-based quantitation of eosinophil chemotaxis.

Anomaly detection driven active learning for identifying suspicious tracks and events in WAMI video

NASA Astrophysics Data System (ADS)

Miller, David J.; Natraj, Aditya; Hockenbury, Ryler; Dunn, Katherine; Sheffler, Michael; Sullivan, Kevin

2012-06-01

We describe a comprehensive system for learning to identify suspicious vehicle tracks from wide-area motion (WAMI) video. First, since the road network for the scene of interest is assumed unknown, agglomerative hierarchical clustering is applied to all spatial vehicle measurements, resulting in spatial cells that largely capture individual road segments. Next, for each track, both at the cell (speed, acceleration, azimuth) and track (range, total distance, duration) levels, extreme value feature statistics are both computed and aggregated, to form summary (p-value based) anomaly statistics for each track. Here, to fairly evaluate tracks that travel across different numbers of spatial cells, for each cell-level feature type, a single (most extreme) statistic is chosen, over all cells traveled. Finally, a novel active learning paradigm, applied to a (logistic regression) track classifier, is invoked to learn to distinguish suspicious from merely anomalous tracks, starting from anomaly-ranked track prioritization, with ground-truth labeling by a human operator. This system has been applied to WAMI video data (ARGUS), with the tracks automatically extracted by a system developed in-house at Toyon Research Corporation. Our system gives promising preliminary results in highly ranking as suspicious aerial vehicles, dismounts, and traffic violators, and in learning which features are most indicative of suspicious tracks.

Composition and functional capacity of blood mononuclear leukocyte populations from neonatal calves on standard and intensified milk replacer diets.

PubMed

Nonnecke, B J; Foote, M R; Smith, J M; Pesch, B A; Van Amburgh, M E

2003-11-01

Effects of increased dietary energy and protein on the composition and functional capacities of blood mononuclear leukocyte populations from milk replacer-fed calves were investigated. Holstein bull calves (average age: 4.2 d; n = 19) were assigned randomly to one of two treatment groups. Treatment 1 calves (n = 9) were fed a 20% crude protein, 20% fat milk replacer at a rate of 1.4% body weight of dry matter/d for 8 wk, whereas treatment 2 calves (n = 10) were fed a 30% crude protein, 20% fat milk replacer at a rate of 2.5% body weight of dry matter per day. Composition and functional capacities of mononuclear leukocyte populations from blood samples collected at 4, 18, 32, 46, and 60 d of age were characterized by flow cytometry and ex vivo cell function assays. From 11 to 60 d of age, the mean daily weight gain of treatment 2 calves (1.20 kg/d) was greater than daily weight gain of treatment 1 calves (0.55 kg/d). At 60 d of age, the mean body weight of treatment two calves was 53% (39 kg) greater than the mean body weight of treatment 1 calves. Total numbers of blood leukocytes and the composition of the mononuclear leukocyte population were unaffected by the plane of nutrition. Mitogen-induced DNA-synthesis and immunoglobulin M secretion also were unaffected by dietary treatment. Blood mononuclear leukocytes from calves on intensified diets, however, produced less interferon-gamma and more inducible nitric oxide, suggesting that increased dietary energy and protein affects specific aspects of leukocyte function associated with cell-mediated immunity. The impact of altered interferon-gamma and NO production on the calf s susceptibility to infectious disease are not known. Mononuclear leukocyte populations from all calves also demonstrated age-related changes in composition and functional capacity, likely reflecting natural exposure to infectious agents and maturation of the calfs immune system.

Studies on the mechanism of endogenous pyrogen production. II. Role of cell products in the regulation of pyrogen release from blood leukocytes.

PubMed

Bodel, P

1974-09-01

Some characteristics of the process by which endogenous pyrogen (EP), the mediator of fever, is released from cells were examined by using human blood leukocytes incubated in vitro. Studies were designed to examine a possible role for leukocyte products, including EP, in the induction, augmentation, or suppression of pyrogen release by blood leukocytes. Products of stimulated leukocytes, including a partially purified preparation of EP, did not induce significant activation of nonstimulated cells. Also, no evidence was obtained that stimulated cell products either augment or inhibit pyrogen production by other stimulated cells. A feedback control of EP production was thus not observed. A crude preparation of EP, containing other products of activated cells, maintained its pyrogenicity when incubated at pH 7.4 but not at pH 5.0. These studies thus provide no support for hypothesized control mechanisms regulating production of EP by blood leukocytes. By contrast, local inactivation of EP at inflammatory sites may modify the amount of EP entering the blood, and hence fever.

Association of peripheral total and differential leukocyte counts with obesity-related complications in young adults.

PubMed

Yoshimura, Aya; Ohnishi, Shunsuke; Orito, Chieko; Kawahara, Yukako; Takasaki, Hiroyo; Takeda, Hiroshi; Sakamoto, Naoya; Hashino, Satoshi

2015-01-01

Obesity has been demonstrated to be associated with elevated leukocytes in adults and children. This study assessed the associations between peripheral total and differential leukocyte counts and obesity-related complications in young adults. 12 obese (median age 21.5 (range 19-28) years, median BMI 35.7 (range 32.0-44.9) kg/m(2)) and 11 normal (median age 23 (range 18-27) years, median BMI 19.5 (range 18.1-21.7) kg/m(2)) adults were enrolled. Complete blood count and serum levels of liver enzymes, fasting blood glucose, insulin and lipids were measured, and the homeostasis model assessment of insulin resistance was calculated. Fat mass was calculated using a bioimpedance analysis device, and ultrasonography was performed to measure fat thickness and to detect fatty change of the liver. Total leukocyte and monocyte counts were significantly increased in obese young adults. Total leukocyte count was associated with liver enzyme levels, insulin resistance as well as visceral and subcutaneous fat thickness. Neutrophil count was associated with insulin resistance. Lymphocyte count was associated with serum liver enzymes, insulin resistance, and dyslipidemia. Monocyte count was associated with serum liver enzyme, insulin resistance, visceral and subcutaneous fat thickness, body fat mass, and percentage body fat. The results of this study suggest that chronic low-grade systemic inflammation is associated with obesity-related complications such as nonalcoholic fatty liver disease, insulin resistance, and dyslipidemia in young adults. © 2015 S. Karger GmbH, Freiburg.

Usefulness of Leukocyte Esterase Test Versus Rapid Strep Test for Diagnosis of Acute Strep Pharyngitis

PubMed Central

2015-01-01

Objective: A study to compare the usage of throat swab testing for leukocyte esterase on a test strip(urine dip stick-multi stick) to rapid strep test for rapid diagnosis of Group A Beta hemolytic streptococci in cases of acute pharyngitis in children. Hypothesis: The testing of throat swab for leukocyte esterase on test strip currently used for urine testing may be used to detect throat infection and might be as useful as rapid strep. Methods: All patients who come with a complaint of sore throat and fever were examined clinically for erythema of pharynx, tonsils and also for any exudates. Informed consent was obtained from the parents and assent from the subjects. 3 swabs were taken from pharyngo-tonsillar region, testing for culture, rapid strep & Leukocyte Esterase. Results: Total number is 100. Cultures 9(+); for rapid strep== 84(-) and16 (+); For LE== 80(-) and 20(+) Statistics: From data configuration Rapid Strep versus LE test don’t seem to be a random (independent) assignment but extremely aligned. The Statistical results show rapid and LE show very agreeable results. Calculated Value of Chi Squared Exceeds Tabulated under 1 Degree Of Freedom (P<.0.0001) reject Null Hypothesis and Conclude Alternative Conclusions: Leukocyte esterase on throat swab is as useful as rapid strep test for rapid diagnosis of strep pharyngitis on test strip currently used for urine dip stick causing acute pharyngitis in children. PMID:27335975

ON CHANGES OF GLYCOGEN CONTENT IN THE SPLEEN LEUKOCYTES DUE TO IRRADIATION AND ANTIGEN EFFECTS (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akopova, V.A.

1961-01-01

An investigation was made on 90 white mice subject to x irradiation, using a dose of 335 r (Series I), to vaccination with a brucellosis vaccine (Series II), and to a combined action of these factors (Series III and IV). When the mice received a total irradiation with a dose of 335 r, the leukocytes in the spleen imprints contained a moderate amount of glycogen varying considerably during a fortnight. The x irradiation of the same dose, followed by the action of the brucellosis vaccine, gave rise to an abrupt drop in the glycogen contert of the leukocytes. Under themore » influence of antigen, followed by x irradiation, a considerable amount of glycogen in the leukocytes and the presence of antibodies in the blood were observed. (auth)« less

[Screening with angiographic images prior to (99m)Tc-HMPAO labelled leukocyte scintigraphy in the diagnosis of periprosthetic infection].

PubMed

Granados, U; Fuster, D; Soriano, A; García, S; Bori, G; Martínez, J C; Mayoral, M; Perlaza, P; Tomás, X; Pons, F

2015-01-01

To evaluate the impact of the angioscintigrapy of the three phase bone scan as screening method to rule out infection of the hip and knee prosthesis prior to performing the (99m)Tc-HMPAO leukocyte scintigraphy. A total of 120 (70 women, 50 men; mean age 71±11years) with clinical suspicion of hip (n=63) or knee (n=57) infection of the prosthesis and clinical suspicion of infection were evaluated prospectively. All patients underwent three-phase bone scan (angioscintigraphy, vascular and bone phase) and (99m)Tc-HMPAO-labelled white blood cell scintigraphy. Final diagnosis of infection was made by microbiological documentation or clinical follow-up for at least 12months. Eighteen out of 120 patients were diagnosed of infection of hip prosthesis (n=10) or knee prosthesis (n=8). The angioscintigraphy was positive in 15/18 infected cases and in 21/102 of the non-infected cases with a sensitivity of 83%, specificity of 79% and negative predictive value of 97%. Sensitivity and specificity of (99m)Tc-HMPAO leukocyte scintigraphy were 72% and 95%, respectively. If the leukocyte labeled scintigraphies had been used exclusively for patients with positive angioscintigraphy, this would have saved up to 70% of the (99m)Tc-HMPAO leukocyte scintigraphies performed. There were no cases of infection with positive labeled leukocyte scintigraphy and negative angioscintigraphy. Angioscintigraphy (blood flow phase of bone scan) is a useful technique for screening for hip and knee joint prosthesis infection, significantly reducing the need for (99m)Tc-HMPAO leukocyte scintigraphy without affecting the sensitivity of the technique. Copyright © 2014 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

Effect of streptavidin-biotin on endothelial vasoregulation and leukocyte adhesion.

PubMed

Chan, Bernard P; Reichert, William M; Truskey, George A

2004-08-01

The current study examines whether the adhesion promoting arginine-glycine-aspartate-streptavidin mutant (RGD-SA) also affects two important endothelial cell (EC) functions in vitro: vasoregulation and leukocyte adhesion. EC adherent to surfaces via fibronectin (Fn) or Fn plus RGD-SA were subjected to laminar shear flow and media samples were collected over a period of 4h to measure the concentration of nitric oxide (NO), prostacyclin (PGI(2)), and endothelin-1 (ET-1). Western blot analysis was used to quantify the levels of endothelial-derived nitric oxide synthase (eNOS) and cyclooxygenase II (COX II). In a separate set of experiments, fluorescent polymorphonuclear leukocyte (PMN) adhesion to EC was quantified for EC with and without exposure to flow preconditioning. When cell adhesion was supplemented with the SA-biotin system, flow-induced production of NO and PGI(2) increased significantly relative to cells adherent on Fn alone. Previous exposure of EC to shear flow also significantly decreased PMN attachment to SA-biotin supplemented EC, but only after 2h of exposure to shear flow. The observed decrease in PMN-EC adhesion was negated by NG-nitro-L-arginine methyl ester (L-NAME), an antagonist of NO synthesis, but not by indomethacin, an inhibitor to PGI(2) synthesis, indicating the induced effect of PMN-EC interaction is primarily NO-dependent. Results from this study suggest that the use of SA-biotin to supplement EC adhesion encourages vasodilation and PMN adhesion in vitro under physiological shear-stress conditions. We postulate that the presence of SA-biotin more efficiently transmits the shear-stress signal and amplifies the downstream events including the NO and PGI(2) release and leukocyte-EC inhibition. These results may have ramifications for reducing thrombus-induced vascular graft failure.

Association between circulating specific leukocyte types and incident chronic kidney disease: the Atherosclerosis Risk in Communities (ARIC) study.

PubMed

Tian, Niu; Penman, Alan D; Manning, R Davis; Flessner, Michael F; Mawson, Anthony R

2012-01-01

Progressive renal fibrosis is a characteristic of all the diseases that cause renal failure and is invariably accompanied by a prominent leukocyte infiltration in the kidney. The goal of this study was to determine the association between the circulating specific leukocyte types and incident chronic kidney disease (CKD). In a cohort of 10,056 middle-aged white and African American adults, levels of circulating neutrophils, lymphocytes, and monocytes were measured at baseline; blood pressure (BP) and serum creatinine were measured and estimated glomerular filtration rate (eGFR) was calculated at baseline and 3 and 9 years later; and surveillance for first hospitalization or death with CKD was carried out over a mean follow-up of 7.4 years (maximum, 11.9 years). Increased neutrophil levels and decreased lymphocyte levels were significantly associated with greater CKD incidence after adjustment for covariates. African Americans tended to have similar but stronger patterns of association between circulating leukocytes and CKD incidence than whites, although the differences between race groups were not statistically significant. We also found that eGFR and BP were higher at each visit in African Americans than whites between ages 45 and 65. These findings support a potential role for circulating specific leukocytes in the pathogenesis of kidney dysfunction, especially in African Americans, indicating the leukocyte-related renal mechanism of essential hypertension (HT). Copyright © 2012 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

78 FR 16051 - Vehicle/Track Interaction Safety Standards; High-Speed and High Cant Deficiency Operations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-13

...FRA is amending the Track Safety Standards and Passenger Equipment Safety Standards to promote the safe interaction of rail vehicles with the track over which they operate under a variety of conditions at speeds up to 220 m.p.h. The final rule revises standards for track geometry and safety limits for vehicle response to track conditions, enhances vehicle/track qualification procedures, and adds flexibility for permitting high cant deficiency train operations through curves at conventional speeds. The rule accounts for a range of vehicle types that are currently in operation, as well as vehicle types that may likely be used in future high-speed or high cant deficiency rail operations, or both. The rule is based on the results of simulation studies designed to identify track geometry irregularities associated with unsafe wheel/rail forces and accelerations, thorough reviews of vehicle qualification and revenue service test data, and consideration of international practices.

Association between donor leukocyte telomere length and survival after unrelated allogeneic hematopoietic cell transplantation for severe aplastic anemia.

PubMed

Gadalla, Shahinaz M; Wang, Tao; Haagenson, Michael; Spellman, Stephen R; Lee, Stephanie J; Williams, Kirsten M; Wong, Jason Y; De Vivo, Immaculata; Savage, Sharon A

2015-02-10

Telomeres protect chromosome ends and are markers of cellular aging and replicative capacity. To evaluate the association between recipient and donor pretransplant leukocyte telomere length with outcomes after unrelated donor allogeneic hematopoietic cell transplantation (HCT) for patients with severe aplastic anemia. The study included 330 patients (235 acquired, 85 Fanconi anemia, and 10 Diamond-Blackfan anemia) and their unrelated donors who had pre-HCT blood samples and clinical and outcome data available at the Center for International Blood and Marrow Transplant Research. Patients underwent HCT between 1989 and 2007 in 84 centers and were followed-up to March 2013. Recipient and donor pre-HCT leukocyte telomere length classified into long (third tertile) and short (first and second tertiles combined) based on donor telomere length distribution. Overall survival, neutrophil recovery, and acute and chronic graft-vs-host disease, as ascertained by transplant centers through regular patient follow-up. Longer donor leukocyte telomere length was associated with higher survival probability (5-year overall survival, 56%; number at risk, 57; cumulative deaths, 50) than shorter donor leukocyte telomere length (5-year overall survival, 40%; number at risk, 71; cumulative deaths, 128; P = .009). The association remained statistically significant after adjusting for donor age, disease subtype, Karnofsky performance score, graft type, HLA matching, prior aplastic anemia therapy, race/ethnicity, and calendar year of transplant (hazard ratio [HR], 0.61; 95% CI, 0.44-0.86). Similar results were noted in analyses stratified on severe aplastic anemia subtype, recipient age, HLA matching, calendar year of transplant, and conditioning regimen. There was no association between donor telomere length and neutrophil engraftment at 28 days (cumulative incidence, 86% vs 85%; HR, 0.94; 95% CI, 0.73-1.22), acute graft-vs-host disease grades III-IV at 100 days (cumulative incidence

Administration of anesthetic and analgesic prevent the suppression of many leukocyte responses following surgical castration and physical dehorning.

PubMed

Ballou, M A; Sutherland, M A; Brooks, T A; Hulbert, L E; Davis, B L; Cobb, C J

2013-02-15

The objectives of the current research were to determine the physiological effects and responses of many leukocytes following surgical castration and/(or) physical dehorning and the influence of anesthetics and analgesics in 3-month-old calves. Eighty 3-month-old Holstein bull calves were completely randomized to treatments in a 2 × 2 × 2 factorial arrangement with castration, dehorning, and anesthetic/analgesic as the main effects. Peripheral blood samples were collected just before (0) and 0.5, 1.5, 2.5, 4, 6, 24, and 72 h after the respective procedure(s) and analyzed for total leukocyte and differential counts, as well as plasma cortisol and haptoglobin concentrations. Blood from the 0, 0.5 and 24h collections were analyzed for many ex vivo leukocyte responses. Data were analyzed using a repeated measures analysis of variance with the fixed effects of treatment, time, and the interaction of treatment × time. Pre-planned contrasts were performed to determine the effect of (1) management procedure (castration and/(or) dehorning), (2) anesthetic/analgesic, and (3) were the management procedures additive. There were treatment × time interactions (P<0.05) on plasma cortisol and haptoglobin concentrations as well as for total leukocyte and neutrophil concentrations in blood. Castration and dehorning increased cortisol concentrations and the effect of the procedures was additive (P<0.02). Dehorning alone elicited a greater (P<0.05) cortisol response than castration alone. In contrast, the leukocytosis and neutrophilia was greater (P<0.01) among castrated calves. In addition, haptoglobin concentrations at 24h after castration were elevated (P<0.01) in calves that were castrated. Both castration and dehorning suppressed (P=0.04) many leukocyte responses including the secretion of tumor necrosis factor-α when whole blood cultures were stimulated with lipopolysaccharide, surface expression of L-selectin on peripheral blood neutrophils, and the oxidative burst

Social Regulation of Leukocyte Homeostasis: The Role of Glucocorticoid Sensitivity

PubMed Central

Cole, Steve W.

2010-01-01

Recent small-scale genomics analyses suggest that physiologic regulation of pro-inflammatory gene expression by endogenous glucocorticoids may be compromised in individuals who experience chronic social isolation. This could potentially contribute to the elevated prevalence of inflammation-related disease previously observed in social isolates. The present study assessed the relationship between leukocyte distributional sensitivity to glucocorticoid regulation and subjective social isolation in a large population-based sample of older adults. Initial analyses confirmed that circulating neutrophil percentages were elevated, and circulating lymphocyte and monocyte percentages were suppressed, in direct proportion to circulating cortisol levels. However, leukocyte distributional sensitivity to endogenous glucocorticoids was abrogated in individuals reporting either occasional or frequent experiences of subjective social isolation. This finding held in both nonparametric univariate analyses and in multivariate linear models controlling for a variety of biological, social, behavioral, and psychological confounders. The present results suggest that social factors may alter immune cell sensitivity to physiologic regulation by the hypothalamic-pituitary-adrenal axis in ways that could ultimately contribute to the increased physical health risks associated with social isolation. PMID:18394861

Experimental Study of Proton Acceleration from Ultra Intense Laser Matter Interactions

NASA Astrophysics Data System (ADS)

Paudel, Yadab Kumar

This dissertation describes proton and ion acceleration measurements from high intensity (˜ 1019 Wcm-2) laser interactions with thin foil targets. Protons and ions accelerated from the back surface of a target driven by a high intensity laser are detected using solid-state nuclear track detector CR39. A simple digital imaging technique, with an adjustable halogen light source shined on CR39 and use of a digital camera with suitable f-number and exposure time, is used to detect particles tracks. This new technique improves the quality 2D image with vivid track patterns in CR39. Our technique allows us to quickly record and sort CR39 pieces for further analysis. This is followed by detailed quantitative information on the protons and ions. Protons and multicharged ions generated from high-intensity laser interactions with thin foil targets have been studied with a 100 TW laser system. Protons/ions with energies up to 10 MeV are accelerated either from the front or the rear surface of the target material. We have observed for the first time a self-radiograph of the target with a glass stalk holding the target itself in the stacked radiochromic films (RCF) placed behind the target. The self-radiography indicates that the fast ions accelerated backward, in a direction opposite to the laser propagation, are turning around in strong magnetic fields. This unique result is a signature of long-living (ns time scale) magnetic fields in the expanding plasma, which are important in energy transport during the intense laser irradiation and have never been considered in the previous studies. The magnetic fields induced by the main pulse near the absorption point expand rapidly with the backward accelerated protons in the pre-formed plasma. The protons are rotated by these magnetic fields and they are recorded in the RCF, making the self-radiography. Angular profiles of protons and multicharged ions accelerated from the target rear surface have been studied with the subpicosecond

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

Accumulative effects of indoor air pollution exposure on leukocyte telomere length among non-smokers.

PubMed

Lin, Nan; Mu, Xinlin; Wang, Guilian; Ren, Yu'ang; Su, Shu; Li, Zhiwen; Wang, Bin; Tao, Shu

2017-08-01

Indoor air pollution is an important environmental factor that contributes to the burden of various diseases. Long-term exposure to ambient air pollution is associated with telomere shortening. However, the association between chronic indoor air pollution from household fuel combustion and leukocyte telomere length has not been studied. In our study, 137 cancer-free non-smokers were recruited. Their exposure levels to indoor air pollution from 1985 to 2014 were assessed using a face-to-face interview questionnaire, and leukocyte telomere length (LTL) was measured using a monochrome multiplex quantitative PCR method. Accumulative exposure to solid fuel usage for cooking was negatively correlated with LTL. The LTL of residents who were exposed to solid fuel combustion for three decades (LTL = 0.70 ± 0.17) was significantly shorter than that of other populations. In addition, education and occupation were related to both exposure to solid fuel and LTL. Sociodemographic factors may play a mediating role in the correlation between leukocyte telomere length and environmental exposure to indoor air pollution. In conclusion, long-term exposure to indoor air pollution may cause LTL dysfunction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tumor necrosis factor α (TNF-α) receptor-II is required for TNF-α–induced leukocyte-endothelial interaction in vivo

PubMed Central

Chandrasekharan, Unni M.; Siemionow, Maria; Unsal, Murat; Yang, Lin; Poptic, Earl; Bohn, Justin; Ozer, Kagan; Zhou, Zhongmin; Howe, Philip H.; Penn, Marc

2007-01-01

Tumor necrosis factor-α (TNF-α) binds to 2 distinct cell-surface receptors: TNF-α receptor-I (TNFR-I: p55) and TNF-α receptor-II (TNFR-II: p75). TNF-α induces leukocyte adhesion molecules on endothelial cells (ECs), which mediate 3 defined steps of the inflammatory response; namely, leukocyte rolling, firm adhesion, and transmigration. In this study, we have investigated the role of p75 in TNF-α–induced leukocyte adhesion molecules using cultured ECs derived from wild-type (WT), p75-null (p75−/−), or p55-null (p55−/−) mice. We observed that p75 was essential for TNF-α–induced E-selectin, vascular cell adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1) expression. We also investigated the putative role of p75 in inflammation in vivo using an intravital microscopic approach with a mouse cremaster muscle model. TNF-α–stimulated leukocyte rolling, firm adhesion to ECs, and transmigration were dramatically reduced in p75−/− mice. Transplanted WT cremaster in p75−/− mice showed a robust leukocyte rolling and firm adhesion upon TNF-α activation, suggesting that the impairment in EC-leukocyte interaction in p75−/− mice is due to EC dysfunction. These results demonstrate, for the first time, that endothelial p75 is essential for TNF-α–induced leukocyte–endothelial-cell interaction. Our findings may contribute to the identification of novel p75-targeted therapeutic approaches for inflammatory diseases. PMID:17068152

Real-time tracking of respiratory-induced tumor motion by dose-rate regulation

NASA Astrophysics Data System (ADS)

Han-Oh, Yeonju Sarah

We have developed a novel real-time tumor-tracking technology, called Dose-Rate-Regulated Tracking (DRRT), to compensate for tumor motion caused by breathing. Unlike other previously proposed tumor-tracking methods, this new method uses a preprogrammed dynamic multileaf collimator (MLC) sequence in combination with real-time dose-rate control. This new scheme circumvents the technical challenge in MLC-based tumor tracking, that is to control the MLC motion in real time, based on real-time detected tumor motion. The preprogrammed MLC sequence describes the movement of the tumor, as a function of breathing phase, amplitude, or tidal volume. The irregularity of tumor motion during treatment is handled by real-time regulation of the dose rate, which effectively speeds up or slows down the delivery of radiation as needed. This method is based on the fact that all of the parameters in dynamic radiation delivery, including MLC motion, are enslaved to the cumulative dose, which, in turn, can be accelerated or decelerated by varying the dose rate. Because commercially available MLC systems do not allow the MLC delivery sequence to be modified in real time based on the patient's breathing signal, previously proposed tumor-tracking techniques using a MLC cannot be readily implemented in the clinic today. By using a preprogrammed MLC sequence to handle the required motion, the task for real-time control is greatly simplified. We have developed and tested the pre- programmed MLC sequence and the dose-rate regulation algorithm using lung-cancer patients breathing signals. It has been shown that DRRT can track the tumor with an accuracy of less than 2 mm for a latency of the DRRT system of less than 0.35 s. We also have evaluated the usefulness of guided breathing for DRRT. Since DRRT by its very nature can compensate for breathing-period changes, guided breathing was shown to be unnecessary for real-time tracking when using DRRT. Finally, DRRT uses the existing dose-rate control

Intermittent Lagrangian velocities and accelerations in three-dimensional porous medium flow.

PubMed

Holzner, M; Morales, V L; Willmann, M; Dentz, M

2015-07-01

Intermittency of Lagrangian velocity and acceleration is a key to understanding transport in complex systems ranging from fluid turbulence to flow in porous media. High-resolution optical particle tracking in a three-dimensional (3D) porous medium provides detailed 3D information on Lagrangian velocities and accelerations. We find sharp transitions close to pore throats, and low flow variability in the pore bodies, which gives rise to stretched exponential Lagrangian velocity and acceleration distributions characterized by a sharp peak at low velocity, superlinear evolution of particle dispersion, and double-peak behavior in the propagators. The velocity distribution is quantified in terms of pore geometry and flow connectivity, which forms the basis for a continuous-time random-walk model that sheds light on the observed Lagrangian flow and transport behaviors.

Leukocyte Count is Associated with Increased Platelet Reactivity and Diminished Response to Aspirin in Healthy Individuals with a Family History of Coronary Artery Disease

PubMed Central

Faraday, Nauder; Yanek, Lisa R.; Vaidya, Dhananjay; Kral, Brian; Qayyum, Rehan; Herrera-Galeano, J. Enrique; Moy, Taryn F.; Becker, Diane M.; Becker, Lewis C.

2009-01-01

Background Markers of systemic inflammation, including blood leukocyte count, are associated with increased cardiovascular risk, but the mechanisms underlying this association are unclear. Leukocytes may promote platelet reactivity and thrombus formation, providing a basis for increased risk, but a relation between leukocyte count and platelet function has not been studied. Methods We evaluated the relation of blood leukocyte count, C-reactive protein (CRP), and interleukin-6 (IL-6) to platelet aggregation to collagen, ADP and arachidonic acid, and to urinary excretion of 11-dehydro thromboxane B2. Studies were conducted in 1600 individuals (45.0 ± 12.9 years, 42.7% male) at risk for coronary artery disease (CAD) before and after low dose aspirin. Results At baseline, platelet reactivity increased with increasing quartile of leukocyte count (median counts for each quartile were normal) for all measures of platelet function (P<0.0001). These relations were unchanged by aspirin. The relation between leukocyte count and each measure of platelet reactivity remained significant (P<0.05) after multivariable adjustment for CRP, IL-6, cardiac risk factors, hematologic variables, and platelet thromboxane production. CRP and IL-6 were independently associated with few measures of platelet reactivity. Conclusions Increasing quartile of leukocyte count, even within the normal range, is associated with increasing platelet reactivity in individuals at risk for CAD. This relationship is not altered by aspirin and is independent of inflammatory markers and platelet thromboxane production. Additional studies are needed to determine the mechanism(s) for this association and therapies to reduce cardiovascular risk in patients with elevated leukocyte counts. PMID:19185906

TNF{alpha} release from peripheral blood leukocytes depends on a CRM1-mediated nuclear export

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miskolci, Veronika; Department of Pediatrics, Feinstein Institute for Medical Research at the North Shore-Long Island Jewish Health System, New Hyde Park, NY 11040; Ghosh, Chandra C.

2006-12-15

Tumor necrosis factor-{alpha} (TNF{alpha}) is a potent pro-inflammatory cytokine that plays a major role in the pathogenesis of acute and chronic inflammatory disorders such as septic shock and arthritis, respectively. Leukocytes stimulated with inflammatory signals such as lipopolysaccharide (LPS) are the predominant producers of TNF{alpha}, and thus control of TNF{alpha} release from stimulated leukocytes represents a potential therapeutic target. Here, we report that leptomycin B (LMB), a specific inhibitor of CRM1-dependent nuclear protein export, inhibits TNF{alpha} release from LPS-stimulated human peripheral blood neutrophils and mononuclear cells. In addition, immunofluorescence confocal microscopy and immunoblotting analysis indicate that TNF{alpha} is localized inmore » the nucleus of human neutrophils and mononuclear cells. This study demonstrates that the cellular release of TNF{alpha} from stimulated leukocytes is mediated by the CRM1-dependent nuclear export mechanism. Inhibition of CRM1-dependent cellular release of TNF{alpha} could thus provide a novel therapeutic approach for disorders involving excessive TNF{alpha} release.« less

Kinetic Modeling of Next-Generation High-Energy, High-Intensity Laser-Ion Accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Albright, Brian James; Yin, Lin; Stark, David James

One of the long-standing problems in the community is the question of how we can model “next-generation” laser-ion acceleration in a computationally tractable way. A new particle tracking capability in the LANL VPIC kinetic plasma modeling code has enabled us to solve this long-standing problem

The effect of three surface conditions, speed and running experience on vertical acceleration of the tibia during running.

PubMed

Boey, Hannelore; Aeles, Jeroen; Schütte, Kurt; Vanwanseele, Benedicte

2017-06-01

Research has focused on parameters that are associated with injury risk, e.g. vertical acceleration. These parameters can be influenced by running on different surfaces or at different running speeds, but the relationship between them is not completely clear. Understanding the relationship may result in training guidelines to reduce the injury risk. In this study, thirty-five participants with three different levels of running experience were recruited. Participants ran on three different surfaces (concrete, synthetic running track, and woodchip trail) at two different running speeds: a self-selected comfortable speed and a fixed speed of 3.06 m/s. Vertical acceleration of the lower leg was measured with an accelerometer. The vertical acceleration was significantly lower during running on the woodchip trail in comparison with the synthetic running track and the concrete, and significantly lower during running at lower speed in comparison with during running at higher speed on all surfaces. No significant differences in vertical acceleration were found between the three groups of runners at fixed speed. Higher self-selected speed due to higher performance level also did not result in higher vertical acceleration. These results may show that running on a woodchip trail and slowing down could reduce the injury risk at the tibia.

Matrix Metalloproteinase-3 (MMP-3) Is an Endogenous Activator of the MMP-9 Secreted by Placental Leukocytes: Implication in Human Labor.

PubMed

Flores-Pliego, Arturo; Espejel-Nuñez, Aurora; Castillo-Castrejon, Marisol; Meraz-Cruz, Noemi; Beltran-Montoya, Jorge; Zaga-Clavellina, Veronica; Nava-Salazar, Sonia; Sanchez-Martinez, Maribel; Vadillo-Ortega, Felipe; Estrada-Gutierrez, Guadalupe

2015-01-01

The activity of matrix degrading enzymes plays a leading role in the rupture of the fetal membranes under normal and pathological human labor, and matrix metalloproteinase-9 (MMP-9) it is considered a biomarker of this event. To gain further insight into local MMP-9 origin and activation, in this study we analyzed the contribution of human placental leukocytes to MMP-9 secretion and explored the local mechanisms of the pro-enzyme activation. Placental blood leukocytes were obtained from women at term gestation without labor and maintained in culture up to 72 h. MMP-9 activity in the culture supernatants was determined by zymography and using a specific substrate. The presence of a potential pro-MMP-9 activator in the culture supernatants was monitored using a recombinant biotin-labeled human pro-MMP-9. To characterize the endogenous pro-MMP-9 activator, MMP-1, -3, -7 and -9 were measured by multiplex assay in the supernatants, and an inhibition assay of MMP-9 activation was performed using an anti-human MMP-3 and a specific MMP-3 inhibitor. Finally, production of MMP-9 and MMP-3 in placental leukocytes obtained from term pregnancies with and without labor was assessed by immunofluorescence. Placental leukocytes spontaneously secreted pro-MMP-9 after 24 h of culture, increasing significantly at 48 h (P≤0.05), when the active form of MMP-9 was detected. Culture supernatants activated the recombinant pro-MMP-9 showing that placental leukocytes secrete the activator. A significant increase in MMP-3 secretion by placental leukocytes was observed since 48 h in culture (P≤0.05) and up to 72 h (P≤0.001), when concentration reached its maximum value. Specific activity of MMP-9 decreased significantly (P≤0.005) when an anti-MMP-3 antibody or a specific MMP-3 inhibitor were added to the culture media. Placental leukocytes from term labor produced more MMP-9 and MMP-3 compared to term non-labor cells. In this work we confirm that placental leukocytes from human term

Correlation of MLH1 and MGMT methylation levels between peripheral blood leukocytes and colorectal tissue DNA samples in colorectal cancer patients.

PubMed

Li, Xia; Wang, Yibaina; Zhang, Zuoming; Yao, Xiaoping; Ge, Jie; Zhao, Yashuang

2013-11-01

CpG island methylation in the promoter regions of the DNA mismatch repair gene mutator L homologue 1 ( MLH1 ) and DNA repair gene O 6 -methylguanine-DNA methyltransferase ( MGMT ) genes has been shown to occur in the leukocytes of peripheral blood and colorectal tissue. However, it is unclear whether the methylation levels in the blood leukocytes and colorectal tissue are correlated. The present study analyzed and compared the levels of MGMT and MLH1 gene methylation in the leukocytes of peripheral blood and colorectal tissues obtained from patients with colorectal cancer (CRC). The methylation levels of MGMT and MLH1 were examined using methylation-sensitive high-resolution melting (MS-HRM) analysis. A total of 44 patients with CRC were selected based on the MLH1 and MGMT gene methylation levels in the leukocytes of the peripheral blood. Corresponding colorectal tumor and normal tissues were obtained from each patient and the DNA methylation levels were determined. The correlation coefficients were evaluated using Spearman's rank test. Agreement was determined by generalized κ-statistics. Spearman's rank correlation coefficients (r) for the methylation levels of the MGMT and MLH1 genes in the leukocytes of the peripheral blood and normal colorectal tissue were 0.475 and 0.362, respectively (P=0.001 and 0.016, respectively). The agreement of the MGMT and MLH1 gene methylation levels in the leukocytes of the peripheral blood and normal colorectal tissue were graded as fair and poor (κ=0.299 and 0.126, respectively). The methylation levels of MGMT and MLH1 were moderately and weakly correlated between the patient-matched leukocytes and the normal colorectal tissue, respectively. Blood-derived DNA methylation measurements may not always represent the levels of normal colorectal tissue methylation.

A Study of Running Safety and Ride Comfort of Floating Tracks for High-Speed Train

NASA Astrophysics Data System (ADS)

Watanabe, Tsutomu; Sogabe, Masamichi; Yamazaki, Takayuki

In order to reduce train-induced vibration, many floating tracks have been used, however, for only low-speed trains because we are not sure whether riding comfort and running safety can be maintained on floating tracks for high speed train. The authors, in this study, carried out an analysis of dynamic response and running quality of various floating tracks for high-speed train like Shinkansen. We used a simulation program, DIASTARS for the analysis. In this program, the Shinkansen vehicle is represented by a model of three dimensions consisting of a body, two trucks, and four wheelsets connected to each other with springs and dampers. The floating tracks were modeled by three-dimensional finite element method. In this study, the wheel load fluctuation and vehicle body accelerations were investigated by a dynamic interaction analysis between the vehicle and track with the train speed as parameters.

Role of awareness in head-neck acceleration in low velocity rear-end impacts.

PubMed

Kumar, S; Narayan, Y; Amell, T

2000-03-01

Fourteen normal healthy seated and restrained young adults were delivered rear-end impacts of four intensities of acceleration. The chair was delivered a regulated and controlled pneumatic blow using a 30 cm cylinder to cause an acceleration of 0.5, 0.9, 1.1 and 1.4g. The accelerated chair was stopped suddenly by impacting the stopper at the other end of the 2 m long friction reduced track. In one set of trials, subjects were informed about the impending impact and in the other they were blindfolded and provided with loud auditory input to eliminate cues of the impact. The accelerations of the chair, shoulder and head of the participating subjects were measured triaxially and compared between levels of acceleration and expectation. The multiple analyses of variance revealed that the peak acceleration was significantly affected by the gender (P < 0.01), intensity of impact (P < 0.001), and expectation (P < 0.0001). The accelerations were significantly different in different axes (P < 0.001). A significant two-way interaction between acceleration and expectation (P < 0.03), and expectation and axes of acceleration (P < 0.02) would imply that awareness of the impending impact serves to significantly reduce the level of accelerations of head and neck.

Alternatives to an extended Kalman Filter for target image tracking

NASA Astrophysics Data System (ADS)

Leuthauser, P. R.

1981-12-01

Four alternative filters are compared to an extended Kalman filter (EKF) algorithm for tracking a distributed (elliptical) source target in a closed loop tracking problem, using outputs from a forward looking (FLIR) sensor as measurements. These were (1) an EKF with (second order) bias correction term, (2) a constant gain EKF, (3) a constant gain EKF with bias correction term, and (4) a statistically linearized filter. Estimates are made of both actual target motion and of apparent motion due to atmospheric jitter. These alternative designs are considered specifically to address some of the significant biases exhibited by an EKF due to initial acquisition difficulties, unmodelled maneuvering by the target, low signal-to-noise ratio, and real world conditions varying significantly from those assumed in the filter design (robustness). Filter performance was determined with a Monte Carlo study under both ideal and non ideal conditions for tracking targets on a constant velocity cross range path, and during constant acceleration turns of 5G, 10G, and 20G.

Association between levels of C-reactive protein and leukocytes and cancer: Three repeated measurements in the Swedish AMORIS study

PubMed Central

Van Hemelrijck, Mieke; Holmberg, Lars; Garmo, Hans; Hammar, Niklas; Walldius, Göran; Binda, Elisa; Lambe, Mats; Jungner, Ingmar

2011-01-01

Objective To study levels of C-reactive protein (CRP) and leukocytes, as inflammatory markers, in the context of cancer risk. Methods From the Apolipoprotein MOrtality RISk (AMORIS) study, we selected 102,749 persons with one measurement and 9,273 persons with three repeated measurements of CRP and leukocytes. Multivariate Cox proportional hazards regression was applied to categories of CRP (<10, 10-15, 15-25, 25-50, >50 g/L) and quartiles of leukocytes. An Inflammation-based Predictive Score (IPS) indicated whether someone had CRP levels >10mg/L combined with leukocytes >10×109/L. Reverse causality was assessed by excluding those with <3, 5, or 7 years of follow-up. To analyze repeated measurements of CRP and leukocytes the repeated IPS (IPSr) was calculated by adding the IPS of each measurement. Results In the cohort with one measurement, there was a positive trend between CRP and cancer, with the lowest category being the reference: 0.99 (0.92-1.06), 1.28 (1.11-1.47), 1.27 (1.09-1.49), 1.22 (1.01-1.48) for the 2nd to 5th categories, respectively. This association disappeared when excluding those with follow-up <3, 5 or 7 years. The association between leukocytes and cancer was slightly stronger. In the cohort with repeated measurements the IPSr was strongly associated with cancer risk: 1.87 (1.33-2.63), 1.51 (0.56-4.06), 4.46 (1.43-13.87) for IPSr =1, 2, and 3, compared to IPSr =0. The association remained after excluding those with follow-up <1 year. Conclusions and impact Our large prospective cohort study adds evidence for a link between inflammatory markers and cancer risk by using repeated measurements and ascertaining reverse causality. PMID:21297038

Leukocyte changes across menstruation, ovulation, and mid-luteal phase and association with sex hormone variation.

PubMed

Nowak, Judyta; Borkowska, Barbara; Pawlowski, Boguslaw

2016-09-10

Total leukocyte count (white blood cells-WBC) and the count of each subpopulation vary across the menstrual cycle, but results of studies examining the time and direction of these changes are inconsistent and methodologically flawed. Besides, no previous study focused on leukocyte count on the day of ovulation. Blood samples were obtained from 37 healthy and regularly cycling women aged 19.8-36.1 years. Samples were taken three times: during menstruation (M), ovulation (O), and in the mid-luteal phase (ML). WBC, neutrophils, lymphocytes, mixed cells, progesterone (P,) and estradiol (E) were measured in each of the three target phases of the cycle. Compared to menstruation, WBC (P = 0.002) and neutrophils (P < 0.001) increased around ovulation and remained stable in the mid-luteal phase, whereas lymphocyte and mixed cell counts did not change throughout the menstrual cycle. There were some correlations of sex hormone variation with leukocyte changes between M and O (positive for E and WBC, negative for P and WBC and for P and neutrophil count; P < 0.05), but not between O and ML. Peripheral leukocyte changes taking place in the second half of the cycle are already observable on the day of ovulation and they are associated with sex hormone variation. We speculate that these changes may lead to increased immune protection against pathogens at a time when fertilization and implantation typically occur. Am. J. Hum. Biol. 28:721-728, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Studies on the Mechanism of Endogenous Pyrogen Production II. Role of Cell Products in the Regulation of Pyrogen Release from Blood Leukocytes

PubMed Central

Bodel, Phyllis

1974-01-01

Some characteristics of the process by which endogenous pyrogen (EP), the mediator of fever, is released from cells were examined by using human blood leukocytes incubated in vitro. Studies were designed to examine a possible role for leukocyte products, including EP, in the induction, augmentation, or suppression of pyrogen release by blood leukocytes. Products of stimulated leukocytes, including a partially purified preparation of EP, did not induce significant activation of nonstimulated cells. Also, no evidence was obtained that stimulated cell products either augment or inhibit pyrogen production by other stimulated cells. A feedback control of EP production was thus not observed. A crude preparation of EP, containing other products of activated cells, maintained its pyrogenicity when incubated at pH 7.4 but not at pH 5.0. These studies thus provide no support for hypothesized control mechanisms regulating production of EP by blood leukocytes. By contrast, local inactivation of EP at inflammatory sites may modify the amount of EP entering the blood, and hence fever. PMID:4426696

On the safety of ITER accelerators.

PubMed

Li, Ge

2013-01-01

Three 1 MV/40A accelerators in heating neutral beams (HNB) are on track to be implemented in the International Thermonuclear Experimental Reactor (ITER). ITER may produce 500 MWt of power by 2026 and may serve as a green energy roadmap for the world. They will generate -1 MV 1 h long-pulse ion beams to be neutralised for plasma heating. Due to frequently occurring vacuum sparking in the accelerators, the snubbers are used to limit the fault arc current to improve ITER safety. However, recent analyses of its reference design have raised concerns. General nonlinear transformer theory is developed for the snubber to unify the former snubbers' different design models with a clear mechanism. Satisfactory agreement between theory and tests indicates that scaling up to a 1 MV voltage may be possible. These results confirm the nonlinear process behind transformer theory and map out a reliable snubber design for a safer ITER.

On the safety of ITER accelerators

PubMed Central

Li, Ge

2013-01-01

Three 1 MV/40A accelerators in heating neutral beams (HNB) are on track to be implemented in the International Thermonuclear Experimental Reactor (ITER). ITER may produce 500 MWt of power by 2026 and may serve as a green energy roadmap for the world. They will generate −1 MV 1 h long-pulse ion beams to be neutralised for plasma heating. Due to frequently occurring vacuum sparking in the accelerators, the snubbers are used to limit the fault arc current to improve ITER safety. However, recent analyses of its reference design have raised concerns. General nonlinear transformer theory is developed for the snubber to unify the former snubbers' different design models with a clear mechanism. Satisfactory agreement between theory and tests indicates that scaling up to a 1 MV voltage may be possible. These results confirm the nonlinear process behind transformer theory and map out a reliable snubber design for a safer ITER. PMID:24008267

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

PubMed

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.

Pulmonary uptake in Indium-111 leukocyte imaging: clinical significance in patients with suspected occult infections

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cook, P.S.; Datz, F.L.; Disbro, M.A.

1984-02-01

A retrospective review was undertaken to evaluate the frequency and significance of pulmonary activity noted on 306 indium-111 leukocyte studies involving 232 patients with suspected occult infections. Forty-eight studies showed pulmonary activity in one of two patterns of uptake, focal or diffuse. Fourteen of 27 studies (52%) with focal uptake and two of 21 studies (10%) with diffuse uptake were associated with infectious processes. Lung uptake of indium-111-labeled leukocytes was a poor predictor of pulmonary infection in patients studied for occult infection, although the focal pattern was more likely than the diffuse pattern to be associated with infection.

Dose calculation and verification of the Vero gimbal tracking treatment delivery

NASA Astrophysics Data System (ADS)

Prasetio, H.; Wölfelschneider, J.; Ziegler, M.; Serpa, M.; Witulla, B.; Bert, C.

2018-02-01

The Vero linear accelerator delivers dynamic tumor tracking (DTT) treatment using a gimbal motion. However, the availability of treatment planning systems (TPS) to simulate DTT is limited. This study aims to implement and verify the gimbal tracking beam geometry in the dose calculation. Gimbal tracking was implemented by rotating the reference CT outside the TPS according to the ring, gantry, and gimbal tracking position obtained from the tracking log file. The dose was calculated using these rotated CTs. The geometric accuracy was verified by comparing calculated and measured film response using a ball bearing phantom. The dose was verified by comparing calculated 2D dose distributions and film measurements in a ball bearing and a homogeneous phantom using a gamma criterion of 2%/2 mm. The effect of implementing the gimbal tracking beam geometry in a 3D patient data dose calculation was evaluated using dose volume histograms (DVH). Geometrically, the gimbal tracking implementation accuracy was  <0.94 mm. The isodose lines agreed with the film measurement. The largest dose difference of 9.4% was observed at maximum tilt positions with an isocenter and target separation of 17.51 mm. Dosimetrically, gamma passing rates were  >98.4%. The introduction of the gimbal tracking beam geometry in the dose calculation shifted the DVH curves by 0.05%-1.26% for the phantom geometry and by 5.59% for the patient CT dataset. This study successfully demonstrates a method to incorporate the gimbal tracking beam geometry into dose calculations. By combining CT rotation and MU distribution according to the log file, the TPS was able to simulate the Vero tracking treatment dose delivery. The DVH analysis from the gimbal tracking dose calculation revealed changes in the dose distribution during gimbal DTT that are not visible with static dose calculations.

Calibrating acoustic acceleration transmitters for estimating energy use by wild adult Pacific salmon.

PubMed

Wilson, S M; Hinch, S G; Eliason, E J; Farrell, A P; Cooke, S J

2013-03-01

This study is the first to calibrate acceleration transmitters with energy expenditure using a vertebrate model species. We quantified the relationship between acoustic accelerometer output and oxygen consumption across a range of swim speeds and water temperatures for Harrison River adult sockeye salmon (Oncorhynchus nerka). First, we verified that acceleration transmitters with a sampling frequency of 10 Hz could be used as a proxy for movement in sockeye salmon. Using a mixed effects model, we determined that tailbeat frequency and acceleration were positively correlated (p<0.0001), independent of tag ID. Acceleration (p<0.0001) was positively related to swim speed while fork length (p=0.051) was negatively related to swim speed. Oxygen consumption and accelerometer output (p<0.0001) had a positive linear relationship and were temperature dependent (p<0.0001). There were no differences in swim performance (F(2,12)=1.023, p=0.820) or oxygen consumption (F(1,12)=0.054, p=0.332) between tagged and untagged individuals. Five tagged fish were released into the Fraser River estuary and manually tracked. Of the five fish, three were successfully tracked for 1h. The above relationships were used to determine that the average swim speed was 1.25±0.03 body lengths s(-1) and cost of transport was 3.39±0.17 mg O(2) kg(-1)min(-1), averaged across the three detected fish. Acceleration transmitters can be effectively used to remotely evaluate fine-scale behavior and estimate energy consumption of adult Pacific salmon throughout their homeward spawning migration. Copyright © 2012 Elsevier Inc. All rights reserved.

Experimental Validation of Pulse Phase Tracking for X-Ray Pulsar Based

NASA Technical Reports Server (NTRS)

Anderson, Kevin

2012-01-01

Pulsars are a form of variable celestial source that have shown to be usable as aids for autonomous, deep space navigation. Particularly those sources emitting in the X-ray band are ideal for navigation due to smaller detector sizes. In this paper X-ray photons arriving from a pulsar are modeled as a non-homogeneous Poisson process. The method of pulse phase tracking is then investigated as a technique to measure the radial distance traveled by a spacecraft over an observation interval. A maximum-likelihood phase estimator (MLE) is used for the case where the observed frequency signal is constant. For the varying signal frequency case, an algorithm is used in which the observation window is broken up into smaller blocks over which an MLE is used. The outputs of this phase estimation process were then looped through a digital phase-locked loop (DPLL) in order to reduce the errors and produce estimates of the doppler frequency. These phase tracking algorithms were tested both in a computer simulation environment and using the NASA Goddard Space flight Center X-ray Navigation Laboratory Testbed (GXLT). This provided an experimental validation with photons being emitted by a modulated X-ray source and detected by a silicon-drift detector. Models of the Crab pulsar and the pulsar B1821-24 were used in order to generate test scenarios. Three different simulated detector trajectories were used to be tracked by the phase tracking algorithm: a stationary case, one with constant velocity, and one with constant acceleration. All three were performed in one-dimension along the line of sight to the pulsar. The first two had a constant signal frequency and the third had a time varying frequency. All of the constant frequency cases were processed using the MLE, and it was shown that they tracked the initial phase within 0.15% for the simulations and 2.5% in the experiments, based on an average of ten runs. The MLE-DPLL cascade version of the phase tracking algorithm was used in

Command generator tracker based direct model reference adaptive tracking guidance for Mars atmospheric entry

NASA Astrophysics Data System (ADS)

Li, Shuang; Peng, Yuming

2012-01-01

In order to accurately deliver an entry vehicle through the Martian atmosphere to the prescribed parachute deployment point, active Mars entry guidance is essential. This paper addresses the issue of Mars atmospheric entry guidance using the command generator tracker (CGT) based direct model reference adaptive control to reduce the adverse effect of the bounded uncertainties on atmospheric density and aerodynamic coefficients. Firstly, the nominal drag acceleration profile meeting a variety of constraints is planned off-line in the longitudinal plane as the reference model to track. Then, the CGT based direct model reference adaptive controller and the feed-forward compensator are designed to robustly track the aforementioned reference drag acceleration profile and to effectively reduce the downrange error. Afterwards, the heading alignment logic is adopted in the lateral plane to reduce the crossrange error. Finally, the validity of the guidance algorithm proposed in this paper is confirmed by Monte Carlo simulation analysis.

Circulating leukocyte telomere length is highly heritable among families of Arab descent

PubMed Central

2012-01-01

Background Telomere length, an indicator of ageing and longevity, has been correlated with several biomarkers of cardiometabolic disease in both Arab children and adults. It is not known, however, whether or not telomere length is a highly conserved inheritable trait in this homogeneous cohort, where age-related diseases are highly prevalent. As such, the aim of this study was to address the inheritability of telomere length in Saudi families and the impact of cardiometabolic disease biomarkers on telomere length. Methods A total of 119 randomly selected Saudi families (123 adults and 131 children) were included in this cross-sectional study. Anthropometrics were obtained and fasting blood samples were taken for routine analyses of fasting glucose and lipid profile. Leukocyte telomere length was determined using quantitative real time PCR. Results Telomere length was highly heritable as assessed by a parent-offspring regression [h2 = 0.64 (p = 0.0006)]. Telomere length was modestly associated with BMI (R2 0.07; p-value 0.0087), total cholesterol (R2 0.08; p-value 0.0033), and LDL-cholesterol (R2 0.15; p-value 3 x 10-5) after adjustments for gender, age and age within generation. Conclusion The high heritability of telomere length in Arab families, and the associations of telomere length with various cardiometabolic parameters suggest heritable genetic fetal and/or epigenetic influences on the early predisposition of Arab children to age-related diseases and accelerated ageing. PMID:22606980

Circulating leukocyte telomere length is highly heritable among families of Arab descent.

PubMed

Al-Attas, Omar S; Al-Daghri, Nasser M; Alokail, Majed S; Alkharfy, Khalid M; Alfadda, Assim A; McTernan, Philip; Gibson, Greg C; Sabico, Shaun B; Chrousos, George P

2012-05-18

Telomere length, an indicator of ageing and longevity, has been correlated with several biomarkers of cardiometabolic disease in both Arab children and adults. It is not known, however, whether or not telomere length is a highly conserved inheritable trait in this homogeneous cohort, where age-related diseases are highly prevalent. As such, the aim of this study was to address the inheritability of telomere length in Saudi families and the impact of cardiometabolic disease biomarkers on telomere length. A total of 119 randomly selected Saudi families (123 adults and 131 children) were included in this cross-sectional study. Anthropometrics were obtained and fasting blood samples were taken for routine analyses of fasting glucose and lipid profile. Leukocyte telomere length was determined using quantitative real time PCR. Telomere length was highly heritable as assessed by a parent-offspring regression [h2 = 0.64 (p = 0.0006)]. Telomere length was modestly associated with BMI (R(2) 0.07; p-value 0.0087), total cholesterol (R(2) 0.08; p-value 0.0033), and LDL-cholesterol (R(2) 0.15; p-value 3 x 10(-5)) after adjustments for gender, age and age within generation. The high heritability of telomere length in Arab families, and the associations of telomere length with various cardiometabolic parameters suggest heritable genetic fetal and/or epigenetic influences on the early predisposition of Arab children to age-related diseases and accelerated ageing.

Antimicrobial properties of single-donor-derived, platelet-leukocyte fibrin for fistula occlusion: An in vitro study.

PubMed

Wu, Xiuwen; Ren, Jianan; Yuan, Yujie; Luan, Jianfeng; Yao, Genhong; Li, Jieshou

2013-01-01

Fibrin glue is a promising alternative for low-output enterocutaneous fistula closure. Bacterial flora colonizing inside the fistula tract, however, may limit the glue application. Single-donor-derived, platelet-rich materials were hypothesized in this study to have antimicrobial activity against Gram-negative microorganisms. Platelet-leukocyte fibrin (PLF), platelet-rich plasma (PRP), and platelet-poor plasma (PPP) were obtained from healthy volunteers. The amounts of platelet, leukocyte, and complement/antibody were determined. In vitro laboratory susceptibility to PLF and plasmas was determined by the Kirby-Bauer disc-diffusion method. Antimicrobial activity of PLF, PRP, and PPP against three Gram-negative ATCC strains was determined in a bacterial kill assay. Levels of complement and antibody did not significantly differ among PLF, PRP, and PPP (p > 0.05), while platelet and leukocyte counts in platelet-rich biomaterials were significantly higher than those in PPP (p < 0.001). The bactericidal effects produced by PLF and PRP were more pronounced than those by PPP in both qualitative and quantitative aspects. No inhibitory zones against three Gram-negative organisms were observed in the Bioseal®. In conclusion, our homemade PLF, as compared with commercial products, had remarkable antimicrobial activity against Gram-negative bacteria relevant to fistula colonization. The presence of platelets and leukocytes may play an important role in bacterial defense. This is the first study to demonstrate the antibacterial properties of single-unit PLF for fistula closure, presenting a new opportunity for glue sealing.

Oxidative stress and reduced responsiveness of challenged circulating leukocytes following pulmonary instillation of metal-rich particulate matter in rats

PubMed Central

2014-01-01

Welding fume is an exposure that consists of a mixture of metal-rich particulate matter with gases (ozone, carbon monoxide) and/or vapors (VOCs). Data suggests that welders are immune compromised. Given the inability of pulmonary leukocytes to properly respond to a secondary infection in animal models, the question arose whether the dysfunction persisted systemically. Our aim was to evaluate the circulating leukocyte population in terms of cellular activation, presence of oxidative stress, and functionality after a secondary challenge, following welding fume exposure. Rats were intratracheally instilled (ITI) with PBS or 2 mg of welding fume collected from a stainless steel weld. Rats were sacrificed 4 and 24 h post-exposure and whole blood was collected. Whole blood was used for cellular differential counts, RNA isolation with subsequent microarray and Ingenuity Pathway Analysis, and secondary stimulation with LPS utilizing TruCulture technology. In addition, mononuclear cells were isolated 24 h post-exposure to measure oxidative stress by flow cytometry and confocal microscopy. Welding fume exposure had rapid effects on the circulating leukocyte population as identified by relative mRNA expression changes. Instillation of welding fume reduced inflammatory protein production of circulating leukocytes when challenged with the secondary stimulus LPS. The effects were not related to transcription, but were observed in conjunction with oxidative stress. These findings support previous studies of an inadequate pulmonary immune response following a metal-rich exposure and extend those findings showing leukocyte dysfunction occurs systemically. PMID:25123171

Oxidative stress and reduced responsiveness of challenged circulating leukocytes following pulmonary instillation of metal-rich particulate matter in rats.

PubMed

Erdely, Aaron; Antonini, James M; Young, Shih-Houng; Kashon, Michael L; Gu, Ja K; Hulderman, Tracy; Salmen, Rebecca; Meighan, Terence; Roberts, Jenny R; Zeidler-Erdely, Patti C

2014-08-15

Welding fume is an exposure that consists of a mixture of metal-rich particulate matter with gases (ozone, carbon monoxide) and/or vapors (VOCs). Data suggests that welders are immune compromised. Given the inability of pulmonary leukocytes to properly respond to a secondary infection in animal models, the question arose whether the dysfunction persisted systemically. Our aim was to evaluate the circulating leukocyte population in terms of cellular activation, presence of oxidative stress, and functionality after a secondary challenge, following welding fume exposure. Rats were intratracheally instilled (ITI) with PBS or 2 mg of welding fume collected from a stainless steel weld. Rats were sacrificed 4 and 24 h post-exposure and whole blood was collected. Whole blood was used for cellular differential counts, RNA isolation with subsequent microarray and Ingenuity Pathway Analysis, and secondary stimulation with LPS utilizing TruCulture technology. In addition, mononuclear cells were isolated 24 h post-exposure to measure oxidative stress by flow cytometry and confocal microscopy. Welding fume exposure had rapid effects on the circulating leukocyte population as identified by relative mRNA expression changes. Instillation of welding fume reduced inflammatory protein production of circulating leukocytes when challenged with the secondary stimulus LPS. The effects were not related to transcription, but were observed in conjunction with oxidative stress. These findings support previous studies of an inadequate pulmonary immune response following a metal-rich exposure and extend those findings showing leukocyte dysfunction occurs systemically.

Enhancement in ex vivo phagocytic capacity of peritoneal leukocytes in mice by oral delivery of various lactic-acid-producing bacteria.

PubMed

Lee, Yeonhee; Lee, Taik-Soo

2005-01-01

Lactic-acid-producing bacteria (LABs) are known to have immunomodulating activity. In the current study, various LABs were tested for their immunity-enhancing activity, especially the phagocytic activity of leukocytes. Viable but not heat-killed cells of Weissella kimchii strain PL9001, Lactobacillus fermentum strain PL9005, and L. plantarum strain PL9011 significantly increased the ex vivo phagocytic capacity of mouse peritoneal leukocytes to ingest fluorescein isothiocyanate (FITC)-labeled Escherichia coli in a strain-dependent manner. Results of this and previous studies suggest these LABs as candidates for new probiotics. This is the first report of the enhancement of peritoneal leukocyte activity of these species.

Pathophysiological levels of soluble P-selectin mediate adhesion of leukocytes to the endothelium through Mac-1 activation.

PubMed

Woollard, Kevin J; Suhartoyo, Andreas; Harris, Emma E; Eisenhardt, Steffen U; Jackson, Shaun P; Peter, Karlheinz; Dart, Anthony M; Hickey, Michael J; Chin-Dusting, Jaye P F

2008-11-07

Plasma soluble P-selectin (sP-selectin) levels are increased in pathologies associated with atherosclerosis, including peripheral arterial occlusive disease (PAOD). However, the role of sP-selectin in regulating leukocyte-endothelial adhesion is unclear. The aim of this study was to assess the ability of exogenous and endogenous sP-selectin to induce leukocyte responses that promote their adhesion to various forms of endothelium. In flow chamber assays, sP-selectin dose-dependently increased neutrophil adhesion to resting human iliac artery endothelial cells. Similarly, sP-selectin induced neutrophil adhesion to the endothelial surface of murine aortae and human radial venous segments in ex vivo flow chamber experiments. Using intravital microscopy to examine postcapillary venules in the mouse cremaster muscle, in vivo administration of sP-selectin was also found to significantly increase leukocyte rolling and adhesion in unstimulated postcapillary venules. Using a Mac-1-specific antibody and P-selectin knockout mouse, it was demonstrated that this finding was dependent on a contribution of Mac-1 to leukocyte rolling and endothelial P-selectin expression. This was confirmed in an ex vivo perfusion model using viable mouse aorta and human radial vessels. In contrast, with tumor necrosis factor-alpha-activated endothelial cells and intact endothelium, where neutrophil adhesion was already elevated, sP-selectin failed to further increase adhesion. Plasma samples from PAOD patients containing pathologically elevated concentrations of sP-selectin also increased neutrophil adhesion to the endothelium in a sP-selectin-dependent manner, as demonstrated by immunodepletion of sP-selectin. These studies demonstrate that raised plasma sP-selectin may influence the early progression of vascular disease by promoting leukocyte adhesion to the endothelium in PAOD, through Mac-1-mediated rolling and dependent on endothelial P-selectin expression.

Higher circulating leukocytes in women with PCOS is reversed by aerobic exercise.

PubMed

Covington, Jeffrey D; Tam, Charmaine S; Pasarica, Magdalena; Redman, Leanne M

2016-05-01

Polycystic ovary syndrome (PCOS) is characterized by insulin resistance, elevated circulating leukocytes, and hypothesized to have higher adipose tissue inflammation. Aerobic exercise reduces circulating leukocytes and improves insulin sensitivity in obese individuals, but the effect of exercise on inflammation in PCOS is not known. We investigated circulating leukocytes, insulin sensitivity by euglycemic-hyperinsulinemic clamp, serum pro- and anti-inflammatory markers (hsCRP, TNF-α, total and high molecular weight adiponectin), and abdominal subcutaneous adipose tissue (SAT) gene expression of proinflammatory markers in 8 PCOS women and 8 obese control females matched for BMI. Additionally, in a prospective study, the 8 women with PCOS underwent a 16-week aerobic exercise regimen with the same measures performed post-intervention. Compared to controls, white blood cell counts (WBC) were 30% higher (p = 0.04) and circulating total adiponectin levels were 150% lower (p = 0.03) in women with PCOS at baseline/pre-exercise conditions. SAT gene expression of macrophage migration inhibitory factor (MIF, p < 0.01) and interleukin-6 (IL-6, p < 0.05) were also lower in women with PCOS. In response to 16 weeks of aerobic exercise, insulin sensitivity improved (p < 0.01) and WBC counts decreased (p = 0.02). The exercise-induced change in WBC and circulating neutrophils correlated inversely with changes in glucose disposal rate (r = -0.73, p = 0.03; and r = -0.82, p = 0.01, respectively). Aerobic exercise reduced serum leptin (p < 0.05) after 4 weeks, trended to reduce the ratio of leptin-to-high molecular weight adiponectin (p < 0.1) by the 8th week, and significantly increased serum dehydroepiandrosterone sulfate (DHEA-S, p < 0.001) after 16 weeks. In conclusion, women with PCOS have higher circulating leukocytes compared to controls, which can be reversed by aerobic exercise and is associated with improvements in insulin sensitivity. Copyright �

On the dynamics of jellyfish locomotion via 3D particle tracking velocimetry

NASA Astrophysics Data System (ADS)

Piper, Matthew; Kim, Jin-Tae; Chamorro, Leonardo P.

2016-11-01

The dynamics of jellyfish (Aurelia aurita) locomotion is experimentally studied via 3D particle tracking velocimetry. 3D locations of the bell tip are tracked over 1.5 cycles to describe the jellyfish path. Multiple positions of the jellyfish bell margin are initially tracked in 2D from four independent planes and individually projected in 3D based on the jellyfish path and geometrical properties of the setup. A cubic spline interpolation and the exponentially weighted moving average are used to estimate derived quantities, including velocity and acceleration of the jellyfish locomotion. We will discuss distinctive features of the jellyfish 3D motion at various swimming phases, and will provide insight on the 3D contraction and relaxation in terms of the locomotion, the steadiness of the bell margin eccentricity, and local Reynolds number based on the instantaneous mean diameter of the bell.

Differential adipokine receptor expression on circulating leukocyte subsets in lean and obese children.

PubMed

Keustermans, Genoveva; van der Heijden, Laila B; Boer, Berlinda; Scholman, Rianne; Nuboer, Roos; Pasterkamp, Gerard; Prakken, Berent; de Jager, Wilco; Kalkhoven, Eric; Janse, Arieke J; Schipper, Henk S

2017-01-01

Childhood obesity prevalence has increased worldwide and is an important risk factor for type 2 diabetes (T2D) and cardiovascular disease (CVD). The production of inflammatory adipokines by obese adipose tissue contributes to the development of T2D and CVD. While levels of circulating adipokines such as adiponectin and leptin have been established in obese children and adults, the expression of adiponectin and leptin receptors on circulating immune cells can modulate adipokine signalling, but has not been studied so far. Here, we aim to establish the expression of adiponectin and leptin receptors on circulating immune cells in obese children pre and post-lifestyle intervention compared to normal weight control children. 13 obese children before and after a 1-year lifestyle intervention were compared with an age and sex-matched normal weight control group of 15 children. Next to routine clinical and biochemical parameters, circulating adipokines were measured, and flow cytometric analysis of adiponectin receptor 1 and 2 (AdipoR1, AdipoR2) and leptin receptor expression on peripheral blood mononuclear cell subsets was performed. Obese children exhibited typical clinical and biochemical characteristics compared to controls, including a higher BMI-SD, blood pressure and circulating leptin levels, combined with a lower insulin sensitivity index (QUICKI). The 1-year lifestyle intervention resulted in stabilization of their BMI-SD. Overall, circulating leukocyte subsets showed distinct adipokine receptor expression profiles. While monocytes expressed high levels of all adipokine receptors, NK and iNKT cells predominantly expressed AdipoR2, and B-lymphocytes and CD4+ and CD8+ T-lymphocyte subsets expressed AdipoR2 as well as leptin receptor. Strikingly though, leukocyte subset numbers and adipokine receptor expression profiles were largely similar in obese children and controls. Obese children showed higher naïve B-cell numbers, and pre-intervention also higher numbers of

Automatic Tracking Algorithm in Coaxial Near-Infrared Laser Ablation Endoscope for Fetus Surgery

NASA Astrophysics Data System (ADS)

Hu, Yan; Yamanaka, Noriaki; Masamune, Ken

2014-07-01

This article reports a stable vessel object tracking method for the treatment of twin-to-twin transfusion syndrome based on our previous 2 DOF endoscope. During the treatment of laser coagulation, it is necessary to focus on the exact position of the target object, however it moves by the mother's respiratory motion and still remains a challenge to obtain and track the position precisely. In this article, an algorithm which uses features from accelerated segment test (FAST) to extract the features and optical flow as the object tracking method, is proposed to deal with above problem. Further, we experimentally simulate the movement due to the mother's respiration, and the results of position errors and similarity verify the effectiveness of the proposed tracking algorithm for laser ablation endoscopy in-vitro and under water considering two influential factors. At average, the errors are about 10 pixels and the similarity over 0.92 are obtained in the experiments.

Navigating Uncharted Waters: An Accelerated Content-Based English for Academic Purposes Program

ERIC Educational Resources Information Center

Hernandez, Kelly; Thomas, Michelle; Schuemann, Cynthia

2012-01-01

In 2008, Miami Dade College received a $1.9 million Title V grant from the US Department of Education to develop an Accelerated Content-Based English for Academic Purposes (EAP) track called Project ACE for ESL students. The ACE curriculum is anchored by the principles of flexibility, contextualization, and faculty buy-in--critical matters given…

The Leukocyte Culture Method in the Diagnosis of Free-martinism

PubMed Central

Kanagawa, H.; Basrur, Parvathi K.

1968-01-01

The clinical application and reliability of the leukocyte culture method for the diagnosis of freemartinism were examined and the length of time that blood samples could be held at room temperature and in the refrigerator prior to culturing, was investigated. The chromosome findings by the leukocyte culture method in 14 freemartins and 9 non-freemartin females belonging to heterosexual twins or triplets revealed that XX-XY cell chimerism exists only in the former, whereas the latter were exclusively of normal female complement. The mitotic index in bovine blood after preservation for varying periods was studied on samples from two animals. Blood samples from these two animals stored at 5°C for 6 hours in a refrigerator showed the mitotic index to be 3.8 and 5.3 per cent which gradually decreased in samples stored for longer than 12 hours. After 72 hours, a very rapid decrease in mitotic index occurred in both cases, reaching zero in samples stored for 96 and 108 hours. Samples kept at room temperature followed a similar pattern as under refrigeration but with slightly lower values throughout. ImagesFig. 1.Fig. 2. PMID:4234791

Detecting chaos in particle accelerators through the frequency map analysis method.

PubMed

Papaphilippou, Yannis

2014-06-01

The motion of beams in particle accelerators is dominated by a plethora of non-linear effects, which can enhance chaotic motion and limit their performance. The application of advanced non-linear dynamics methods for detecting and correcting these effects and thereby increasing the region of beam stability plays an essential role during the accelerator design phase but also their operation. After describing the nature of non-linear effects and their impact on performance parameters of different particle accelerator categories, the theory of non-linear particle motion is outlined. The recent developments on the methods employed for the analysis of chaotic beam motion are detailed. In particular, the ability of the frequency map analysis method to detect chaotic motion and guide the correction of non-linear effects is demonstrated in particle tracking simulations but also experimental data.