Liquid Acquisition Device Design Sensitivity Study

NASA Technical Reports Server (NTRS)

VanDyke, M. K.; Hastings, L. J.

2012-01-01

In-space propulsion often necessitates the use of a capillary liquid acquisition device (LAD) to assure that gas-free liquid propellant is available to support engine restarts in microgravity. If a capillary screen-channel device is chosen, then the designer must determine the appropriate combination screen mesh and channel geometry. A screen mesh selection which results in the smallest LAD width when compared to any other screen candidate (for a constant length) is desirable; however, no best screen exists for all LAD design requirements. Flow rate, percent fill, and acceleration are the most influential drivers for determining screen widths. Increased flow rates and reduced percent fills increase the through-the-screen flow pressure losses, which drive the LAD to increased widths regardless of screen choice. Similarly, increased acceleration levels and corresponding liquid head pressures drive the screen mesh selection toward a higher bubble point (liquid retention capability). After ruling out some screens on the basis of acceleration requirements alone, candidates can be identified by examining screens with small flow-loss-to-bubble point ratios for a given condition (i.e., comparing screens at certain flow rates and fill levels). Within the same flow rate and fill level, the screen constants inertia resistance coefficient, void fraction, screen pore or opening diameter, and bubble point can become the driving forces in identifying the smaller flow-loss-to-bubble point ratios.

Logical analysis of diffuse large B-cell lymphomas.

PubMed

Alexe, G; Alexe, S; Axelrod, D E; Hammer, P L; Weissmann, D

2005-07-01

The goal of this study is to re-examine the oligonucleotide microarray dataset of Shipp et al., which contains the intensity levels of 6817 genes of 58 patients with diffuse large B-cell lymphoma (DLBCL) and 19 with follicular lymphoma (FL), by means of the combinatorics, optimisation, and logic-based methodology of logical analysis of data (LAD). The motivations for this new analysis included the previously demonstrated capabilities of LAD and its expected potential (1) to identify different informative genes than those discovered by conventional statistical methods, (2) to identify combinations of gene expression levels capable of characterizing different types of lymphoma, and (3) to assemble collections of such combinations that if considered jointly are capable of accurately distinguishing different types of lymphoma. The central concept of LAD is a pattern or combinatorial biomarker, a concept that resembles a rule as used in decision tree methods. LAD is able to exhaustively generate the collection of all those patterns which satisfy certain quality constraints, through a systematic combinatorial process guided by clear optimization criteria. Then, based on a set covering approach, LAD aggregates the collection of patterns into classification models. In addition, LAD is able to use the information provided by large collections of patterns in order to extract subsets of variables, which collectively are able to distinguish between different types of disease. For the differential diagnosis of DLBCL versus FL, a model based on eight significant genes is constructed and shown to have a sensitivity of 94.7% and a specificity of 100% on the test set. For the prognosis of good versus poor outcome among the DLBCL patients, a model is constructed on another set consisting also of eight significant genes, and shown to have a sensitivity of 87.5% and a specificity of 90% on the test set. The genes selected by LAD also work well as a basis for other kinds of statistical analysis, indicating their robustness. These two models exhibit accuracies that compare favorably to those in the original study. In addition, the current study also provides a ranking by importance of the genes in the selected significant subsets as well as a library of dozens of combinatorial biomarkers (i.e. pairs or triplets of genes) that can serve as a source of mathematically generated, statistically significant research hypotheses in need of biological explanation.

The LOFT ground segment

NASA Astrophysics Data System (ADS)

Bozzo, E.; Antonelli, A.; Argan, A.; Barret, D.; Binko, Pavel; Brandt, S.; Cavazzuti, E.; Courvoisier, T.; den Herder, J. W.; Feroci, M.; Ferrigno, C.; Giommi, P.; Götz, D.; Guy, L.; Hernanz, M.; in't Zand, J. J. M.; Klochkov, D.; Kuulkers, Erik; Motch, C.; Lumb, D.; Papitto, A.; Pittori, Carlotta; Rohlfs, R.; Santangelo, A.; Schmid, C.; Schwope, A. D.; Smith, P. J.; Webb, N. A.; Wilms, J.; Zane, S.

2014-07-01

LOFT, the Large Observatory For X-ray Timing, was one of the ESA M3 mission candidates that completed their assessment phase at the end of 2013. LOFT is equipped with two instruments, the Large Area Detector (LAD) and the Wide Field Monitor (WFM). The LAD performs pointed observations of several targets per orbit (~90 minutes), providing roughly ~80 GB of proprietary data per day (the proprietary period will be 12 months). The WFM continuously monitors about 1/3 of the sky at a time and provides data for about ~100 sources a day, resulting in a total of ~20 GB of additional telemetry. The LOFT Burst alert System additionally identifies on-board bright impulsive events (e.g., Gamma-ray Bursts, GRBs) and broadcasts the corresponding position and trigger time to the ground using a dedicated system of ~15 VHF receivers. All WFM data are planned to be made public immediately. In this contribution we summarize the planned organization of the LOFT ground segment (GS), as established in the mission Yellow Book1. We describe the expected GS contributions from ESA and the LOFT consortium. A review is provided of the planned LOFT data products and the details of the data flow, archiving and distribution. Despite LOFT was not selected for launch within the M3 call, its long assessment phase ( >2 years) led to a very solid mission design and an efficient planning of its ground operations.

Light-assisted drying (LAD) of small volume biologics: a comparison of two IR light sources

NASA Astrophysics Data System (ADS)

Young, Madison A.; Van Vorst, Matthew; Elliott, Gloria D.; Trammell, Susan R.

2016-03-01

Protein therapeutics have been developed to treat diseases ranging from arthritis and psoriasis to cancer. A challenge in the development of protein-based drugs is maintaining the protein in the folded state during processing and storage. We are developing a novel processing method, light-assisted drying (LAD), to dehydrate proteins suspended in a sugar (trehalose) solution for storage at supra-zero temperatures. Our technique selectively heats the water in small volume samples using near-IR light to speed dehydration which prevents sugar crystallization that can damage embedded proteins. In this study, we compare the end moisture content (EMC) as a function of processing time of samples dried with two different light sources, Nd:YAG (1064 nm) and Thulium fiber (1850 nm) lasers. EMC is the ratio of water to dry weight in a sample and the lower the EMC the higher the possible storage temperature. LAD with the 1064 and 1850 nm lasers yielded 78% and 65% lower EMC, respectively, than standard air-drying. After 40 minutes of LAD with 1064 and 1850 nm sources, EMCs of 0.27+/-.27 and 0.15+/-.05 gH2O/gDryWeight were reached, which are near the desired value of 0.10 gH2O/gDryWeight that enables storage in a glassy state without refrigeration. LAD is a promising new technique for the preparation of biologics for anhydrous preservation.

Coronary artery size and origin imaging in children: a comparative study of MRI and trans-thoracic echocardiography.

PubMed

Hussain, Tarique; Mathur, Sujeev; Peel, Sarah A; Valverde, Israel; Bilska, Karolina; Henningsson, Markus; Botnar, Rene M; Simpson, John; Greil, Gerald F

2015-10-27

The purpose of this study was to see how coronary magnetic resonance angiography (CMRA) compared to echocardiography for the detection of coronary artery origins and to compare CMRA measurements for coronary dimensions in children with published echocardiographic reference values. Enrolled patients underwent dual cardiac phase CMRA and echocardiography under the same anesthetic. Echocardiographic measurements of the right coronary artery (RCA), left anterior descending (LAD) and left main (LM) were made. CMRA dimensions were assessed manually at the same points as the echocardiographic measurements. The number of proximal LAD branches imaged was also recorded in order to give an estimate of distal coronary tree visualization. Fifty patients (24 boys, mean age 4.0 years (range 18 days to 18 years)) underwent dual-phase CMRA. Coronary origins were identified in 47/50 cases for CMRA (remaining 3 were infants aged 3, 9 and 11 months). In comparison, origins were identified in 41/50 cases for echo (remaining were all older children). CMRA performed better than echocardiography in terms of distal visualization of the coronary tree (median 1 LAD branch vs. median 0; p = 0.001). Bland-Altman plots show poor agreement between echocardiography and CMRA for coronary measurements. CMRA measurements did vary according to cardiac phase (systolic mean 1.90, s.d. 0.05 mm vs. diastolic mean 1.84, s.d. 0.05 mm; p = 0.002). Dual-phase CMRA has an excellent (94 %) success rate for the detection of coronary origins in children. Newborn infants remain challenging and echocardiography remains the accepted imaging modality for this age group. Echocardiographic reference ranges are not applicable to CMRA measurements as agreement was poor between modalities. Future coronary reference values, using any imaging modality, should quote the phase in which it was measured.

Intravascular Ultrasound Classification of Plaque in Angiographic True Bifurcation Lesions of the Left Main Coronary Artery.

PubMed

Li, Li; Dash, Debabrata; Gai, Lu-Yue; Cao, Yun-Shan; Zhao, Qiang; Wang, Ya-Rong; Zhang, Yao-Jun; Zhang, Jun-Xia

2016-07-05

Accurately, characterizing plaques is critical for selecting the optimal intervention strategy for the left main coronary artery (LMCA) bifurcation. Coronary angiography cannot precisely assess the location or nature of plaques in bifurcation lesions. Few intravascular ultrasound (IVUS) classification scheme has been reported for angiographic imaging of true bifurcation lesions of the unprotected LMCA thus far. In addition, the plaque composition at the bifurcation has not been elucidated. This study aimed to detect plaque composition at LMCA bifurcation lesions by IVUS. Fifty-eight patients were recruited. The location, concentricity or eccentricity, site of maximum thickness, and composition of plaques of the distal LMCA, ostial left anterior descending (LAD) coronary artery and, left circumflex (LCX) coronary artery were assessed using IVUS and described using illustrative diagrams. True bifurcation lesions of the unprotected LMCA were classified into four types: Type A, with continuous involvement from the distal LMCA to the ostial LAD and the ostial LCX with eccentric plaques; Type B, with concentric plaques at the distal LMCA, eccentric plaques at the ostial LAD, and no plaques at the LCX; Type C, with continuous involvement from the distal LMCA to the ostial LCX, with eccentric plaques, and to the ostial LAD, with eccentric plaques; and Type D, with continuous involvement from the distal LMCA to the ostial LAD, with eccentric plaques, and to the ostial LCX, with concentric plaques. The carina was involved in only 3.5% of the plaques. A total of 51.7% of the plaques at the ostium of the LAD were soft, while 44.8% and 44.6% were fibrous in the distal LMCA and in the ostial LCX, respectively. We classified LMCA true bifurcation lesions into four types. The carina was always free from disease. Plaques at the ostial LAD tended to be soft, whereas those at the ostial LCX and the distal LMCA tended to be fibrous.

Patients with left bundle branch block and left axis deviation show a specific left ventricular asynchrony pattern: Implications for left ventricular lead placement during CRT implantation.

PubMed

Sciarra, Luigi; Golia, Paolo; Palamà, Zefferino; Scarà, Antonio; De Ruvo, Ermenegildo; Borrelli, Alessio; Martino, Anna Maria; Minati, Monia; Fagagnini, Alessandro; Tota, Claudia; De Luca, Lucia; Grieco, Domenico; Delise, Pietro; Calò, Leonardo

Left bundle branch block (LBBB) and left axis deviation (LAD) patients may have poor response to resynchronization therapy (CRT). We sought to assess if LBBB and LAD patients show a specific pattern of mechanical asynchrony. CRT candidates with non-ischemic cardiomyopathy and LBBB were categorized as having normal QRS axis (within -30° and +90°) or LAD (within -30° and -90°). Patients underwent tissue Doppler imaging (TDI) to measure time interval between onset of QRS complex and peak systolic velocity in ejection period (Q-peak) at basal segments of septal, inferior, lateral and anterior walls, as expression of local timing of mechanical activation. Thirty patients (mean age 70.6years; 19 males) were included. Mean left ventricular ejection fraction was 0.28±0.06. Mean QRS duration was 172.5±13.9ms. Fifteen patients showed LBBB with LAD (QRS duration 173±14; EF 0.27±0.06). The other 15 patients had LBBB with a normal QRS axis (QRS duration 172±14; EF 0.29±0.05). Among patients with LAD, Q-peak interval was significantly longer at the anterior wall in comparison to each other walls (septal 201±46ms, inferior 242±58ms, lateral 267±45ms, anterior 302±50ms; p<0.0001). Conversely, in patients without LAD Q-peak interval was longer at lateral wall, when compared to each other (septal 228±65ms, inferior 250±64ms, lateral 328±98ms, anterior 291±86ms; p<0.0001). Patients with heart failure, presenting LBBB and LAD, show a specific pattern of ventricular asynchrony, with latest activation at anterior wall. This finding could affect target vessel selection during CRT procedures in these patients. Copyright © 2017 Elsevier Inc. All rights reserved.

Rats bred for high alcohol drinking are more sensitive to delayed and probabilistic outcomes.

PubMed

Wilhelm, C J; Mitchell, S H

2008-10-01

Alcoholics and heavy drinkers score higher on measures of impulsivity than nonalcoholics and light drinkers. This may be because of factors that predate drug exposure (e.g. genetics). This study examined the role of genetics by comparing impulsivity measures in ethanol-naive rats selectively bred based on their high [high alcohol drinking (HAD)] or low [low alcohol drinking (LAD)] consumption of ethanol. Replicates 1 and 2 of the HAD and LAD rats, developed by the University of Indiana Alcohol Research Center, completed two different discounting tasks. Delay discounting examines sensitivity to rewards that are delayed in time and is commonly used to assess 'choice' impulsivity. Probability discounting examines sensitivity to the uncertain delivery of rewards and has been used to assess risk taking and risk assessment. High alcohol drinking rats discounted delayed and probabilistic rewards more steeply than LAD rats. Discount rates associated with probabilistic and delayed rewards were weakly correlated, while bias was strongly correlated with discount rate in both delay and probability discounting. The results suggest that selective breeding for high alcohol consumption selects for animals that are more sensitive to delayed and probabilistic outcomes. Sensitivity to delayed or probabilistic outcomes may be predictive of future drinking in genetically predisposed individuals.

An RF Sensor for Gauging Screen-Channel Liquid Acquisition Devices for Cryogenic Propellants

NASA Technical Reports Server (NTRS)

Zimmerli, Gregory A.; Metzger, Scott; Asipauskas, Marius

2014-01-01

A key requirement of a low-gravity screen-channel liquid acquisition device (LAD) is the need to retain 100% liquid in the channel in response to propellant outflow and spacecraft maneuvers. The point at which a screen-channel LAD ingests vapor is known as breakdown, and can be measured several different ways such as: visual observation of bubbles in the LAD channel outflow; a sudden change in pressure drop between the propellant tank and LAD sump outlet; or, an indication by wet-dry sensors placed in the LAD channel or outflow stream. Here we describe a new type of sensor for gauging a screen-channel LAD, the Radio Frequency Mass Gauge (RFMG). The RFMG measures the natural electromagnetic modes of the screen-channel LAD, which is very similar to an RF waveguide, to determine the amount of propellant in the channel. By monitoring several of the RF modes, we show that the RFMG acts as a global sensor of the LAD channel propellant fill level, and enables detection of LAD breakdown even in the absence of outflow. This paper presents the theory behind the RFMG-LAD sensor, measurements and simulations of the RF modes of a LAD channel, and RFMG detection of LAD breakdown in a channel using a simulant fluid during inverted outflow and long-term stability tests.

Effect of the degree of LAD stenosis on "competitive flow" and flow field characteristics in LIMA-to-LAD bypass surgery.

PubMed

Swillens, Abigail; De Witte, Marloes; Nordgaard, Håvard; Løvstakken, Lasse; Van Loo, Denis; Trachet, Bram; Vierendeels, Jan; Segers, Patrick

2012-08-01

The long-term patency of the left internal mammary artery (LIMA) in left anterior descending (LAD) coronary stenosis bypass surgery is believed to be related to the degree of competitive flow between the LAD and LIMA. To investigate the effect of the LAD stenosis severity on this phenomenon and on haemodynamics in the LIMA and anastomosis region, a numerical LIMA-LAD model was developed based on 3D geometric (obtained from a cast) and hemodynamic data from an experimental pig study. Proximal LAD pressure was used as upstream boundary condition. The model counted 13 outlets (12 septal arteries and the distal LAD) where flow velocities were imposed in systole, while myocardial conductance was imposed in diastole via an implicit scheme. LAD stenoses of 100 (total occlusion), 90, 75 and 0 % area reduction were constructed. Low degree of LAD stenosis was associated with highly competitive flow and low wall shear stress (WSS) in the LIMA, an unfavourable hemodynamic regime which might contribute to WSS-related remodelling of the LIMA and suboptimal long-term LIMA bypass performance.

Simulations of Seasonal and Latitudinal Variations in Leaf Inclination Angle Distribution: Implications for Remote Sensing

NASA Technical Reports Server (NTRS)

Huemmrich, Karl F.

2013-01-01

The leaf inclination angle distribution (LAD) is an important characteristic of vegetation canopy structure affecting light interception within the canopy. However, LADs are difficult and time consuming to measure. To examine possible global patterns of LAD and their implications in remote sensing, a model was developed to predict leaf angles within canopies. Canopies were simulated using the SAIL radiative transfer model combined with a simple photosynthesis model. This model calculated leaf inclination angles for horizontal layers of leaves within the canopy by choosing the leaf inclination angle that maximized production over a day in each layer. LADs were calculated for five latitude bands for spring and summer solar declinations. Three distinct LAD types emerged: tropical, boreal, and an intermediate temperate distribution. In tropical LAD, the upper layers have a leaf angle around 35 with the lower layers having horizontal inclination angles. While the boreal LAD has vertical leaf inclination angles throughout the canopy. The latitude bands where each LAD type occurred changed with the seasons. The different LADs affected the fraction of absorbed photosynthetically active radiation (fAPAR) and Normalized Difference Vegetation Index (NDVI) with similar relationships between fAPAR and leaf area index (LAI), but different relationships between NDVI and LAI for the different LAD types. These differences resulted in significantly different relationships between NDVI and fAPAR for each LAD type. Since leaf inclination angles affect light interception, variations in LAD also affect the estimation of leaf area based on transmittance of light or lidar returns.

Computational hemodynamics of an implanted coronary stent based on three-dimensional cine angiography reconstruction.

PubMed

Chen, Mounter C Y; Lu, Po-Chien; Chen, James S Y; Hwang, Ned H C

2005-01-01

Coronary stents are supportive wire meshes that keep narrow coronary arteries patent, reducing the risk of restenosis. Despite the common use of coronary stents, approximately 20-35% of them fail due to restenosis. Flow phenomena adjacent to the stent may contribute to restenosis. Three-dimensional computational fluid dynamics (CFD) and reconstruction based on biplane cine angiography were used to assess coronary geometry and volumetric blood flows. A patient-specific left anterior descending (LAD) artery was reconstructed from single-plane x-ray imaging. With corresponding electrocardiographic signals, images from the same time phase were selected from the angiograms for dynamic three-dimensional reconstruction. The resultant three-dimensional LAD artery at end-diastole was adopted for detailed analysis. Both the geometries and flow fields, based on a computational model from CAE software (ANSYS and CATIA) and full three-dimensional Navier-Stroke equations in the CFD-ACE+ software, respectively, changed dramatically after stent placement. Flow fields showed a complex three-dimensional spiral motion due to arterial tortuosity. The corresponding wall shear stresses, pressure gradient, and flow field all varied significantly after stent placement. Combined angiography and CFD techniques allow more detailed investigation of flow patterns in various segments. The implanted stent(s) may be quantitatively studied from the proposed hemodynamic modeling approach.

Arachidonic and linoleic acid derivatives impact oocyte ICSI fertilization--a prospective analysis of follicular fluid and a matched oocyte in a 'one follicle--one retrieved oocyte--one resulting embryo' investigational setting.

PubMed

Ciepiela, Przemysław; Bączkowski, Tomasz; Drozd, Arleta; Kazienko, Anna; Stachowska, Ewa; Kurzawa, Rafał

2015-01-01

To evaluate human oocyte ability to undergo fertilization and subsequent preimplantation embryonic development in relation to a wide panel of follicular fluid (FF) arachidonic acid derivatives (AAD) and linoleic acid derivatives (LAD) of prospectively selected patients undergoing intracytoplasmic sperm injection (ICSI). Study was designed as a two center (a university clinic and a private clinic) prospective study. 54 women of 181 consecutive couples undergoing ICSI were prospectively found to be eligible for analysis. 'One follicle - one retrieved oocyte - one resulting embryo' approach was used. Each individual follicle was aspirated independently and matched to an oocyte growing in this particular follicular milieu. FF samples were assessed for AAD and LAD by high-performance liquid chromatography; additionally, activity of secretory phospholipase A (sPLA2) was determined by enzyme-linked immunosorbent assay. Increased activity of sPLA2 and significantly higher AAD and LAD levels were found in FF of oocytes that did not show two pronuclei or underwent degeneration after ICSI in comparison to oocytes with the appearance of two pronuclei. Receiver operating characteristics curve analysis identified acids with the highest sensitivity and specificity: 5oxo-hydroxyeicosatetraenoic, 16-hydroxyeicosatetraenoic, 9-hydroxyoctadecadieneoic and 12-hydroxyeicosatetraenoic. No significant differences between AAD and LAD related to embryo quality were found. Our study demonstrates for the first time that elevated concentrations of AAD and LAD in FF at the time of oocyte retrieval significantly decrease the ability of oocytes to form pronuclei after ICSI. This may serve as a new tool for non-invasive assessment of oocyte developmental capacity. However, levels of AAD and LAD are not associated with subsequent embryo quality or pregnancy rate, and therefore more studies are needed to determine their usefulness in human IVF procedure.

Arachidonic and Linoleic Acid Derivatives Impact Oocyte ICSI Fertilization – A Prospective Analysis of Follicular Fluid and a Matched Oocyte in a ‘One Follicle – One Retrieved Oocyte – One Resulting Embryo’ Investigational Setting

PubMed Central

Bączkowski, Tomasz; Drozd, Arleta; Kazienko, Anna

2015-01-01

Objective To evaluate human oocyte ability to undergo fertilization and subsequent preimplantation embryonic development in relation to a wide panel of follicular fluid (FF) arachidonic acid derivatives (AAD) and linoleic acid derivatives (LAD) of prospectively selected patients undergoing intracytoplasmic sperm injection (ICSI). Methodology Study was designed as a two center (a university clinic and a private clinic) prospective study. 54 women of 181 consecutive couples undergoing ICSI were prospectively found to be eligible for analysis. 'One follicle – one retrieved oocyte – one resulting embryo' approach was used. Each individual follicle was aspirated independently and matched to an oocyte growing in this particular follicular milieu. FF samples were assessed for AAD and LAD by high-performance liquid chromatography; additionally, activity of secretory phospholipase A (sPLA2) was determined by enzyme-linked immunosorbent assay. Principal Findings Increased activity of sPLA2 and significantly higher AAD and LAD levels were found in FF of oocytes that did not show two pronuclei or underwent degeneration after ICSI in comparison to oocytes with the appearance of two pronuclei. Receiver operating characteristics curve analysis identified acids with the highest sensitivity and specificity: 5oxo-hydroxyeicosatetraenoic, 16-hydroxyeicosatetraenoic, 9-hydroxyoctadecadieneoic and 12-hydroxyeicosatetraenoic. No significant differences between AAD and LAD related to embryo quality were found. Conclusions/Significance Our study demonstrates for the first time that elevated concentrations of AAD and LAD in FF at the time of oocyte retrieval significantly decrease the ability of oocytes to form pronuclei after ICSI. This may serve as a new tool for non-invasive assessment of oocyte developmental capacity. However, levels of AAD and LAD are not associated with subsequent embryo quality or pregnancy rate, and therefore more studies are needed to determine their usefulness in human IVF procedure. PMID:25763593

Bubble Point Measurements with Liquid Methane of a Screen Channel Capillary Liquid Acquisition Device

NASA Technical Reports Server (NTRS)

Jurns, John M.; McQuillen, John B.; Gaby, Joseph D., Jr.; Sinacore, Steven A., Jr.

2009-01-01

Liquid acquisition devices (LADs) can be utilized within a propellant tank in space to deliver single-phase liquid to the engine in low gravity. One type of liquid acquisition device is a screened gallery whereby a fine mesh screen acts as a 'bubble filter' and prevents the gas bubbles from passing through until a crucial pressure differential condition across the screen, called the bubble point, is reached. This paper presents data for LAD bubble point data in liquid methane (LCH4) for stainless steel Dutch twill screens with mesh sizes of 325 by 2300. These tests represent the first known nonproprietary effort to collect bubble point data for LCH4.

Influence of different treatment techniques on radiation dose to the LAD coronary artery

PubMed Central

Nieder, Carsten; Schill, Sabine; Kneschaurek, Peter; Molls, Michael

2007-01-01

Background The purpose of this proof-of-principle study was to test the ability of an intensity-modulated radiotherapy (IMRT) technique to reduce the radiation dose to the heart plus the left ventricle and a coronary artery. Radiation-induced heart disease might be a serious complication in long-term cancer survivors. Methods Planning CT scans from 6 female patients were available. They were part of a previous study of mediastinal IMRT for target volumes used in lymphoma treatment that included 8 patients and represent all cases where the left anterior descending coronary artery (LAD) could be contoured. We compared 6 MV AP/PA opposed fields to a 3D conformal 4-field technique and an optimised 7-field step-and-shoot IMRT technique and evaluated DVH's for several structures. The planning system was BrainSCAN 5.21 (BrainLAB, Heimstetten, Germany). Results IMRT maintained target volume coverage but resulted in better dose reduction to the heart, left ventricle and LAD than the other techniques. Selective dose reduction could be accomplished, although not to the degree initially attempted. The median LAD dose was approximately 50% lower with IMRT. In 5 out of 6 patients, IMRT was the best technique with regard to heart sparing. Conclusion IMRT techniques are able to reduce the radiation dose to the heart. In addition to dose reduction to whole heart, individualised dose distributions can be created, which spare, e.g., one ventricle plus one of the coronary arteries. Certain patients with well-defined vessel pathology might profit from an approach of general heart sparing with further selective dose reduction, accounting for the individual aspects of pre-existing damage. PMID:17547777

A Simple Numerical Body Surface Mapping Parameter Signifies Successful Percutaneous Coronary Artery Intervention.

PubMed

Simonyi, Gábor; Kirschner, Róbert; Szűcs, Endre; Préda, István; Duray, Gábor; Medvegy, Nóra; Horvath, Bálint; Medvegy, Mihály

2016-03-01

In coronary artery disease (CAD), body surface potential mapping (BSPM) may reveal minor electrical potential changes appearing in the depolarization phase even if pathological changes are absent on the conventional 12-lead ECG. We hypothesized that a simple BSPM parameter, Max/Min signifies successful percutaneous coronary intervention (PCI). Ninety-two adult Caucasian patients with stable CAD and positive exercise test underwent coronary angiography. Seventy patients (age, 59 ± 8; 46 males) were revascularized by PCI (left anterior descending [LAD] in 38, right [RCA] in 17 and left circumflex [LCX] coronary artery in 15). Control groups contained 22 patients (age, 60 ± 8; 14 males) without intervention and 35 healthy subjects (age, 58 ± 2; 15 males). Left ventricular ejection fraction (LVEF, transthoracic echocardiography) and Max/Min BSPM parameter (63-lead Montreal system) were evaluated before and 4-40 days following coronary angiography. Max/Min was defined by the ratio of the highest maximum to the deepest minimum potential of all leads recorded by BSPM. Before PCI, Max/Min value of patients with LAD lesion (0.83 [0.74; 0.93]) was significantly lower while that with RCA lesion (1.63 [1.35; 1.99]) was significantly higher than that of healthy group (1.01 [0.970; 1.13]) (P < 0.05) and LVEF was significantly lower in LAD lesion (46.50% [43.00; 51.00]) than in the healthy group (55.00% [50.00; 58.75]) (P < 0.01). Max/Min value significantly increased from 0.83 [0.74; 0.93] to 0.92 [0.82; 0.99] (P < 0.01) following LAD PCI while significantly decreased from 1.63 [1.35; 1.98] to 1.35 [1.21; 1.43] (P < 0.01) post-RCA PCI. It did not vary significantly, however, either following LCX PCI or without intervention. LVEF significantly increased (from 46.50% [43.00; 51.00] to 49.00% [46.00; 51.00]) only after LAD PCI. Max/Min parameter is suitable to follow patients after LAD and RCA PCI. © 2015 Wiley Periodicals, Inc.

[Minimally invasive coronary artery surgery].

PubMed

Zalaquett, R; Howard, M; Irarrázaval, M J; Morán, S; Maturana, G; Becker, P; Medel, J; Sacco, C; Lema, G; Canessa, R; Cruz, F

1999-01-01

There is a growing interest to perform a left internal mammary artery (LIMA) graft to the left anterior descending coronary artery (LAD) on a beating heart through a minimally invasive access to the chest cavity. To report the experience with minimally invasive coronary artery surgery. Analysis of 11 patients aged 48 to 79 years old with single vessel disease that, between 1996 and 1997, had a LIMA graft to the LAD performed through a minimally invasive left anterior mediastinotomy, without cardiopulmonary bypass. A 6 to 10 cm left parasternal incision was done. The LIMA to the LAD anastomosis was done after pharmacological heart rate and blood pressure control and a period of ischemic pre conditioning. Graft patency was confirmed intraoperatively by standard Doppler techniques. Patients were followed for a mean of 11.6 months (7-15 months). All patients were extubated in the operating room and transferred out of the intensive care unit on the next morning. Seven patients were discharged on the third postoperative day. Duplex scanning confirmed graft patency in all patients before discharge; in two patients, it was confirmed additionally by arteriography. There was no hospital mortality, no perioperative myocardial infarction and no bleeding problems. After follow up, ten patients were free of angina, in functional class I and pleased with the surgical and cosmetic results. One patient developed atypical angina on the seventh postoperative month and a selective arteriography confirmed stenosis of the anastomosis. A successful angioplasty of the original LAD lesion was carried out. A minimally invasive left anterior mediastinotomy is a good surgical access to perform a successful LIMA to LAD graft without cardiopulmonary bypass, allowing a shorter hospital stay and earlier postoperative recovery. However, a larger experience and a longer follow up is required to define its role in the treatment of coronary artery disease.

Return of the lysergamides. Part III: Analytical characterization of N6 -ethyl-6-norlysergic acid diethylamide (ETH-LAD) and 1-propionyl ETH-LAD (1P-ETH-LAD).

PubMed

Brandt, Simon D; Kavanagh, Pierce V; Westphal, Folker; Elliott, Simon P; Wallach, Jason; Stratford, Alexander; Nichols, David E; Halberstadt, Adam L

2017-10-01

The psychoactive properties of lysergic acid diethylamide (LSD) have fascinated scientists across disciplines and the exploration of other analogues and derivatives has been motivated by deepening the understanding of ligand-receptor interactions at the molecular level as well as by the search for new therapeutics. Several LSD congeners have appeared on the new psychoactive substances (NPS) market in the form of blotters or powders. Examples include 1-propionyl-LSD (1P-LSD), AL-LAD, and LSZ. The absence of analytical data for novel compounds is a frequent challenge encountered in clinical and toxicological investigations. Two newly emerging lysergamides, namely N 6 -ethyl-6-norlysergic acid diethylamide (ETH-LAD) and 1P-ETH-LAD, were characterized by gas chromatography-mass spectrometry (GC-MS), low and high mass accuracy electrospray MS(/MS), GC solid-state infrared analysis, high performance liquid chromatography diode array detection as well as nuclear magnetic resonance spectroscopy. Limited analytical data for ETH-LAD were previously available, whereas information about 1P-ETH-LAD has not previously been encountered in the scientific literature. This study extends the characterization of lysergamides distributed on the NPS market, which will help to make analytical data available to clinicians, toxicologists, and other stakeholders who are likely to encounter these substances. The analysis of a test incubation of 1P-ETH-LAD with human serum at 37°C by LC single quadrupole MS at various time points (0-6 h, once per hour and one measurement after 24 h) revealed the formation of ETH-LAD, suggesting that 1P-ETH-LAD might serve as a pro-drug. 1P-ETH-LAD was still detectable in serum after 24 h. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Structural classification of marshes with Polarimetric SAR highlighting the temporal mapping of marshes exposed to oil

USGS Publications Warehouse

Ramsey, Elijah W.; Rangoonwala, Amina; Jones, Cathleen E.

2015-01-01

Empirical relationships between field-derived Leaf Area Index (LAI) and Leaf Angle Distribution (LAD) and polarimetric synthetic aperture radar (PolSAR) based biophysical indicators were created and applied to map S. alterniflora marsh canopy structure. PolSAR and field data were collected near concurrently in the summers of 2010, 2011, and 2012 in coastal marshes, and PolSAR data alone were acquired in 2009. Regression analyses showed that LAI correspondence with the PolSAR biophysical indicator variables equaled or exceeded those of vegetation water content (VWC) correspondences. In the final six regressor model, the ratio HV/VV explained 49% of the total 77% explained LAI variance, and the HH-VV coherence and phase information accounted for the remainder. HV/HH dominated the two regressor LAD relationship, and spatial heterogeneity and backscatter mechanism followed by coherence information dominated the final three regressor model that explained 74% of the LAD variance. Regression results applied to 2009 through 2012 PolSAR images showed substantial changes in marsh LAI and LAD. Although the direct cause was not substantiated, following a release of freshwater in response to the 2010 Deepwater Horizon oil spill, the fairly uniform interior marsh structure of 2009 was more vertical and dense shortly after the oil spill cessation. After 2010, marsh structure generally progressed back toward the 2009 uniformity; however, the trend was more disjointed in oil impact marshes.             

Bubble Point Measurements with Liquid Methane of a Screen Capillary Liquid Acquisition Device

NASA Technical Reports Server (NTRS)

Jurns, John M.; McQuillen, John B.

2009-01-01

Liquid acquisition devices (LADs) can be utilized within a propellant tank in space to deliver single-phase liquid to the engine in low gravity. One type of liquid acquisition device is a screened gallery whereby a fine mesh screen acts as a bubble filter and prevents the gas bubbles from passing through until a crucial pressure differential condition across the screen, called the bubble point, is reached. This paper presents data for LAD bubble point data in liquid methane (LCH4) for stainless steel Dutch twill screens with mesh sizes of 325 by 2300 and 200 by 1400 wires per inch. Data is presented for both saturated and sub-cooled LCH4, and is compared with predicted values.

"Lights on at the end of the party": are lads' mags mainstreaming dangerous sexism?

PubMed

Horvath, Miranda A H; Hegarty, Peter; Tyler, Suzannah; Mansfield, Sophie

2012-11-01

Research has suggested that some magazines targeted at young men - lads' mags - are normalizing extreme sexist views by presenting those views in a mainstream context. Consistent with this view, young men in Study 1 (n = 90) identified more with derogatory quotes about women drawn from recent lads' mags, and from interviews with convicted rapists, when those quotes were attributed to lads' mags, than when they were attributed to convicted rapists. In Study 2, 40 young women and men could not reliably judge the source of those same quotes. While these participants sometimes voiced the belief that the content of lads' mags was 'normal' while rapists' talk was 'extreme', they categorized quotes from both sources as derogatory with equal frequency. Jointly, the two studies show an overlap in the content of convicted rapists' talk and the contents of contemporary lads' mags, and suggest that the framing of such content within lads' mags may normalize it for young men. ©2011 The British Psychological Society.

Laser-driven atomic-probe-beam diagnostics

NASA Astrophysics Data System (ADS)

Knyazev, B. A.; Greenly, J. B.; Hammer, D. A.

2000-12-01

A new laser-driven atomic-probe-beam diagnostic (LAD) is proposed for local, time-resolved measurements of electric field and ion dynamics in the accelerating gap of intense ion beam diodes. LAD adds new features to previous Stark-shift diagnostics which have been progressively developed in several laboratories, from passive observation of Stark effect on ion species or fast (charge-exchanged) neutrals present naturally in diodes, to active Stark atomic spectroscopy (ASAS) in which selected probe atoms were injected into the gap and excited to suitable states by resonant laser radiation. The LAD scheme is a further enhancement of ASAS in which the probe atoms are also used as a local (laser-ionized) ion source at an instant of time. Analysis of the ion energy and angular distribution after leaving the gap enables measurement, at the chosen ionization location in the gap, of both electrostatic potential and the development of ion divergence. Calculations show that all of these quantities can be measured with sub-mm and ns resolution. Using lithium or sodium probe atoms, fields from 0.1 to 10 MV/cm can be measured.

A single amino acid change (Y318F) in the L-arabitol dehydrogenase (LadA) from Aspergillus niger results in a significant increase in affinity for D-sorbitol

PubMed Central

2009-01-01

Background L-arabitol dehydrogenase (LAD) and xylitol dehydrogenase (XDH) are involved in the degradation of L-arabinose and D-xylose, which are among the most abundant monosaccharides on earth. Previous data demonstrated that LAD and XDH not only differ in the activity on their biological substrate, but also that only XDH has significant activity on D-sorbitol and may therefore be more closely related to D-sorbitol dehydrogenases (SDH). In this study we aimed to identify residues involved in the difference in substrate specificity. Results Phylogenetic analysis demonstrated that LAD, XDH and SDH form 3 distinct groups of the family of dehydrogenases containing an Alcohol dehydrogenase GroES-like domain (pfam08240) and likely have evolved from a common ancestor. Modelling of LadA and XdhA of the saprobic fungus Aspergillus niger on human SDH identified two residues in LadA (M70 and Y318), that may explain the absence of activity on D-sorbitol. While introduction of the mutation M70F in LadA of A. niger resulted in a nearly complete enzyme inactivation, the Y318F resulted in increased activity for L-arabitol and xylitol. Moreover, the affinity for D-sorbitol was increased in this mutant. Conclusion These data demonstrates that Y318 of LadA contributes significantly to the substrate specificity difference between LAD and XDH/SDH. PMID:19674460

Comparison of adenosine, isoflurane, and desflurane on myocardial tissue oxygen pressure during coronary artery constriction in dogs.

PubMed

Hoffman, William E; Albrecht, Ronald F; Jonjev, Zivojin S

2003-08-01

To compare adenosine-, isoflurane-, or desflurane-induced hypotension with and without left anterior descending (LAD) coronary artery constriction for the effects on myocardial tissue oxygen pressure (PmO(2)) in dogs. Prospective, randomized, nonblinded. University teaching hospital. Male nonpurpose-bred dogs (n = 18). Dogs were anesthetized with 1.5% isoflurane (n = 12) or 8% desflurane (n = 6). A flow probe and balloon occluder were placed on the LAD artery. A probe that measured myocardial oxygen pressure was inserted into the middle myocardium in the LAD region. Myocardial oxygen consumption (MVO(2)) was calculated as LAD flow x arterial minus coronary sinus oxygen content. Measures were made during hypotension produced by adenosine infusion, 2.8% isoflurane, or 14% desflurane with and without LAD constriction to decrease blood flow 30%. Without LAD artery constriction, adenosine infusion increased LAD flow 90% and MVO(2) 70%, 2.8% isoflurane produced no change in MVO(2), and 14% desflurane decreased MVO(2) 25%, but no treatment changed PmO(2). LAD artery constriction decreased PmO(2) 50% by itself. Adenosine infusion during LAD constriction decreased tissue oxygen pressure an additional 60%, 2.8% isoflurane produced no change, and 14% desflurane increased PmO(2) 100%. There was an inverse relationship between the effect of adenosine, 2.8% isoflurane, and 14% desflurane on MVO(2) and PmO(2) during ischemia. This is consistent with reports that increasing oxygen demand worsens myocardial ischemia.

Louisiana SIP: LAC 33:III Ch 2132. Stage II Vapor Recovery Systems for Control of Vehicle Refuelling Emissions at Gasoline Dispensing Facilities; SIP effective 2011-08-04 (LAd34) and 2016-02-29 (LAd47) to 2017-09-27

EPA Pesticide Factsheets

Louisiana SIP: LAC 33:III Ch 2132. Stage II Vapor Recovery Systems for Control of Vehicle Refuelling Emissions at Gasoline Dispensing Facilities; SIP effective 2011-08-04 (LAd34) and 2016-02-29 (LAd47) to 2017-09-27

Assessment of Intrafraction Breathing Motion on Left Anterior Descending Artery Dose During Left-Sided Breast Radiation Therapy

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

El-Sherif, Omar, E-mail: Omar.ElSherif@lhsc.on.ca; Department of Physics, London Regional Cancer Program, London, Ontario; Yu, Edward

Purpose: To use 4-dimensional computed tomography (4D-CT) imaging to predict the level of uncertainty in cardiac dose estimates of the left anterior descending artery that arises due to breathing motion during radiation therapy for left-sided breast cancer. Methods and Materials: The fast helical CT (FH-CT) and 4D-CT of 30 left-sided breast cancer patients were retrospectively analyzed. Treatment plans were created on the FH-CT. The original treatment plan was then superimposed onto all 10 phases of the 4D-CT to quantify the dosimetric impact of respiratory motion through 4D dose accumulation (4D-dose). Dose-volume histograms for the heart, left ventricle (LV), and left anteriormore » descending (LAD) artery obtained from the FH-CT were compared with those obtained from the 4D-dose. Results: The 95% confidence interval of 4D-dose and FH-CT differences in mean dose estimates for the heart, LV, and LAD were ±0.5 Gy, ±1.0 Gy, and ±8.7 Gy, respectively. Conclusion: Fast helical CT is a good approximation for doses to the heart and LV; however, dose estimates for the LAD are susceptible to uncertainties that arise due to intrafraction breathing motion that cannot be ascertained without the additional information obtained from 4D-CT and dose accumulation. For future clinical studies, we suggest the use of 4D-CT–derived dose-volume histograms for estimating the dose to the LAD.« less

Single-cell dynamics of genome-nuclear lamina interactions.

PubMed

Kind, Jop; Pagie, Ludo; Ortabozkoyun, Havva; Boyle, Shelagh; de Vries, Sandra S; Janssen, Hans; Amendola, Mario; Nolen, Leisha D; Bickmore, Wendy A; van Steensel, Bas

2013-03-28

The nuclear lamina (NL) interacts with hundreds of large genomic regions termed lamina associated domains (LADs). The dynamics of these interactions and the relation to epigenetic modifications are poorly understood. We visualized the fate of LADs in single cells using a "molecular contact memory" approach. In each nucleus, only ~30% of LADs are positioned at the periphery; these LADs are in intermittent molecular contact with the NL but remain constrained to the periphery. Upon mitosis, LAD positioning is not detectably inherited but instead is stochastically reshuffled. Contact of individual LADs with the NL is linked to transcriptional repression and H3K9 dimethylation in single cells. Furthermore, we identify the H3K9 methyltransferase G9a as a regulator of NL contacts. Collectively, these results highlight principles of the dynamic spatial architecture of chromosomes in relation to gene regulation. Copyright © 2013 Elsevier Inc. All rights reserved.

Patterns and associations between DAPT cessation and 2-year clinical outcomes in left main/proximal LAD versus other PCI: Results from the Patterns of Non-Adherence to Dual Antiplatelet Therapy in Stented Patients (PARIS) registry.

PubMed

Chandrasekhar, Jaya; Baber, Usman; Sartori, Samantha; Aquino, Melissa; Tomey, Matthew; Kruckoff, Mitchell; Moliterno, David; Henry, Timothy D; Weisz, Giora; Gibson, C Michael; Iakovou, Ioannis; Kini, Annapoorna; Faggioni, Michela; Vogel, Birgit; Farhan, Serdar; Colombo, Antonio; Steg, P Gabriel; Witzenbichler, Bernhard; Chieffo, Alaide; Cohen, David; Stuckey, Thomas; Ariti, Cono; Pocock, Stuart; Dangas, George; Mehran, Roxana

2017-09-15

Percutaneous coronary intervention (PCI) of the left main (LM) or proximal left anterior descending artery (pLAD) is considered high-risk as these segments subtend substantial left ventricular myocardial area. We assessed the patterns and associations between dual antiplatelet therapy (DAPT) cessation and 2-year outcomes in LM/pLAD vs. other PCI from the all-comer PARIS registry. Two-year major adverse cardiovascular events (MACE) were a composite of cardiac death, myocardial infarction, definite/probable stent thrombosis or target lesion revascularization. DAPT cessation was predefined as physician-guided permanent discontinuation, temporary interruption, or non-recommended disruption due to non-compliance or bleeding. Of the study population (n=5018), 25.0% (n=1252) underwent LM/pLAD PCI and 75.0% (n=3766) PCI to other segments. Compared to others, LM/pLAD patients presented with fewer comorbidities, less frequent acute coronary syndromes but more multivessel and bifurcation disease treated with greater stent lengths. Two-year adjusted risk of MACE (11.4% vs. 11.6%; HR 1.10, 95% CI 0.90-1.34, p=0.36) was similar between LM/pLAD vs. other patients. DAPT discontinuation was significantly higher (43.3% vs. 39.4%, p=0.01) in LM/pLAD patients with borderline significance for lower disruption (10.0% vs. 14.7%, p=0.059) compared to other patients. DAPT discontinuation was not associated with higher risk of MACE in LM/pLAD (HR 0.65, 95% CI 0.34-1.25) or other PCI groups (HR 0.67, 95% CI 0.47-0.95). LM/pLAD PCI was not an independent predictor of 2-year MACE. Compared to other PCI, patients undergoing LM/pLAD PCI had higher rates of physician recommended DAPT discontinuation, however, discontinuation did not result in greater adverse events. Copyright © 2017 Elsevier B.V. All rights reserved.

CO2 sequestration in two mediterranean dune areas subjected to a different level of anthropogenic disturbance

NASA Astrophysics Data System (ADS)

Bonito, Andrea; Ricotta, Carlo; Iberite, Mauro; Gratani, Loretta; Varone, Laura

2017-09-01

Coastal sand dunes are among the most threatened habitats, especially in the Mediterranean Basin, where the high levels of human pressure impair the presence of plant species, putting at risk the maintenance of the ecosystem services, such as CO2 sequestration provided by these habitats. The aim of this study was to analyze how disturbance-induced changes in plant species abundance patterns account for variations in annual CO2 sequestration flow (CS) of Mediterranean sand dune areas. Two sites characterized by a high (site HAD) and a lower (site LAD) anthropogenic disturbance level were selected. At both sites, plant species number, cover, height and CS based on net photosynthesis measurements were sampled. At the plant species level, our results highlighted that Ammophila arenaria and Pancratium maritimum, had a key role in CS. Moreover, the results revealed a patchy species assemblage in both sites. In particular, HAD was characterized by a higher extension of the anthropogenic aphytoic zone (64% of the total transect length) than LAD. In spite of the observed differences in plant species composition, there were not significant differences between HAD and LAD in structural and functional traits, such as plant height and net photosynthesis. As a consequence, HAD and LAD had a similar CS (443 and 421 Mg CO2 ha-1 y-1, respectively). From a monetary point of view, our estimates based on the social costs of carbon revealed that the flow of sequestered CO2 valued on an average 3181 ± 114 ha-1 year-1 (mean value for the two sites). However, considering also the value of the CO2 negative flow related to loss of vegetated area, the annual net benefit arising from CO2 sequestration amounted to 1641 and 1772 for HAD and LAD, respectively. Overall, the results highlighted the importance to maximize the efforts to preserve dune habitats by applying an effective management policy, which could allow maintaining also a regulatory ecosystem service such as CO2 sequestration.

Genome-nuclear lamina interactions: from cell populations to single cells.

PubMed

Yáñez-Cuna, J Omar; van Steensel, Bas

2017-04-01

Lamina-associated domains (LADs) are large genomic regions that interact with the nuclear lamina (NL) and help to guide the spatial folding of chromosomes in the interphase nucleus. LADs have been linked to gene repression and other functions. Recent studies have begun to uncover some of the molecular players that drive LAD-NL interactions. A picture emerges in which DNA sequence, chromatin components and nuclear lamina proteins play an important role. Complementary to this, imaging and single-cell genomics approaches have revealed that some LAD-NL interactions are variable from cell to cell, while others are very stable. Understanding LADs can provide a unique perspective into the general process of genome organization. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Liquid Acquisition Device Hydrogen Outflow Testing on the Cryogenic Propellant Storage and Transfer Engineering Design Unit

NASA Technical Reports Server (NTRS)

Zimmerli, Greg; Statham, Geoff; Garces, Rachel; Cartagena, Will

2015-01-01

As part of the NASA Cryogenic Propellant Storage and Transfer (CPST) Engineering Design Unit (EDU) testing with liquid hydrogen, screen-channel liquid acquisition devices (LADs) were tested during liquid hydrogen outflow from the EDU tank. A stainless steel screen mesh (325x2300 Dutch T will weave) was welded to a rectangular cross-section channel to form the basic LAD channel. Three LAD channels were tested, each having unique variations in the basic design. The LADs fed a common outflow sump at the aft end of the 151 cu. ft. volume aluminum tank, and included a curved section along the aft end and a straight section along the barrel section of the tank. Wet-dry sensors were mounted inside the LAD channels to detect when vapor was ingested into the LADs during outflow. The use of warm helium pressurant during liquid hydrogen outflow, supplied through a diffuser at the top of the tank, always led to early breakdown of the liquid column. When the tank was pressurized through an aft diffuser, resulting in cold helium in the ullage, LAD column hold-times as long as 60 minutes were achieved, which was the longest duration tested. The highest liquid column height at breakdown was 58 cm, which is 23 less than the isothermal bubble-point model value of 75 cm. This paper discusses details of the design, construction, operation and analysis of LAD test data from the CPST EDU liquid hydrogen test.

Massive reshaping of genome-nuclear lamina interactions during oncogene-induced senescence.

PubMed

Lenain, Christelle; de Graaf, Carolyn A; Pagie, Ludo; Visser, Nils L; de Haas, Marcel; de Vries, Sandra S; Peric-Hupkes, Daniel; van Steensel, Bas; Peeper, Daniel S

2017-10-01

Cellular senescence is a mechanism that virtually irreversibly suppresses the proliferative capacity of cells in response to various stress signals. This includes the expression of activated oncogenes, which causes Oncogene-Induced Senescence (OIS). A body of evidence points to the involvement in OIS of chromatin reorganization, including the formation of senescence-associated heterochromatic foci (SAHF). The nuclear lamina (NL) is an important contributor to genome organization and has been implicated in cellular senescence and organismal aging. It interacts with multiple regions of the genome called lamina-associated domains (LADs). Some LADs are cell-type specific, whereas others are conserved between cell types and are referred to as constitutive LADs (cLADs). Here, we used DamID to investigate the changes in genome-NL interactions in a model of OIS triggered by the expression of the common BRAF V600E oncogene. We found that OIS cells lose most of their cLADS, suggesting the loss of a specific mechanism that targets cLADs to the NL. In addition, multiple genes relocated to the NL. Unexpectedly, they were not repressed, implying the abrogation of the repressive activity of the NL during OIS. Finally, OIS cells displayed an increased association of telomeres with the NL. Our study reveals that senescent cells acquire a new type of LAD organization and suggests the existence of as yet unknown mechanisms that tether cLADs to the NL and repress gene expression at the NL. © 2017 Lenain et al.; Published by Cold Spring Harbor Laboratory Press.

Combining PCI and CABG: the role of hybrid revascularization.

PubMed

Green, Kelly D; Lynch, Donald R; Chen, Tyffany P; Zhao, David

2013-04-01

Hybrid coronary revascularization combines the benefits of both percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in the treatment of multivessel coronary artery disease (CAD) by combining the benefits of the LIMA-to-LAD graft and drug eluting stent (DES) to non-LAD regions. Through this approach, a patient receives the long-term benefit of the LIMA graft and avoids the morbidity of a full sternotomy and saphenous vein grafts. Available data related to outcomes following hybrid revascularization is limited to small studies. In this review we seek to provide an overview of hybrid revascularization in the era of modern drug eluting stent technology, discuss appropriate patient selection, and comment on future trial design. Additionally, we review the recent literature pertaining to the hybrid approach.

Prognostic impact of location and extent of vessel-related ischemia at myocardial perfusion scintigraphy in patients with or at risk for coronary artery disease.

PubMed

Nudi, Francesco; Schillaci, Orazio; Neri, Giandomenico; Pinto, Annamaria; Procaccini, Enrica; Vetere, Maurizio; Frati, Giacomo; Tomai, Fabrizio; Biondi-Zoccai, Giuseppe

2016-04-01

Myocardial perfusion scintigraphy (MPS) has an established diagnostic and prognostic role in patients with or at risk for coronary artery disease, with ischemia severity and extent having already been identified as key predictors. Whether this is affected by the location of myocardial ischemia is uncertain. We aimed at comparing the prognostic outlook of patients undergoing MPS according to the site of ischemia. Our institutional database was queried for subjects undergoing MPS, without myocardial necrosis or recent revascularization. We focused on the prognostic impact of location of vessel-related ischemia (VRI) at MPS, distinguishing four mutually exclusive groups: single-VRI involving left anterior descending (LAD), single-VRI not involving LAD, multi-VRI involving LAD, and multi-VRI not involving LAD. The primary outcome was the long-term (>1 year) rate of death or myocardial infarction (D/MI). A total of 13,254 patients were included. Moderate or severe VRI occurred in 2,627 (20%) patients. Clinical outcomes were significantly different among the groups of patients with moderate or severe VRI, including death, cardiac death, non-fatal myocardial infarction or their composites (overall P < .001). Specifically, and excluding subjects undergoing revascularization as first follow-up event, D/MI occurred in 8.4% of patients with single-VRI involving LAD, 5.5% of subjects with single-VRI not involving LAD, 16.5% of those with multi-VRI involving LAD, and 7.3% of patients with multi-VRI not involving LAD (overall P < .001). Even at incremental multivariable Cox proportional analysis, hierarchical VRI was independently associated with an increased risk of D/MI [hazard ratio = 1.17 (1.04-1.08) for each class increment, P = .010]. Location and extent of myocardial ischemia at MPS according to the VRI concept have a hierarchical predictive impact, with multi-VRI involving LAD being significantly and independently more prognostically ominous than other types of VRI.

The Longhorn Array Database (LAD): An Open-Source, MIAME compliant implementation of the Stanford Microarray Database (SMD)

PubMed Central

Killion, Patrick J; Sherlock, Gavin; Iyer, Vishwanath R

2003-01-01

Background The power of microarray analysis can be realized only if data is systematically archived and linked to biological annotations as well as analysis algorithms. Description The Longhorn Array Database (LAD) is a MIAME compliant microarray database that operates on PostgreSQL and Linux. It is a fully open source version of the Stanford Microarray Database (SMD), one of the largest microarray databases. LAD is available at Conclusions Our development of LAD provides a simple, free, open, reliable and proven solution for storage and analysis of two-color microarray data. PMID:12930545

A steady state pressure drop model for screen channel liquid acquisition devices

NASA Astrophysics Data System (ADS)

Hartwig, J. W.; Darr, S. R.; McQuillen, J. B.; Rame, E.; Chato, D. J.

2014-11-01

This paper presents the derivation of a simplified one dimensional (1D) steady state pressure drop model for flow through a porous liquid acquisition device (LAD) inside a cryogenic propellant tank. Experimental data is also presented from cryogenic LAD tests in liquid hydrogen (LH2) and liquid oxygen (LOX) to compare against the simplified model and to validate the model at cryogenic temperatures. The purpose of the experiments was to identify the various pressure drop contributions in the analytical model which govern LAD channel behavior during dynamic, steady state outflow. LH2 pipe flow of LAD screen samples measured the second order flow-through-screen (FTS) pressure drop, horizontal LOX LAD outflow tests determined the relative magnitude of the third order frictional and dynamic losses within the channel, while LH2 inverted vertical outflow tests determined the magnitude of the first order hydrostatic pressure loss and validity of the full 1D model. When compared to room temperature predictions, the FTS pressure drop is shown to be temperature dependent, with a significant increase in flow resistance at LH2 temperatures. Model predictions of frictional and dynamic losses down the channel compare qualitatively with LOX LADs data. Meanwhile, the 1D model predicted breakdown points track the trends in the LH2 inverted outflow experimental results, with discrepancies being due to a non-uniform injection velocity across the LAD screen not accounted for in the model.

[Myocardial imaging in acute myocardial infarction using beta-methyl-p-(123I)-iodophenylpentadecanoic acid: comparison with 201Tl imaging and wall motion].

PubMed

Naruse, H; Itano, M; Kondo, T; Kogame, T; Yamamoto, J; Morita, M; Kawamoto, H; Fukutake, N; Ohyanagi, M; Iwasaki, T

1992-01-01

Myocardial imaging using beta-methyl-p-(123I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial imagings with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (TL) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than TL in the subacute phase, although the uptake of BMIPP correlated with that of TL (tau = 0.82, p less than 0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase (tau = 0.50, p less than 0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and TL alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of TL and WM.

MKLN1 splicing defect in dogs with lethal acrodermatitis

PubMed Central

Bauer, Anina; McEwan, Neil A.; Cadieu, Edouard; André, Catherine; Roosje, Petra; Mellersh, Cathryn; Casal, Margret L.

2018-01-01

Lethal acrodermatitis (LAD) is a genodermatosis with monogenic autosomal recessive inheritance in Bull Terriers and Miniature Bull Terriers. The LAD phenotype is characterized by poor growth, immune deficiency, and skin lesions, especially at the paws. Utilizing a combination of genome wide association study and haplotype analysis, we mapped the LAD locus to a critical interval of ~1.11 Mb on chromosome 14. Whole genome sequencing of an LAD affected dog revealed a splice region variant in the MKLN1 gene that was not present in 191 control genomes (chr14:5,731,405T>G or MKLN1:c.400+3A>C). This variant showed perfect association in a larger combined Bull Terrier/Miniature Bull Terrier cohort of 46 cases and 294 controls. The variant was absent from 462 genetically diverse control dogs of 62 other dog breeds. RT-PCR analysis of skin RNA from an affected and a control dog demonstrated skipping of exon 4 in the MKLN1 transcripts of the LAD affected dog, which leads to a shift in the MKLN1 reading frame. MKLN1 encodes the widely expressed intracellular protein muskelin 1, for which diverse functions in cell adhesion, morphology, spreading, and intracellular transport processes are discussed. While the pathogenesis of LAD remains unclear, our data facilitate genetic testing of Bull Terriers and Miniature Bull Terriers to prevent the unintentional production of LAD affected dogs. This study may provide a starting point to further clarify the elusive physiological role of muskelin 1 in vivo. PMID:29565995

Catheter-induced dissection of the left main coronary artery, the nemesis of an invasive cardiologist A case report and review of the literature.

PubMed

Jain, Deepak; Kurowski, Volkhard; Katus, Hugo A; Richardt, Gert

2002-10-01

An elderly gentleman had a dissection of the left main coronary artery (LMCA) during coronary angiography. There were critical lesions in the left anterior descending (LAD) and left circumflex arteries. Both the LMCA and the LAD lesions were successfully stented in the same sitting. Thereafter the patient remained symptom free and the six-month follow-up angiogram revealed good angioplasty results in both lesions. We report this case for two reasons - first, acute dissection of the LMCA is a rare but devastating complication of selective coronary angiography and the situation becomes graver if the branch vessels have critical stenosis; that this could be managed percutaneously needs to be highlighted, and second, the case offers an opportunity to review literature pertinent to this awesome occurrence in the catheterization laboratory.

ST-depression in right precordial leads with inferior STEMI and occluded right coronary artery: intertwined anatomy and ischemic areas.

PubMed

De Gennaro, Luisa; Brunetti, Natale Daniele; Ruggiero, Massimo; Rutigliano, David; Locuratolo, Nicola; Di Biase, Matteo; Caldarola, Pasquale

2017-10-01

Right coronary artery (RCA) occlusion in inferior acute myocardial infarction is usually heralded by ST-elevation both in inferior and in right precordial leads. We report the case of a 68-year-old male, who presented marked ST-elevation in inferior leads, mirrored by ST-depression in anterior-septal and lateral leads. Right precordial lead electrocardiogram unexpectedly showed ST-depression V1R-V5R leads. Coronary angiography showed mid-left anterior descending (LAD) coronary near-complete occlusion with distal wrapping LAD. Left circumflex artery was not occluded, while RCA was occluded mid tract. The patient was treated with coronary angioplasty on RCA and LAD. Absence of ST-elevation in right precordial leads may be presumably explained by the presence of a large ischemic area distal to mid-LAD near-occlusive stenosis and of a long-wrapping LAD. Complex coronary anatomy and intertwined ischemic areas may underlie apparently discording electrocardiograms.

Performance Gains of Propellant Management Devices for Liquid Hydrogen Depots

NASA Technical Reports Server (NTRS)

Hartwig, Jason W.; McQuillen, John B.; Chato, David J.

2013-01-01

This paper presents background, experimental design, and preliminary experimental results for the liquid hydrogen bubble point tests conducted at the Cryogenic Components Cell 7 facility at the NASA Glenn Research Center in Cleveland, Ohio. The purpose of the test series was to investigate the parameters that affect liquid acquisition device (LAD) performance in a liquid hydrogen (LH2) propellant tank, to mitigate risk in the final design of the LAD for the Cryogenic Propellant Storage and Transfer Technology Demonstration Mission, and to provide insight into optimal LAD operation for future LH2 depots. Preliminary test results show an increase in performance and screen retention over the low reference LH2 bubble point value for a 325 2300 screen in three separate ways, thus improving fundamental LH2 LAD performance. By using a finer mesh screen, operating at a colder liquid temperature, and pressurizing with a noncondensible pressurant gas, a significant increase in margin is achieved in bubble point pressure for LH2 screen channel LADs.

Prenatal diagnosis of LAD-I on cord blood by flowcytometry.

PubMed

Madkaikar, Manisha Rajan; Gupta, Maya; Rao, Meghana; Ghosh, Kanjaksha

2012-12-01

To optimize a simple flowcytometric technique for Prenatal diagnosis (PND) for Leukocyte adhesions defect (LAD-I) on cordocentesis sample at 18 wk gestation. Normal reference ranges for expression of CD18/CD11-integrins in neutrophils and lymphocytes at 18 wk of gestation were established by flowcytometry. PND for LAD-I was then performed on the cordocentesis samples in three 'at risk' pregnancies after ruling out maternal contamination. CD18 and CD11a expression on fetal lymphocytes were found to be the most useful parameters for PND of LAD-I. All the three fetuses tested showed normal expression of CD18/CD11-integrins and thus were unaffected. This was confirmed by testing the cord blood (CB) samples after delivery and normal growth and absence of serious infections on follow-up. Flowcytometry offers a rapid and sensitive technique for PND of LAD-I in the absence of facilities for molecular diagnosis. Obstetricians, even in developing countries with modest facilities, can offer considerable relief for the families.

The Role of Lad Magazines in Priming Men's Chronic and Temporary Appearance-Related Schemata: An Investigation of Longitudinal and Experimental Findings

ERIC Educational Resources Information Center

Aubrey, Jennifer Stevens; Taylor, Laramie D.

2009-01-01

We present a program of research investigating the effects of lad magazines on male body self-consciousness and appearance anxiety. Study 1, based on panel data from undergraduate men, showed that lad magazine exposure in Year 1 predicted body self-consciousness in Year 2. Study 2 was an experiment that showed that men assigned to view objectified…

Thermal Integration of a Liquid Acquisition Device into a Cryogenic Feed System

NASA Technical Reports Server (NTRS)

Hastings, L. J.; Bolshinskiy, L. G.; Schunk, R. G.; Martin, A. K.; Eskridge, R. H.; Frenkel, A.; Grayson, G.; Pendleton, M. L.

2011-01-01

Primary objectives of this effort were to define the following: (1) Approaches for quantification of the accumulation of thermal energy within a capillary screen liquid acquisition device (LAD) for a lunar lander upper stage during periods of up to 210 days on the lunar surface, (2) techniques for mitigating heat entrapment, and (3) perform initial testing, data evaluation. The technical effort was divided into the following categories: (1) Detailed thermal modeling of the LAD/feed system interactions using both COMSOL computational fluid device and standard codes, (2) FLOW-3D modeling of bulk liquid to provide interfacing conditions for the LAD thermal modeling, (3) condensation conditioning of capillary screens to stabilize surface tension retention capability, and (4) subscale testing of an integrated LAD/feed system. Substantial progress was achieved in the following technical areas: (1) Thermal modeling and experimental approaches for evaluating integrated cryogen LAD/feed systems, at both the system and component levels, (2) reduced gravity pressure control analyses, (3) analytical modeling and testing for capillary screen conditioning using condensation and wicking, and (4) development of rapid turnaround testing techniques for evaluating LAD/feed system thermal and fluid integration. A comprehensive effort, participants included a diverse cross section of representatives from academia, contractors, and multiple Marshall Space Flight Center organizations.

Computerized classification of proximal occlusion in the left anterior descending coronary artery.

PubMed

Gregg, Richard E; Nikus, Kjell C; Zhou, Sophia H; Startt Selvester, Ronald H; Barbara, Victoria

2010-01-01

Proximal occlusion within the left anterior descending (LAD) coronary artery in patients with acute myocardial infarction leads to higher mortality than does nonproximal occlusion. We evaluated an automated program to detect proximal LAD occlusion. All patients with suspected acute coronary syndrome (n = 7,710) presenting consecutively to the emergency department of a local hospital with a coronary angiogram–confirmed flow-limiting lesion and notation of occlusion site were included in the study (n = 711). Electrocardiograms (ECGs) that met ST-segment elevation myocardial infarction (STEMI) criteria were included in the training set (n = 183). Paired angiographic location of proximal LAD and ECGs with ST elevation in the anterolateral region were used for the computer program development (n = 36). The test set was based on ECG criteria for anterolateral STEMI only without angiographic reports (n = 162). Tested against 2 expert cardiologists' agreed reading of proximal LAD occlusion, the algorithm has a sensitivity of 95% and a specificity of 82%. The algorithm is designed to have high sensitivity rather than high specificity for the purpose of not missing any proximal LAD in the STEMI population. Our preliminary evaluation suggests that the algorithm can detect proximal LAD occlusion as an additional interpretation to STEMI detection with similar accuracy as cardiologist readers.

Wound Healing Potential of Intermittent Negative Pressure under Limited Access Dressing in Burn Patients: Biochemical and Histopathological Study

PubMed Central

Muguregowda, Honnegowda Thittamaranahalli; Kumar, Pramod; Govindarama, Padmanabha Udupa Echalasara

2018-01-01

BACKGROUND Malondialdehyde (MDA) is an oxidant that causes damage to membranes, DNA, proteins, and lipids at the cellular level. Antioxidants minimize the effects of oxidants and thus help in formation of healthy granulation tissues with higher level of hydroxyproline and total protein. This study compared the effect of limited access dressing (LAD) with conventional closed dressing biochemically and histopathologically. METHODS Seventy-two 12-65 years old burn patients with mean wound size of 14 cm2 were divided to two groups of LAD (n=37), and conventional dressing groups (n=35). Various biochemical parameters were measured in granulation tissue. Histopathological analysis of the granulation tissue was studied too. RESULTS LAD group showed significant increase in hydroxyproline, total protein, GSH, and GPx and decrease in MDA levels compared to conventional dressing group. A significant negative correlation between GSH and MDA was noted in LAD group, but in conventional dressing group there was no significant correlation. A significant negative correlation between GPx and MDA was noticed in LAD group, but in conventional dressing group was not significant. There was a histologically fewer inflammatory cells, increased and well organized extracellular matrix deposit, more angiogenesis in LAD group after 10 days while the difference was significant between the groups. CONCLUSION Our study showed a significant reduction in oxidative stress biomarker of MDA, increase in hydroxyproline, total protein, antioxidants and amount of ECM deposition, number of blood vessels and a decrease in the amount of inflammatory cells and necrotic tissues in LAD group indicating the better healing effect of burn wounds. PMID:29651393

Left anterior descending/right coronary artery as culprit arteries in acute myocardial infarction (n=2011) in changing physical environment, percutaneous coronary intervention data, 2000-2010.

PubMed

Stoupel, Eliyahu; Abramson, Evgeny; Israelevich, Peter

2011-11-02

Percutaneous coronary intervention (PCI) is one of the principal treatments of acute coronary syndrome (ACS), including acute myocardial infarction (AMI). This treatment largely expanded our knowledge on the pathophysiology of AMI and related coronary pathologies. Recent studies found a significant relationship of the timing of ACS with environmental physical activity: solar (SA), geomagnetic (GMA) and cosmic ray (CRA) activity. The aim of this study was to examine if the interrelationship of two principal culprit arteries, left anterior descending (LAD) and right coronary artery (RCA), are involved in the pathogenesis of AMI in different daily levels of GMA and CRA. Patients undergoing PCI for AMI on the day of symptoms of the disease (n=2011, 79.9% males) in the Rabin Medical Center in the years 2000-2010 were studied. The culprit arteries, LAD and RCA, correlated to AMI in zero and I0-IV0 of daily GMA and inversely to GMA related CRA (measured by neutron activity on the earth surface) and their ratio was compared. LAD (45.0%) and RCA (35.7%) were the main culprit arteries in AMI. LAD/RCA ratio increased inversely to GMA (zero=IV0, r=-0.94, p=0.017) and in correlation with daily neutron activity for LAD (r=0.97, p=0.03) and RCA (r=0.95, p=0.04). LAD/RCA ratio was 1 in IV0 of GMA (28% increase) and steadily increased to 1.62 (62% difference) at zero GMA (r=-0.94, p=0.0117), and increasing neutron activity was accompanied by increasing LAD involvement as a culprit artery in AMI. High daily neutron activity and low GMA are accompanied by increasing LAD as a culprit artery in AMI. The possible mechanisms of this finding are discussed.

Optimizing End-to-End Big Data Transfers over Terabits Network Infrastructure

DOE PAGES

Kim, Youngjae; Atchley, Scott; Vallee, Geoffroy R.; ...

2016-04-05

While future terabit networks hold the promise of significantly improving big-data motion among geographically distributed data centers, significant challenges must be overcome even on today's 100 gigabit networks to realize end-to-end performance. Multiple bottlenecks exist along the end-to-end path from source to sink, for instance, the data storage infrastructure at both the source and sink and its interplay with the wide-area network are increasingly the bottleneck to achieving high performance. In this study, we identify the issues that lead to congestion on the path of an end-to-end data transfer in the terabit network environment, and we present a new bulkmore » data movement framework for terabit networks, called LADS. LADS exploits the underlying storage layout at each endpoint to maximize throughput without negatively impacting the performance of shared storage resources for other users. LADS also uses the Common Communication Interface (CCI) in lieu of the sockets interface to benefit from hardware-level zero-copy, and operating system bypass capabilities when available. It can further improve data transfer performance under congestion on the end systems using buffering at the source using flash storage. With our evaluations, we show that LADS can avoid congested storage elements within the shared storage resource, improving input/output bandwidth, and data transfer rates across the high speed networks. We also investigate the performance degradation problems of LADS due to I/O contention on the parallel file system (PFS), when multiple LADS tools share the PFS. We design and evaluate a meta-scheduler to coordinate multiple I/O streams while sharing the PFS, to minimize the I/O contention on the PFS. Finally, with our evaluations, we observe that LADS with meta-scheduling can further improve the performance by up to 14 percent relative to LADS without meta-scheduling.« less

Sequential evaluation of coronary flow patterns after primary angioplasty in acute anterior ST-elevation myocardial infarction predicts recovery of left ventricular systolic function.

PubMed

Sharif, Dawod; Sharif-Rasslan, Amal; Makhoul, Nabeel; Shefer, Arie; Hassan, Amin; Rosenschein, Uri

2014-05-01

Function of the microcirculation after primary percutaneous coronary intervention (PCI) is dynamic and contributes to unpredictability of recovery of left ventricular (LV) systolic function. This study was conducted to evaluate sequential Doppler velocity parameters of the left anterior descending coronary artery (LAD) in predicting recovery of global and regional LV systolic function. Thirty-five consecutive patients, 24 males, age 59 ± 12 years, with acute anterior ST-elevation myocardial infarction (STEMI) who had primary PCI were studied. Thrombolysis in myocardial infarction (TIMI) and myocardial blush grades were evaluated. Transthoracic echocardiographic (TTE) studies, evaluation of left ventricular ejection fraction (LVEF), LAD territory wall-motion score index (WMSI), and sampling of LAD Doppler velocities up to 6 hours post-PCI, 48 hours postprocedure, and predischarge were performed. Thrombolysis in myocardial infarction grade before PCI averaged 0.86 ± 1.19 and post-PCI 2.89 ± 0.32, P < 0.05. Myocardial blush grade before PCI was 0.41 ± 0.98 and after PCI 2.22 ± 0.93, P < 0.05. Diastolic velocity deceleration time (DDT) in the LAD early after PCI was less than 600 ms in 16 subjects. Immediately after PCI, in subjects with DDT > 600 ms, LVEF was 38.5 ± 6% and predischarge 49.2 ± 8.7%, P = 9.77 × 10−5 and LAD-WMSI decreased from 2 ± 0.38 to 1.4 ± 0.48, P = 0.000163. In subjects with DDT < 600 ms LAD-WMSI did not change significantly. Early and minimal LAD-DDT correlated with improvement in LV systolic function, r = 0.6, whereas post-PCI blush grade had lower correlation with LVEF, r = 0.39. Global and regional LV systolic function after PCI in acute anterior MI can be predicted by LAD-DDT better than by post-PCI myocardial blush.

Optimizing End-to-End Big Data Transfers over Terabits Network Infrastructure

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

Kim, Youngjae; Atchley, Scott; Vallee, Geoffroy R.

While future terabit networks hold the promise of significantly improving big-data motion among geographically distributed data centers, significant challenges must be overcome even on today's 100 gigabit networks to realize end-to-end performance. Multiple bottlenecks exist along the end-to-end path from source to sink, for instance, the data storage infrastructure at both the source and sink and its interplay with the wide-area network are increasingly the bottleneck to achieving high performance. In this study, we identify the issues that lead to congestion on the path of an end-to-end data transfer in the terabit network environment, and we present a new bulkmore » data movement framework for terabit networks, called LADS. LADS exploits the underlying storage layout at each endpoint to maximize throughput without negatively impacting the performance of shared storage resources for other users. LADS also uses the Common Communication Interface (CCI) in lieu of the sockets interface to benefit from hardware-level zero-copy, and operating system bypass capabilities when available. It can further improve data transfer performance under congestion on the end systems using buffering at the source using flash storage. With our evaluations, we show that LADS can avoid congested storage elements within the shared storage resource, improving input/output bandwidth, and data transfer rates across the high speed networks. We also investigate the performance degradation problems of LADS due to I/O contention on the parallel file system (PFS), when multiple LADS tools share the PFS. We design and evaluate a meta-scheduler to coordinate multiple I/O streams while sharing the PFS, to minimize the I/O contention on the PFS. Finally, with our evaluations, we observe that LADS with meta-scheduling can further improve the performance by up to 14 percent relative to LADS without meta-scheduling.« less

Stochastic genome-nuclear lamina interactions: modulating roles of Lamin A and BAF.

PubMed

Kind, Jop; van Steensel, Bas

2014-01-01

The nuclear lamina (NL) is thought to aid in the spatial organization of interphase chromosomes by providing an anchoring platform for hundreds of large genomic regions named lamina associated domains (LADs). Recently, a new live-cell imaging approach demonstrated directly that LAD-NL interactions are dynamic and in part stochastic. Here we discuss implications of these new findings and introduce Lamin A and BAF as potential modulators of stochastic LAD positioning.

A Structure Memory for Data Flow Computers

DTIC Science & Technology

1977-09-01

with a FET+ before the result is sent to the destination cells. If one of those cells is a SELECT that issues a FET- to reduce the refe- ence count, the...it.in a lAD packet through lADO . Since a reference count scheme is used for recovering unused cells, the controller watches for words whose reference

Chronic nitric oxide synthase inhibition blunts endothelium-dependent function of conduit coronary arteries, not arterioles

PubMed Central

Ingram, David G.; Newcomer, Sean C.; Price, Elmer M.; Eklund, Kevin E.; McAllister, Richard M.; Laughlin, M. Harold

2009-01-01

Current literature suggests that chronic nitric oxide synthase (NOS) inhibition has differential effects on endothelium-dependent dilation (EDD) of conduit arteries vs. arterioles. Therefore, we hypothesized that chronic inhibition of NOS would impair EDD of porcine left anterior descending (LAD) coronary arteries but not coronary arterioles. Thirty-nine female Yucatan miniature swine were included in the study. Animals drank either tap water or water with NG-nitro-L-arginine methyl ester (L-NAME; 100 mg/l), resulting in control and chronic NOS inhibition (CNI) groups, respectively. Treatment was continued for 1–3 mo (8.3 ± 0.6 mg · kg−1 · day−1). In vitro EDD of coronary LADs and arterioles was assessed via responses to ADP (LADs only) and bradykinin (BK), and endothelium-independent function was assessed via responses to sodium nitroprusside (SNP). Chronic NOS inhibition diminished coronary artery EDD to ADP and BK. Incubating LAD rings with L-NAME decreased relaxation responses of LADs from control pigs but not from CNI pigs such that between-group differences were abolished. Neither indomethacin (Indo) nor sulfaphenazole incubation significantly affected relaxation responses of LAD rings to ADP or BK. Coronary arteries from CNI pigs showed enhanced relaxation responses to SNP. In contrast to coronary arteries, coronary arterioles from CNI pigs demonstrated preserved EDD to BK and no increase in dilation responses to SNP. L-NAME, Indo, and L-NAME + Indo incubation did not result in significant between-group differences in arteriole dilation responses to BK. These results suggest that although chronic NOS inhibition diminishes EDD of LAD rings, most likely via a NOS-dependent mechanism, it does not affect EDD of coronary arterioles. PMID:17259441

Comparative antifungal efficacy of light-activated disinfection and octenidine hydrochloride with contemporary endodontic irrigants.

PubMed

Eldeniz, Ayce Unverdi; Guneser, Mehmet Burak; Akbulut, Makbule Bilge

2015-02-01

The aim of this study was to evaluate the antifungal effects of light-activated disinfection (LAD) in comparison with contemporary root canal irrigation solutions: sodium hypochlorite and 2% chlorhexidine gluconate and a new wound antiseptic, octenidine hydrochloride. Seventy extracted teeth having single root canals were contaminated with Candida albicans for 14 days. The samples were divided into five experimental (n = 10) and two control (positive and negative) groups (n = 10): (1) LAD with toluidine blue O, (2) octenidine hydrochloride (OCT), (3) 2.5% sodium hypochlorite (2.5% NaOCl), (4) 5.25% sodium hypochlorite (5.25% NaOCl) and (5) 2% chlorhexidine. Five millilitres of each test solution was applied for 3 min, and irradiation time used for LAD was 30 s. After treatment, the dentin chips were collected from inner canal walls into vials containing phosphate buffered saline, vortexed, serially diluted, seeded on Tryptic Soy Agar plates and incubated (37 °C, 48 h). The number of colony-forming units was then counted. Differences between LAD group and positive control group were statistically significant (P < 0.05). All Candida cells were totally eliminated in root canals irrigated with OCT, 2.5% NaOCl, 5.25% NaOCl and 2% chlorhexidine groups (CFU = 0). Within the limitations of this ex vivo study, LAD had minimal antimicrobial effect on C. albicans when used 30 s, and further modifications in LAD protocol are required to improve its antifungal capability. A new wound antiseptic, octenidine hydrochloride, demonstrated better potential than LAD in elimination of Candida albicans cells and may be a promising alternative to NaOCl and chlorhexidine solutions in future.

Epidemiology of Intracranial and Extracranial Large Artery Stenosis in a Population-Based Study of Stroke in the Middle East.

PubMed

Saber, Hamidreza; Amiri, Amin; Thrift, Amanda G; Stranges, Saverio; Bavarsad Shahripour, Reza; Farzadfard, Mohammad T; Mokhber, Naghmeh; Behrouz, Réza; Azarpazhooh, Mahmoud Reza

2017-01-01

Intracranial large-artery disease (LAD) is a predominant vascular lesion found in patients with stroke of Asian, African, and Hispanic origin, whereas extracranial LAD is more prevalent among Caucasians. These patterns are not well-established in the Middle East. We aimed to characterize the incidence, risk factors, and long-term outcome of LAD strokes in a Middle-Eastern population. The Mashhad Stroke Incidence Study is a community-based study that prospectively ascertained all cases of stroke among the 450,229 inhabitants of Mashhad, Iran between 2006 and 2007. Ischemic strokes were classified according to the TOAST criteria. Duplex-ultrasonography (98.6%), MR-angiography (8.3%), CT-angiography (11%), and digital-subtraction angiography (9.7%) were performed to identify involvements. Vessels were considered stenotic when the lumen was occluded by >50%. We identified 72 cases (15.99 per 100,000) of incident LAD strokes (mean age 67.6 ± 11.7). Overall, 77% had extracranial LAD (58% male, mean age 69.8 ± 10.3; 50 [89%] carotid vs. 6 [11%] vertebral artery), and the remaining 23% (56% male, mean age 60.2 ± 13.4; 69% anterior-circulation stenosis) had intracranial LAD strokes. We were unable to detect differences in case-fatality between extracranial (1-year: 28.6%; 5-year: 59.8%) and intracranial diseases (1-year: 18.8%; 5-year: 36.8%; log-rank; p = 0.1). Extracranial carotid stenosis represents the majority of LAD strokes in this population. Thus, public health strategies may best be developed in such a way that they are targeted toward the risk factors that contribute to extracranial stenosis. © 2017 S. Karger AG, Basel.

Online versus offline spatiotemporal image correlation (STIC) M-mode for the evaluation of cardiac longitudinal annular displacement in fetal growth restriction.

PubMed

Tanis, Jozien C; Mohammed, Nuruddin; Bennasar, Mar; Martinez, Josep Maria; Bijnens, Bart; Crispi, Fatima; Gratacos, Eduard

2018-07-01

Our first aim was to compare online M-mode with offline spatiotemporal image correlation (STIC) M-mode for assessing longitudinal annular displacement (LAD) in growth-restricted fetuses (FGR). Our second aim was to compare LAD measures of FGR cases with controls. Prospective study including 40 FGR cases (defined estimated fetal weight and birth weight <10th centile) and 72 normally grown fetuses matched to cases by gestational age at scan. LAD was measured with online M-mode and offline STIC M-mode at the left and right ventricular free walls and septum in all fetuses. FGR cases had a significant decrease in LAD by STIC in all sites as compared to controls (e.g. right LAD in FGR mean 6.7 mm (SD 1.2) versus controls 7.2 mm (1.2), p = .033). There was a non-significant trend for lower values in FGR when using online M-mode (e.g. right LAD in FGR 6.9 mm (1.5) versus controls 7.4 mm (1.5), p = .084). STIC M-mode seems a better method than online M-mode for detecting subtle changes in myocardial motion. STIC presents more precise results and allows an ideal placement of the M-mode arrow. These results confirm previous data suggesting decreased longitudinal motion in FGR.

Fluid Acquisition and Resupply Experiments on Space Shuttle Flights STS-53 and STS-57

NASA Technical Reports Server (NTRS)

Dominick, S. M.; Tegart, J. R.; Driscoll, S. L.; Sledd, J. D.; Hastings, L. J.

2011-01-01

The Fluid Acquisition and Resupply Experiment (FARE) program, managed by the Marshall Space Flight Center Space Propulsion Branch with Martin Marietta Civil Space and Communications as the contractor, consisted of two flights designated FARE I and FARE II. FARE I flew in December 1992 on STS-53 with a screen channel liquid acquisition device (LAD) and FARE II flew in June 1993 on STS-57 with a vane-type LAD. Thus, the FARE I and II flights represent the two basic LAD categories usually considered for in-space fluid management. Although both LAD types have been used extensively, the usefulness of the on-orbit data has been constrained by the lack of experimentation beyond predicted performance limits, including both propellant fill and expulsion. Therefore, the FARE tests were designed to obtain data that would satisfy two primary objectives: (1) Demonstrate the performance of the two types of LADs, screen channel and vane, and (2) support the anchoring of analytical models. Both flights were considered highly successful in meeting these two primary objectives.

Simulated full-waveform lidar compared to Riegl VZ-400 terrestrial laser scans

NASA Astrophysics Data System (ADS)

Kim, Angela M.; Olsen, Richard C.; Béland, Martin

2016-05-01

A 3-D Monte Carlo ray-tracing simulation of LiDAR propagation models the reflection, transmission and ab- sorption interactions of laser energy with materials in a simulated scene. In this presentation, a model scene consisting of a single Victorian Boxwood (Pittosporum undulatum) tree is generated by the high-fidelity tree voxel model VoxLAD using high-spatial resolution point cloud data from a Riegl VZ-400 terrestrial laser scanner. The VoxLAD model uses terrestrial LiDAR scanner data to determine Leaf Area Density (LAD) measurements for small volume voxels (20 cm sides) of a single tree canopy. VoxLAD is also used in a non-traditional fashion in this case to generate a voxel model of wood density. Information from the VoxLAD model is used within the LiDAR simulation to determine the probability of LiDAR energy interacting with materials at a given voxel location. The LiDAR simulation is defined to replicate the scanning arrangement of the Riegl VZ-400; the resulting simulated full-waveform LiDAR signals compare favorably to those obtained with the Riegl VZ-400 terrestrial laser scanner.

The SIRIUS mixed analog-digital ASIC developed for the LOFT LAD and WFM instruments

NASA Astrophysics Data System (ADS)

Cros, A.; Rambaud, D.; Moutaye, E.; Ravera, L.; Barret, D.; Caïs, P.; Clédassou, R.; Bodin, P.; Seyler, J. Y.; Bonzo, A.; Feroci, M.; Labanti, C.; Evangelista, Y.; Favre, Y.

2014-07-01

We report on the development and characterization of the low-noise, low power, mixed analog-digital SIRIUS ASICs for both the LAD and WFM X-ray instruments of LOFT. The ASICs we developed are reading out large area silicon drift detectors (SDD). Stringent requirements in terms of noise (ENC of 17 e- to achieve an energy resolution on the LAD of 200 eV FWHM at 6 keV) and power consumption (650 μW per channel) were basis for the ASICs design. These SIRIUS ASICs are developed to match SDD detectors characteristics: 16 channels ASICs adapted for the LAD (970 microns pitch) and 64 channels for the WFM (145 microns pitch) will be fabricated. The ASICs were developed with the 180nm mixed technology of TSMC.

Detection of a numeric value predictive of increased dose to left anterior descending coronary artery (LAD) in radiotherapy of breast cancer.

PubMed

Di Franco, R; Ravo, V; Nieddu, V; Crispo, A; Falivene, S; Giugliano, F M; Argenone, A; Borzillo, V; Cammarota, F; Muto, P

2016-01-01

We have evaluated thoracic conformation of patients in order to derive a numeric value predictive of an increased dose to left anterior descending coronary artery (LAD), critical structure for the development of late radio induced cardiac morbidity. We have evaluated 91 patients (36-88 years) affected by breast cancer stage I-II (Tis-T1-2 N0-1), undergoing adjuvant radiotherapy with conventional fractionation. For each patient on CT images was measured the distance between the back face of the sternum (manubrium) and the anterior face of body of the corresponding vertebra (a), and the distance measured on the line at 45° between the vertebral body of the same vertebra and the back face of the rib corresponding (b). The a/b ratio showed values between 0.626 and 1.123. We used the median value (0.821) as cut-off to divide the patients in two groups. We calculated in both groups: Volume (Vol) heart, Vol LAD with an expansion of 0.6 mm; Dmean LAD (Gy); Dmax LAD (Gy); V10-V20-V30 (%) LAD and we correlated these values with parametric and non-parametric tests. The Pearson test has showed a statistically significant correlation between Vol breast and V10, V20, V30 with borderline significance (p = 0.006; p = 0.02; p = 0.05). The data were confirmed by testing non-parametric Kendall (tau = 0.004; tau = 0.015; tau = 0.016) and Spearman (rho = 0.003; rho = 0.016; rho = 0.015). We conducted categorizing into quartiles of breast volume and evaluated the correlation with a/b. We have found a significative correlation (p = 0.01) between small Vol breast (≤660.23 cc) and a/b < 0.0821 and greater Vol breast (>660.23 cc) with a/b > 0.0821. From the evaluation of the distribution of V10 in the two groups taking account of the Dmean ≤5 or >5 significance was found with a/b; Chi square 0.009 (0.01). Values ≤5 were observed in women with a/b < 0.0821. Values >5 in women with a/b > 0.0821. The geometric conformity of chest thorax considering a/b and the value of 0.0821 can reveals an important parameter in the selection of patients suitable for radiation therapy on left breast in order to evaluate the risk of late cardiac events. This consideration during treatment planning can change the technique or the set-up allowing the development of a customized plan.

SU-C-BRF-01: Correlation of DIBH Breath Hold Amplitude with Dosimetric Sparing of Heart and Left Anterior Descending Artery in Left Breast Radiotherapy

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

Kim, Taeho; Reardon, Kelli; Sukovich, Kaitlyn

Purpose: A 7.4% increase in major coronary events per 1 Gy increase in mean heart dose has been reported from the population-based analysis of radiation-induced cardiac toxicity following treatment of left sided breast cancer. Deep inhalation breath-hold (DIBH) is clinically utilized to reduce radiation dose to heart and left anterior descending artery (LAD). We investigated the correlation of dose sparing in heart and LAD with internal DIBH amplitude to develop a quantitative predictive model for expected dose to heart and LAD based on internal breath hold amplitude. Methods: A treatment planning study (Prescription Dose = 50 Gy) was performed onmore » 50 left breast cancer patients underwent DIBH whole breast radiotherapy. Two CT datasets, free breathing (FB) and DIBH, were utilized for treatment planning and for determination of the internal anatomy DIBH amplitude (difference between sternum position at FB and DIBH). The heart and LAD dose between FB and DIBH plans was compared and dose to the heart and LAD as a function of breath hold amplitude was determined. Results: Average DIBH amplitude using internal anatomy was 13.9±4.2 mm. The DIBH amplitude-mean dose reduction correlation is 20%/5mm (0.3 Gy/5mm) for the heart and 18%/5mm (1.1 Gy/5mm) for LAD. The correlation with max dose reduction is 12%/5mm (3.8 Gy/5mm) for the heart and 16%/5mm (3.2 Gy/5mm) for LAD. We found that average dose reductions to LAD from 6.0±6.5 Gy to 2.0±1.6 Gy with DIBH (4.0 Gy reduction: -67%, p < 0.001) and average dose reduction to the heart from 1.3±0.7 Gy to 0.7±0.2 Gy with DIBH (0.6 Gy reduction: -46%, p < 0.001). That suggests using DIBH may reduce the risk of the major coronary event for left sided breast cancer patients. Conclusion: The correlation between breath hold amplitude and dosimetric sparing suggests that dose sparing linearly increases with internal DIBH amplitude.« less

Long-Term Outcomes of Stenting the Proximal Left Anterior Descending Artery in the PROTECT Trial.

PubMed

Roguin, Ariel; Camenzind, Edoardo; Kerner, Arthur; Beyar, Rafael; Boersma, Eric; Mauri, Laura; Steg, Ph Gabriel; Wijns, William

2017-03-27

This study sought to compare the outcomes of patients undergoing drug-eluting stent implantation according to lesion location within or outside the proximal left anterior descending (LAD) artery. Proximal LAD artery involvement is considered uniquely in revascularization guidelines. The impact of LAD lesion location on long-term outcomes after revascularization is poorly understood in context of current percutaneous coronary intervention and medical therapy. Among 8,709 patients enrolled in PROTECT (Patient Related Outcomes with Endeavor Versus Cypher Stenting Trial), a multicenter percutaneous coronary intervention trial, we compared the outcomes of 2,534 patients (29.1%) (3,871 lesions [31.5%]) with stents implanted in the proximal LAD to 6,172 patients (70.9%) (8,419 lesions [68.5%]) with stents implanted outside the proximal LAD. At the 4-year follow-up, death rates were the same (5.8% vs. 5.8%; p > 0.999), but more myocardial infarctions occurred in the proximal LAD group (6.2% vs. 4.9%; p = 0.015). The rate of clinically driven target vessel failure (TVF) (14.8% vs. 13.5%; p = 0.109), major adverse cardiac event(s) (MACE) (15.0% vs. 13.7%; hazard ratio: 1.1; 95% confidence interval: 0.97 to 1.31; p = 0.139), and stent thrombosis (2.1% vs. 2.0%; p = 0.800) were similar. Drug-eluting stent type had no interaction with MACE or TVF. In multivariate analysis, the proximal LAD was a predictor of myocardial infarction (p = 0.038) but not of TVF (p = 0.149) or MACE (p = 0.069). In this study of contemporary percutaneous coronary intervention, proximal LAD location was associated with higher rates of myocardial infarction during the long-term follow-up, but there were no differences in stent thrombosis, death, TVF, or overall MACE. This finding may suggest that, in the drug-eluting stent era, proximal LAD no longer confers a different prognosis than other lesion sites. (Randomized Study Comparing Endeavor With Cypher Stents [PROTECT]; NCT00476957). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

The impact of hybrid coronary revascularization on hospital costs and reimbursements.

PubMed

Halkos, Michael E; Ford, Lauren; Peterson, Dane; Bluestein, Sheryl M; Liberman, Henry A; Kilgo, Patrick; Puskas, John D; Guyton, Robert A; Chowdhury, Ritam

2014-05-01

Hybrid coronary revascularization (HCR) combines a minimally invasive, left internal mammary artery-left anterior descending coronary artery (LAD) bypass with percutaneous intervention of non-LAD vessels for patients with multivessel coronary disease. The financial implications of HCR have not been compared with off-pump coronary artery bypass (OPCAB) through sternotomy. The contribution margin is a fiduciary calculation (best hospital payment estimate--total variable costs) used by hospitals to determine fiscal viability of services. From 2010 to 2011, 26 Medicare patients underwent HCR at a single United States institution and were compared with 28 randomly selected, contemporaneous Medicare patients undergoing multivessel OPCAB. All HCR patients underwent a robotic-assisted, sternal-sparing, off-pump, left internal mammary artery-LAD anastomosis plus percutaneous intervention to non-LAD vessels. A linear regression model was used to compare fiscal and utilization outcomes of HCR to OPCAB adjusted for hospital length of stay and The Society of Thoracic Surgeons Predicted Risk of Mortality score. On regression analysis controlling for overall length of stay and Predicted Risk of Mortality score, the contribution margin (+$8,771, p<0.0001) was greater for HCR than for OPCAB. Despite higher total cost for HCR compared with OPCAB (+$7,026, p=0.001), the total variable cost (+$2,281, p=0.07) was not significantly different. Best payment estimates (+11,031, p<0.0001) and Medicare reimbursements (+$8,992, p=0.002) were higher for HCR than for OPCAB, and there was a reduction in blood transfusion (-1.5 units, p<0.0001), ventilator time (-10 hours, p=0.001), and postoperative length of stay (-1.2 days, p=0.002) for the HCR group. Compared with OPCAB, HCR results in a greater contribution margin for hospitals. This may result from higher reimbursement as well as improved resource utilization postoperatively, which may offset more expensive procedural costs associated with HCR. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Algorithms for Port-of-Entry Inspection

DTIC Science & Technology

2007-05-29

Devdatt Lad, Rutgers University, Center for Advanced Information Processing Mingyu Li, Rutgers University, Statistics Francesco Longo, University of...Industrial and Systems Engineering graduate student Devdatt Lad, Rutgers University, Electrical & Computer Engineering, graduate student Mingyu Li

Velocity Vector Field Visualization of Flow in Liquid Acquisition Device Channel

NASA Technical Reports Server (NTRS)

McQuillen, John B.; Chao, David F.; Hall, Nancy R.; Zhang, Nengli

2012-01-01

A capillary flow liquid acquisition device (LAD) for cryogenic propellants has been developed and tested in NASA Glenn Research Center to meet the requirements of transferring cryogenic liquid propellants from storage tanks to an engine in reduced gravity environments. The prototypical mesh screen channel LAD was fabricated with a mesh screen, covering a rectangular flow channel with a cylindrical outlet tube, and was tested with liquid oxygen (LOX). In order to better understand the performance in various gravity environments and orientations at different liquid submersion depths of the screen channel LAD, a series of computational fluid dynamics (CFD) simulations of LOX flow through the LAD screen channel was undertaken. The resulting velocity vector field visualization for the flow in the channel has been used to reveal the gravity effects on the flow in the screen channel.

Constrained release of lamina-associated enhancers and genes from the nuclear envelope during T-cell activation facilitates their association in chromosome compartments

PubMed Central

de las Heras, Jose I.; Czapiewski, Rafal; Sivakumar, Aishwarya; Kerr, Alastair R.W.; Schirmer, Eric C.

2017-01-01

The 3D organization of the genome changes concomitantly with expression changes during hematopoiesis and immune activation. Studies have focused either on lamina-associated domains (LADs) or on topologically associated domains (TADs), defined by preferential local chromatin interactions, and chromosome compartments, defined as higher-order interactions between TADs sharing functionally similar states. However, few studies have investigated how these affect one another. To address this, we mapped LADs using Lamin B1–DamID during Jurkat T-cell activation, finding significant genome reorganization at the nuclear periphery dominated by release of loci frequently important for T-cell function. To assess how these changes at the nuclear periphery influence wider genome organization, our DamID data sets were contrasted with TADs and compartments. Features of specific repositioning events were then tested by fluorescence in situ hybridization during T-cell activation. First, considerable overlap between TADs and LADs was observed with the TAD repositioning as a unit. Second, A1 and A2 subcompartments are segregated in 3D space through differences in proximity to LADs along chromosomes. Third, genes and a putative enhancer in LADs that were released from the periphery during T-cell activation became preferentially associated with A2 subcompartments and were constrained to the relative proximity of the lamina. Thus, lamina associations influence internal nuclear organization, and changes in LADs during T-cell activation may provide an important additional mode of gene regulation. PMID:28424353

Role of bacteria in leukocyte adhesion deficiency-associated periodontitis.

PubMed

Hajishengallis, George; Moutsopoulos, Niki M

2016-05-01

Leukocyte adhesion deficiency Type I (LAD-I)-associated periodontitis is an aggressive form of inflammatory bone loss that has been historically attributed to lack of neutrophil surveillance of the periodontal infection. However, this form of periodontitis has proven unresponsive to antibiotics and/or mechanical removal of the tooth-associated biofilm. Recent studies in LAD-I patients and relevant animal models have shown that the fundamental cause of LAD-I periodontitis involves dysregulation of a granulopoietic cytokine cascade. This cascade includes interleukin IL-23 (IL-23) and IL-17 that drive inflammatory bone loss in LAD-I patients and animal models and, moreover, foster a nutritionally favorable environment for bacterial growth and development of a compositionally unique microbiome. Although the lack of neutrophil surveillance in the periodontal pockets might be expected to lead to uncontrolled bacterial invasion of the underlying connective tissue, microbiological analyses of gingival biopsies from LAD-I patients did not reveal tissue-invasive infection. However, bacterial lipopolysaccharide was shown to translocate into the lesions of LAD-I periodontitis. It is concluded that the bacteria serve as initial triggers for local immunopathology through translocation of bacterial products into the underlying tissues where they unleash the dysregulated IL-23-IL-17 axis. Subsequently, the IL-23/IL-17 inflammatory response sustains and shapes a unique local microbiome which, in turn, can further exacerbate inflammation and bone loss in the susceptible host. Copyright © 2015 Elsevier Ltd. All rights reserved.

The influence of side branch stenosis on fractional flow reserve assessment of the main branch in a swine model.

PubMed

Oh, Jun-Hyok; Song, Seunghwan; Kim, Changhoon; Kim, Jeongsu; Sup Park, Jin; Won Lee, Hye; Hyun Choi, Jung; Cheol Lee, Han; Soo Cha, Kwang; Jong Hong, Taek

2017-02-01

The aim of this study was to explore the effect of one stenosis in a daughter artery on the fractional flow reserve (FFR) of another stenosis parallels in side branch. The impact of one stenosis on the FFR of another parallel stenosis has not been evaluated. The proximal segments of the left anterior descending (LAD) and left circumflex (LCX) arteries were exposed and encircled with a Teflon pledget complex in seven swine (55-70 kg). Five degrees of stenosis (to approximate angiographic diameter stenoses of 0%, 25%, 50%, 75%, and 100%) were made by tightening the pledgets. FFR was evaluated simultaneously in the LAD and the LCX with two pressure wires in each coronary artery. A mixed-effects linear model was used to evaluate the association between the FFR values. A total of 115 paired FFR values were obtained. The FFR of the LAD and LCX were not significantly associated with each other (F = 0.237 and P = 0.627 for the LCX FFR to predict the LAD FFR; F = 0.541 and P = 0.463 for the LAD FFR to predict the LCX FFR). The individual FFR values of each parallel stenosis in the LAD and the LCX were not significantly influenced by each other. This relationship was independent of the mean aortic pressure and heart rate. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Early clinical and angiographic outcome of the pedicled right internal thoracic artery graft to the left anterior descending artery.

PubMed

Al-Ruzzeh, Sharif; George, Shane; Bustami, Mahmoud; Nakamura, Koki; Ilsley, Charles; Amrani, Mohamed

2002-05-01

The left internal thoracic artery (LITA) graft to the left anterior descending (LAD) artery became the gold standard graft in coronary surgery. Subsequently, the right internal thoracic artery (RITA) graft was increasingly used. However, there is still some debate about the optimal way of using this conduit. The aim of the present study was to assess our experience in grafting the pedicled RITA graft to LAD in 212 consecutive patients. The records of 212 consecutive patients who underwent isolated coronary artery bypass grafting with the pedicled RITA graft to the LAD artery at Harefield Hospital between January 1998 and May 2001 were retrospectively reviewed. We approached the last 35 consecutive patients to obtain an angiographic control group. All 35 patients (16.5%) consented and, before discharge, underwent angiography to look at the quality of anastomoses and the patency of grafts. Successful catheterization and engagement of the RITA grafts was performed in 32 patients. Angiography showed that 32/32 (100%) of the RITA grafts were widely patent with excellent flow. The distal anastomoses of these RITA grafts were also satisfactory. There were no deaths among the study patients. Our results show that the use of the pedicled RITA graft to the LAD artery provides a good early clinical and angiographic outcome, and suggests that the pedicled RITA graft to the LAD artery is a good alternative to the pedicled LITA graft to the LAD artery.

Drag reducing polymers improve coronary flow reserve through modulation of capillary resistance.

PubMed

Pacella, John J; Kameneva, Marina V; Villanueva, Flordeliza S

2009-01-01

We have shown that drag-reducing polymers (DRP) reduce microvascular resistance and improve myocardial perfusion during coronary stenosis. We used myocardial contrast echocardiography (MCE) and mathematical modeling to define the DRP microvascular effects. A non-flow-limiting left anterior descending (LAD) stenosis was created in 8 dogs. Intramyocardial blood volume, RBC velocity and flow in the LAD and circumflex (CX) beds were obtained from MCE at baseline, and in hyperemia, stenosis, hyperemia + stenosis, and hyperemia + stenosis + DRP. Microvascular resistances were calculated from a lumped-parameter model. During stenosis + hyperemia, LAD bed microvascular resistance increased (p<0.015), and capillary volume (p<0.002) and red cell velocity (p<0.0004) decreased relative to baseline. With DRP, during stenosis and hyperemia, LAD bed microvascular resistance decreased (p<0.04); there was an increase in capillary volume (p<0.007), RBC velocity (p<0.006), and flow (p<0.05). Decreased model-computed capillary resistance accounted for the reduction in LAD bed resistance after DRP. We conclude that DRP improve flow reserve during coronary stenosis by modulating capillary resistance. Primary modification of the rheological properties of blood to affect capillary resistance is a novel approach for the treatment of acute coronary syndromes.

Screening anti-allergic components of Astragali Radix using LAD2 cell membrane chromatography coupled online with UHPLC-ESI-MS/MS method.

PubMed

Lv, Yanni; Sun, Yueming; Fu, Jia; Kong, Liyun; Han, Shengli

2017-02-01

Huangqi (Astragali Radix), a traditional Chinese herb, is widely used in clinical therapy in China. In addition, an anti-allergic effect of constituents in Huangqi has been reported in the scientific literature. In the present study, cell membrane chromatography coupled online with UHPLC-ESI-MS/MS method was developed to screen, analyze and identify the anti-allergic components of Huangqi. The Laboratory of Allergic Disease 2 (LAD2) cell was used to establish cell membrane chromatography, which was combined with UHPLC-ESI-MS/MS. The coupled system was then used to screen anti-allergic components from Huangqi. Effects of active components were verified by histamine release assay. A component retained on the LAD2 cell membrane chromatography was identified as formononetin. Bioactivity of formononetin was investigated by histamine release assay in LAD2 cells, and it was found that formononetin could inhibit histamine release in a dose-dependent manner from 1 to 100 μm. The LAD2 cell membrane chromatography online with UHPLC-ESI-MS/MS method is an effective technique for screening the anti-allergic components of Huangqi. Copyright © 2016 John Wiley & Sons, Ltd.

Increased levels of the long noncoding RNA, HOXA-AS3, promote proliferation of A549 cells.

PubMed

Zhang, Hongyue; Liu, Ying; Yan, Lixin; Zhang, Min; Yu, Xiufeng; Du, Wei; Wang, Siqi; Li, Qiaozhi; Chen, He; Zhang, Yafeng; Sun, Hanliang; Tang, Zhidong; Zhu, Daling

2018-06-13

Many long noncoding RNAs (lncRNAs) have been identified as powerful regulators of lung adenocarcinoma (LAD). However, the role of HOXA-AS3, a novel lncRNA, in LAD is largely unknown. In this study, we showed that HOXA-AS3 was significantly upregulated in LAD tissues and A549 cells. After knockdown of HOXA-AS3, cell proliferation, migration, and invasion were inhibited. Xenografts derived from A549 cells transfected with shRNA/HOXA-AS3 had significantly lower tumor weights and smaller tumor volumes. We also demonstrated that HOXA-AS3 increased HOXA6 mRNA stability by forming an RNA duplex. In addition, HOXA6 promoted cell proliferation, migration, and invasion in vitro. Using a RNA pull-down assay, we found that HOXA-AS3 bonded with NF110, which regulated the cell localization of HOXA-AS3. Moreover, histone acetylation was involved in upregulation of HOXA-AS3. These results demonstrate that HOXA-AS3 was activated in LAD and supported cancer cell progression. Therefore, inhibition of HOXA-AS3 could be an effective targeted therapy for patients with LAD.

Comparison of sequential left internal thoracic artery grafting and separate left internal thoracic artery and venous grafting : A 5-year follow-up.

PubMed

Wendt, D; Schmidt, D; Wasserfuhr, D; Osswald, B; Thielmann, M; Tossios, P; Kühl, H; Jakob, H; Massoudy, P

2010-09-01

The superiority of left internal thoracic artery (LITA) grafting to the left anterior descending artery (LAD) is well established. Patency rates of 80%-90% have been reported at 10-year follow-up. However, the superiority of sequential LITA grafting has not been proven. Our aim was to compare patency rates after sequential LITA grafting to a diagonal branch and the LAD with patency rates of LITA grafting to the LAD and separate vein grafting to a diagonal branch. A total of 58 coronary artery bypass graft (CABG) patients, operated on between 01/2000 and 12/2002, underwent multi-slice computed tomography (MSCT) between 2006 and 2008. Of these patients, 29 had undergone sequential LITA grafting to a diagonal branch and to the LAD ("Sequential" Group), while in 29 the LAD and a diagonal branch were separately grafted with LITA and vein ("Separate" Group). Patencies of all anastomoses were investigated. Mean follow-up was 1958±208 days. The patency rate of the LAD anastomosis was 100% in the Sequential Group and 93% in the Separate Group (p=0.04). The patency rate of the diagonal branch anastomosis was 100% in the Sequential Group and 89% in the Separate Group (p=0.04). Mean intraoperative flow on LITA graft was not different between groups (69±8ml/min in the Sequential Group and 68±9ml/min in the Separate Group, p=n.s.). Patency rates of both the LAD and the diagonal branch anastomoses were higher after sequential arterial grafting compared with separate arterial and venous grafting at 5-year follow-up. This indicates that, with regard to the antero-lateral wall of the left ventricle, there is an advantage to sequential arterial grafting compared with separate arterial and venous grafting.

Clinical and Financial Impact of Ordering an Echocardiogram in Children with Left Axis Deviation on Their Electrocardiogram.

PubMed

Ravi, Prasad; Ashwath, Ravi; Strainic, James; Li, Hong; Steinberg, Jon; Snyder, Christopher

2016-01-01

Left axis deviation (LAD) on the electrocardiogram (ECG) is associated with congenital heart disease (CHD), prompting the clinician to order further testing when evaluating a patient with this finding. The purpose is to (1) compare the physical examination (PE) by a pediatric cardiologist to echocardiogram (ECHO) findings in patients with LAD on resting ECG and (2) assess cost of performing ECHO on all patients with LAD on ECG. An IRB approved, retrospective cohort study was performed on patients with LAD (QRS axis ≥0° to -90°) on ECG between 01/02 and 12/12. age >0.25 and <18 years, non-postoperative, and PE and ECHO by pediatric cardiologist. A decision tree model analyzed cost of ECHO in patients with LAD and normal/abnormal PE. Cost of complete ECHO ($239.00) was obtained from 2014 Medicare reimbursement rates. A total of 146 patients met inclusion criteria with 46.5% (68) having normal PE and ECHO, 1.4% (2) having normal PE and abnormal ECHO, 47.3% (69) having abnormal PE and ECHO, and 4.8% (7) having an abnormal PE and normal ECHO. Sensitivity and specificity of PE for detecting abnormalities in this population was 97% and 90%. Positive and negative predictive value of PE was 91% and 97.5%. In patients with normal PE, the cost to identify an ECHO abnormality was $8365, and $263 for those with abnormal PE. In presence of LAD on ECG, the sensitivity, specificity, and positive and negative predictive values of PE by a pediatric cardiologist are excellent at identifying CHD. Performing an ECHO on patients with LAD on ECG is only cost effective in the presence of an abnormal PE. In the presence of normal PE, there is a possibility of missing incidental structural cardiac disease in approximately 2% if an ECHO is not performed. © 2015 Wiley Periodicals, Inc.

Marsh canopy leaf area and orientation calculated for improved marsh structure mapping

USGS Publications Warehouse

Ramsey, Elijah W.; Rangoonwala, Amina; Jones, Cathleen E.; Bannister, Terri

2015-01-01

An approach is presented for producing the spatiotemporal estimation of leaf area index (LAI) of a highly heterogeneous coastal marsh without reliance on user estimates of marsh leaf-stem orientation. The canopy LAI profile derivation used three years of field measured photosynthetically active radiation (PAR) vertical profiles at seven S. alterniflora marsh sites and iterative transform of those PAR attenuation profiles to best-fit light extinction coefficients (KM). KM sun zenith dependency was removed obtaining the leaf angle distribution (LAD) representing the average marsh orientation and the LAD used to calculate the LAI canopy profile. LAI and LAD reproduced measured PAR profiles with 99% accuracy and corresponded to field documented structures. LAI and LAD better reflect marsh structure and results substantiate the need to account for marsh orientation. The structure indexes are directly amenable to remote sensing spatiotemporal mapping and offer a more meaningful representation of wetland systems promoting biophysical function understanding.

Mechanisms of nuclear lamina growth in interphase.

PubMed

Zhironkina, Oxana A; Kurchashova, Svetlana Yu; Pozharskaia, Vasilisa A; Cherepanynets, Varvara D; Strelkova, Olga S; Hozak, Pavel; Kireev, Igor I

2016-04-01

The nuclear lamina represents a multifunctional platform involved in such diverse yet interconnected processes as spatial organization of the genome, maintenance of mechanical stability of the nucleus, regulation of transcription and replication. Most of lamina activities are exerted through tethering of lamina-associated chromatin domains (LADs) to the nuclear periphery. Yet, the lamina is a dynamic structure demonstrating considerable expansion during the cell cycle to accommodate increased number of LADs formed during DNA replication. We analyzed dynamics of nuclear growth during interphase and changes in lamina structure as a function of cell cycle progression. The nuclear lamina demonstrates steady growth from G1 till G2, while quantitative analysis of lamina meshwork by super-resolution microscopy revealed that microdomain organization of the lamina is maintained, with lamin A and lamin B microdomain periodicity and interdomain gap sizes unchanged. FRAP analysis, in contrast, demonstrated differences in lamin A and B1 exchange rates; the latter showing higher recovery rate in S-phase cells. In order to further analyze the mechanism of lamina growth in interphase, we generated a lamina-free nuclear envelope in living interphase cells by reversible hypotonic shock. The nuclear envelope in nuclear buds formed after such a treatment initially lacked lamins, and analysis of lamina formation revealed striking difference in lamin A and B1 assembly: lamin A reassembled within 30 min post-treatment, whereas lamin B1 did not incorporate into the newly formed lamina at all. We suggest that in somatic cells lamin B1 meshwork growth is coordinated with replication of LADs, and lamin A meshwork assembly seems to be chromatin-independent process.

Change of heart dimensions and function during pregnancy in goats.

PubMed

Szaluś-Jordanow, Olga; Czopowicz, Michał; Witkowski, Lucjan; Moroz, Agata; Mickiewicz, Marcin; Frymus, Tadeusz; Markowska-Daniel, Iwona; Bagnicka, Emilia; Kaba, Jarosław

2018-03-08

The study aimed to evaluate the effect of pregnancy on heart diameters and function in goats. Transthoracic echocardiography of 12 female dairy goats of two Polish regional breeds was performed. A Mindray M7 diagnostic ultrasound system with Phased Array transducer was used. Simultaneously, electrocardiography was recorded. All animals were examined four times - at mating season, at the end of the first trimester, at the end of the second trimester and just before kidding. Eleven measurements were taken each time: aortic and left atrial diameter (AoD and LAD), right and left ventricular internal diameter in diastole (RVIDd and LVIDd), left ventricular internal diameter in systole (LVIDs), inter-ventricular septum thickness in diastole and systole (IVSd and IVSd) and left ventricular posterior wall in diastole and systole (LVPWd and LVPWs), maximum left and right ventricular outflow tract velocity (RVOT Vmax and LVOT Vmax). Nine consecutive measurements were derived: the ratio of the left atrial diameter to the aortic diameter (AoD/LAD), left ventricular fractional shortening (FS%), left ventricular ejection fraction (EF%), maximum outflow tract pressure gradients (RVOT PGmax and LVOT PGmax), left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume (LVESV), stroke volume (SV) and cardiac output (CO). HR, LAD, LVPWs, IVSs increased significantly in the first trimester. AoD and RVIDd were significantly higher around parturition. LVIDd, FS%, EF%, SV and CO rose both in the first and third trimester. No measurement decreased during pregnancy. The study confirms that pregnancy causes changes in the heart size and functioning. Copyright © 2018. Published by Elsevier Ltd.

Constrained release of lamina-associated enhancers and genes from the nuclear envelope during T-cell activation facilitates their association in chromosome compartments.

PubMed

Robson, Michael I; de Las Heras, Jose I; Czapiewski, Rafal; Sivakumar, Aishwarya; Kerr, Alastair R W; Schirmer, Eric C

2017-07-01

The 3D organization of the genome changes concomitantly with expression changes during hematopoiesis and immune activation. Studies have focused either on lamina-associated domains (LADs) or on topologically associated domains (TADs), defined by preferential local chromatin interactions, and chromosome compartments, defined as higher-order interactions between TADs sharing functionally similar states. However, few studies have investigated how these affect one another. To address this, we mapped LADs using Lamin B1-DamID during Jurkat T-cell activation, finding significant genome reorganization at the nuclear periphery dominated by release of loci frequently important for T-cell function. To assess how these changes at the nuclear periphery influence wider genome organization, our DamID data sets were contrasted with TADs and compartments. Features of specific repositioning events were then tested by fluorescence in situ hybridization during T-cell activation. First, considerable overlap between TADs and LADs was observed with the TAD repositioning as a unit. Second, A1 and A2 subcompartments are segregated in 3D space through differences in proximity to LADs along chromosomes. Third, genes and a putative enhancer in LADs that were released from the periphery during T-cell activation became preferentially associated with A2 subcompartments and were constrained to the relative proximity of the lamina. Thus, lamina associations influence internal nuclear organization, and changes in LADs during T-cell activation may provide an important additional mode of gene regulation. © 2017 Robson et al.; Published by Cold Spring Harbor Laboratory Press.

Left Axis Deviation in Children Without Previously Known Heart Disease.

PubMed

Schneider, Andrew E; Cannon, Bryan C; Johnson, Jonathan N; Ackerman, Michael J; Wackel, Philip L

2018-02-01

Left axis deviation (LAD) discovered in children via electrocardiogram (ECG) is uncommon but can be associated with heart disease (HD). The optimal diagnostic approach in a seemingly healthy child with LAD is unclear. We sought to better stratify which patients with LAD but without previously known HD may warrant additional workup. A retrospective chart review was performed to identify patients ≥1 to <18 years of age with LAD (QRS frontal plane axis 0 to -90) on an ECG between January 2002 and December 2014. Patients with known HD before their initial ECG were excluded. Overall, 296 patients were identified ( n = 181 [61%] male; mean age: 10.8 ± 4.6 years; mean QRS axis: -24 ± 22°). An echocardiogram was performed in 158 (53%) patients, with 24 (15%) having HD. Compared with those with an echocardiogram but without HD ( n = 134), patients with HD had a more negative mean QRS axis (-42 vs -27°; P = .002) and were more likely to have a QRS axis ≤-42° (58% vs 26%; P = .003), ECG chamber enlargement or hypertrophy (38% vs 5%; P < .0001), and abnormal cardiac physical examination findings (75% vs 8%; P < .0001). LAD discovered in isolation in the asymptomatic pediatric patient may not necessitate further cardiovascular investigation. Clinicians should consider obtaining an echocardiogram in patients with LAD and ECG cardiac chamber enlargement or hypertrophy, a QRS axis ≤-42°, and/or the presence of abnormal cardiac physical examination findings. Copyright © 2018 by the American Academy of Pediatrics.

Association of functional magnetic resonance imaging indices with postoperative language outcomes in patients with primary brain tumors.

PubMed

Kundu, Bornali; Penwarden, Amy; Wood, Joel M; Gallagher, Thomas A; Andreoli, Matthew J; Voss, Jed; Meier, Timothy; Nair, Veena A; Kuo, John S; Field, Aaron S; Moritz, Chad; Meyerand, M Elizabeth; Prabhakaran, Vivek

2013-04-01

Functional MRI (fMRI) has the potential to be a useful presurgical planning tool to treat patients with primary brain tumor. In this study the authors retrospectively explored relationships between language-related postoperative outcomes in such patients and multiple factors, including measures estimated from task fMRI maps (proximity of lesion to functional activation area, or lesion-to-activation distance [LAD], and activation-based language lateralization, or lateralization index [LI]) used in the clinical setting for presurgical planning, as well as other factors such as patient age, patient sex, tumor grade, and tumor volume. Patient information was drawn from a database of patients with brain tumors who had undergone preoperative fMRI-based language mapping of the Broca and Wernicke areas. Patients had performed a battery of tasks, including word-generation tasks and a text-versus-symbols reading task, as part of a clinical fMRI protocol. Individually thresholded task fMRI activation maps had been provided for use in the clinical setting. These clinical imaging maps were used to retrospectively estimate LAD and LI for the Broca and Wernicke areas. There was a relationship between postoperative language deficits and the proximity between tumor and Broca area activation (the LAD estimate), where shorter LADs were related to the presence of postoperative aphasia. Stratification by tumor location further showed that for posterior tumors within the temporal and parietal lobes, more bilaterally oriented Broca area activation (LI estimate close to 0) and a shorter Wernicke area LAD were associated with increased postoperative aphasia. Furthermore, decreasing LAD was related to decreasing LI for both Broca and Wernicke areas. Preoperative deficits were related to increasing patient age and a shorter Wernicke area LAD. Overall, LAD and LI, as determined using fMRI in the context of these paradigms, may be useful indicators of postsurgical outcomes. Whereas tumor location may influence postoperative deficits, the results indicated that tumor proximity to an activation area might also interact with how the language network is affected as a whole by the lesion. Although the derivation of LI must be further validated in individual patients by using spatially specific statistical methods, the current results indicated that fMRI is a useful tool for predicting postoperative outcomes in patients with a single brain tumor.

Nonmyeloablative Conditioning with Busulfan before Matched Littermate Bone Marrow Transplantation Results in Reversal of the Disease Phenotype in Canine Leukocyte Adhesion Deficiency

PubMed Central

Sokolic, Robert A.; Bauer, Thomas R.; Gu, Yu-Chen; Hai, Mehreen; Tuschong, Laura M.; Burkholder, Tanya; Colenda, Lyn; Bacher, John; Starost, Matthew F.; Hickstein, Dennis D.

2005-01-01

Leukocyte adhesion deficiency (LAD)–1, a primary immunodeficiency disease caused by molecular defects in the leukocyte integrin CD18 molecule, is characterized by recurrent, life-threatening bacterial infections. Myeloablative hematopoietic stem cell transplantation is the only curative treatment for LAD-1. Recently, canine LAD (CLAD) has been shown to be a valuable animal model for the preclinical testing of nonmyeloablative transplantation regimens for the treatment of children with LAD-1. To develop new allogeneic transplantation approaches for LAD-1, we assessed a nonmyeloablative conditioning regimen consisting of busulfan as a single agent before matched littermate allogeneic bone marrow transplantation in CLAD. Three CLAD dogs received busulfan 10 mg/kg intravenously before infusion of matched littermate bone marrow, and all dogs received posttransplantation immunosuppression with cyclosporin A and mycophenolate mofetil. Initially, all 3 dogs became mixed chimeras, and levels of donor chimerism sufficient to reverse the CLAD phenotype persisted in 2 animals. The third dog maintained donor microchimerism with an attenuated CLAD phenotype. These 3 dogs have all been followed up for at least 1 year after transplantation. These results indicate that a nonmyeloablative conditioning regimen with chemotherapy alone is capable of generating stable mixed chimerism and reversal of the disease phenotype in CLAD. PMID:16182176

Bioresorbable vascular scaffolds for LMCA with double vessel disease under IVUS guidance.

PubMed

Kasturi, Sridhar; Vilvanathan, Vinoth Kumar

2015-12-01

An 80-year-old male patient, presented with chest pain. ECG showed ST elevation in leads V2 to V4 and T wave inversion in leads V2-V6. Check angiogram revealed ostial LMCA 70% lesion & mid-LAD 90% lesion and LCX proximal 80% lesion. Predilatation of LMCA lesion was done with 2.0 × 12 mm NC Trek balloon and the LAD lesion with 2.0 × 12 mm and 2.5 × 08 mm (NC Trek balloons). Prestenting IVUS (Intravascular ultrasound) was done with Atlantis SR pro 40 MHz 3.6 Fr catheter. IVUS showed the LAD to have a minimal lumen area of 2.6 sq mm with 90% fibrotic plaque and a vessel size of 2.5mm and the LMCA to have a minimal lumen area of 8.8 sq mm with 70% fibrotic plaque and vessel size of 3.8mm. Mid-LAD stenting was done with 2.5 × 28 mm Absorb Stent (BVS). Predilatation of LCX lesion was done with 2.5 × 08 mm NC Trek balloon. Then stenting was performed with 3.0 × 28 mm Absorb Stent (BVS). Check angiogram showed edge dissection proximal to the BVS Stent which was covered with 3.0 × 12 mm Xience Xpedtion Stent (DES). Then LMCA Stenting was done with 3.5 × 12 mm Absorb Stent. Post dilatation was done with 4.0 × 08 mm NC Trek balloon. Post Stenting LMCA - LAD IVUS was done. LMCA and LAD Stents were well opposed without any dissection or residual stenosis. TIMI III Flow was achieved in the final results. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Summation and Cancellation Effects on QRS and ST-Segment Changes Induced by Simultaneous Regional Myocardial Ischemia.

PubMed

Vives-Borrás, Miquel; Jorge, Esther; Amorós-Figueras, Gerard; Millán, Xavier; Arzamendi, Dabit; Cinca, Juan

2018-01-01

Simultaneous ischemia in two myocardial regions is a potentially lethal clinical condition often unrecognized whose corresponding electrocardiographic (ECG) patterns have not yet been characterized. Thus, this study aimed to determine the QRS complex and ST-segment changes induced by concurrent ischemia in different myocardial regions elicited by combined double occlusion of the three main coronary arteries. For this purpose, 12 swine were randomized to combination of 5-min single and double coronary artery occlusion: Group 1: left Circumflex (LCX) and right (RCA) coronary arteries ( n = 4); Group 2: left anterior descending artery (LAD) and LCX ( n = 4) and; Group 3: LAD and RCA ( n = 4). QRS duration and ST-segment displacement were measured in 15-lead ECG. As compared with single occlusion, double LCX+RCA blockade induced significant QRS widening of about 40 ms in nearly all ECG leads and magnification of the ST-segment depression in leads V1-V3 (maximal 228% in lead V3, p < 0.05). In contrast, LAD+LCX or LAD+RCA did not induce significant QRS widening and markedly attenuated the ST-segment elevation in precordial leads (maximal attenuation of 60% in lead V3 in LAD+LCX and 86% in lead V5 in LAD+RCA, p < 0.05). ST-segment elevation in leads V7-V9 was a specific sign of single LCX occlusion. In conclusion, concurrent infero-lateral ischemia was associated with a marked summation effect of the ECG changes previously elicited by each single ischemic region. By contrast, a cancellation effect on ST-segment changes with no QRS widening was observed when the left anterior descending artery was involved.

Officer Accessions Flow Model

DTIC Science & Technology

2011-07-31

officers select their own BOLC-B dates completely divorced of their unit assignment and that unit’s ARFORGEN cycle. We reschedule all FY10 cohort LTs...for BOLC-B based upon unit priority based upon number of days until LAD. Rescheduling all FY10 cohort LTs for BOLC-B based upon unit priority...with specialty branches (doctors, lawyers, nurses , chaplains, etc) which have minimal representation in BCT-level units.  DCs are not generally

Look-Ahead Distance of a fiber probe used to assist neurosurgery: Phantom and Monte Carlo study

NASA Astrophysics Data System (ADS)

Qian, Zhiyu; Victor, Sunder S.; Gu, Yueqing; Giller, Cole A.; Liu, Hanli

2003-08-01

A short-separation, optical reflectance probe has been developed to assist the neurosurgeon in functional neurosurgery for accurate localization of the surgical target. Because of the scattering nature of tissue, the optical probe has a "Look Ahead Distance" (LAD), at which the measured optical reflectance starts to "see" or "sense" the underlying brain structure due to the difference in light scattering of tissue. To quantify the LAD, 2-layer laboratory phantoms have been developed to mimic gray and white matter of the brain, and Monte Carlo simulations have been also used to confirm the experimental findings. Based on both the laboratory and simulation results, a quantitative empirical equation is developed to express the LAD as a function of scattering coefficient of the measured tissue for a 400-micron-diameter fiber probe. The quantified LAD of the probe is highly desirable so as to improve the spatial resolution of the probe for better surgery guidance.

Recovery of distal coronary flow reserve in LAD and LCx after Y-Graft intervention assessed by transthoracic echocardiography

PubMed Central

2010-01-01

Background Y- graft (Y-G) is a graft formed by the Left Internal Mammary Artery (LIMA) connected to the Left Anterior Descending Artery (LAD) and by a free Right Internal Mammary Artery (RIMA) connected to LIMA and to a Marginal artery of Left Circumflex Artery (LCx). Aim of the work was to study the flow of this graft during a six months follow-up to assess whether the graft was able to meet the request of all the left coronary circulation, and to assess whether it could be done by evaluation of coronary flow reserve (CFR). Methods In 13 consecutive patients submitted to Y-G (13 men), CFR was measured in distal LAD and in distal LCx from 1 week after , every two months, up to six months after operation (a total of 8 tests for each patient) by means of transthoracic echocardiography (TTE) and Adenosine infusion (140 mcg/kg/min for 3-6 min). A Sequoia 256, Acuson-Siemens, was used. Contrast was used when necessary (Levovist 300 mg/ml solution at a rate of 0,5-1 ml/min). Max coronary flow diastolic velocity post-/pre-test ≥2 was considered normal CFR. Results Coronary arteriography revealed patency of both branches of Y-G after six months. Accuracy of TTE was 100% for LAD and 85% for LCx. Feasibility was 100% for LAD and 85% for LCx. CFR improved from baseline in LAD (2.21 ± 0.5 to 2.6 ± 0.5, p = 0.03) and in LCx (1.7 ± 1 to 2.12 ± 1, p = 0.05). CFR was under normal at baseline in 30% of patients vs 8% after six months in LAD (p = 0.027), and in 69% of patients vs 30% after six months in LCx (p = 0.066). Conclusion CFR in Y-G is sometimes reduced in both left territories postoperatively but it improves at six months follow-up. A follow-up can be done non-invasively by TTE and CFR evaluation. PMID:20716357

An integrated array of microfluidic oxygenators as a neonatal lung assist device: in vitro characterization and in vivo demonstration.

PubMed

Rochow, Niels; Manan, Asmaa; Wu, Wen-I; Fusch, Gerhard; Monkman, Shelley; Leung, Jennifer; Chan, Emily; Nagpal, Dipen; Predescu, Dragos; Brash, John; Selvaganapathy, Ponnambalam Ravi; Fusch, Christoph

2014-10-01

A miniaturized oxygenator device that is perfused like an artificial placenta via the umbilical vessels may have significant potential to save the lives of newborns with respiratory insufficiency. Recently we presented the concept of an integrated modular lung assist device (LAD) that consists of stacked microfluidic single oxygenator units (SOUs) and demonstrated the technical details and operation of SOU prototypes. In this article, we present a LAD prototype that is designed to accommodate the different needs of term and preterm infants by permitting changing of the number of parallel-stacked microfluidic SOUs according to the actual body weight. The SOUs are made of polydimethylsiloxane, arranged in parallel, and connected though 3D-printed polymeric interconnects to form the LAD. The flow characteristics and the gas exchange properties were tested in vitro using human blood. We found that the pressure drop of the LAD increased linearly with flow rate. Gas exchange rates of 2.4-3.8 μL/min/cm(2) (0.3-0.5 mL/kg/min) and 6.4-10.1 μL/min/cm(2) (0.8-1.3 mL/kg/min) for O2 and CO2 , respectively, were achieved. We also investigated protein adsorption to provide preliminary information on the need for application of anticoagulant coating of LAD materials. Albumin adsorption, as measured by gold staining, showed that surface uptake was evenly distributed and occurred at the monolayer level (>0.2 μg/cm(2) ). Finally, we also tested the LAD under in vivo conditions using a newborn piglet model (body weight 1.65-2.0 kg). First, the effect of an arteriovenous bypass via a carotid artery-to-jugular vein shortcut on heart rate and blood pressure was investigated. Heart rate and mean arterial blood pressure remained stable for extracorporeal flow rates of up to 61 mL/kg/min (101 mL/min). Next, the LAD was connected to umbilical vessels (maximum flow rate of 24 mL/min [10.4 mL/kg/min]), and O2 gas exchange was measured under hypoxic conditions (Fi O2  = 0.15) and was found to be 3.0 μL/min/cm(2) . These results are encouraging and support the feasibility of an artificial placental design for an LAD. Copyright © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

LADS: Optimizing Data Transfers using Layout-Aware Data Scheduling

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

Kim, Youngjae; Atchley, Scott; Vallee, Geoffroy R

While future terabit networks hold the promise of signifi- cantly improving big-data motion among geographically distributed data centers, significant challenges must be overcome even on today s 100 gigabit networks to real- ize end-to-end performance. Multiple bottlenecks exist along the end-to-end path from source to sink. Data stor- age infrastructure at both the source and sink and its in- terplay with the wide-area network are increasingly the bottleneck to achieving high performance. In this paper, we identify the issues that lead to congestion on the path of an end-to-end data transfer in the terabit network en- vironment, and we presentmore » a new bulk data movement framework called LADS for terabit networks. LADS ex- ploits the underlying storage layout at each endpoint to maximize throughput without negatively impacting the performance of shared storage resources for other users. LADS also uses the Common Communication Interface (CCI) in lieu of the sockets interface to use zero-copy, OS-bypass hardware when available. It can further im- prove data transfer performance under congestion on the end systems using buffering at the source using flash storage. With our evaluations, we show that LADS can avoid congested storage elements within the shared stor- age resource, improving I/O bandwidth, and data transfer rates across the high speed networks.« less

Revascularization of Left Coronary System Using a Skeletonized Left Internal Mammary Artery　- Sequential vs. Separate Grafting.

PubMed

Ji, Qiang; Shi, YunQing; Xia, LiMin; Ma, RunHua; Shen, JinQiang; Lai, Hao; Ding, WenJun; Wang, ChunSheng

2017-12-25

To evaluate in-hospital and mid-term outcomes of sequential vs. separate grafting of in situ skeletonized left internal mammary artery (LIMA) to the left coronary system in a single-center, propensity-matched study.Methods and Results:After propensity score-matching, 120 pairs of patients undergoing first scheduled isolated coronary artery bypass grafting (CABG) with in situ skeletonized LIMA grafting to the left anterior descending artery (LAD) territory were entered into a sequential group (sequential grafting of LIMA to the diagonal artery and then to the LAD) or a control group (separate grafting of LIMA to the LAD). The in-hospital and follow-up clinical outcomes and follow-up LIMA graft patency were compared. Both propensity score-matched groups had similar in-hospital and follow-up clinical outcomes. Sequential LIMA grafting was not found to be an independent predictor of adverse events. During a follow-up period of 27.0±7.3 months, 99.1% patency for the diagonal site and 98.3% for the LAD site were determined by coronary computed tomographic angiography after sequential LIMA grafting, both of which were similar with graft patency of separate grafting of in situ skeletonized LIMA to the LAD. Revascularization of the left coronary system using a skeletonized LIMA resulted in excellent in-hospital and mid-term clinical outcomes and graft patency using sequential grafting.

Neuromodulation therapy does not influence blood flow distribution or left-ventricular dynamics during acute myocardial ischemia.

PubMed

Kingma, J G; Linderoth, B; Ardell, J L; Armour, J A; DeJongste, M J; Foreman, R D

2001-08-13

Electrical stimulation of the dorsal aspect of the upper thoracic spinal cord is used increasingly to treat patients with angina pectoris refractory to conventional therapeutic strategies. The purpose of this study was to determine whether spinal cord stimulation (SCS) in dogs affects regional myocardial blood flow and left-ventricular (LV) function before and during transient obstruction of the left anterior descending coronary artery (LAD). In anesthetized dogs, regional myocardial blood flow distribution was determined using radiolabeled microspheres and left-ventricular function was measured by impedance-derived pressure-volume loops. SCS was accomplished by stimulating the dorsal T1-T2 segments of the spinal cord using epidural bipolar electrodes at 90% of motor threshold (MT) (50 Hz, 0.2-ms duration). Effects of 5-min SCS were assessed under basal conditions and during 4-min occlusion of the LAD. SCS alone evoked no change in regional myocardial blood flow or cardiovascular indices. Transient LAD occlusion significantly diminished blood flow within ischemic, but not in non-ischemic myocardial tissue. Left ventricular pressure-volume loops were shifted rightward during LAD occlusion. Cardiac indices were altered similarly during LAD occlusion and concurrent SCS. SCS does not influence the distribution of blood flow within the non-ischemic or ischemic myocardium. Nor does it modify LV pressure-volume dynamics in the anesthetized experimental preparation.

Contribution of starter cultures to the proteolytic process of a fermented non-dried whole muscle ham product.

PubMed

Scannell, Amalia G M; Kenneally, Paul M; Arendt, Elke K

2004-06-01

Porcine longissimus dorsi muscles were cured by brine injection. Curing brine containing 15% (w/v) NaCl, 1.33% (w/v) glucose, 750 ppm sodium nitrite, and appropriate levels of either Lactobacillus sakei LAD, L. sakei LAD plus Kocuria varians FT4 (formally Micrococcus varians), L. sakei LAD plus papain and GDL (glucono-delta-lactone) plus K. varians FT4, was injected to the muscle at a pumping rate 15% w/v. The effect of these treatments on the proteolysis in the ham system was compared to a control ham, produced without starter culture and containing GDL acidulant to control pH and antibiotics to reduce the contribution of background microflora. Hydrolysis of sarcoplasmic and myofibrillar protein fractions was evaluated by SDS-PAGE and reverse phase-HPLC. Hams with different treatments were also investigated for differences in amino acid profile, protein and non-protein nitrogen level, colour, pH, water activity and moisture and microbiological evolution. There was no significant difference in the gross compositional analysis of any of the treatments compared to the control. There was no significant difference (p>0.05) in the protein content, non-protein nitrogen level, SDS-PAGE and free amino acid analysis between the control ham and ham inoculated with proteolytic starter culture. However, it was observed that hams containing starter cultures exhibited decreases in certain peptide fractions and corresponding increases in some free amino acids compared to the uninoculated control. It can be concluded that, while the principle mechanisms resulting in the proteolysis of this non-dried ham product involve the activity of endogeneous cathepsins, the addition of proteolytic starter cultures influence the amino acid profile thereby potentially enhancing the sensorial attributes of the ham. Copyright 2004 Elsevier B.V.

Estimation of infarct size using transthoracic Doppler echocardiographic measurement of coronary flow reserve in infarct related and reference coronary artery.

PubMed

Giga, Vojislav; Dobric, Milan; Beleslin, Branko; Sobic-Saranovic, Dragana; Tesic, Milorad; Djordjevic-Dikic, Ana; Stepanovic, Jelena; Nedeljkovic, Ivana; Artiko, Vera; Obradovic, Vladimir; Seferovic, Petar M; Ostojic, Miodrag

2013-09-20

Patients in chronic phase of myocardial infarction (MI) have decreased coronary flow reserve (CFR) in infarct related artery (IRA) that is proportional to the extent of microvascular/myocardial damage. We proposed a novel model for the assessment of microvascular damage and infarct size using Doppler echocardiography evaluation of CFRs of the IRA (LAD) and reference artery (RCA). Our study included 34 consecutive patients (28 men, mean age 50 ± 11 years) with first anterior STEMI and single vessel disease successfully treated with primary PCI. All patients underwent SPECT MPI for the assessment of infarct size (expressed as a percentage of myocardium with fixed perfusion abnormalities) and CFR evaluation of LAD and RCA. CFR derived percentage of microvascular damage (CFR PMD) was calculated as: CFR PMD=(CFR RCA-CFR LAD)/(CFR RCA-1)×100 (%). CFR PMD correlated significantly with all parameters evaluating the severity of myocardial damage including: peak CK activity (r=0.632, p<0.001), WMSI (r=0.857, p<0.001), ejection fraction (r=-0.820, p<0.001), left ventricular end diastolic (r=0.757, p<0.001) and end systolic volume (r=0.794, p<0.001). Most importantly, CFR PMD (22 ± 17%) correlated significantly with infarct size by SPECT MPI (21 ± 17%) (r=0.874, p<0.001). CFR PMD derived from the proposed model was significantly related to echocardiographic and enzymatic parameters of infarct size, as well as to myocardial damage assessed by SPECT MPI in patients with successfully reperfused first anterior STEMI. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Screen channel liquid acquisition device outflow tests in liquid hydrogen

NASA Astrophysics Data System (ADS)

Hartwig, J. W.; Chato, D. J.; McQuillen, J. B.; Vera, J.; Kudlac, M. T.; Quinn, F. D.

2014-11-01

This paper presents experimental design and test results of the recently concluded 1-g inverted vertical outflow testing of two 325 × 2300 full scale liquid acquisition device (LAD) channels in liquid hydrogen (LH2). One of the channels had a perforated plate and internal cooling from a thermodynamic vent system (TVS) to enhance performance. The LADs were mounted in a tank to simulate 1-g outflow over a wide range of LH2 temperatures (20.3-24.2 K), pressures (100-350 kPa), and flow rates (0.010-0.055 kg/s). Results indicate that the breakdown point is dominated by liquid temperature, with a second order dependence on mass flow rate through the LAD. The best performance is always achieved in the coldest liquid states for both channels, consistent with bubble point theory. Higher flow rates cause the standard channel to break down relatively earlier than the TVS cooled channel. Both the internal TVS heat exchanger and subcooling the liquid in the propellant tank are shown to significantly improve LAD performance.

DNA sequence-dependent compartmentalization and silencing of chromatin at the nuclear lamina.

PubMed

Zullo, Joseph M; Demarco, Ignacio A; Piqué-Regi, Roger; Gaffney, Daniel J; Epstein, Charles B; Spooner, Chauncey J; Luperchio, Teresa R; Bernstein, Bradley E; Pritchard, Jonathan K; Reddy, Karen L; Singh, Harinder

2012-06-22

A large fraction of the mammalian genome is organized into inactive chromosomal domains along the nuclear lamina. The mechanism by which these lamina associated domains (LADs) are established remains to be elucidated. Using genomic repositioning assays, we show that LADs, spanning the developmentally regulated IgH and Cyp3a loci contain discrete DNA regions that associate chromatin with the nuclear lamina and repress gene activity in fibroblasts. Lamina interaction is established during mitosis and likely involves the localized recruitment of Lamin B during late anaphase. Fine-scale mapping of LADs reveals numerous lamina-associating sequences (LASs), which are enriched for a GAGA motif. This repeated motif directs lamina association and is bound by the transcriptional repressor cKrox, in a complex with HDAC3 and Lap2β. Knockdown of cKrox or HDAC3 results in dissociation of LASs/LADs from the nuclear lamina. These results reveal a mechanism that couples nuclear compartmentalization of chromatin domains with the control of gene activity. Copyright © 2012 Elsevier Inc. All rights reserved.

Screen Channel Liquid Acquisition Device Outflow Tests in Liquid Hydrogen

NASA Technical Reports Server (NTRS)

Hartwig, Jason W.; Chato, David J.; McQuillen, J. B.; Vera, J.; Kudlac, M. T.; Quinn, F. D.

2013-01-01

This paper presents experimental design and test results of the recently concluded 1-g inverted vertical outflow testing of two 325x2300 full scale liquid acquisition device (LAD) channels in liquid hydrogen (LH2). One of the channels had a perforated plate and internal cooling from a thermodynamic vent system (TVS) to enhance performance. The LADs were mounted in a tank to simulate 1-g outflow over a wide range of LH2 temperatures (20.3 - 24.2 K), pressures (100 - 350 kPa), and flow rates (0.010 - 0.055 kg/s). Results indicate that the breakdown point is dominated by liquid temperature, with a second order dependence on mass flow rate through the LAD. The best performance is always achieved in the coldest liquid states for both channels, consistent with bubble point theory. Higher flow rates cause the standard channel to break down relatively earlier than the TVS cooled channel. Both the internal TVS heat exchanger and subcooling the liquid in the propellant tank are shown to significantly improve LAD performance.

Directional atherectomy facilitates the interventional procedure and leads to a low rate of recurrent stenosis in left anterior descending and left circumflex artery ostium stenoses: subgroup analysis of the FLEXI‐CUT study

PubMed Central

Dahm, J B; Ruppert, J; Hartmann, S; Vogelgesang, D; Hummel, A; Felix, S B

2006-01-01

Objectives To examine by retrospective analysis of data from the FLEXI‐CUT monocentre registry whether atherectomy can effectively simplify complex stent implantation in ostial bifurcation lesions by reducing the procedure to stenting of the left anterior descending (LAD) or left circumflex (LCX) artery ostium alone. Patients and methods All patients who had been enrolled in the prospective FLEXI‐CUT study (directional atherectomy with adjunctive balloon angioplasty) were retrospectively analysed on the basis of significant LAD or LCX ostial stenosis (⩾ 70% stenosis) deriving from an undiseased left main stem. The primary combined end point was the rate of target lesion revascularisation (TLR) and binary restenosis; secondary end points were procedural success and major adverse cardiac events (MACE) at the six‐month follow up. Results Of 30 patients enrolled with significant LAD or LCX ostium stenosis, 29 were effectively treated with directional atherectomy (96.7% procedural success). All patients underwent single‐vessel stenting procedures of solely the LAD or LCX ostium. At follow up, binary stenosis was 25% (6 of 24), TLR (angiographic plus clinical) 10.3% (3 of 29) and total MACE 6.9% (2 of 29). Conclusions Directional atherectomy with single‐vessel stenting procedures facilitates the interventional treatment of LAD and LCX ostium stenosis, and leads to remarkably low TLR and binary stenosis at follow up. PMID:16449510

M-mode and two-dimensional echocardiographic reference values for three Hungarian dog breeds: Hungarian Vizsla, Mudi and Hungarian Greyhound.

PubMed

Vörös, Károly; Hetyey, Csaba; Reiczigel, Jeno; Czirok, Gábor Nagy

2009-06-01

The aim of the study was to establish normal reference echocardiographic values for three Hungarian dog breeds, and to determine the potential dependence of intracardiac parameters on body weight, age and gender. M-mode and two-dimensional echocardiography were performed on 95 clinically healthy dogs including 45 Hungarian Vizslas, 28 Mudis and 22 Hungarian Greyhounds. Linear intracardiac measurements included interventricular septal thickness (IVS), left ventricular internal diameter (LVID), left ventricular posterior wall thickness (LVPW) both in systole and diastole, as well as left atrial internal diameter (LAD), and aortic diameter (AOD) in early diastole. Fractional shortening (FS), end-diastolic and end-systolic left ventricular volumes (EDV and ESV), as well as LAD:AOD ratio were calculated from the linear parameters. Mean, range and standard deviation of measurements were calculated for each breed. Body weight positively correlated in all three breeds with all left ventricular dimensions, such as IVS d , IVS s , LVID d , LVIDD s , LVPW d and LVPW s parameters. LA values showed positive correlations to body weight in all three breeds. AOD and LA demonstrated a positive correlation with body weight in Hungarian Vizslas and Mudis, whilst the LAD:AOD ratio was related to body weight only in Mudis. Gender did not correlate with any of the measured echocardiographic parameters in any breeds. In Mudis, a positive correlation was found between the LAD: AOD ratio and age, as well as between the LAD: AOD ratio and E point to septal separation (EPSS).

Return of the lysergamides. Part II: Analytical and behavioural characterization of N6 -allyl-6-norlysergic acid diethylamide (AL-LAD) and (2'S,4'S)-lysergic acid 2,4-dimethylazetidide (LSZ).

PubMed

Brandt, Simon D; Kavanagh, Pierce V; Westphal, Folker; Elliott, Simon P; Wallach, Jason; Colestock, Tristan; Burrow, Timothy E; Chapman, Stephen J; Stratford, Alexander; Nichols, David E; Halberstadt, Adam L

2017-01-01

Lysergic acid N,N-diethylamide (LSD) is perhaps one of the most intriguing psychoactive substances known and numerous analogs have been explored to varying extents in previous decades. In 2013, N 6 -allyl-6-norlysergic acid diethylamide (AL-LAD) and (2'S,4'S)-lysergic acid 2,4-dimethylazetidide (LSZ) appeared on the 'research chemicals'/new psychoactive substances (NPS) market in both powdered and blotter form. This study reports the analytical characterization of powdered AL-LAD and LSZ tartrate samples and their semi-quantitative determination on blotter paper. Included in this study was the use of nuclear magnetic resonance (NMR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), low and high mass accuracy electrospray MS(/MS), high performance liquid chromatography diode array detection and GC solid-state infrared analysis. One feature shared by serotonergic psychedelics, such as LSD, is the ability to mediate behavioural responses via activation of 5-HT 2A receptors. Both AL-LAD and LSZ displayed LSD-like responses in male C57BL/6 J mice when employing the head-twitch response (HTR) assay. AL-LAD and LSZ produced nearly identical inverted-U-shaped dose-dependent effects, with the maximal responses occurring at 200 µg/kg. Analysis of the dose responses by nonlinear regression confirmed that LSZ (ED 50  = 114.2 nmol/kg) was equipotent to LSD (ED 50  = 132.8 nmol/kg) in mice, whereas AL-LAD was slightly less potent (ED 50  = 174.9 nmol/kg). The extent to which a comparison in potency can be translated directly to humans requires further investigation. Chemical and pharmacological data obtained from NPS may assist research communities that are interested in various aspects related to substance use and forensic identification. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Return of the lysergamides. Part II: Analytical and behavioural characterization of N6-allyl-6-norlysergic acid diethylamide (AL-LAD) and (2’S,4’S)-lysergic acid 2,4-dimethylazetidide (LSZ)

PubMed Central

Brandt, Simon D.; Kavanagh, Pierce V.; Westphal, Folker; Elliott, Simon P.; Wallach, Jason; Colestock, Tristan; Burrow, Timothy E.; Chapman, Stephen J.; Stratford, Alexander; Nichols, David E.; Halberstadt, Adam L.

2017-01-01

Lysergic N,N-diethylamide (LSD) is perhaps one of the most intriguing psychoactive substances known and numerous analogs have been explored to a varying extent in previous decades. In 2013, N6-allyl-6-norlysergic acid diethylamide (AL-LAD) and (2’S,4’S)-lysergic acid 2,4-dimethylazetidide (LSZ) have appeared on the ‘research chemicals’ / new psychoactive substances (NPS) market in both powdered and blotter form. This study reports the analytical characterization of powdered AL-LAD and LSZ tartrate samples and their semi-quantitative determination on blotter paper. Included in this study was the use of nuclear magnetic resonance spectroscopy, gas chromatography mass spectrometry (MS), low and high-resolution electrospray MS(/MS), high performance liquid chromatography diode array detection and GC solid-state infrared analysis. One feature shared by serotonergic psychedelics, such as LSD, is the ability to mediate behavioral responses via activation of 5-HT2A receptors. Both AL-LAD and LSZ displayed LSD-like responses in male C57BL/6J mice when employing the head-twitch response (HTR) assay. AL-LAD and LSZ produced nearly identical inverted-U-shaped dose-dependent effects, with the maximal responses occurring at 200 µg/kg. Analysis of the dose-responses by nonlinear regression confirmed that LSZ (ED50 = 114.2 nmol/kg) was equipotent to LSD (ED50 = 132.8 nmol/kg) in mice, whereas AL-LAD was slightly less potent (ED50 = 174.9 nmol/kg). The extent to which a comparison in potency can be translated directly to humans requires further investigation. Availability of both chemical and pharmacological data obtained from NPS as they appear on the market provides important data to research communities that are interested in various aspects related substance use and forensic identification. PMID:27265891

Influence of type of aortic valve prosthesis on coronary blood flow velocity.

PubMed

Jelenc, Matija; Juvan, Katja Ažman; Medvešček, Nadja Tatjana Ružič; Geršak, Borut

2013-02-01

Severe aortic valve stenosis is associated with high resting and reduced hyperemic coronary blood flow. Coronary blood flow increases after aortic valve replacement (AVR); however, the increase depends on the type of prosthesis used. The present study investigates the influence of type of aortic valve prosthesis on coronary blood flow velocity. The blood flow velocity in the left anterior descending coronary artery (LAD) and the right coronary artery (RCA) was measured intraoperatively before and after AVR with a stentless bioprosthesis (Sorin Freedom Solo; n = 11) or a bileaflet mechanical prosthesis (St. Jude Medical Regent; n = 11). Measurements were made with an X-Plore epicardial Doppler probe (Medistim, Oslo, Norway) following induction of hyperemia with an adenosine infusion. Preoperative and postoperative echocardiography evaluations were used to assess valvular and ventricular function. Velocity time integrals (VTI) were measured from the Doppler signals and used to calculate the proportion of systolic VTI (SF), diastolic VTI (DF), and normalized systolic coronary blood flow velocities (NSF) and normalized diastolic coronary blood flow velocities (NDF). The systolic proportion of the LAD VTI increased after AVR with the St. Jude Medical Regent prosthesis, which produced higher LAD SF and NSF values than the Sorin Freedom Solo prosthesis (SF, 0.41 ± 0.09 versus 0.29 ± 0.13 [P = .04]; NSF, 0.88 ± 0.24 versus 0.55 ± 0.17 [P = .01]). No significant changes in the LAD velocity profile were noted after valve replacement with the Sorin Freedom Solo, despite a significant reduction in transvalvular gradient and an increase in the effective orifice area. AVR had no effect on the RCA flow velocity profile. The coronary flow velocity profile in the LAD was significantly influenced by the type of aortic valve prosthesis used. The differences in the LAD velocity profile probably reflect differences in valve design and the systolic transvalvular flow pattern.

Regional difference of microcirculation in patients with asymmetric hypertrophic cardiomyopathy: transthoracic Doppler coronary flow velocity reserve analysis.

PubMed

Tesic, Milorad; Djordjevic-Dikic, Ana; Beleslin, Branko; Trifunovic, Danijela; Giga, Vojislav; Marinkovic, Jelena; Petrovic, Olga; Petrovic, Milan; Stepanovic, Jelena; Dobric, Milan; Vukcevic, Vladan; Stankovic, Goran; Seferovic, Petar; Ostojic, Miodrag; Vujisic-Tesic, Bosiljka

2013-07-01

To evaluate, by noninvasive coronary flow velocity reserve (CFVR), whether patients with asymmetric hypertrophic cardiomyopathy (HC), with or without left ventricular outflow tract obstruction, demonstrate significant regional differences of CFVR. We evaluated 61 patients with HC (27 men; mean age 49 ± 16 years), including 20 patients with hypertrophic obstructive cardiomyopathy (HOCM) and 41 patients without obstruction (HCM). The control group included 20 age- and sex-matched subjects. Transthoracic Doppler echocardiography CFVR of the left anterior descending coronary artery (LAD) and the posterior descending coronary artery (PD) were performed, including calculation of relative CFVR as the ratio between CFVR LAD and CFVR PD. Compared with the controls, all the patients with HC had lower CFVR LAD (2.12 ± 0.53 vs 3.34 ± 0.67; P < .001) and CFVR PD (2.29 ± 0.49 vs 3.21 ± 0.65; P < .001). CFVR LAD in HOCM group in comparison with the HCM group was significantly lower (1.93 ± 0.42 vs 2.22 ± 0.55; P = .047), due to higher basal diastolic coronary flow velocities (0.40 ± 0.09 vs 0.33 ± 0.07 m/sec; P = .002), with similar hyperemic diastolic flow velocities (0.71 ± 0.16 vs 0.76 ± 0.19 m/sec; P = .330), respectively. There was no significant difference in CFVR PD between patients with HOCM and those with HCM (2.33 ± 0.46 vs 2.27 ± 0.50; P = .636), respectively. Relative CFVR was lower in the HOCM group compared with the HCM group (0.84 ± 0.16 vs 0.98 ± 0.14; P = .001). By multivariable regression analysis, left ventricular outflow tract gradient was the independent predictor of CFVR LAD (B = -0.24; P = .008) and relative CFVR (B = -0.34; P = .016). CFVR LAD and relative CFVR were significantly lower in patients with HOCM compared with patients with HCM. Regional differences of CFVR are present only in patients with significant left ventricular outflow tract obstruction, which suggests that obstruction per se, by increasing wall stress in basal conditions, leads to higher basal diastolic coronary flow velocities and results in lower CFVR in LAD compared with PD. Copyright © 2013 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

Molecular Characterization of a Lizard Adenovirus Reveals the First Atadenovirus with Two Fiber Genes and the First Adenovirus with Either One Short or Three Long Fibers per Penton

PubMed Central

Pénzes, Judit J.; Menéndez-Conejero, Rosa; Condezo, Gabriela N.; Ball, Inna; Papp, Tibor; Doszpoly, Andor; Paradela, Alberto; Pérez-Berná, Ana J.; López-Sanz, María; Nguyen, Thanh H.; van Raaij, Mark J.; Marschang, Rachel E.; Harrach, Balázs; Benkő, Mária

2014-01-01

ABSTRACT Although adenoviruses (AdVs) have been found in a wide variety of reptiles, including numerous squamate species, turtles, and crocodiles, the number of reptilian adenovirus isolates is still scarce. The only fully sequenced reptilian adenovirus, snake adenovirus 1 (SnAdV-1), belongs to the Atadenovirus genus. Recently, two new atadenoviruses were isolated from a captive Gila monster (Heloderma suspectum) and Mexican beaded lizards (Heloderma horridum). Here we report the full genomic and proteomic characterization of the latter, designated lizard adenovirus 2 (LAdV-2). The double-stranded DNA (dsDNA) genome of LAdV-2 is 32,965 bp long, with an average G+C content of 44.16%. The overall arrangement and gene content of the LAdV-2 genome were largely concordant with those in other atadenoviruses, except for four novel open reading frames (ORFs) at the right end of the genome. Phylogeny reconstructions and plesiomorphic traits shared with SnAdV-1 further supported the assignment of LAdV-2 to the Atadenovirus genus. Surprisingly, two fiber genes were found for the first time in an atadenovirus. After optimizing the production of LAdV-2 in cell culture, we determined the protein compositions of the virions. The two fiber genes produce two fiber proteins of different sizes that are incorporated into the viral particles. Interestingly, the two different fiber proteins assemble as either one short or three long fiber projections per vertex. Stoichiometry estimations indicate that the long fiber triplet is present at only one or two vertices per virion. Neither triple fibers nor a mixed number of fibers per vertex had previously been reported for adenoviruses or any other virus. IMPORTANCE Here we show that a lizard adenovirus, LAdV-2, has a penton architecture never observed before. LAdV-2 expresses two fiber proteins—one short and one long. In the virion, most vertices have one short fiber, but a few of them have three long fibers attached to the same penton base. This observation raises new intriguing questions on virus structure. How can the triple fiber attach to a pentameric vertex? What determines the number and location of each vertex type in the icosahedral particle? Since fibers are responsible for primary attachment to the host, this novel architecture also suggests a novel mode of cell entry for LAdV-2. Adenoviruses have a recognized potential in nanobiomedicine, but only a few of the more than 200 types found so far in nature have been characterized in detail. Exploring the taxonomic wealth of adenoviruses should improve our chances to successfully use them as therapeutic tools. PMID:25056898

Using Calcareous Nannofossil Biostratigraphy to Improve the Identification of the Albian-Cenomanian Boundary

NASA Astrophysics Data System (ADS)

Chin, Shamar; Watkins, David

2017-04-01

Identifying the Albian-Cenomanian boundary has proven to be difficult due to taxonomic discrepancies associated with the foraminifera used to mark this boundary. Thalmaninella globotruncanoides and foraminifera that co-exist at this stratigraphic level are difficult to distinguish due to the presence of transitional forms. As a result, it is important to find other microfossil markers to aid in identifying this boundary. The first appearance datum (FAD) of Calculites anfractus is the secondary calcareous nannofossil marker for the basal Cenomanian; however, C. anfractus is not a reliable marker as it is rare. In addition, holococcoliths do not occur in all oceanic settings because they are more susceptible to dissolution than heterococcoliths. Currently, the last appearance datum (LAD) of Hayesites albiensis and the FAD of Corollithion kennedyi are used to estimate the Albian-Cenomanian boundary. Although these markers are reliable, it is necessary to refine the nannofossil biostratigraphic resolution in this part of the column to improve the accuracy of placing the boundary. Seventy-three smear slides were analyzed from DSDP Sites 137 and 547. Approximately 500 specimens were counted and two additional traverses were scanned for rare species. The data were then analyzed using a probabilistic biostratigraphic method known as RAnking and SCaling (RASC). Lithraphidites eccentricum was previously believed to have an FAD in the middle Cenomanian because it was assigned an age based on its co-occurrence with planktonic foraminifera from the Rotalipora cushmani Zone and Rotalipora appenninica Subzone; however, a taxonomic review later showed that the FAD of L. eccentricum co-occurs with foraminifer Hedbergella libyca, which went extinct shortly after the Albian-Cenomanian boundary. This study corroborates this finding as the FAD of L. eccentricum is observed below the FAD of C. kennedyi (100.45 Ma). The LAD of Gartnerago stenostaurion is another event that was placed in the upper Albian; however, this study shows that G. stenostaurion has its LAD in the lower Cenomanian. The LAD of G. stenostaurion almost coincides with the LAD of Gartnerago chiasta, which is dated at 99.94 Ma. Furthermore,a transitional morphotype between Corollithion signum and C. kennedyi was observed at Site 547 close to the Albian-Cenomanian boundary. These transitional morphotypes exhibit a thick central crossbar and a more hexagonal shape, similar to that of C. kennedyi; however, the morphotype lacks optically split crossbars. This indicates that this is not C. kennedyi. These transitional morphotypes have an LAD before the FAD of C. kennedyi and potentially have biostratigraphic significance. It is important to note that this is a preliminary finding and more localities need to be assessed to determine the extent of its distribution. In addition to the LAD of H. albiensis and the FAD of C. kennedyi, this study proposes using other lower Cenomanian bioevents to improve the resolution in this part of the stratigraphic column. The revised stratigraphic positions of the FAD of L. eccentricum and the LAD of G. stenostaurion as well as the newly identified LAD of the C. kennedyi morphotype should be used in conjunction with other bioevents to better constrain the Albian-Cenomanian boundary.

Effects of Learning Analytics Dashboard: Analyzing the Relations among Dashboard Utilization, Satisfaction, and Learning Achievement

ERIC Educational Resources Information Center

Kim, Jeonghyun; Jo, Il-Hyun; Park, Yeonjeong

2016-01-01

The learning analytics dashboard (LAD) is a newly developed learning support tool for virtual classrooms that is believed to allow students to review their online learning behavior patterns intuitively through the provision of visual information. The purpose of this study was to empirically validate the effects of LAD. An experimental study was…

Single left coronary artery with separate origins of proximal and distal right coronary arteries from left anterior descending and circumflex arteries--a previously undescribed coronary circulation.

PubMed

Kaul, Pankaj; Javangula, Kalyana

2007-04-20

A single left coronary artery with right coronary artery arising from either left main stem (LMS) or left anterior descending artery (LAD) or circumflex artery (Cx) is an extremely rare coronary anomaly. This is the first report of separate origins of proximal and distal RCA from LAD and circumflex arteries respectively in a patient with a single left coronary artery. This 57 year old patient presented with unstable angina and severe stenotic disease of LAD and Cx arteries and underwent urgent successful quadruple coronary artery bypass grafting. The anomalies of right coronary artery in terms of their origin, number and distribution are reviewed.

The risk of coronary artery disease estimated non-invasively in patients with essential hypertension environmentally exposed to cigarette smoke.

PubMed

Gać, Paweł; Jaźwiec, Przemysław; Poręba, Małgorzata; Mazur, Grzegorz; Pawlas, Krystyna; Sobieszczańska, Małgorzata; Poręba, Rafał

2017-12-01

The relationship between environmental exposure of non-smokers to cigarette smoke and the coronary artery calcium scores has not been sufficiently documented. The aim of the study was to identify the relationship between environmental exposure to cigarette smoke and the risk of coronary artery disease (CAD) estimated non-invasively through measurement of coronary artery calcium score by computed tomography in patients with essential hypertension. The study was conducted on 67 patients with essential hypertension, non-smokers environmentally exposed to cigarette smoke (group A) and on 67 patients with essential hypertension, non-smokers not exposed to cigarette smoke (group B), selected using the case to case. Environmental exposure to cigarette smoke was evaluated using a questionnaire. The risk of development of coronary artery disease was estimated non-invasively through measurement of coronary artery calcium score (CA CS ) by computed tomography. Group A was characterised by significantly higher CA CS and left anterior descending (LAD CS ) calcium scores than group B. Compared to group B, group A had significantly higher percentage of patients with significant risk of CAD estimated on the basis of CA CS values, and significantly lower percentage of patients with practically no risk of CAD estimated with the same method. Advanced age, peripheral artery diseases and environmental exposure to cigarette smoke are independent risk factors associated with increased CA CS and LAD CS values. In addition, higher BMI and hypercholesterolemia are independent risk factors for increased values of LAD CS . In patients with essential hypertension environmental exposure to cigarette smoke may result in elevated risk of coronary artery disease estimated non-invasively through measurement of coronary artery calcium score by computed tomography. Copyright © 2017 Elsevier B.V. All rights reserved.

Update of Ablative Fractionated Lasers to Enhance Cutaneous Topical Drug Delivery.

PubMed

Waibel, Jill S; Rudnick, Ashley; Shagalov, Deborah R; Nicolazzo, Danielle M

2017-08-01

Ablative fractional lasers (AFXL) enhance uptake of therapeutics and this newly emerging field is called laser-assisted drug delivery (LAD). This new science has emerged over the past decade and is finding its way into clinical practice. LAD is poised to change how medicine delivers drugs. Topical and systemic application of pharmaceutical agents for therapeutic effect is an integral part of medicine. With topical therapy, the stratum corneum barrier of the skin impairs the ability of drugs to enter the body. The purpose of LAD is to alter the stratum corneum, epidermis, and dermis to facilitate increased penetration of a drug, device, or cell to its respected target. AFXL represents an innovative, non-invasive strategy to overcome the epidermal barrier. LAD employs three steps: (1) breakdown of the skin barrier with a laser, (2) optional use a laser for a therapeutic effect, (3) delivery of the medicine through laser channels to further enhance the therapeutic effect. The advantages of using lasers for drug delivery include the ease of accessibility, the non-invasive aspect, and its effectiveness. By changing the laser settings, one may use LAD to have a drug remain locally within the skin or to have systemic delivery. Many drugs are not intended for use in the dermis and so it has yet to be determined which drugs are appropriate for this technique. It appears this developing technology has the ability to be a new delivery system for both localized and systemic delivery of drugs, cells, and other molecules. With responsible development AFXL-assisted drug delivery may become a new important part of medicine.

Prospective Clinical Trial of Robotically Assisted Endoscopic Coronary Grafting With 1-Year Follow-Up

PubMed Central

Prasad, Sunil M.; Ducko, Christopher T.; Stephenson, Edward R.; Chambers, Charles E.; Damiano, Ralph J.

2001-01-01

Objective To follow up in prospective fashion patients with coronary artery anastomoses completed endoscopically with robotic assistance. The robotic system was evaluated for safety and its effectiveness in completing microsurgical coronary anastomoses. Summary Background Data Recently there has been an interest in using robotics and computers to enhance the surgeon’s ability to perform endoscopic cardiac surgery. This interest has stemmed from the rapid advancement of technology and the desire to make cardiac surgery less invasive. Using traditional endoscopic instruments, it has not been possible to perform coronary surgery. Methods Nineteen patients underwent robotically assisted endoscopic coronary artery bypass grafting of the left internal thoracic artery (LITA) to the left anterior descending artery (LAD). Two robotic instruments and one endoscopic camera were placed through three 5-mm ports. A robotic system was used to construct the LITA–LAD anastomosis. All other required grafts were completed by conventional techniques. Results Seventeen LITA–LAD grafts (89%) had adequate intraoperative flow. The mean LITA–LAD graft flow was 38.5 ± 5 mL/min. At 8 weeks, LITA–LAD grafts were assessed by angiography and showed 100% patency with thrombolysis in myocardial infarction (TIMI) I flow. At a mean follow-up of 17 ± 4.2 months, all patients were NYHA class I and there were no adverse cardiac events. Conclusions The results from the first prospective clinical trial of robotically assisted endoscopic coronary bypass surgery in the United States showed favorable short-term outcomes with no adverse events. Robotic assistance is an enabling technology allowing the performance of endoscopic coronary anastomoses. PMID:11371730

Wide sternal retraction may impede internal mammary artery graft flow and reduce myocardial function during off-pump coronary artery bypass grafting: presentation of two cases

PubMed Central

Espinoza, Andreas; Bergsland, Jacob; Lundblad, Runar; Fosse, Erik

2012-01-01

The internal mammary artery (IMA) is routinely used for grafting of the left anterior descending coronary artery (LAD), providing good flow to the anterior left ventricle (LV) wall. Impeded IMA-to-LAD flow may result in myocardial ischaemia and haemodynamic deterioration. From a study population, we describe two incidents where myocardial ischaemia was observed during off-pump coronary artery bypass surgery (CABG), with a confirmed reduction in the IMA-to-LAD flow in one patient. In patient no. 1, normal IMA flow was assessed by transit-time flow measurement after a complete IMA-to-LAD anastomosis. The anterior LV wall thickening was monitored continuously by epicardial ultrasonic transducers. Normal wall thickening was confirmed after IMA grafting. During a wide sternal opening for circumflex grafting the anterior wall motion displayed an ischaemic pattern, with reduced systolic and increased post-systolic wall thickening. IMA flow was reduced simultaneously. When easing the sternal opening, IMA flow normalized, as did the motion pattern in the anterior LV wall. In patient no. 2, similar changes in wall thickening occurred during a wide sternal opening after IMA-to-LAD grafting. When easing the retractor, the wall thickening normalized. It is important for the surgeon to be aware of this possible cause of myocardial ischaemia, with a risk of subsequent haemodynamic deterioration. This may not only be of great importance during off-pump CABG, but can also be significant for successful weaning from the cardiopulmonary bypass machine. PMID:22499803

Left ventricular ejection fraction and left atrium diameter related to new-onset atrial fibrillation following acute myocardial infarction: a systematic review and meta-analysis.

PubMed

Zeng, Rui-Xiang; Chen, Mao-Sheng; Lian, Bao-Tao; Liao, Peng-Da; Zhang, Min-Zhou

2017-10-06

New-onset atrial fibrillation (NOAF) occurs frequently in patients with acute myocardial infarction (AMI), and is associated with increased subsequent cardiovascular mortality. However, only a few studies directly evaluated the relationship of left ventricular ejection fraction (LVEF) or left atrium diameter (LAD) and NOAF following AMI. MEDLINE ® , EMBASE ® and the Cochrane Library were carried out to find studies until January 2017. Pooled mean difference (MD) and 95% confidence interval (CI) were calculated to evaluate the value of LVEF and LAD in the prediction of NOAF after AMI. We performed sensitivity analyses to explore the potential sources of heterogeneity. Statistical analyses were carried out using the Revman 5.3. We included 10 qualifying studies comprising a total of 708 patients with NOAF and 6785 controls. Overall, decreased LVEF and increased LAD levels had a significant positive association with NOAF in patients with AMI. The MD in the LVEF levels between the patients with and those without NOAF was -4.91 units (95% Cl: -5.70 to -4.12), test for overall effect z-score = 12.18 ( p < 0.00001, I 2 = 35%). Moreover, in a subgroup analysis, the MD for LAD and NOAF was 2.55 units (95% Cl: 1.91 to 3.19), test for overall effect z-score = 7.80 ( p < 0.00001, I 2 = 57%). Our meta-analysis demonstrated that both decreased LVEF and increased LAD levels were associated with greater risk of NOAF following AMI.

Augmenting the antibiofilm efficacy of advanced noninvasive light activated disinfection with emulsified oxidizer and oxygen carrier.

PubMed

George, Saji; Kishen, Anil

2008-09-01

In this study, we tested the hypothesis that the inclusion of an oxidizer and oxygen carrier in the photosensitization formulation would facilitate comprehensive disinfection of matured endodontic biofilm by light-activated disinfection (LAD). Photosensitizing formulations containing methylene blue (MB) and an oxygen carrier alone (perfluorodecahydronaphthalene) (PF1) or in combination with oxidizer (H(2)O(2)) (PF2) or their emulsions formed with triton-X100 (Bio-Rad Laboratories, Hercules, CA) in different proportions (PF3 and PF4) were tested for photochemical properties and damage to the biofilm structure using confocal laser scanning microscopy. Conventional chemomechanical preparation, LAD using MB in water, and LAD using MB in emulsion (PF4) were also conducted on 10-week-old Enterococcus faecalis biofilm within root canals. MB in emulsion (PF4) was overall the most effective photosensitizer formulation for photooxidation, generation of singlet oxygen (p = 0.001), and in disinfecting biofilm bacteria. Advanced noninvasive LAD using a photosensitizer formulation containing oxidizer and oxygen carrier disrupted the biofilm matrix and facilitated comprehensive inactivation of biofilm bacteria. This modified photosensitizer formulation will have potential advantages in endodontic disinfection.

Quantitative Measurement of Dissection Resistance in Intimal and Medial Layers of Human Coronary Arteries

PubMed Central

Wang, Ying; Johnson, John A.; Spinale, Francis G.; Sutton, Michael A.; Lessner, Susan M.

2014-01-01

The left anterior descending (LAD) coronary artery is the most frequently involved vessel in coronary artery dissection, a cause of acute coronary syndrome or sudden cardiac death. The biomechanical mechanisms underlying arterial dissection are not well understood. This study investigated the dissection properties of LAD specimens harvested from explanted hearts at the time of cardiac transplantation, from patients with primary dilated cardiomyopathy (n=12). Using a previously validated approach uniquely modified for these human LAD specimens, we quantified the local energy release rate, G, within different arterial layers during experimental dissection events (tissue tearing). Results show that the mean values of G during arterial dissection within the intima and within the media in human LADs are 20.7±16.5 J/m2 and 10.3±5.0 J/m2, respectively. The difference in dissection resistance between tearing events occurring within the intima and within the media is statistically significant. Our data fall in the same order of magnitude as most previous measurements of adhesive strength in other human arteries, with the differences in measured values of G within the layers most likely due to histologically observed differences in the structure and composition of arterial layers. PMID:24729631

Capillary Liquid Acquisition Device Heat Entrapment

NASA Technical Reports Server (NTRS)

Bolshinskiy, L. G.; Hastings, L. J.; Statham, G.; Turpin, J. B.

2007-01-01

Cryogenic liquid acquisition devices (LADs) for space-based propulsion interface directly with the feed system, which can be a significant heat leak source. Further, the accumulation of thermal energy within LAD channels can lead to the loss of subcooled propellant conditions and result in feed system cavitation during propellant outflow. Therefore, the fundamental question addressed by this program was: To what degree is natural convection in a cryogenic liquid constrained by the capillary screen meshes envisioned for LADs? Testing was first conducted with water as the test fluid, followed by LN2 tests. In either case, the basic experimental approach was to heat the bottom of a cylindrical column of test fluid to establish stratification patterns measured by temperature sensors located above and below a horizontal screen barrier position. Experimentation was performed without barriers, with screens, and with a solid barrier. The two screen meshes tested were those typically used by LAD designers, 200x1400 and 325x2300, both with Twill Dutch Weave. Upon consideration of both the water and LN2 data, it was concluded that heat transfer across the screen meshes was dependent upon barrier thermal conductivity and that the capillary screen meshes were impervious to natural convection currents.

Cryogenic Capillary Screen Heat Entrapment

NASA Technical Reports Server (NTRS)

Bolshinskiy, L.G.; Hastings, L.J.; Stathman, G.

2007-01-01

Cryogenic liquid acquisition devices (LADs) for space-based propulsion interface directly with the feed system, which can be a significant heat leak source. Further, the accumulation of thermal energy within LAD channels can lead to the loss of sub-cooled propellant conditions and result in feed system cavitation during propellant outflow. Therefore, the fundamental question addressed by this program was: "To what degree is natural convection in a cryogenic liquid constrained by the capillary screen meshes envisioned for LADs.?"Testing was first conducted with water as the test fluid, followed by LN2 tests. In either case, the basic experimental approach was to heat the bottom of a cylindrical column of test fluid to establish stratification patterns measured by temperature sensors located above and below a horizontal screen barrier position. Experimentation was performed without barriers, with screens, and with a solid barrier. The two screen meshes tested were those typically used by LAD designers, "200x1400" and "325x2300", both with Twill Dutch Weave. Upon consideration of both the water and LN2 data it was concluded that heat transfer across the screen meshes was dependent upon barrier thermal conductivity and that the capillary screen meshes were impervious to natural convection currents.

Discovery of Dihydrobenzoxazepinone (GS-6615) Late Sodium Current Inhibitor (Late INai), a Phase II Agent with Demonstrated Preclinical Anti-Ischemic and Antiarrhythmic Properties.

PubMed

Zablocki, Jeff A; Elzein, Elfatih; Li, Xiaofen; Koltun, Dmitry O; Parkhill, Eric Q; Kobayashi, Tetsuya; Martinez, Ruben; Corkey, Britton; Jiang, Haibo; Perry, Thao; Kalla, Rao; Notte, Gregory T; Saunders, Oliver; Graupe, Michael; Lu, Yafan; Venkataramani, Chandru; Guerrero, Juan; Perry, Jason; Osier, Mark; Strickley, Robert; Liu, Gongxin; Wang, Wei-Qun; Hu, Lufei; Li, Xiao-Jun; El-Bizri, Nesrine; Hirakawa, Ryoko; Kahlig, Kris; Xie, Cheng; Li, Cindy Hong; Dhalla, Arvinder K; Rajamani, Sridharan; Mollova, Nevena; Soohoo, Daniel; Lepist, Eve-Irene; Murray, Bernard; Rhodes, Gerry; Belardinelli, Luiz; Desai, Manoj C

2016-10-03

Late sodium current (late I Na ) is enhanced during ischemia by reactive oxygen species (ROS) modifying the Na v 1.5 channel, resulting in incomplete inactivation. Compound 4 (GS-6615, eleclazine) a novel, potent, and selective inhibitor of late I Na , is currently in clinical development for treatment of long QT-3 syndrome (LQT-3), hypertrophic cardiomyopathy (HCM), and ventricular tachycardia-ventricular fibrillation (VT-VF). We will describe structure-activity relationship (SAR) leading to the discovery of 4 that is vastly improved from the first generation late I Na inhibitor 1 (ranolazine). Compound 4 was 42 times more potent than 1 in reducing ischemic burden in vivo (S-T segment elevation, 15 min left anteriorior descending, LAD, occlusion in rabbits) with EC 50 values of 190 and 8000 nM, respectively. Compound 4 represents a new class of potent late I Na inhibitors that will be useful in delineating the role of inhibitors of this current in the treatment of patients.

Epicardial fat thickness correlates with P-wave duration, left atrial size and decreased left ventricular systolic function in morbid obesity.

PubMed

Fernandes-Cardoso, A; Santos-Furtado, M; Grindler, J; Ferreira, L A; Andrade, J L; Santo, M A

2017-08-01

Epicardial fat (EF) is increased in obesity and has important interactions with atrial and ventricular myocardium. Most of the evidence in this scenario can be confused by the presence of comorbidities such as hypertension, diabetes and dyslipidemia, which are very common in this population. The influence of EF on atrial remodeling and cardiac function demands further investigation on morbidly obese without these comorbidities. We prospectively recruited 20 metabolically healthy morbidly obese and 20 normo-weights controls. The maximum P-wave duration (PWD) was analyzed by 12-lead electrocardiogram. Left atrial diameter (LAD), left ventricular ejection fraction (LVEF) and EF thickness (EFT) were evaluated by two-dimensional echocardiography. The mean of maximum PWD and LAD were significantly larger in the obese group as compared to the control group: 109.55 ± 11.52 ms × 89.38 ± 11.19 ms and 36.12 ± 3.46 mm × 31.45 ± 2.64 mm, (p < 0.0001). The mean LVEF was lower in the obese group: 63.15 ± 4.25% × 66.17 ± 3.37% (p < 0.017). The mean EFT was higher in the obese group: 7.72 ± 1.60 mm × 3.10 ± 0.85 mm (p < 0.0001). A positive correlation was found between EFT and PWD (r = 0.70; p = 0.001) and LAD (r = 0.667; p = 0.001). An inverse correlation was found between EFT and LVEF (r = -0.523; p = 0.001). In a multiple multivariate regression analysis the EFT remains correlated with LAD and LVEF. In a select group of morbidly obese, the excess of EF had a significant impact on atrial remodeling and cardiac function. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Louisiana SIP: LAC 33:III Ch 2147. Limiting Volatile Organic Compound (VOC) Emissions from Reactor Processes and Distillation Operations in Synthetic Organic Chemical manufacturing Industry (SOCMI); SIP effective 2011-08-04 (LAd34) to 2017-09-27

EPA Pesticide Factsheets

Louisiana SIP: LAC 33:III Ch 2147. Limiting Volatile Organic Compound (VOC) Emissions from Reactor Processes and Distillation Operations in Synthetic Organic Chemical manufacturing Industry (SOCMI); SIP effective 2011-08-04 (LAd34) to 2017-09-27

Reduced expression of mitochondrial electron transport chain proteins from hibernating hearts relative to ischemic preconditioned hearts in the second window of protection.

PubMed

Cabrera, Jesús A; Butterick, Tammy A; Long, Eric K; Ziemba, Elizabeth A; Anderson, Lorraine B; Duffy, Cayla M; Sluiter, Willem; Duncker, Dirk J; Zhang, Jianyi; Chen, Yingjie; Ward, Herbert B; Kelly, Rosemary F; McFalls, Edward O

2013-07-01

Although protection against necrosis has been observed in both hibernating (HIB) and ischemic preconditioned hearts in the second window of protection (SWOP), a comparison of the mitochondrial proteome between the two entities has not been previously performed. Anesthetized swine underwent instrumentation with a fixed constrictor around the LAD artery and were followed for 12 weeks (HIB; N=7). A second group of anesthetized swine underwent ischemic preconditioning by inflating a balloon within the LAD artery 10 times for 2 min, each separated by 2 min reperfusion and were sacrificed 24h later (SWOP; N=7). Myocardial blood flow and high-energy nucleotides were obtained in the LAD region and normalized to remote regions. Post-sacrifice, protein content as measured with iTRAQ was compared in isolated mitochondria from the LAD area of a Sham heart. Basal regional blood flow in the LAD region when normalized to the remote region was 0.86±0.04 in HIB and 1.02±0.02 in SWOP tissue (P<0.05). Despite reduced regional blood flows in HIB hearts, ATP content in the LAD region, when normalized to the remote region was similar in HIB versus SWOP (1.06±0.06 and 1.02±0.05 respectively; NS) as was the transmural phosphocreatine (PCr) to ATP ratio (2.1±0.2 and 2.2±0.2 respectively; NS). Using iTRAQ, 64 common proteins were identified in HIB and SWOP hearts. Compared with SWOP, the relative abundance of mitochondrial proteins involved with electron transport chain (ETC) were reduced in HIB including NADH dehydrogenase, Cytochrome c reductase and oxidase, ATP synthase, and nicotinamide nucleotide transhydrogenase. Within chronically HIB heart tissue with reduced blood flow, the relative abundance of mitochondrial ETC proteins is decreased when compared with SWOP tissue. These data support the concept that HIB heart tissue subjected to chronically reduced blood flow is associated with a down-regulation in the expression of key mitochondrial proteins involved in electron transport. Published by Elsevier Ltd.

Various clinical scenarios leading to development of the string sign of the internal thoracic artery after coronary bypass surgery: the role of competitive flow, a case series.

PubMed

Kolozsvari, Rudolf; Galajda, Zoltan; Ungvari, Tamas; Szabo, Gabor; Racz, Ildikó; Szerafin, Tamás; Herzfeld, István; Edes, István; Peterffy, Arpad; Koszegi, Zsolt

2012-01-30

The left internal mammary artery (LIMA) is the choice for grafting of the left anterior descending coronary artery (LAD). One possible mechanism of the rare graft failure involve the presence of competitive flow. 105 patients who had undergone coronary bypass grafting between 1998 and 2000 were included in this observational study. The recatheterizations were performed 28 months after the operations. The rate of patency the LIMA grafts was determined, and the cases with graft failure were analyzed. The LIMA graft was patent in 99 patients (94%). Six patients (6%) exhibited diffuse involution of the graft (string sign). The string sign was always associated with competitive flow as the basis of the LIMA graft involution. In one case quantitative re-evaluation of the preoperative coronary angiography revealed merely less than 50% diameter stenosis on the LAD with a nonligated side-branch of the LIMA. At recatheterization in two patients the pressure wire measurements demonstrated only a non-significant decrease of the fractional flow reserve (0.83 and 0.89), despite the 53% and 57% diameter stenosis in the angiogram. Another patient displayeda significant regression of the LAD lesion between the pre- and postoperative coronary angiography (from 76% to 44%) as the cause of the development of the competitive flow. In one instance, a radial artery graft on the LAD during a redo bypass operation resulted in competitive flow in the radial graft due to the greater diameter than that of the LIMA. In a further patient, competitive flow developed from a short sequential part of the LIMA graft between the nonsignificantly stenosed diagonal branch and the LAD, with involution of the main part of the graft to the diagonal branch. The most common cause of the development of the string sign of a LIMA graft due to competitive flow is overassessment of the lesion of the LAD. Regression of a previous lesion or some other neighboring graft can also cause the phenomenon.

Breast cancer prognosis by combinatorial analysis of gene expression data.

PubMed

Alexe, Gabriela; Alexe, Sorin; Axelrod, David E; Bonates, Tibérius O; Lozina, Irina I; Reiss, Michael; Hammer, Peter L

2006-01-01

The potential of applying data analysis tools to microarray data for diagnosis and prognosis is illustrated on the recent breast cancer dataset of van 't Veer and coworkers. We re-examine that dataset using the novel technique of logical analysis of data (LAD), with the double objective of discovering patterns characteristic for cases with good or poor outcome, using them for accurate and justifiable predictions; and deriving novel information about the role of genes, the existence of special classes of cases, and other factors. Data were analyzed using the combinatorics and optimization-based method of LAD, recently shown to provide highly accurate diagnostic and prognostic systems in cardiology, cancer proteomics, hematology, pulmonology, and other disciplines. LAD identified a subset of 17 of the 25,000 genes, capable of fully distinguishing between patients with poor, respectively good prognoses. An extensive list of 'patterns' or 'combinatorial biomarkers' (that is, combinations of genes and limitations on their expression levels) was generated, and 40 patterns were used to create a prognostic system, shown to have 100% and 92.9% weighted accuracy on the training and test sets, respectively. The prognostic system uses fewer genes than other methods, and has similar or better accuracy than those reported in other studies. Out of the 17 genes identified by LAD, three (respectively, five) were shown to play a significant role in determining poor (respectively, good) prognosis. Two new classes of patients (described by similar sets of covering patterns, gene expression ranges, and clinical features) were discovered. As a by-product of the study, it is shown that the training and the test sets of van 't Veer have differing characteristics. The study shows that LAD provides an accurate and fully explanatory prognostic system for breast cancer using genomic data (that is, a system that, in addition to predicting good or poor prognosis, provides an individualized explanation of the reasons for that prognosis for each patient). Moreover, the LAD model provides valuable insights into the roles of individual and combinatorial biomarkers, allows the discovery of new classes of patients, and generates a vast library of biomedical research hypotheses.

Frequency, origins and courses of anomalous coronary arteries in 607 Turkish children with tetralogy of Fallot.

PubMed

Kervancioglu, Mehmet; Tokel, Kursad; Varan, Birgul; Yildirim, Selman Vefa

2011-01-01

The aim of this study was to investigate the incidence, origins and courses of coronary artery anomalies using a combination of angiographic and surgical methods in Turkish children with tetralogy of Fallot (ToF). Seventy-seven patients in whom coronary artery anomalies had been identified by angiography and/or at operation out of 549 ToF and 58 Fallot-type double outlet right ventricle (total 607) patients, were enrolled in the study. Coronary artery anomalies were identified in 12.7% of the patients. The incidence was 12.2% (67/549) in patients with aortic overriding 50%, and 17.2% (10/58) with aortic overriding 〉 50% (p 〉 0.05). The incidence of anomalous coronary arteries crossing the right ventricular outflow tract (RVOT) was 7.91%. The commonest anomaly was the left anterior descending artery (LAD) or accessory LAD arising from the right coronary artery (RCA; n = 25). Other frequent anomalies were single coronary ostium (n = 21) and enlarged conal branch of RCA (n = 18). In 62.3% (48/77) of the patients with a coronary anomaly, the anomalous vessels were crossing the RVOT. The ratio of crossing the RVOT was 92.0% for LAD arising from the RCA, 66.7% for conal branch, and 42.9% for single coronary ostium. Two thirds of the anomalous coronary arteries were crossing the RVOT, and had surgical importance. The most frequent coronary artery anomaly that crossed the RVOT was the LAD or the accessory LAD arising from the RCA. Also, an enlarged conus artery should be considered as an anomaly because of its surgical importance, given its high rate of crossing the RVOT.

Doppler echocardiographic myocardial stunning index predicts recovery of left ventricular systolic function after primary percutaneous coronary intervention.

PubMed

Sharif, Dawod; Matanis, Wisam; Sharif-Rasslan, Amal; Rosenschein, Uri

2016-10-01

Myocardial stunning is responsible for partially reversible left ventricular (LV) systolic dysfunction after successful primary percutaneous coronary intervention (PPCI) in patients with acute ST-elevation myocardial infarction (STEMI). To test the hypothesis that early coronary blood flow (CBF) to LV systolic function ratios, as an equivalent to LV stunning index (SI), predict recovery of LV systolic function after PPCI in patients with acute STEMI. Twenty-four patients with acute anterior STEMI who had successful PPCI were evaluated and compared to 96 control subjects. Transthoracic echocardiography with measurement of LV ejection fraction (EF), LV, and left anterior descending (LAD) coronary artery area wall-motion score index (WMSI) as well as Doppler sampling of LAD blood velocities, early after PPCI and 5 days later, were performed. SI was evaluated as the early ratio of CBF parameters in the LAD to LV systolic function parameters. Early SI-LVEF well predicted late LVEF (r=.51, P<.01) and the change in LVEF (r=.48, P<.017). Early SI-LVMSI predicted well late LVEF (r=.56, P<.006) and the change in LVEF (r=.46, P<.028). Early SI-LADWMSI predicted late LVEF (r=.44, P<.028). Other SI indices measured as other LAD-CBF to LV systolic function parameters were not predictive of late LV systolic function. LV stunning indices measured as early LAD flow to LVEF, LVWMSI, and LADWMSI ratios well predicted late LVEF and the change in LVEF. Thus, greater early coronary artery flow to LV systolic function parameter ratios predict a better improvement in late LV systolic function after PPCI. © 2016, Wiley Periodicals, Inc.

Complete cardiac regeneration in a mouse model of myocardial infarction.

PubMed

Haubner, Bernhard Johannes; Adamowicz-Brice, Martyna; Khadayate, Sanjay; Tiefenthaler, Viktoria; Metzler, Bernhard; Aitman, Tim; Penninger, Josef M

2012-12-01

Cardiac remodeling and subsequent heart failure remain critical issues after myocardial infarction despite improved treatment and reperfusion strategies. Recently, complete cardiac regeneration has been demonstrated in fish and newborn mice following resection of the cardiac apex. However, it remained entirely unclear whether the mammalian heart can also completely regenerate following a complex cardiac ischemic injury. We established a protocol to induce a severe heart attack in one-day-old mice using left anterior descending artery (LAD) ligation. LAD ligation triggered substantial cardiac injury in the left ventricle defined by Caspase 3 activation and massive cell death. Ischemia-induced cardiomyocyte death was also visible on day 4 after LAD ligation. Remarkably, 7 days after the initial ischemic insult, we observed complete cardiac regeneration without any signs of tissue damage or scarring. This tissue regeneration translated into long-term normal heart functions as assessed by echocardiography. In contrast, LAD ligations in 7-day-old mice resulted in extensive scarring comparable to adult mice, indicating that the regenerative capacity for complete cardiac healing after heart attacks can be traced to the first week after birth. RNAseq analyses of hearts on day 1, day 3, and day 10 and comparing LAD-ligated and sham-operated mice surprisingly revealed a transcriptional programme of major changes in genes mediating mitosis and cell division between days 1, 3 and 10 postnatally and a very limited set of genes, including genes regulating cell cycle and extracellular matrix synthesis, being differentially regulated in the regenerating hearts. We present for the first time a mammalian model of complete cardiac regeneration following a severe ischemic cardiac injury. This novel model system provides the unique opportunity to uncover molecular and cellular pathways that can induce cardiac regeneration after ischemic injury, findings that one day could be translated to human heart attack patients.

Effects of coil closure of patent ductus arteriosus on left anterior descending coronary artery blood flow using transthoracic Doppler echocardiography.

PubMed

Harada, Kenji; Toyono, Manotomo; Tamura, Masamichi

2004-06-01

Transthoracic Doppler echocardiography provides noninvasive measurements of coronary blood flow in the left anterior descending coronary artery (LAD). This method has the potential to show the effects of acute changes in loading conditions on blood flow. Coil closure of patent ductus arteriosus (PDA) is a model of acute changes in blood pressure and left ventricular (LV) preload that influences coronary blood flow. We applied this technique to assess the coronary blood flow changes for patients with PDA before and immediately after PDA coil closure. We examined 9 patients (1.8 +/- 1.1 years) with simple PDA and 8 age-matched healthy children. LV dimensions and LV mass were measured. Maximum peak flow velocity and flow volume in the LAD were measured. Pulmonary to systemic flow ratios (Qp/Qs) were obtained by cardiac catheterization. After PDA coil closure, LV end-diastolic dimension decreased, and systolic and diastolic blood pressures increased significantly. The maximum peak flow velocity, LAD flow volume, and the ratio of LAD flow volume to LV mass increased significantly. The changes in maximum peak flow velocity and the ratio of LAD flow volume to LV mass (F/M) correlated positively with the changes in diastolic pressure and Qp/Qs. In 5 patients who had Qp/Qs > 1.5, the mean F/M was significantly lower compared with control subjects, but they increased to normal values after coil closure of PDA. PDA coil closure increases diastolic pressure and decreases Qp/Qs, resulting in improvement of myocardial perfusion. These findings provide new insights into the relationship between cardiac function and coronary circulation in pediatric patients with heart diseases associated with PDA.

Transthoracic Coronary Flow Data at Rest Predict High-Risk Stress Tests.

PubMed

Zagatina, Angela; Zhuravskaya, Nadezhda; Vareldzhyan, Yuliya; Kamenskikh, Maxim; Shmatov, Dmitry; Benacka, Jozef; Kucera, Martin; Kruzliak, Peter

2018-06-01

Background Several recent studies have reported the opportunity to diagnose significant narrowing of the coronary arteries without stress testing using local flow acceleration. Purpose To define how often patients with increased coronary flow velocities at rest (≥ 0.70 m/s) have a positive exercise echocardiography test. Material and Methods A total of 150 patients scheduled for exercise echocardiography were studied using transthoracic Doppler echocardiography in order to assess coronary artery flow velocity before exercise. Pulsed wave Doppler registered blood flow velocity placed on the color signal. The maximal diastolic velocity of coronary flow was measured. Results Of participants, 16% had a velocity of more than 0.70 m/s in the left main/proximal left anterior/proximal left circumflex arteries (LM/pLAD). A significant correlation was observed between the value of the maximal velocity in LM/pLAD and the ejection fraction at the peak of exercise ( r ≈ -0.39, P < 0.0001); between the value of the maximal velocity in LM/pLAD and index of wall motion abnormalities (IWMA) at the peak of exercise ( r ≈ 0.44, P < 0.0001); and between the value of the maximal velocity in LM/pLAD and dIWMA ( r ≈ 0.41, P < 0.0001). Afterwards, severe ischemia in stress echocardiography tests was observed in this group. The average IWMA of these tests was found to be 2.3. Sixty-two angiograms were available for comparison with Doppler data. Conclusion There is a significant correlation between the value of the maximal velocity in LM/pLAD/pLCx at rest and the severity of wall motion abnormalities during exercise tests.

Edge-to-Edge Technique to Minimize Ovelapping of Multiple Bioresorbable Scaffolds Plus Drug Eluting Stents in Revascularization of Long Diffuse Left Anterior Descending Coronary Artery Disease.

PubMed

Rigatelli, Gianluca; Avvocata, Fabio Dell'; Ronco, Federico; Giordan, Massimo; Roncon, Loris; Caprioglio, Francesco; Grassi, Giuseppe; Faggian, Giuseppe; Cardaioli, Paolo

2016-06-01

Implantation of Drug Eluting Stents (DES) plus bioresorbable scaffolds (BVS) in very long diffuse left anterior descending coronary artery (LAD) disease may be problematic because of multiple devices overlapping. We sought to assess the short and mid-tern outcomes of combined implantation of DES and BVS using a novel "edge-to-edge" technique in patients with diffuse LAD disease. Patients with long diffuse LAD disease were enrolled in a prospective registry from 1st August 2014 to 1st August 2015 and treated with IVUS-aided percutaneous coronary intervention using a DES plus a single or multiple BVS using a novel "edge-to-edge" technique. Clinical follow up and invasive follow up driven by clinical justification was performed. Twenty-three patients (5 females, mean age 59.1± 9.1 years) were enrolled. Mean length of LAD disease was 73.1 ± 20.6 mm. Mean number of DES and BVS implanted was 1.2 ± 0.4 and 1.7 ± 1.3, respectively. At a mean follow-up of 11.3 ± 3.8 months, no stent thrombosis or MACE were observed. Angiographic and IVUS follow-up at a mean of 6.6 ± 0.7 months showed no significant angiographic restenosis and no appreciable stent gaps. In revascularization of long diffuse disease of the LAD, the edge-to-edge implantation technique appears to be feasible resulting in no restenosis or thrombosis on the short-term follow-up. (J Interven Cardiol 2016;29:275-284). © 2016, Wiley Periodicals, Inc.

Effect of sildenafil citrate (Viagra) on coronary flow in normal subjects.

PubMed

Ishikura, Fuminobu; Beppu, Shintaro; Ueda, Hiroaki; Nehra, Ajay; Khandheria, Bijoy K

2008-01-01

The purpose of this study was to evaluate the effect of sildenafil citrate (Viagra) on coronary function in normal subjects. The study assessed mean blood pressure, left anterior descending coronary artery (LAD) flow, and echocardiographic variables before and 30 and 60 minutes after taking 50 mg of sildenafil citrate. The mean velocity of LAD flow was assessed with Doppler flow imaging. The study subjects were 6 healthy male volunteers (mean age 37 years). The mean velocity of LAD flow increased 60 minutes after taking sildenafil citrate, but there were no other changes. Two volunteers felt mild flashing and one had mild headache during the study. Sildenafil citrate caused vasodilatation in a normal coronary artery without systemic pressure drops. These results suggest that the agent itself did not have negative effects on the heart in normal subjects.

Louisiana SIP: LAC 33:III Ch. 7 Section 701. Purpose and Information Regarding Standards for PM10, SO2, CO, Atmospheric Oxidants, NOx and Pb; SIP effective 1989-05-08 (LAc49) to 2011-08-03 (LAd34 - Revised)

EPA Pesticide Factsheets

Louisiana SIP: LAC 33:III Ch. 7 Section 701. Purpose and Information Regarding Standards for PM10, SO2, CO, Atmospheric Oxidants, NOx and Pb; SIP effective 1989-05-08 (LAc49) to 2011-08-03 (LAd34 - Revised)

Light assisted drying (LAD) for protein stabilization: optical characterization of samples

NASA Astrophysics Data System (ADS)

Young, Madison A.; McKinnon, Madison E.; Elliott, Gloria D.; Trammell, Susan R.

2018-02-01

Light-Assisted Drying (LAD) is a novel biopreservation technique which allows proteins to be immobilized in a dry, amorphous solid at room temperature. Indicator proteins are used in a variety of diagnostic assays ranging from highthroughput 96-well plates to new microfluidic devices. A challenge in the development of protein-based assays is preserving the structure of the protein during production and storage of the assay, as the structure of the protein is responsible for its functional activity. Freeze-drying or freezing are currently the standard for the preservation of proteins, but these methods are expensive and can be challenging in some environments due to a lack of available infrastructure. An inexpensive, simple processing method that enables supra-zero temperature storage of proteins used in assays is needed. Light-assisted drying offers a relatively inexpensive method for drying samples. Proteins suspended in a trehalose solution are dehydrated using near-infrared laser light. The laser radiation speeds drying and as water is removed the sugar forms a protective matrix. The goal of this study is optically characterize samples processed with LAD. We use polarized light imaging (PLI) to look at crystallization kinetics of samples and determine optimal humidity. PLI shows a 62.5% chance of crystallization during LAD processing and negligible crystallization during low RH storage.

A novel point mutation in CD18 causing the expression of dysfunctional CD11/CD18 leucocyte integrins in a patient with leucocyte adhesion deficiency (LAD)

PubMed Central

Mathew, E C; Shaw, J M; Bonilla, F A; Law, S K A; Wright, D A

2000-01-01

Leucocyte adhesion deficiency type 1 (LAD-1) is characterized by the incapacity of leucocytes to carry out their adhesion functions via their CD11/CD18 antigens, which are also referred to as the leucocyte integrins. The patients generally suffer from poor wound healing and recurrent bacterial and fungal infections. In severe cases, the infections are often systemic and life-threatening. A LAD patient (AW) of moderate phenotype has been identified but, unlike most other cases, the level of CD11/CD18 antigens on her leucocytes are uncharacteristically high for a LAD patient. Molecular analysis revealed that she is a compound heterozygote for CD18 mutations. She has inherited a D231H mutation from her father and a G284S mutation from her mother. By transfection studies, it was established that the G284S mutation does not support CD11/CD18 antigen expression on the cell surface. In contrast, the D231H mutation does not affect CD18 forming integrin heterodimers with the CD11 antigens on the cell surface. However, the expressed integrins with the D231H mutation are not adhesive to ligands. PMID:10886250

Bovine Intestinal Alkaline Phosphatase Reduces Inflammation After Induction of Acute Myocardial Infarction in Mice.

PubMed

Fiechter, Danielle; Kats, Suzanne; Brands, Ruud; van Middelaar, Ben; Pasterkamp, Gerard; de Kleijn, Dominique; Seinen, Willem

2011-10-01

There has been increasing evidence suggesting that lipopolysaccharide or endotoxin may be an important activator of the innate immune system after acute myocardial infarction. Bovine intestinal alkaline phosphatase reduces inflammation in several endotoxin mediated diseases by dephosphorylation of the lipid A moiety of lipopolysaccharide. The aim of this study was to investigate the effect of bovine intestinal alkaline phosphatase on reducing inflammation after acute myocardial infarction. Just before permanent ligation of the left anterior descending coronary (LAD) artery to induce acute myocardial infarction in Balb/c mice, bovine intestinal alkaline phosphatase (bIAP) was administrated intravenously. After 4 hours, mice were sacrificed and the inflammatory response was assessed. Acute myocardial infarction induced the production of different cytokines, which were measured in blood. Treatment with bovine intestinal alkaline phosphatase resulted in a significant reduction of the pro-inflammatory cytokines IL-6, IL-1β and the chymase mouse mast cell protease-1. No difference in the production of the anti-inflammatory cytokine IL-10 was observed between the control group and the bovine intestinal alkaline phosphatase treated group. In a mouse model of permanent LAD coronary artery ligation, bIAP diminishes the pro-inflammatory responses but does not have an effect on the anti-inflammatory response in the acute phase after acute myocardial infarction.

Validation of Left Atrial Volume Estimation by Left Atrial Diameter from the Parasternal Long-Axis View.

PubMed

Canciello, Grazia; de Simone, Giovanni; Izzo, Raffaele; Giamundo, Alessandra; Pacelli, Filomena; Mancusi, Costantino; Galderisi, Maurizio; Trimarco, Bruno; Losi, Maria-Angela

2017-03-01

Measurement of left atrial (LA) volume (LAV) is recommended for quantification of LA size. Only LA anteroposterior diameter (LAd) is available in a number of large cohorts, trials, or registries. The aim of this study was to evaluate whether LAV may be reasonably estimated from LAd. One hundred forty consecutive patients referred to our outpatient clinics were prospectively enrolled to measure LAd from the long-axis view on two-dimensional echocardiography. LA orthogonal dimensions were also taken from apical four- and two-chamber views. LAV was measured using the Simpson, area-length, and ellipsoid (LAV e ) methods. The first 70 patients were the learning series and the last 70 the testing series (TeS). In the learning series, best-fitting regression analysis of LAV-LAd was run using all LAV methods, and the highest values of F were chosen among the regression equations. In the TeS, the best-fitting regressions were used to estimate LAV from LAd. In the learning series, the best-fitting regression was linear for the Spearman method (r 2  = 0.62, F = 111.85, P = .0001) and area-length method (r 2  = 0.62, F = 112.24, P = .0001) and powered for the LAV e method (r 2  = 0.81, F = 288.41, P = .0001). In the TeS, the r 2 value for LAV prediction was substantially better using the LAV e method (r 2  = 0.89) than the Simpson (r 2  = 0.72) or area-length (r 2  = 0.70) method, as was the intraclass correlation (ρ = 0.96 vs ρ = 0.89 and ρ = 0.89, respectively). In the TeS, the sensitivity and specificity of LA dilatation by the estimated LAV e method were 87% and 90%, respectively. LAV can be estimated from LAd using a nonlinear equation with an elliptical model. The proposed method may be used in retrospective analysis of existing data sets in which determination of LAV was not programmed. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Voxel-Based 3-D Tree Modeling from Lidar Images for Extracting Tree Structual Information

NASA Astrophysics Data System (ADS)

Hosoi, F.

2014-12-01

Recently, lidar (light detection and ranging) has been used to extracting tree structural information. Portable scanning lidar systems can capture the complex shape of individual trees as a 3-D point-cloud image. 3-D tree models reproduced from the lidar-derived 3-D image can be used to estimate tree structural parameters. We have proposed the voxel-based 3-D modeling for extracting tree structural parameters. One of the tree parameters derived from the voxel modeling is leaf area density (LAD). We refer to the method as the voxel-based canopy profiling (VCP) method. In this method, several measurement points surrounding the canopy and optimally inclined laser beams are adopted for full laser beam illumination of whole canopy up to the internal. From obtained lidar image, the 3-D information is reproduced as the voxel attributes in the 3-D voxel array. Based on the voxel attributes, contact frequency of laser beams on leaves is computed and LAD in each horizontal layer is obtained. This method offered accurate LAD estimation for individual trees and woody canopy trees. For more accurate LAD estimation, the voxel model was constructed by combining airborne and portable ground-based lidar data. The profiles obtained by the two types of lidar complemented each other, thus eliminating blind regions and yielding more accurate LAD profiles than could be obtained by using each type of lidar alone. Based on the estimation results, we proposed an index named laser beam coverage index, Ω, which relates to the lidar's laser beam settings and a laser beam attenuation factor. It was shown that this index can be used for adjusting measurement set-up of lidar systems and also used for explaining the LAD estimation error using different types of lidar systems. Moreover, we proposed a method to estimate woody material volume as another application of the voxel tree modeling. In this method, voxel solid model of a target tree was produced from the lidar image, which is composed of consecutive voxels that filled the outer surface and the interior of the stem and large branches. From the model, the woody material volume of any part of the target tree can be directly calculated easily by counting the number of corresponding voxels and multiplying the result by the per-voxel volume.

Sci—Thur AM: YIS - 01: Dosimetric Analysis of Respiratory Induced Cardiac Intrafraction Motion in Left-sided Breast Cancer Radiotherapy

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

El-Sherif, O; Xhaferllari, I; Patrick, J

2014-08-15

Introduction: Long-term cardiac side effects in left-sided breast cancer patients (BREL) after post-operative radiotherapy has become one of the most debated issues in radiation oncology. Through breathing-adapted radiotherapy the volume of the heart exposed to radiation can be significantly reduced by delivering the radiation only at the end of inspiration phase of the respiratory cycle, this is referred to as inspiration gating (IG). The purpose of this study is to quantify the potential reduction in cardiac exposure during IG compared to conventional BREL radiotherapy and to assess the dosimetric impact of cardiac motion due to natural breathing. Methods: 24 BRELmore » patients treated with tangential parallel opposed photon beams were included in this study. All patients received a standard fast helical planning CT (FH-CT) and a 4D-CT. Treatment plans were created on the FH-CT using a clinical treatment planning system. The original treatment plan was then superimposed onto the end of inspiration CT and all 10 phases of the 4D-CT to quantify the dosimetric impact of respiratory motion and IG through 4D dose accumulation. Results: Through IG the mean dose to the heart, left ventricle, and left anterior descending artery (LAD) can be reduced in comparison to the clinical standard BREL treatment by as much as 8.39%, 10.11%, and 13.71% respectively (p < 0.05). Conclusion: Failure to account for respiratory motion can lead to under or overestimation in the calculated DVH for the heart, and it's sub-structures. IG can reduce cardiac exposure especially to the LAD during BREL radiotherapy.« less

In vivo characterization of acute myocardial ischemia using photoacoustic imaging with a focused transducer

NASA Astrophysics Data System (ADS)

Li, Zhifang; Chen, Haiyu; Xie, Wengming; Li, Hui

2011-03-01

We explore the feasibility of using photoacoustic imaging based on a focused transducer to characterizing acute myocardial ischemia at different stage. In this study, we blocked rat left anterior coronary descending artery (LAD) to induce the acute myocardial ischemia. The results show that the intensity and areas of photoacoustic images of myocardial decrease with the LAD time increasing, which suggests that photoacoustic imaging has a potential for diagnosis of acute myocardial ischemia.

Inverted Outflow Ground Testing of Cryogenic Propellant Liquid Acquisition Devices

NASA Technical Reports Server (NTRS)

Chato, David J.; Hartwig, Jason W.; Rame, Enrique; McQuillen, John B.

2014-01-01

NASA is currently developing propulsion system concepts for human exploration. These propulsion concepts will require the vapor free acquisition and delivery of the cryogenic propellants stored in the propulsion tanks during periods of microgravity to the exploration vehicles engines. Propellant management devices (PMDs), such as screen channel capillary liquid acquisition devices (LADs), vanes and sponges have been used for earth storable propellants in the Space Shuttle Orbiter and other spacecraft propulsion systems, but only very limited propellant management capability currently exists for cryogenic propellants. NASA is developing PMD technology as a part of their cryogenic fluid management (CFM) project. System concept studies have looked at the key factors that dictate the size and shape of PMD devices and established screen channel LADs as an important component of PMD design. Modeling validated by normal gravity experiments is examining the behavior of the flow in the LAD channel assemblies (as opposed to only prior testing of screen samples) at the flow rates representative of actual engine service (similar in size to current launch vehicle upper stage engines). Recently testing of rectangular LAD channels has included inverted outflow in liquid oxygen and liquid hydrogen. This paper will report the results of liquid oxygen testing compare and contrast them with the recently published hydrogen results; and identify the sensitivity these results to flow rate and tank internal pressure.

Transthoracic ultrasonic tissue indices identify patients with severe left anterior descending artery stenosis. Correlation with fractional flow reserve. Pilot study.

PubMed

Dobrowolski, Piotr; Kowalski, Mirosław; Rybicka, Justyna; Lech, Agnieszka; Tyczyński, Paweł; Witkowski, Adam; Hoffman, Piotr

2016-01-01

The aim of this study was to evaluate the potential clinical application of ultrasonic tissue indices, with a focus on systolic strain (SS) and systolic strain rate (SSR) parameters derived from transthoracic echocardiography, in the assessment of left anterior descending artery (LAD) stenosis. The data of 30 patients with significant LAD stenosis were analysed. All patients underwent transthoracic echocardiography to obtain systolic myocardial velocity (Sm), longitudinal SS, and SSR from basal, mid, and apical segments of anterior and inferior walls in two-chamber apical view. Severity of LAD obstruction was measured by means of fractional flow reserve (FFR) during coronary catheterisation. Systolic velocities, strain, and strain rate measured in basal, middle, and apical segments of the anterior left ventricular (LV) wall were lower when compared to those obtained from the corresponding, i.e. unaffected, inferior LV wall. There was a significant correlation between FFR and the value of SS, SSR characterising the apical LV segment of the anterior wall (r = -0.583, p = 0.01; r = -0.598, p = 0.01, respectively). Moreover, we found significant correlation between FFR and Sm in the mid-segment of the LV anterior wall (r = 0.611, p = 0.009). We conclude that SS and SSR obtained from the apical segment of the anterior LV wall may be related to the severity of LAD stenosis.

Inverted Outflow Ground Testing of Cryogenic Propellant Liquid Acquisition Devices

NASA Technical Reports Server (NTRS)

Chato, David J.; Hartwig, Jason W.; Rame, Enrique; McQuillen, John B.

2014-01-01

NASA is currently developing propulsion system concepts for human exploration. These propulsion concepts will require the vapor free acquisition and delivery of the cryogenic propellants stored in the propulsion tanks during periods of microgravity to the exploration vehicles engines. Propellant management devices (PMD's), such as screen channel capillary liquid acquisition devices (LAD's), vanes and sponges have been used for earth storable propellants in the Space Shuttle Orbiter and other spacecraft propulsion systems, but only very limited propellant management capability currently exists for cryogenic propellants. NASA is developing PMD technology as a part of their cryogenic fluid management (CFM) project. System concept studies have looked at the key factors that dictate the size and shape of PMD devices and established screen channel LADs as an important component of PMD design. Modeling validated by normal gravity experiments is examining the behavior of the flow in the LAD channel assemblies (as opposed to only prior testing of screen samples) at the flow rates representative of actual engine service (similar in size to current launch vehicle upper stage engines). Recently testing of rectangular LAD channels has included inverted outflow in liquid oxygen and liquid hydrogen. This paper will report the results of liquid oxygen testing compare and contrast them with the recently published hydrogen results; and identify the sensitivity of these results to flow rate and tank internal pressure.

The WFM Instrument of the LOFT mission

NASA Astrophysics Data System (ADS)

Gálvez, J. L.; Hernanz, M.; Álvarez, L.; LOFT/WFM Team

2013-05-01

LOFT, the Large Observatory For X-ray Timing, was selected by ESA in 2011 as one of the four M3 (medium class) missions concepts of the Cosmic Vision programme that will compete for a launch opportunity at the start of the 2020s. LOFT includes two instruments: the Large Area Detector (LAD), a ˜10 m^2 collimated X-ray detector in the 2-50 keV range (up to 80 keV in extended mode), and the Wide Field Monitor (WFM), a coded-mask wide field X-ray monitor based on silicon radiation detectors. We, the Institute of Space Sciences (CSIC-IEEC) in Barcelona, are deeply involved in the LOFT mission, sharing the leadership of the WFM instrument with DTU Space in Denmark. We are responsible of the mechanics of the WFM, including the structural and thermal design. The WFM baseline is a set of 4 units (each unit corresponds to 2 co-aligned cameras) arranged in arch, covering a field of view at zero response of 180°× 90°, and one more unit pointing to the anti-sun direction. The structure of each camera lies on its own coded mask of Tungsten, 150 μm thick, a collimator and the detector plane (20 cm below the mask) providing a fine (arc minutes) angular resolution. The camera detector plane (182 cm^2) will operate at -20°C in order to achieve an energy resolution FWHM of less than 500 eV in the 2-50 keV energy range. The WFM has the main scope of catching good triggering sources to be pointed with the LAD. Its large field of view will permit to observe in the same energy range of the LAD about 50% of the sky at once. The WFM is designed also to catch transient/bursting events down to a few mCrab fluxes and will provide for them data with fine spectral and timing resolution (up to 10 μsec).

Quantifying the Reproducibility of Heart Position During Treatment and Corresponding Delivered Heart Dose in Voluntary Deep Inhalation Breath Hold for Left Breast Cancer Patients Treated With External Beam Radiotherapy

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

McIntosh, Alyson; Shoushtari, Asal N.; Benedict, Stanley H.

Purpose: Voluntary deep inhalation breath hold (VDIBH) reduces heart dose during left breast irradiation. We present results of the first study performed to quantify reproducibility of breath hold using bony anatomy, heart position, and heart dose for VDIBH patients at treatment table. Methods and Materials: Data from 10 left breast cancer patients undergoing VDIBH whole-breast irradiation were analyzed. Two computed tomography (CT) scans, free breathing (FB) and VDIBH, were acquired to compare dose to critical structures. Pretreatment weekly kV orthogonal images and tangential ports were acquired. The displacement difference from spinal cord to sternum across the isocenter between coregistered planningmore » Digitally Reconstructed Radiographs (DRRs) and kV imaging of bony thorax is a measure of breath hold reproducibility. The difference between bony coregistration and heart coregistration was the measured heart shift if the patient is aligned to bony anatomy. Results: Percentage of dose reductions from FB to VDIBH: mean heart dose (48%, SD 19%, p = 0.002), mean LAD dose (43%, SD 19%, p = 0.008), and maximum left anterior descending (LAD) dose (60%, SD 22%, p = 0.008). Average breath hold reproducibility using bony anatomy across the isocenter along the anteroposterior (AP) plane from planning to treatment is 1 (range, 0-3; SD, 1) mm. Average heart shifts with respect to bony anatomy between different breath holds are 2 {+-} 3 mm inferior, 1 {+-} 2 mm right, and 1 {+-} 3 mm posterior. Percentage dose changes from planning to delivery: mean heart dose (7%, SD 6%); mean LAD dose, ((9%, SD 7%)S, and maximum LAD dose, (11%, SD 11%) SD 11%, p = 0.008). Conclusion: We observed excellent three-dimensional bony registration between planning and pretreatment imaging. Reduced delivered dose to heart and LAD is maintained throughout VDIBH treatment.« less

Validation, Intrarater and Interrater Reliability Study of the Lateral-Anterior Drawer Test for Detecting Posterior Cruciate Ligament Ruptures: Study Protocol of a Prospective Controlled Single-Blinded Cross-Sectional Study.

PubMed

Seeber, Gesine H; Thalhamer, Christoph; Hahne, Julia; Matthijs, Omer

2018-05-29

Commonly used clinical tests for posterior cruciate ligament (PCL) rupture detection exhibit several limitations, thus requiring more precise clinical PCL tests. The lateral-anterior drawer (LAD) test has been proposed as a manually applied testing alternative but not yet been evaluated in vivo. Fifteen patients presenting with an MRI-confirmed acute or chronic unilateral PCL rupture and 15 subjects with no prior knee injury in their medical history will be included in this prospective single-blinded cross-sectional cohort study. Three examiners with different lengths of working experience (range 1-30 years), blinded to MRI outcomes and patient history, will use the LAD test on both knees of each participant to test for PCL integrity. Examiners will independently document the PCL status of each knee on a blank case report form. Fleiss-Kappa values will be calculated to investigate whether the LAD test shows clinically significant interrater and intrarater reliability. Furthermore, LAD test outcomes will be compared with MRI which serves as reference standard to check for concurrent validity. Moreover, LAD test accuracy with respect to tester experience will be evaluated. The study will be conducted in agreement with the World Medical Association Declaration of Helsinki (2013). Ethical permission (EK16-081-0616) to conduct this study was obtained from the review board of the city of Vienna on 1 September 2016. All personal and research data will be used in accordance with the Austrian Federal Data Protection Act and will be anonymised before publication in relevant international peer-reviewed journals. DRKS00013268; Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A Randomized Controlled Trial Comparing the Letter Project Advance Directive to Traditional Advance Directive.

PubMed

Periyakoil, Vyjeyanthi S; Neri, Eric; Kraemer, Helena

2017-09-01

Simpler alternatives to traditional advance directives that are easy to understand and available in multiple formats and can be initiated by patients and families will help facilitate advance care planning. The goal of this study was to compare the acceptability of the letter advance directive (LAD) to the traditional advance directive (TAD) of the state of California. A web-based, randomized controlled trial was conducted, in which the participants were randomized to one of two types of advance directives (ADs): the LAD (intervention) or the TAD (control). Primary outcomes were participant ratings of the ease, value, and their level of comfort in the AD document they completed. A total of 400 participants completed the study, with 216 randomized to the LAD and 184 to the TAD by a computerized algorithm. Overall, participants preferred the LAD to the TAD (success rate difference [SRD] = 0.46, 95th percentile confidence interval [CI]: 0.36-0.56, p < 0.001). The participants felt that, compared to the TAD, the LAD was easier to read and understand (SRD = 0.56, CI: 0.47-0.65, p < 0.001); better reflected what matters most to them (SRD = 0.39, CI: 0.29-0.48, p < 0.001); helped stimulate their thinking about the types of treatments they wanted at the end of life (SRD = 0.32, CI: 0.23-0.42, p < 0.001); allowed them to describe how they made medical decisions in their family (SRD = 0.31, CI: 0.21-0.40, p < 0.001); and could help their doctor(s) (SRD = 0.24, CI: 0.13-0.34, p < 0.001) and their families (SRD = 0.19, CI: 0.08-0.28, p < 0.001) understand their end-of-life treatment preferences. Patients reported the letter advance directive to be a better alternative to the traditional advance directive form.

Lamina-Associated Domains: Links with Chromosome Architecture, Heterochromatin, and Gene Repression.

PubMed

van Steensel, Bas; Belmont, Andrew S

2017-05-18

In metazoan cell nuclei, hundreds of large chromatin domains are in close contact with the nuclear lamina. Such lamina-associated domains (LADs) are thought to help organize chromosomes inside the nucleus and have been associated with gene repression. Here, we discuss the properties of LADs, the molecular mechanisms that determine their association with the nuclear lamina, their dynamic links with other nuclear compartments, and their proposed roles in gene regulation. Copyright © 2017 Elsevier Inc. All rights reserved.

Louisiana SIP: LAC 33:III Ch. 5 Section 509. Prevention of Significant Deterioration; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) and 1991-07-01 (LAc57) and 1996-12-16 (LAc69) to 2011-08-17 (LAd36 - Revised)

EPA Pesticide Factsheets

Louisiana SIP: LAC 33:III Ch. 5 Section 509. Prevention of Significant Deterioration; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) and 1991-07-01 (LAc57) and 1996-12-16 (LAc69) to 2011-08-17 (LAd36 - Revised)

Louisiana SIP: LAC 33:III Ch 61 Subchap A, §6121 to § 6131--Method 43 - Capture Efficiency Test Procedures; SIP effective 1994-06-06 (LAc60) to to 2011-08-03 (LAd34 - Moved to Chap 21 Subchap N §§ 2155-2160 and revised)

EPA Pesticide Factsheets

Louisiana SIP: LAC 33:III Ch 61 Subchap A, §6121 to § 6131--Method 43 - Capture Efficiency Test Procedures; SIP effective 1994-06-06 (LAc60) to to 2011-08-03 (LAd34 - Moved to Chap 21 Subchap N §§ 2155-2160 and revised)

Louisiana SIP: LAC 33:III Ch. 7 - Table 2 - Ambient Air--Methods of Contaminant Measurements; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) to 2011-08-03 (LAd34 - Moved to Section 711 and revised [adds PM-2.5])

EPA Pesticide Factsheets

Louisiana SIP: LAC 33:III Ch. 7 - Table 2 - Ambient Air--Methods of Contaminant Measurements; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) to 2011-08-03 (LAd34 - Moved to Section 711 and revised [adds PM-2.5])

Louisiana SIP: LAC 33:III Ch. 7 Section 709. Measurement of Concentrations PM10, SO2, Carbon Monoxide, Atmospheric Oxidants, Nitrogen Oxides, and Lead; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) to 2011-08-03 (LAd34 - Revised)

EPA Pesticide Factsheets

Louisiana SIP: LAC 33:III Ch. 7 Section 709. Measurement of Concentrations PM10, SO2, Carbon Monoxide, Atmospheric Oxidants, Nitrogen Oxides, and Lead; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) to 2011-08-03 (LAd34 - Revised)

Lyophilized artificial diet for rearing the Neotropical Euschistus heros (Hemiptera: Pentatomidae)

PubMed Central

Mendoza, Agustín C.; da Rocha, Aline C. P.

2016-01-01

An artificial diet to mass-rear Euschistus heros (F. 1798) (Hemiptera: Pentatomidae) was developed in the laboratory. Biological studies were conducted under controlled conditions of temperature (25 ± 2°C), RH: 60 ± 10%, and photoperiod of 14:10 (L:D) h. Out of 13 diets tested, 2 diets (D9 and D11) were the most suitable. The artificial diets selected had the same composition (green beans, peanuts, sucrose, water, Nipagin, and sorbic acid) except for different antimicrobial agents (D11 has tetracycline, and D9 doesn’t). The 68% viability for the egg–adult period of insects reared on these lyophilized artificial diets (LAD) was almost twice as high as the 38% viability obtained with the natural diet. Although adults reared on LAD weighed 17% less than those reared on the natural diet, mean fecundity was higher than on the natural diet (282 eggs/female), reaching 430 eggs/female. The net reproductive rate (Ro) increased over the generations for the diets with lyophilized material and antimicrobial agents. The opposite occurred with the diet of lyophilized material without antimicrobial agents, showing that the insects either adapted or degenerated through generations. Lyophilized diets supported the production of E. heros through at least 10 generations, with no degeneration. PMID:27126964

Lidocaine inhibits the proliferation of lung cancer by regulating the expression of GOLT1A.

PubMed

Zhang, Lei; Hu, Rong; Cheng, Yanyong; Wu, Xiaoyang; Xi, Siwei; Sun, Yu; Jiang, Hong

2017-10-01

Lidocaine is the most commonly used local anaesthetic in clinical and can inhibit proliferation, suppress invasion and migration and induce apoptosis in human lung adenocarcinoma (LAD) cells. However, its specific downstream molecular mechanism is unclear. LAD cell lines, A549 and H1299 cells, were treated with lidocaine. The proliferation was evaluated by the methylthiazolyldiphenyl-tetrazolium bromide (MTT) and bromodeoxyuridine (BrdU) assay. The expression level of related proteins was detected by real-time quantitative PCR (qPCR) and Western blot assay. The results indicated that lidocaine dose-dependently suppressed the proliferation of A549 and H1299 cells. In the LAD patients' samples, GOLT1A was upregulated and involved in the poor prognosis and higher grade malignancy. Additionally, GOLT1A mediates the function of lidocaine on repressing proliferation by regulating the cell cycle in A549 cells. Our findings suggest that lidocaine downregulates the GOLT1A expression to repress the proliferation of lung cancer cells. © 2017 John Wiley & Sons Ltd.

Proposed US Contributions to LOFT

NASA Technical Reports Server (NTRS)

Wilson-Hodge, Colleen

2013-01-01

Proposed US Enhancements include:Tantalum X -ray collimator, Additional ground station, Large Observatory for X-Ray Timing (LOFT) instrument team participation, US science support center & data archive, and Science enabled by US hardware. High-Z material with excellent stopping power. Fabricated using a combination of laser micromachining and chemical etching. Known technology capable of producing high-aspect ratio holes and large open fractions. Reduces LOFT LAD background by a factor of 3. Telemetry formats for LOFT based upon RXTE/EDS experience. Ground system software and strategies for WFM based upon RXTE/ASM automated pipeline software. MSFC engineering trade studies supporting the Ta collimator. Burst alert triggers based upon Fermi/GBM and HETE-2. Science Enhancements Enabled by US Hardware include: Tantalum collimator: Reduces background by factor of 3. Improves sensitivity to faint sources such as AGN. Eliminates contamination by bright/variable sources. outside the LAD field of view. US Ground Station: Enables continuous telemetry of all events from the WFM. Allows LAD to observe very bright >500 mCrab sources with full event resolution.

Polar motion excitation analysis due to global continental water redistribution

NASA Astrophysics Data System (ADS)

Fernandez, L.; Schuh, H.

2006-10-01

We present the results obtained when studying the hydrological excitation of the Earth‘s wobble due to global redistribution of continental water storage. This work was performed in two steps. First, we computed the hydrological angular momentum (HAM) time series based on the global hydrological model LaD (Land Dynamics model) for the period 1980 till 2004. Then, we compared the effectiveness of this excitation by analysing the residuals of the geodetic time series after removing atmospheric and oceanic contributions with the respective hydrological ones. The emphasis was put on low frequency variations. We also present a comparison of HAM time series from LaD with respect to that one from a global model based on the assimilated soil moisture and snow accumulation data from NCEP/NCAR (The National Center for Environmental Prediction/The National Center for Atmospheric Research) reanalysis. Finally, we evaluate the performance of LaD model in closing the polar motion budget at seasonal periods in comparison with the NCEP and the Land Data Assimilation System (LDAS) models.

Distribution of coronary arterial capacitance in a canine model.

PubMed

Lader, A S; Smith, R S; Phillips, G C; McNamee, J E; Abel, F L

1998-03-01

The capacitative properties of the major left coronary arteries, left main (LM), left anterior descending (LAD), and left circumflex (LCX), were studied in 19 open-chest isolated dog hearts. Capacitance was determined by using ramp perfusion and a left ventricular-to-coronary shunt diastolic decay method; both methods gave similar results, indicating a minimal systolic capacitative component. Increased pericardial pressure (PCP), 25 mmHg, was used to experimentally alter transmural wall pressure. The response to increased PCP was different in the LAD vs. LCX; increasing PCP decreased capacitance in the LCX but increased capacitance in the LAD. This may have been due to the different intramural vs. epicardial volume distribution of these vessels and a decrease in intramural tension during increased PCP. Increased PCP decreased LCX capacitance by approximately 13%, but no changes in conductance or zero flow pressure intercept occurred in any of the three vessels, i. e., evidence against the waterfall theory of vascular collapse at these levels of PCP. Coronary arterial capacitance was also linearly related to perfusion pressure.

Biogas energy production from tropical biomass wastes by anaerobic digestion.

PubMed

Ge, Xumeng; Matsumoto, Tracie; Keith, Lisa; Li, Yebo

2014-10-01

Anaerobic digestion (AD) is an attractive technology in tropical regions for converting locally abundant biomass wastes into biogas which can be used to produce heat, electricity, and transportation fuels. However, investigations on AD of tropical forestry wastes, such as albizia biomass and food wastes, such as taro, papaya, and sweet potato, are limited. In this study, these tropical biomass wastes were evaluated for biogas production by liquid AD (L-AD) and/or solid-state AD (SS-AD), depending on feedstock characteristics. When albizia leaves and chips were used as feedstocks, L-AD had greater methane yields (161 and 113 L kg(-1)VS, respectively) than SS-AD (156.8 and 59.6 L kg(-1)VS, respectively), while SS-AD achieved 5-fold higher volumetric methane productivity than L-AD. Mono-digestion and co-digestion of taro skin, taro flesh, papaya, and sweet potato achieved methane yields from 345 to 411 L kg(-1)VS, indicating the robustness of AD technology. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of different ratios of feedstock to liquid anaerobic digestion effluent on the performance and microbiome of solid-state anaerobic digesters digesting corn stover.

PubMed

Li, Yueh-Fen; Shi, Jian; Nelson, Michael C; Chen, Po-Hsu; Graf, Joerg; Li, Yebo; Yu, Zhongtang

2016-01-01

The objective of this study was to understand how the non-microbial factors of L-AD effluent affected the microbiome composition and successions in the SS-AD digesters using both Illumina sequencing and qPCR quantification of major genera of methanogens. The SS-AD digesters started with a feedstock/total effluent (F/Et) ratio 2.2 (half of the effluent was autoclaved) performed stably, while the SS-AD digesters started with a 4.4 F/Et ratio (no autoclaved effluent) suffered from digester acidification, accumulation of volatile fatty acids, and ceased biogas production two weeks after startup. Some bacteria and methanogens were affected by non-microbial factors of the L-AD fluent. Alkalinity, the main difference between the two F/Et ratios, may be the crucial factor when SS-AD digesters were started using L-AD effluent. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bovine Intestinal Alkaline Phosphatase Reduces Inflammation After Induction of Acute Myocardial Infarction in Mice

PubMed Central

Fiechter, Danielle; Kats, Suzanne; Brands, Ruud; van Middelaar, Ben; Pasterkamp, Gerard; de Kleijn, Dominique; Seinen, Willem

2011-01-01

Background There has been increasing evidence suggesting that lipopolysaccharide or endotoxin may be an important activator of the innate immune system after acute myocardial infarction. Bovine intestinal alkaline phosphatase reduces inflammation in several endotoxin mediated diseases by dephosphorylation of the lipid A moiety of lipopolysaccharide. The aim of this study was to investigate the effect of bovine intestinal alkaline phosphatase on reducing inflammation after acute myocardial infarction. Methods Just before permanent ligation of the left anterior descending coronary (LAD) artery to induce acute myocardial infarction in Balb/c mice, bovine intestinal alkaline phosphatase (bIAP) was administrated intravenously. After 4 hours, mice were sacrificed and the inflammatory response was assessed. Acute myocardial infarction induced the production of different cytokines, which were measured in blood. Results Treatment with bovine intestinal alkaline phosphatase resulted in a significant reduction of the pro-inflammatory cytokines IL-6, IL-1β and the chymase mouse mast cell protease-1. No difference in the production of the anti-inflammatory cytokine IL-10 was observed between the control group and the bovine intestinal alkaline phosphatase treated group. Conclusion In a mouse model of permanent LAD coronary artery ligation, bIAP diminishes the pro-inflammatory responses but does not have an effect on the anti-inflammatory response in the acute phase after acute myocardial infarction. PMID:28357012

Cardiac dose reduction with deep inspiration breath hold for left-sided breast cancer radiotherapy patients with and without regional nodal irradiation.

PubMed

Yeung, Rosanna; Conroy, Leigh; Long, Karen; Walrath, Daphne; Li, Haocheng; Smith, Wendy; Hudson, Alana; Phan, Tien

2015-09-22

Deep inspiration breath hold (DIBH) reduces heart and left anterior descending artery (LAD) dose during left-sided breast radiation therapy (RT); however there is limited information about which patients derive the most benefit from DIBH. The primary objective of this study was to determine which patients benefit the most from DIBH by comparing percent reduction in mean cardiac dose conferred by DIBH for patients treated with whole breast RT ± boost (WBRT) versus those receiving breast/chest wall plus regional nodal irradiation, including internal mammary chain (IMC) nodes (B/CWRT + RNI) using a modified wide tangent technique. A secondary objective was to determine if DIBH was required to meet a proposed heart dose constraint of Dmean < 4 Gy in these two cohorts. Twenty consecutive patients underwent CT simulation both free breathing (FB) and DIBH. Patients were grouped into two cohorts: WBRT (n = 11) and B/CWRT + RNI (n = 9). 3D-conformal plans were developed and FB was compared to DIBH for each cohort using Wilcoxon signed-rank tests for continuous variables and McNemar's test for discrete variables. The percent relative reduction conferred by DIBH in mean heart and LAD dose, as well as lung V20 were compared between the two cohorts using Wilcox rank-sum testing. The significance level was set at 0.05 with Bonferroni correction for multiple testing. All patients had comparable target coverage on DIBH and FB. DIBH statistically significantly reduced mean heart and LAD dose for both cohorts. Percent reduction in mean heart and LAD dose with DIBH was significantly larger in the B/CWRT + RNI cohort compared to WBRT group (relative reduction in mean heart and LAD dose: 55.9 % and 72.1 % versus 29.2 % and 43.5 %, p < 0.02). All patients in the WBRT group and five patients (56 %) in the B/CWBRT + RNI group met heart Dmean <4 Gy with FB. All patients met this constraint with DIBH. All patients receiving WBRT met Dmean Heart < 4 Gy on FB, while only slightly over half of patients receiving B/CWRT + RNI were able to meet this constraint in FB. DIBH allowed a greater reduction in mean heart and LAD dose in patients receiving B/CWRT + RNI, including IMC nodes than patients receiving WBRT. These findings suggest greatest benefit from DIBH treatment for patients receiving regional nodal irradiation.

The Human Operator Simulator. Volume IX. HOS Study Guide.

DTIC Science & Technology

1978-09-01

Ad - 969*91 - 0 0 0 0 0 0 C L.J0 L.J0 - L.i0 LAdO - L~0 wO 0In dJO LAd0 16 1.dQ -WO I ~ PW0 U ~ ~. 46W 4~(.J .* - 4~~Ad 414 4’~ 4~J - 2 ~ ~ T - 4 6J0...only developed from a specific need, but it also grew out of what I consider to be an unusual and fortuitous series of experi- ences to which I had been

[Surgical cryoablation and left ventriculoplasty for electrical storm after acute myocardial infarction].

PubMed

Tobe, Satoshi; Yoshida, K; Adachi, K; Fukase, K; Tanimura, N; Yamaguchi, M

2008-03-01

A 65-year-old man was referred to our hospital to treat recent anterior myocardial infarction. Coronary artery angiography showed acute occlusion of left anterior descending coronary artery (LAD) and chronic occlusion of right coronary artery. After emergent percutaneous coronary intervention for LAD, drug-refractory electrical storm necessitating frequent electrical defibrillating cardioversion occurred. This patient successfully underwent surgical cryoablation, left ventriculoplasty and coronary revascularization. At 2 years and 10th month after the operation, he is well without limitation of daily activities and any evidence of myocardial ischemia and ventricular tachycardia.

Potential Sources of Polarized Light from a Plant Canopy

NASA Technical Reports Server (NTRS)

Vanderbilt, Vern; Daughtry, Craig; Dahlgren, Robert

2016-01-01

Field measurements have demonstrated that sunlight polarized during a first surface reflection by shiny leaves dominates the optical polarization of the light reflected by shiny-leafed plant canopies having approximately spherical leaf angle probability density functions ("Leaf Angle Distributions" - LAD). Yet for other canopies - specifically those without shiny leaves and/or spherical LADs - potential sources of optically polarized light may not always be obvious. Here we identify possible sources of polarized light within those other canopies and speculate on the ecologically important information polarization measurements of those sources might contain.

[Revascularization of left anterior descending artery area using a skeletonized left internal mammary artery: a comparison between sequential and separate grafting].

PubMed

Shen, J Q; Ji, Q; Ding, W J; Xia, L M; Wei, L; Wang, C S

2018-03-13

Objective: To evaluate in-hospital and mid-term outcomes of sequential versus separate grafting of in situ skeletonized left internal mammary artery (LIMA) to the left coronary system in a single-center, propensity-matched study. Methods: After propensity score matching, 120 pairs of patients undergoing first, scheduled, isolated coronary artery bypass grafting (CABG) with in situ skeletonized LIMA grafting to the left anterior descending artery (LAD) territory were entered into a sequential group (sequential grafting of LIMA to the diagonal artery and then to the LAD) or a control group (separate grafting of LIMA to the LAD). The in-hospital and follow-up clinical outcomes and follow-up LIMA graft patency were compared. Results: The two propensity score-matched groups had similar in-hospital and follow-up clinical outcomes. The number of bypass conduits ranged from 3 to 6 (with a mean of 3.5), and 91.3%(219/240)of the included patients received off-pump CABG surgery. No significant differences were found between the two propensity score-matched groups in the in-hospital outcomes, including in-hospital death and the incidence of complications associated with CABG (prolonged ventilation, peroperative stroke, re-operation before discharge, and deep sternal wound infection). During follow-up, 9 patients (4 patients from the sequential group and 5 patients from the control group) died, and the all-cause mortality rate was 3.9%. No significant difference was found in the all-cause mortality rate between the 2 groups[3.4% (4/116) vs 4.3% (5/115), P =0.748]. During follow-up period, 99.1% (115/116) patency for the diagonal site and 98.3% (114/116) for the LAD site were determined by coronary computed tomographic angiography after sequential LIMA grafting, both of which were similar with graft patency of separate grafting of in situ skeletonized LIMA to the LAD. Conclusions: Revascularization of the left coronary system using a skeletonized LIMA resulted in excellent in-hospital and mid-term clinical outcomes and graft patency using sequential grafting.

Induction of a chronic myocardial infarction in the laboratory animal - experimental model

PubMed Central

POP, IONEL CIPRIAN; GRAD, NICOLAE-OVIDIU; PESTEAN, COSMIN; TAULESCU, MARIAN; MIRCEAN, MIRCEA; MIRONIUC, ION-AUREL

2013-01-01

Introduction Ischemic heart disease is a major public health problem in western countries. Appropriate animal experimental models of chronic myocardial infarction is an essential first step in order to investigate and develop new therapeutic interventions. Aim The aim of this study was to find an optimal place for a coronary artery ligation to induce an optimal chronic myocardial infarction and also a new heart approach that will not require oro-tracheal intubation. Material and methods To achieve these goals we used a group of rabbits and after induction of anesthesia and cardiac exposure by rib osteotomy (rib III, IV and V) at the costo-sternal junction level on the right side we performed three different left anterior descending artery (LAD) ligation at different distances (5, 10 and 15 mm) in relation to the apex. Thirty days after the acute myocardial infarction, we correlated laboratory investigations (serology, ECG, cardiac ultrasound) with histopathological findings. Results Heart approach achieved by rib osteotomy (rib III, IV and V) at the costo-sternal junction level on the right side, maintains the integrity of the ribcage, allowing it to take part in respiratory movements and the animal model does not need oro-tracheal intubation. Ligation of LAD at 15 mm from the apex was incompatible with life; ligation of LAD at 5 mm from the apex does not achieved transmural myocardial infarction and ligation of LAD at 10 mm from the apex achieved a transmural myocardial infarction of the left ventricle which also involved the distal part of the interventricular septum. Conclusion Ligation of LAD at 10 mm from the apex achieved a transmural myocardial infarction of the left ventricle, is in an easily accessible area from technical point of view, it is sufficiently expanded to induce hemodynamic effects that can be quantified with paraclinical examination and also it is compatible with the experimental animal life. If the heart is approached by rib III, IV and V osteotomy at the costo-sternal junction level on the right side combined with neuroleptic anaesthesia, the animal does not need assisted ventilation. PMID:26527973

Assessing radiation exposure of the left anterior descending artery, heart and lung in patients with left breast cancer: A dosimetric comparison between multicatheter accelerated partial breast irradiation and whole breast external beam radiotherapy.

PubMed

Chan, Tabitha Y; Tan, Poh Wee; Tan, Chek Wee; Tang, Johann I

2015-12-01

This study aims to quantify dosimetric reduction to the left anterior descending (LAD) artery, heart and lung when comparing whole breast external beam radiotherapy (WBEBRT) with multicatheter accelerated partial breast irradiation (MCABPI) for early stage left breast cancer. Planning CT data sets of 15 patients with left breast cancer receiving multicatheter brachytherapy post breast conserving surgery were used to create two independent treatment plans - WBEBRT prescribed to 50 Gy/25 fractions and MCABPI prescribed to 34 Gy/10 fractions. Dose parameters for (i) LAD artery, (ii) heart, and (iii) ipsilateral lung were calculated and compared between the two treatment modalities. After adjusting for Equivalent Dose in 2 Gy fractions(EQD2), and comparing MCAPBI with WBEBRT, the largest dose reduction was for the LAD artery whose mean dose differed by a factor of 7.7, followed by the ipsilateral lung and heart with a factor of 4.6 and 2.6 respectively. Compared to WBEBRT, the mean MCAPBI LAD was significantly lower compared to WBEBRT (6.0 Gy vs 45.9 Gy; p<0.01). Mean MCAPBI heart D(0.1cc) (representing the dose received by the most highly exposed 0.1 cc of the risk organ, i.e. the dose peak) was significantly lower (16.3 Gy vs 50.6 Gy; p<0.01). Likewise, the mean heart dose (MHD) was significantly lower (2.3 Gy vs 6.0 Gy; p<0.01). Peak dose and mean lung dose (MLD) for ipsilateral lung was also lower for MCAPBI compared to WBEBRT (Peak dose: 22.2 Gy vs 52.0 Gy; p<0.01; MLD: 2.3 Gy vs 10.7 Gy; p<0.01). Compared to WBEBRT, MCAPBI showed a significant reduction in radiation dose for the LAD, heart and lung. This may translate into better cardiac and pulmonary toxicities for patients undergoing MCAPBI. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Impact of functional focal versus diffuse coronary artery disease on bypass graft patency.

PubMed

Shiono, Yasutsugu; Kubo, Takashi; Honda, Kentaro; Katayama, Yosuke; Aoki, Hiroshi; Satogami, Keisuke; Kashiyama, Kuninobu; Taruya, Akira; Nishiguchi, Tsuyoshi; Kuroi, Akio; Orii, Makoto; Kameyama, Takeyoshi; Yamano, Takashi; Yamaguchi, Tomoyuki; Matsuo, Yoshiki; Ino, Yasushi; Tanaka, Atsushi; Hozumi, Takeshi; Nishimura, Yoshiharu; Okamura, Yoshitaka; Akasaka, Takashi

2016-11-01

Pressure guidewire pullback recording can differentiate between functional focal and diffuse disease types in coronary artery disease. The aim of this study was to compare the outcome of coronary artery bypass graft (CABG) patency between patients with functional focal versus diffuse disease types in recipient coronary arteries. We investigated 89 patients who underwent pressure guidewire pullback in the left anterior descending (LAD) artery before CABG using internal mammary artery (IMA). Based on the pressure guidewire pullback data, the LAD lesions were classified into functional focal disease (abrupt pressure step-up; n=58) or functional diffuse disease (gradual pressure increase; n=31). Follow-up computed tomography (CT) angiography was conducted within 1year after CABG to assess the bypass graft patency. Pre CABG, LAD angiographic percent diameter stenosis (57±10% vs. 54±12%, p=0.228) and fractional flow reserve (FFR) (0.68±0.07 vs. 0.69±0.07, p=0.244) were not different between the functional focal and diffuse disease groups. The CABG procedure characteristics were similarly comparable between the two groups. In the follow-up CT angiography after CABG, occlusion or string sign of the IMA graft to LAD was more frequently observed in the functional diffuse disease group than in the functional focal disease group (26% vs. 7%, p=0.021). In CABG, functional diffuse disease in the recipient coronary artery was associated with an increased risk of the graft failure in comparison with functional focal disease. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Automated CT Scan Scores of Bronchiectasis and Air Trapping in Cystic Fibrosis

PubMed Central

Swiercz, Waldemar; Heltshe, Sonya L.; Anthony, Margaret M.; Szefler, Paul; Klein, Rebecca; Strain, John; Brody, Alan S.; Sagel, Scott D.

2014-01-01

Background: Computer analysis of high-resolution CT (HRCT) scans may improve the assessment of structural lung injury in children with cystic fibrosis (CF). The goal of this cross-sectional pilot study was to validate automated, observer-independent image analysis software to establish objective, simple criteria for bronchiectasis and air trapping. Methods: HRCT scans of the chest were performed in 35 children with CF and compared with scans from 12 disease control subjects. Automated image analysis software was developed to count visible airways on inspiratory images and to measure a low attenuation density (LAD) index on expiratory images. Among the children with CF, relationships among automated measures, Brody HRCT scanning scores, lung function, and sputum markers of inflammation were assessed. Results: The number of total, central, and peripheral airways on inspiratory images and LAD (%) on expiratory images were significantly higher in children with CF compared with control subjects. Among subjects with CF, peripheral airway counts correlated strongly with Brody bronchiectasis scores by two raters (r = 0.86, P < .0001; r = 0.91, P < .0001), correlated negatively with lung function, and were positively associated with sputum free neutrophil elastase activity. LAD (%) correlated with Brody air trapping scores (r = 0.83, P < .0001; r = 0.69, P < .0001) but did not correlate with lung function or sputum inflammatory markers. Conclusions: Quantitative airway counts and LAD (%) on HRCT scans appear to be useful surrogates for bronchiectasis and air trapping in children with CF. Our automated methodology provides objective quantitative measures of bronchiectasis and air trapping that may serve as end points in CF clinical trials. PMID:24114359

Directed targeting of chromatin to the nuclear lamina is mediated by chromatin state and A-type lamins.

PubMed

Harr, Jennifer C; Luperchio, Teresa Romeo; Wong, Xianrong; Cohen, Erez; Wheelan, Sarah J; Reddy, Karen L

2015-01-05

Nuclear organization has been implicated in regulating gene activity. Recently, large developmentally regulated regions of the genome dynamically associated with the nuclear lamina have been identified. However, little is known about how these lamina-associated domains (LADs) are directed to the nuclear lamina. We use our tagged chromosomal insertion site system to identify small sequences from borders of fibroblast-specific variable LADs that are sufficient to target these ectopic sites to the nuclear periphery. We identify YY1 (Ying-Yang1) binding sites as enriched in relocating sequences. Knockdown of YY1 or lamin A/C, but not lamin A, led to a loss of lamina association. In addition, targeted recruitment of YY1 proteins facilitated ectopic LAD formation dependent on histone H3 lysine 27 trimethylation and histone H3 lysine di- and trimethylation. Our results also reveal that endogenous loci appear to be dependent on lamin A/C, YY1, H3K27me3, and H3K9me2/3 for maintenance of lamina-proximal positioning. © 2015 Harr et al.

Genome-wide maps of nuclear lamina interactions in single human cells.

PubMed

Kind, Jop; Pagie, Ludo; de Vries, Sandra S; Nahidiazar, Leila; Dey, Siddharth S; Bienko, Magda; Zhan, Ye; Lajoie, Bryan; de Graaf, Carolyn A; Amendola, Mario; Fudenberg, Geoffrey; Imakaev, Maxim; Mirny, Leonid A; Jalink, Kees; Dekker, Job; van Oudenaarden, Alexander; van Steensel, Bas

2015-09-24

Mammalian interphase chromosomes interact with the nuclear lamina (NL) through hundreds of large lamina-associated domains (LADs). We report a method to map NL contacts genome-wide in single human cells. Analysis of nearly 400 maps reveals a core architecture consisting of gene-poor LADs that contact the NL with high cell-to-cell consistency, interspersed by LADs with more variable NL interactions. The variable contacts tend to be cell-type specific and are more sensitive to changes in genome ploidy than the consistent contacts. Single-cell maps indicate that NL contacts involve multivalent interactions over hundreds of kilobases. Moreover, we observe extensive intra-chromosomal coordination of NL contacts, even over tens of megabases. Such coordinated loci exhibit preferential interactions as detected by Hi-C. Finally, the consistency of NL contacts is inversely linked to gene activity in single cells and correlates positively with the heterochromatic histone modification H3K9me3. These results highlight fundamental principles of single-cell chromatin organization. VIDEO ABSTRACT. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison of solid-state to liquid anaerobic digestion of lignocellulosic feedstocks for biogas production.

PubMed

Brown, Dan; Shi, Jian; Li, Yebo

2012-11-01

Lignocellulosic biomass feedstocks (switchgrass, corn stover, wheat straw, yard waste, leaves, waste paper, maple, and pine) were evaluated for methane production under liquid anaerobic digestion (L-AD) and solid-state anaerobic digestion (SS-AD). No significant difference in methane yield between L-AD and SS-AD, except for waste paper and pine, were found. However, the volumetric productivity was 2- to 7-fold greater in the SS-AD system compared with the L-AD system, except for paper. Methane yields from corn stover, wheat straw, and switchgrass were 2-5 times higher than those from yard waste, maple, and pine biomass. Waste paper had a methane yield of only 15 L/kg VS caused by souring during SS-AD due to organic overloading. Pine also had very low biogas yield of 17 L/kg VS, indicating the need for pretreatment prior to SS-AD. The findings of this study can guide future studies to improve the efficiency and stability of SS-AD of lignocellulosic biomass. Copyright © 2012 Elsevier Ltd. All rights reserved.

Improving The Near-Earth Meteoroid And Orbital Debris Environment Definition With LAD-C

NASA Technical Reports Server (NTRS)

Liou, J.-C.; Giovane, F. J.; Corsaro, R. C.; Burchell, M. J.; Drolshagen, G.; Kawai, H.; Tabata, M.; Stansbery, E. G.; Westphal, A. J.; Yano, H.

2006-01-01

To improve the near-Earth meteoroid and orbital debris environment definition, a large area particle sensor/collector is being developed to be placed on the International Space Station (ISS). This instrument, the Large Area Debris Collector (LAD-C), will attempt to record meteoroid and orbital debris impact flux, and capture the same particles with aerogel. After at least one year of deployment, the whole system will be brought back for additional laboratory analysis of the captured meteoroids and orbital debris. This project is led by the U.S. Naval Research Laboratory (NRL) while the U.S. Department of Defense (DoD) Space Test Program (STP) is responsible for the integration, deployment, and retrieval of the system. Additional contributing team members of the consortium include the NASA Orbital Debris Program Office, JAXA Institute of Space and Astronautical Science (ISAS), Chiba University (Japan), ESA Space Debris Office, University of Kent (UK), and University of California at Berkeley. The deployment of LAD-C on the ISS is planned for 2008, with the system retrieval in late 2009.

Warm Pressurant Gas Effects on the Static Bubble Point Pressure for Cryogenic LADs

NASA Technical Reports Server (NTRS)

Hartwig, Jason W.; McQuillen, John; Chato, Daniel J.

2014-01-01

This paper presents experimental results for the liquid hydrogen and nitrogen bubble point tests using warm pressurant gases conducted at the NASA Glenn Research Center. The purpose of the test series was to determine the effect of elevating the temperature of the pressurant gas on the performance of a liquid acquisition device (LAD). Three fine mesh screen samples (325x2300, 450x2750, 510x3600) were tested in liquid hydrogen and liquid nitrogen using cold and warm non-condensable (gaseous helium) and condensable (gaseous hydrogen or nitrogen) pressurization schemes. Gases were conditioned from 0K - 90K above the liquid temperature. Results clearly indicate degradation in bubble point pressure using warm gas, with a greater reduction in performance using condensable over non-condensable pressurization. Degradation in the bubble point pressure is inversely proportional to screen porosity, as the coarsest mesh demonstrated the highest degradation. Results here have implication on both pressurization and LAD system design for all future cryogenic propulsion systems. A detailed review of historical heated gas tests is also presented for comparison to current results.

Imaging of all three coronary arteries by transthoracic echocardiography. an illustrated guide

PubMed Central

Krzanowski, Marek; Bodzoń, Wojciech; Dimitrow, Paweł Petkow

2003-01-01

Background Improvements in ultrasound technology has enabled direct, transthoracic visualization of long portions of coronary arteries : the left anterior descending (LAD), circumflex (Cx) and right coronary artery (RCA). Transthoracic measurements of coronary flow velocity were proved to be highly reproducible and correlated with invasive measurements. While clinical applications of transthoracic echocardiography (TTE) of principal coronary arteries are still very limited they will likely grow. The echocardiographers may therefore be interested to know the ultrasonic views, technique of examination and be aware where to look for coronary arteries and how to optimize the images. Methods A step-by-step approach to direct, transthoracic visualization of the LAD, Cx and RCA is presented. The technique of examination is discussed, correlations with basic coronary angiography views and heart anatomy are shown and extensively illustrated with photographs and movie-pictures. Hints concerning optimization of ultrasound images are presented and artifacts of imaging are discussed. Conclusions Direct, transthoracic examination of the LAD, Cx and RCA in adults is possible and may become a useful adjunct to other methods of coronary artery examination but studies are needed to establish its role. PMID:14622441

FFR analysis of blood flow through a stenosed Left Anterior Descending Artery

NASA Astrophysics Data System (ADS)

Pasupathi, Jawahar; Arul Prakash, K.

2017-11-01

The numerical analyisis of blood flow through a stenosed tapering Left Anterior Descending (LAD) artery was done using Streamwise Upwind Petrov Galerkin (SUPG) method to obtain the clinical parameters such as Fractional Flow reserve (FFR) and Wall Shear Stress (WSS). The geometry was considered to be a straight tapering cylindrical duct with the severity of stenosis modeled using a curve equation based on the reduction in diameter at the stenosed region. Poiseuille velocity profile was given at the inlet such that at each time step the product of mean velocity and the inlet area gives the realistic flow rate through the LAD. The simulation was done for 30,50 and 70 percent reduction in cross-section of LAD. The average pressure values across the stenosis was used to quantify FFR. The FFR increased with higher pressure ratio across the stenosis, which is a result of increased severity of stenosis. The velocity gradients that are responsible for the shear stress at the walls were found to be dependent on the shape of the stenosis, i.e., the diameter and its length.

Genie in a blotter: A comparative study of LSD and LSD analogues' effects and user profile.

PubMed

Coney, Leigh D; Maier, Larissa J; Ferris, Jason A; Winstock, Adam R; Barratt, Monica J

2017-05-01

This study aimed to describe self-reported patterns of use and effects of lysergic acid diethylamide (LSD) analogues (AL-LAD, 1P-LSD, and ETH-LAD) and the characteristics of those who use them. An anonymous self-selected online survey of people who use drugs (Global Drug Survey 2016; N = 96,894), which measured perceived drug effects of LSD and its analogues. Most LSD analogue users (91%) had also tried LSD. The proportion of U.K. and U.S. respondents reporting LSD analogue use in the last 12 months was higher than for LSD only. LSD analogue users described the effects as psychedelic (93%), over half (55%) obtained it online, and almost all (99%) reported an oral route of administration. The modal duration (8 hr) and time to peak (2 hr) of LSD analogues were not significantly different from LSD. Ratings for pleasurable high, strength of effect, comedown, urge to use more drugs, value for money, and risk of harm following use were significantly lower for LSD analogues compared with LSD. LSD analogues were reported as similar in time to peak and duration as LSD but weaker in strength, pleasurable high, and comedown. Future studies should seek to replicate these findings with chemical confirmation and dose measurement. Copyright © 2017 John Wiley & Sons, Ltd.

Evaluation of sparing organs at risk (OARs) in left-breast irradiation in the supine and prone positions and with deep inspiration breath-hold.

PubMed

Saini, Amitpal Singh; Hwang, Catherine S; Biagioli, Matthew C; Das, Indra J

2018-06-21

To compare doses to organs at risk (OARs) for left-sided whole-breast radiation therapy with comparable planning target volume (PTV) coverage using three techniques: free breathing in a supine position (SFB), deep inspirational breath-hold in a supine position (SDIBH), and free breathing in prone position (PFB). Thirty-three patients with left-sided early-stage breast cancer underwent CT simulation following SFB, SDIBH, and PFB protocols for whole-breast radiation therapy. One radiation oncologist contoured the breast PTV, heart, left ventricle (LV), and left anterior descending artery (LAD). Treatment plans were optimized using field-in-field technique with the AAA algorithm. Each plan was optimized to provide identical coverage to the PTV such that a reasonable comparison for OAR dosimetry could be evaluated. All plans were prescribed 42.56 Gy in 16 fractions to the left-breast PTV. The mean dose in SFB for the heart, LV, and LAD was 1.92, 3.19, and 21.73 Gy, respectively, which were significantly higher than the mean dose in SDIBH for the heart (1.08 Gy, P ≤ 0.0001), LV (1.50 Gy, P ≤ 0.0001), and LAD (6.3 Gy, P ≤ 0.0001) and in PFB for the heart (0.98 Gy, P ≤ 0.0001), LV (1.34 Gy, P ≤ 0.0001), and LAD (6.57 Gy, P ≤ 0.0001). Similar findings were noted for the cardiac components in SFB for V2.5, V5, V10, V20, and V30 compared with values in SDIBH and PFB. The mean dose for the left lung in PFB was 0.61 Gy that was significantly lower than in SFB (5.63 Gy, P ≤ 0.0001) and SDIBH (5.54 Gy, P ≤ 0.0001). Mean dose and dosimetric values for each OAR increased in SFB and SDIBH for patients with a large breast volume compared with values for patients with a small breast volume. SFB results in higher heart, LAD, and LV doses than the other techniques. Both PFB and SDIBH are more advantageous for these OARs irrespective of breast volume. PFB results in significantly lower lung doses than SFB and SDIBH. PFB always provided better results than SFB for the heart, LV, LAD, and lung. This conclusion contrasts with some published studies concluding that the prone position has no benefit for heart sparing. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

A comparative analysis of 3D conformal deep inspiratory–breath hold and free-breathing intensity-modulated radiation therapy for left-sided breast cancer

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

Reardon, Kelli A.; Read, Paul W.; Morris, Monica M.

2013-07-01

Patients undergoing radiation for left-sided breast cancer have increased rates of coronary artery disease. Free-breathing intensity-modulated radiation therapy (FB-IMRT) and 3-dimensional conformal deep inspiratory–breath hold (3D-DIBH) reduce cardiac irradiation. The purpose of this study is to compare the dose to organs at risk in FB-IMRT vs 3D-DIBH for patients with left-sided breast cancer. Ten patients with left-sided breast cancer had 2 computed tomography scans: free breathing and voluntary DIBH. Optimization of the IMRT plan was performed on the free-breathing scan using 6 noncoplanar tangential beams. The 3D-DIBH plan was optimized on the DIBH scan and used standard tangents. Mean volumesmore » of the heart, the left anterior descending coronary artery (LAD), the total lung, and the right breast receiving 5% to 95% (5% increments) of the prescription dose were calculated. Mean volumes of the heart and the LAD were lower (p<0.05) in 3D-DIBH for volumes receiving 5% to 80% of the prescription dose for the heart and 5% for the LAD. Mean dose to the LAD and heart were lower in 3D-DIBH (p≤0.01). Mean volumes of the total lung were lower in FB-IMRT for dose levels 20% to 75% (p<0.05), but mean dose was not different. Mean volumes of the right breast were not different for any dose; however, mean dose was lower for 3D-DIBH (p = 0.04). 3D-DIBH is an alternative approach to FB-IMRT that provides a clinically equivalent treatment for patients with left-sided breast cancer while sparing organs at risk with increased ease of implementation.« less

Wellens' syndrome and other electrocardiographic changes in a patient with a left anterior descending artery subocclusion associated with a left main coronary artery subocclusion.

PubMed

Patanè, Salvatore; Marte, Filippo

2011-09-01

Changing axis deviation has been reported also during atrial fibrillation or atrial flutter. Changing axis deviation has been also reported during acute myocardial infarction associated with atrial fibrillation too or at the end of atrial fibrillation during acute myocardial infarction. Patients with unstable angina have a higher incidence of left main coronary artery (LMCA) and proximal left anterior descending (LAD) coronary artery disease compared to patients with stable angina pectoris. In 1982, Wellens and colleagues described two electrocardiographic patterns that were predictive of critical narrowing of the proximal LAD artery, and were subsequently termed Wellens' syndrome. The criteria were: a) prior history of chest pain, b) little or no cardiac enzyme elevation, c) no pathologic precordial ST segment elevation, d) no loss of precordial R waves, and e) biphasic T waves in leads V2 and V3, or asymmetric, often deeply inverted T waves in leads V2 and V3. The ECG changes are best recognized outside the episode of anginal pain. Lead aVR and lead v1 ST segment elevation, during chest pain, has been reported in patients with LMCA disease with ST segment depression in leads V3, V4 and V5 (with maximal depression in V4).We present a case of changing axis deviation in a 37-year-old Italian man with a LAD coronary artery subocclusion associated with a LMCA subocclusion. This case focuses attention on the importance of the recognition of the patterns suspected for LAD coronary artery disease or for LMCA disease. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Chinese patent medicine Xin-Ke-Shu inhibits Ca2+ overload and dysfunction of fatty acid β-oxidation in rats with myocardial infarction induced by LAD ligation.

PubMed

Yang, Yong; Jia, Hongmei; Yu, Meng; Zhou, Chao; Sun, Lili; Zhao, Yang; Zhang, Hongwu; Zou, Zhongmei

2018-03-15

Myocardial infarction (MI) occurs during a sustained insufficient blood supply to the heart, eventually leading to myocardial necrosis. Xin-Ke-Shu tablet (XKS) is a prescription herbal compound and a patented medicine extensively used in the clinical treatment of coronary heart disease (CHD). To understand the molecular mechanism of the XKS action against MI in detail, it is necessary to investigate the altered metabolome and related pathways coincident with clinical features. In this study, tissue-targeted metabonomics based on ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) were developed to explore the metabolic changes associated with XKS treatment in the heart tissue of rats with MI induced by a left anterior descending coronary artery ligation (LAD). The metabolic disorder induced by LAD was alleviated after low-dose XKS (LD) and intermediate-dose XKS (MD) treatment. XKS modulated six perturbed metabolic pathways. Among them, inhibition of Ca 2+ overload and dysfunction of fatty acid β-oxidation-related metabolic pathways likely underlie the therapeutic effects of XKS against MI. In agreement with its observed effect on metabolite perturbation, XKS reversed the over-expression of the four key proteins, long-chain acyl-CoA synthetase 1 (ACSL1), carnitine palmitoyl transferase-1 (CPT1B), calcium/calmodulin-dependent kinase II (CaMKII), and phospholipase A2IIA (PLA2IIA). Both metabolite and protein changes suggested that XKS exerts its therapeutic effect on metabolic perturbations in LAD-induced MI mainly by inhibiting the Ca 2+ overload and fatty acid β-oxidation dysfunction. Copyright © 2018 Elsevier B.V. All rights reserved.

Characteristics of stroke mechanisms in patients with medullary infarction.

PubMed

Lee, M J; Park, Y G; Kim, S J; Lee, J J; Bang, O Y; Kim, J S

2012-11-01

Few studies have focused on the mechanisms underlying medullary infarctions. Our aim in this study was to investigate stroke mechanisms in patients with medullary infarctions and to determine the clinical, radiological and laboratory characteristics of these patients with different underlying stroke etiologies. Consecutive patients with medullary infarction were analysed. Stroke mechanisms were classified as large artery disease (LAD), cardiogenic embolism (CE), small vessel disease (SVD), arterial dissection or undetermined etiology. Clinical, radiological and laboratory factors were analysed according to the location of the lesion and stroke mechanisms. A total of 77 patients were enrolled in this study. Amongst them, 53 (68.8%) patients had lateral medullary infarction (LMI), 22 (28.6%) had medial medullary infarction (MMI), and the remaining 2 (2.6%) had hemimedullary infarction. In both LMI and MMI patients, LAD was the most frequently encountered stroke mechanism. Arterial dissection was the second most common cause followed by SVD and CE in patients with LMI, whereas SVD was more frequently observed (P < 0.001) and dissection and CE were less prevalent (P < 0.001 and P = 0.024, respectively) in MMI than in LMI. Regarding differences amongst stroke etiologies, patients with dissection were younger and had a significantly lower incidence of metabolic syndrome (P = 0.002 and P = 0.009, respectively) than patients with LAD and SVD. Patients in the LAD (19/34, 60%) and dissection groups (12/14, 75%) had abnormal perfusion-weighted MRI (PWI) findings, whereas all patients with SVD (9/9) had normal PWI findings (P < 0.001). Stroke mechanisms in medullary infarction differ between LMI and MMI. Clinical and radiological characteristics, especially PWI features, are helpful in discriminating the etiologies of stroke in these patients. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

Atorvastatin Improves Ventricular Remodeling after Myocardial Infarction by Interfering with Collagen Metabolism

PubMed Central

Reichert, Karla; Pereira do Carmo, Helison Rafael; Galluce Torina, Anali; Diógenes de Carvalho, Daniela; Carvalho Sposito, Andrei; de Souza Vilarinho, Karlos Alexandre; da Mota Silveira-Filho, Lindemberg; Martins de Oliveira, Pedro Paulo

2016-01-01

Purpose Therapeutic strategies that modulate ventricular remodeling can be useful after acute myocardial infarction (MI). In particular, statins may exert effects on molecular pathways involved in collagen metabolism. The aim of this study was to determine whether treatment with atorvastatin for 4 weeks would lead to changes in collagen metabolism and ventricular remodeling in a rat model of MI. Methods Male Wistar rats were used in this study. MI was induced in rats by ligation of the left anterior descending coronary artery (LAD). Animals were randomized into three groups, according to treatment: sham surgery without LAD ligation (sham group, n = 14), LAD ligation followed by 10mg atorvastatin/kg/day for 4 weeks (atorvastatin group, n = 24), or LAD ligation followed by saline solution for 4 weeks (control group, n = 27). After 4 weeks, hemodynamic characteristics were obtained by a pressure-volume catheter. Hearts were removed, and the left ventricles were subjected to histologic analysis of the extents of fibrosis and collagen deposition, as well as the myocyte cross-sectional area. Expression levels of mediators involved in collagen metabolism and inflammation were also assessed. Results End-diastolic volume, fibrotic content, and myocyte cross-sectional area were significantly reduced in the atorvastatin compared to the control group. Atorvastatin modulated expression levels of proteins related to collagen metabolism, including MMP1, TIMP1, COL I, PCPE, and SPARC, in remote infarct regions. Atorvastatin had anti-inflammatory effects, as indicated by lower expression levels of TLR4, IL-1, and NF-kB p50. Conclusion Treatment with atorvastatin for 4 weeks was able to attenuate ventricular dysfunction, fibrosis, and left ventricular hypertrophy after MI in rats, perhaps in part through effects on collagen metabolism and inflammation. Atorvastatin may be useful for limiting ventricular remodeling after myocardial ischemic events. PMID:27880844

Comparative gene expression analysis between coronary arteries and internal mammary arteries identifies a role for the TES gene in endothelial cell functions relevant to coronary artery disease.

PubMed

Archacki, Stephen R; Angheloiu, George; Moravec, Christine S; Liu, Hui; Topol, Eric J; Wang, Qing Kenneth

2012-03-15

Coronary artery disease (CAD) is the leading cause of death worldwide. It has been established that internal mammary arteries (IMA) are resistant to the development of atherosclerosis, whereas left anterior descending (LAD) coronary arteries are athero-prone. The contrasting properties of these two arteries provide an innovative strategy to identify the genes that play important roles in the development of atherosclerosis. We carried out microarray analysis to identify genes differentially expressed between IMA and LAD. Twenty-nine genes showed significant differences in their expression levels between IMA and LAD, which included the TES gene encoding Testin. The role of TES in the cardiovascular system is unknown. Here we show that TES is involved in endothelial cell (EC) functions relevant to atherosclerosis. Western blot analysis showed higher TES expression in IMA than in LAD. Reverse transcription polymerase chain reaction and western blot analyses showed that TES was consistently and markedly down-regulated by more than 6-fold at both mRNA and protein levels in patients with CAD compared with controls without CAD (P= 0.000049). The data suggest that reduced TES expression is associated with the development of CAD. Knockdown of TES expression by small-interfering RNA promoted oxidized-LDL-mediated monocyte adhesion to ECs, EC migration and the transendothelial migration of monocytes, while the over-expression of TES in ECs blunted these processes. These results demonstrate association between reduced TES expression and CAD, establish a novel role for TES in EC functions and raise the possibility that reduced TES expression increases susceptibility to the development of CAD.

Nuclear lamins are not required for lamina-associated domain organization in mouse embryonic stem cells.

PubMed

Amendola, Mario; van Steensel, Bas

2015-05-01

In mammals, the nuclear lamina interacts with hundreds of large genomic regions, termed lamina-associated domains (LADs) that are generally in a transcriptionally repressed state. Lamins form the major structural component of the lamina and have been reported to bind DNA and chromatin. Here, we systematically evaluate whether lamins are necessary for the LAD organization in murine embryonic stem cells. Surprisingly, removal of essentially all lamins does not have any detectable effect on the genome-wide interaction pattern of chromatin with emerin, a marker of the inner nuclear membrane. This suggests that other components of the lamina mediate these interactions. © 2015 The Authors.

[Linear IgA disease with ocular involvement associated with ulcerative colitis].

PubMed

Klein, A; Wenzel, S M; Messmer, E M; Landthaler, M; Vogt, T

2010-01-01

The association of linear IgA disease (LAD), ulcerative colitis and scarring ocular involvement is very rare and represents a considerable therapeutic challenge. We report a 48-year-old male diagnosed with ulcerative colitis in 1995, who received long-term methylprednisolone therapy. Later, he developed ocular inflammation with conjunctival scarring and synechiae formation as well as episodes of vesicles. Although azathioprine was added to his regimen, the disease was not controlled. After the diagnosis of LAD was established, dapsone was added. With this therapy, the ocular inflammation decreased significantly and the methylprednisolone dose could be successfully tapered slowly without reappearance of vesicles.

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

Lathers, C.M.; Spivey, W.H.; Levin, R.M.

The effect of metoprolol (M) on beta receptor density (BRD) was examined. M (5 mg/kg, p.o., b.i.d.) was given for 2 and 8 wks prior to CO of the left anterior descending artery (LAD) at its origin. BRD, determined by binding of /sup 3/H-dihydroalprenol, was examined in the myocardium (LA = left atrium, RA = right atrium, LV1 = proximal LAD distribution, LV = 2 distal LAD distribution, LV3 = posterior left ventricle, RV = right ventricle, and S = septum. A 2 factor ANOVA followed by simple effect and Newman-Keuls post hoc tests revealed that M produced no effectmore » in BRD in LA, RA, LV2, or S. M increased BRD in LV1, LV3, and RV after 2 wk when compared to no M. In addition, BRD in LV3 and RV were also greater at 2 wk than after 8 wk M. The data indicate that there are regional differences in the beta adrenergic receptor densities among the areas of the heart and within the left ventricle. Chronic dosing with M produced increased BRD in only some of the areas of the heart. These differences may be related to functional differences in the various areas of the heart after CO.« less

Gene expression in Listeria monocytogenes exposed to sublethal concentration of benzalkonium chloride.

PubMed

Tamburro, Manuela; Ripabelli, Giancarlo; Vitullo, Monia; Dallman, Timothy James; Pontello, Mirella; Amar, Corinne Francoise Laurence; Sammarco, Michela Lucia

2015-06-01

In this study, tolerance at sublethal concentration of benzalkonium chloride and transcription levels of mdrL, ladR, lde, sigB and bcrABC genes in Listeria monocytogenes strains were evaluated. Viable cells reduction occurred in 45% of strains and clinical isolates showed lower sensitivity than isolates from foods. An increased transcription of an efflux system encoding gene was found in 60% of strains, and simultaneous mdrL overexpression and ladR underexpression occurred in 30% of isolates. A significant association between reduced benzalkonium chloride activity and both mdrL and sigB overexpression was observed; sigB expression also correlated with both mdrL and ladR genes. The bcrABC gene was only found in six strains, all isolated from foods and sensitive to benzalkonium chloride, and in four strains an underexpression was observed. Disinfection at sublethal concentration was less effective in clinical isolates, and mdrL and sigB expression was significantly affected by disinfection. Further insights are needed to understand the adaptation to benzalkonium chloride and to evaluate whether changes in gene expression could affect the L. monocytogenes virulence traits and persistence in the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Steel reinforced composite silicone membranes and its integration to microfluidic oxygenators for high performance gas exchange.

PubMed

Matharoo, Harpreet; Dabaghi, Mohammadhossein; Rochow, Niels; Fusch, Gerhard; Saraei, Neda; Tauhiduzzaman, Mohammed; Veldhuis, Stephen; Brash, John; Fusch, Christoph; Selvaganapathy, P Ravi

2018-01-01

Respiratory distress syndrome (RDS) is one of the main causes of fatality in newborn infants, particularly in neonates with low birth-weight. Commercial extracorporeal oxygenators have been used for low-birth-weight neonates in neonatal intensive care units. However, these oxygenators require high blood volumes to prime. In the last decade, microfluidics oxygenators using enriched oxygen have been developed for this purpose. Some of these oxygenators use thin polydimethylsiloxane (PDMS) membranes to facilitate gas exchange between the blood flowing in the microchannels and the ambient air outside. However, PDMS is elastic and the thin membranes exhibit significant deformation and delamination under pressure which alters the architecture of the devices causing poor oxygenation or device failure. Therefore, an alternate membrane with high stability, low deformation under pressure, and high gas exchange was desired. In this paper, we present a novel composite membrane consisting of an ultra-thin stainless-steel mesh embedded in PDMS, designed specifically for a microfluidic single oxygenator unit (SOU). In comparison to homogeneous PDMS membranes, this composite membrane demonstrated high stability, low deformation under pressure, and high gas exchange. In addition, a new design for oxygenator with sloping profile and tapered inlet configuration has been introduced to achieve the same gas exchange at lower pressure drops. SOUs were tested by bovine blood to evaluate gas exchange properties. Among all tested SOUs, the flat design SOU with composite membrane has the highest oxygen exchange of 40.32 ml/min m 2 . The superior performance of the new device with composite membrane was demonstrated by constructing a lung assist device (LAD) with a low priming volume of 10 ml. The LAD was achieved by the oxygen uptake of 0.48-0.90 ml/min and the CO 2 release of 1.05-2.27 ml/min at blood flow rates ranging between 8 and 48 ml/min. This LAD was shown to increase the oxygen saturation level by 25% at the low pressure drop of 29 mm Hg. Finally, a piglet was used to test the gas exchange capacity of the LAD in vivo . The animal experiment results were in accordance with in-vitro results, which shows that the LAD is capable of providing sufficient gas exchange at a blood flow rate of ∼24 ml/min.

Dependence of Coronary 3-Dimensional Dose Maps on Coronary Topologies and Beam Set in Breast Radiation Therapy: A Study Based on CT Angiographies

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

Moignier, Alexandra, E-mail: alexandra.moignier@gmail.com; Broggio, David; Derreumaux, Sylvie

2014-05-01

Purpose: In left-side breast radiation therapy (RT), doses to the left main (LM) and left anterior descending (LAD) coronary arteries are usually assessed after delineation by prior anatomic knowledge on the treatment planning computed tomography (CT) scan. In this study, dose sensitivity due to interindividual coronary topology variation was assessed, and hot spots were located. Methods and Materials: Twenty-two detailed heart models, created from heart computed tomography angiographies, were fitted into a single representative female thorax. Two breast RT protocols were then simulated into a treatment planning system: the first protocol comprised tangential and tumoral bed beams (TGs{sub T}B) atmore » 50 + 16 Gy, the second protocol added internal mammary chain beams at 50 Gy to TGs{sub T}B (TGs{sub T}B{sub I}MC). For the heart, the LAD, and the LM, several dose indicators were calculated: dose-volume histograms, mean dose (D{sub mean}), minimal dose received by the most irradiated 2% of the volume (D{sub 2%}), and 3-dimensional (3D) dose maps. Variations of these indicators with anatomies were studied. Results: For the LM, the intermodel dispersion of D{sub mean} and D{sub 2%} was 10% and 11%, respectively, with TGs{sub T}B and 40% and 80%, respectively, with TGs{sub T}B{sub I}MC. For the LAD, these dispersions were 19% (D{sub mean}) and 49% (D{sub 2%}) with TGs{sub T}B and 35% (D{sub mean}) and 76% (D{sub 2%}) with TGs{sub T}B{sub I}MC. The 3D dose maps revealed that the internal mammary chain beams induced hot spots between 20 and 30 Gy on the LM and the proximal LAD for some coronary topologies. Without IMC beams, hot spots between 5 and 26 Gy are located on the middle and distal LAD. Conclusions: Coronary dose distributions with hot spot location and dose level can change significantly depending on coronary topology, as highlighted by 3D coronary dose maps. In clinical practice, coronary imaging may be required for a relevant coronary dose assessment, especially in cases of internal mammary chain irradiation.« less

Assessment of myocardial viability using 123I-labeled iodophenylpentadecanoic acid at sustained low flow or after acute infarction and reperfusion.

PubMed

Yang, J Y; Ruiz, M; Calnon, D A; Watson, D D; Beller, G A; Glover, D K

1999-05-01

123I-labeled iodophenylpentadecanoic acid (IPPA) is a synthetic fatty acid that may be useful for determination of myocardial viability. We investigated the uptake and clearance kinetics of this tracer in canine models of ischemia and infarction. In protocol 1, 185 MBq (5 mCi) 123I-IPPA were injected intravenously in 19 dogs with 50% left anterior descending artery (LAD) flow reduction. In 9 dogs, 201TI was coinjected. In protocol 2, 5 dogs underwent LAD occlusion for 3 h, and 123I-IPPA was injected 60 min after reperfusion. All dogs had flow measured by microspheres, regional systolic thickening by ultrasonic crystals and measurements of postmortem risk area and infarct size. Tracer activities were quantified by gamma well counting and by serial imaging. In protocol 1 dogs with sustained low flow (50% +/- 4%) and absence of systolic thickening (-3.2% +/- 1%), 123I-IPPA defect magnitude (LAD/left circumflex artery [LCX] count ratios) decreased from 0.65 +/- 0.02 to 0.74 +/- 0.02 at 30 min and to 0.84 +/- 0.03 at 2 h (P < 0.01), indicative of rest redistribution. Final transmural 123I-IPPA LAD/LCX activity ratio (0.99 +/- 0.05) was significantly greater than the flow ratio (0.53 +/- 0.04) at injection, confirming complete rest redistribution. The final 123I-IPPA activity ratio was significantly greater than the 201TI ratio over the 2-h period (P < 0.01). In protocol 2 dogs that underwent 3 h of total LAD occlusion and reflow (infarct size = 51% +/- 13% of risk area), viability was overestimated with 123I-IPPA, because uptake averaged 64% of normal in the central necrotic region, where flow averaged < 10% of normal. These findings suggest that serial 123I-IPPA imaging may be useful for assessing myocardial viability under conditions of sustained low flow and myocardial asynergy, such as appears to exist in patients with chronic coronary artery disease and depressed left ventricular function. In contrast, 123I-IPPA given early after reperfusion following prolonged coronary occlusion overestimates the degree of viability and therefore may not provide useful information pertaining to the degree of myocardial salvage after reflow in the setting of acute myocardial infarction.

An experiment to evaluate liquid hydrogen storage in space

NASA Technical Reports Server (NTRS)

Eberhardt, R. N.; Fester, D. A.; Johns, W. A.; Marino, J. S.

1981-01-01

The design and verification of a Cryogenic Fluid Management Experiment for orbital operation on the Shuttle is described. The experiment will furnish engineering data to establish design criteria for storage and supply of cryogenic fluids, mainly hydrogen, for use in low gravity environments. The apparatus comprises an LAD (liquid acquisition device) and a TVS (thermodynamic vent system). The hydrogen will be either vented or forced out by injected helium and the flow rates will be monitored. The data will be compared with ground-based simulations to determine optimal flow rates for the pressurizing gas and the release of the cryogenic fluid. It is noted that tests on a one-g, one-third size LAD system are under way.

Congenital Anomaly of Single Dominant Right Coronary Artery with Hypoplastic Left Coronary Artery.

PubMed

Chuang, Cheng-Yen; Chen, Yen-Chou; Cheng, Ho-Shun; Hsieh, Ming-Hsiung

2015-11-01

With the popularization of new imaging technology, more people are deciding to undergo non-invasive studies such as multidetector computerized tomography (MDCT) before receiving coronary angiography. For this reason, coronary anomalies of coronary artery are being encountered more frequently. We here report a 68-year-old male presenting with typical angina. The MDCT images suggested chronic total occlusion of the left anterior descending (LAD) artery with collateral circulation from the right coronary artery (RCA). The patient's coronary angiography showed a congenital coronary anomaly with a single dominant RCA supplying the entire coronary circulation of the heart with both LAD and left circumflex artery hypoplasia. Angiography; Anomaly; Computerized tomography; Coronary artery.

Determinants of plasma NT-pro-BNP levels in patients with atrial fibrillation and preserved left ventricular ejection fraction.

PubMed

Letsas, Konstantinos P; Filippatos, Gerasimos S; Pappas, Loukas K; Mihas, Constantinos C; Markou, Virginia; Alexanian, Ioannis P; Efremidis, Michalis; Sideris, Antonios; Maisel, Alan S; Kardaras, Fotios

2009-02-01

The present study aimed to investigate the clinical and echocardiographic determinants of plasma NT-pro-BNP levels in patients with atrial fibrillation (AF) and preserved left ventricular ejection fraction (LVEF). NT-pro-BNP levels were measured in 45 patients with paroxysmal AF, 41 patients with permanent AF and 48 controls. NT-pro-BNP levels were found significantly elevated in patients with paroxysmal (215+/-815 pg/ml) and permanent AF (1,086+/-835 pg/ml) in relation to control population (86.3+/-77.9 pg/ml) (P<0.001). According to the univariate linear regression analysis, age, hypertension, beta-blocker use, left atrial diameter (LAD), LVEF and AF status (paroxysmal or permanent or both) were significantly associated with NT-pro-BNP levels (P<0.05). In multiple linear regression analysis, LVEF (B coefficient: -53.030; CI: -95.738 to -10.322; P: 0.015) and LAD (B coefficient: 285.858; CI: 23.731-547.986; P: 0.033) were significant and independent determinants of NT-pro-BNP levels. Plasma NT-pro-BNP levels were significantly higher in patients with paroxysmal and permanent AF compared to those with sinus rhythm in the setting of preserved left ventricular systolic function. LVEF and LAD were independent predictors of NT-pro-BNP levels.

CSF/serum albumin ratio in dementias: a cross-sectional study on 1861 patients.

PubMed

Skillbäck, Tobias; Delsing, Louise; Synnergren, Jane; Mattsson, Niklas; Janelidze, Shorena; Nägga, Katarina; Kilander, Lena; Hicks, Ryan; Wimo, Anders; Winblad, Bengt; Hansson, Oskar; Blennow, Kaj; Eriksdotter, Maria; Zetterberg, Henrik

2017-11-01

A connection between dementias and blood-brain barrier (BBB) dysfunction has been suggested, but previous studies have yielded conflicting results. We examined cerebrospinal fluid (CSF)/serum albumin ratio in a large cohort of patients diagnosed with Alzheimer's disease (AD, early onset [EAD, n = 130], late onset AD [LAD, n = 666]), vascular dementia (VaD, n = 255), mixed AD and VaD (MIX, n = 362), Lewy body dementia (DLB, n = 50), frontotemporal dementia (FTD, n = 56), Parkinson's disease dementia (PDD, n = 23), other dementias (other, n = 48), and dementia not otherwise specified (NOS, n = 271). We compared CSF/serum albumin ratio to 2 healthy control groups (n = 292, n = 20), between dementia diagnoses, and tested biomarker associations. Patients in DLB, LAD, VaD, MIX, other, and NOS groups had higher CSF/serum albumin ratio than controls. CSF/serum albumin ratio correlated with CSF neurofilament light in LAD, MIX, VaD, and other groups but not with AD biomarkers. Our data show that BBB leakage is common in dementias. The lack of association between CSF/serum albumin ratio and AD biomarkers suggests that BBB dysfunction is not inherent to AD but might represent concomitant cerebrovascular pathology. Copyright © 2017 Elsevier Inc. All rights reserved.

Longitudinal association of short-term, metronome-paced heart rate variability and echocardiographically assessed cardiac structure at a 4-year follow-up: results from the prospective, population-based CARLA cohort.

PubMed

Medenwald, Daniel; Swenne, Cees A; Frantz, Stefan; Nuding, Sebastian; Kors, Jan A; Pietzner, Diana; Tiller, Daniel; Greiser, Karin H; Kluttig, Alexander; Haerting, Johannes

2017-12-01

To assess the value of cardiac structure/function in predicting heart rate variability (HRV) and the possibly predictive value of HRV on cardiac parameters. Baseline and 4-year follow-up data from the population-based CARLA cohort were used (790 men, 646 women, aged 45-83 years at baseline and 50-87 years at follow-up). Echocardiographic and HRV recordings were performed at baseline and at follow-up. Linear regression models with a quadratic term were used. Crude and covariate adjusted estimates were calculated. Missing values were imputed by means of multiple imputation. Heart rate variability measures taken into account consisted of linear time and frequency domain [standard deviation of normal-to-normal intervals (SDNN), high-frequency power (HF), low-frequency power (LF), LF/HF ratio] and non-linear measures [detrended fluctuation analysis (DFA1), SD1, SD2, SD1/SD2 ratio]. Echocardiographic parameters considered were ventricular mass index, diastolic interventricular septum thickness, left ventricular diastolic dimension, left atrial dimension systolic (LADS), and ejection fraction (Teichholz). A negative quadratic relation between baseline LADS and change in SDNN and HF was observed. The maximum HF and SDNN change (an increase of roughly 0.02%) was predicted at LADS of 3.72 and 3.57 cm, respectively, while the majority of subjects experienced a decrease in HRV. There was no association between further echocardiographic parameters and change in HRV, and there was no evidence of a predictive value of HRV in the prediction of changes in cardiac structure. In the general population, LADS predicts 4-year alteration in SDNN and HF non-linearly. Because of the novelty of the result, analyses should be replicated in other populations. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions please email: journals.permissions@oup.com.

Coronary Flow Velocity Reserve during Dobutamine Stress Echocardiography

PubMed Central

de Abreu, José Sebastião; Lima, José Wellington Oliveira; Diógenes, Tereza Cristina Pinheiro; Siqueira, Jordana Magalhães; Pimentel, Nayara Lima; Gomes, Pedro Sabino; de Abreu, Marília Esther Benevides; Paes, José Nogueira

2014-01-01

Background A coronary flow velocity reserve (CFVR) ≥ 2 is adequate to infer a favorable prognosis or the absence of significant coronary artery disease. Objective To identify parameters which are relevant to obtain CFVR (adequate or inadequate) in the left anterior descending coronary artery (LAD) during dobutamine stress echocardiography (DSE). Methods 100 patients referred for detection of myocardial ischemia by DSE were evaluated; they were instructed to discontinue the use of β-blockers 72 hours prior to the test. CFVR was calculated as a ratio of the diastolic peak velocity (cm/s) (DPV) on DSE (DPV-DSE) to baseline DPV at rest (DPV-Rest). In group I, CFVR was < 2 and, in group II, CFVR was ≥ 2. The Fisher's exact test and Student's t test were used for the statistical analyses. P values < 0.05 were considered statistically significant. Results At rest, the time (in seconds) to obtain Doppler in LAD in groups I and II was not different (53±31 vs. 45±32; p=0.23). During DSE, LAD was recorded in 92 patients. Group I patients were older (65.9±9.3 vs. 61.2±10.8 years; p=0.04), had lower ejection fraction (61±10 vs. 66±6%; p=0.005), higher DPV-Rest (36.81±08 vs. 25.63 ± 06cm/s; p<0.0001) and lower CFVR (1.67 ± 0.24 vs. 2.53 ± 0.57; p<0.0001), but no difference was observed regarding DPVDSE (61.40±16 vs. 64.23±16cm/s; p=0.42). β-blocker discontinuation was associated with a 4-fold higher chance of a CFVR < 2 (OR= 4; 95% CI [1.171-13.63], p=0.027). Conclusion DPV-Rest was the main parameter to determine an adequate CFVR. β-blocker discontinuation was significantly associated with inadequate CFVR. The high feasibility and the time to record the LAD corroborate the use of this methodology. PMID:24676368

Hepatic Microwave Ablation Zone Size: Correlation with Total Energy, Net Energy, and Manufacturer-Provided Chart Predictions.

PubMed

Shyn, Paul B; Bird, Jeffery R; Koch, R Marie; Tatli, Servet; Levesque, Vincent M; Catalano, Paul J; Silverman, Stuart G

2016-09-01

To determine whether total energy (TE) reaching the microwave (MW) applicator or net energy (NE) exiting the applicator (after correcting for reflectivity) correlates better with hepatic MW ablation zone dimensions than manufacturer-provided chart predictions. Single-applicator, nonoverlapping ablations of 93 liver tumors (0.7-5.9 cm) were performed in 52 adult patients. TE and NE were recorded for each ablation. Long axis diameter (LAD), short axis diameter (SAD), and volume (V) of each ablation zone were measured on magnetic resonance imaging or computed tomography after the procedure and retrospectively compared with TE; NE; and manufacturer-provided chart predictions of LAD, SAD, and V using correlation and regression analyses. For treated tumors, mean (± SD) TE and NE were 49.8 kJ (± 22.7) and 36.4 kJ (± 19.4). Mean LAD, SAD, and V were 5.8 cm (± 1.3), 3.7 cm (± 0.8), and 44.1 cm(3) (± 25.4). Correlation coefficients (95% confidence interval) with LAD, SAD, and V were 0.46 (0.28, 0.61), 0.52 (0.36, 0.66), and 0.52 (0.36, 0.66) for TE; 0.42 (0.24, 0.58), 0.55 (0.39, 0.68), and 0.53 (0.36, 0.66) for NE; and 0.51 (0.34, 0.65), 0.63 (0.49, 0.74), and 0.60 (0.45, 0.73) for chart predictions. Using regression analysis and controlling for TE, SAD was 0.34 cm larger in patients with cirrhosis than in patients without cirrhosis. Correcting for reflectivity did not substantially improve correlation of energy values with MW ablation zone size parameters and did not outperform manufacturer-provided chart predictions. Correlations were moderate and variable using all methods. The results suggest a disproportionate influence of tissue factors on MW ablation results. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

The small-molecule fast skeletal troponin activator, CK-2127107, improves exercise tolerance in a rat model of heart failure.

PubMed

Hwee, Darren T; Kennedy, Adam R; Hartman, James J; Ryans, Julie; Durham, Nickie; Malik, Fady I; Jasper, Jeffrey R

2015-04-01

Heart failure-mediated skeletal myopathy, which is characterized by muscle atrophy and muscle metabolism dysfunction, often manifests as dyspnea and limb muscle fatigue. We have previously demonstrated that increasing Ca(2+) sensitivity of the sarcomere by a small-molecule fast skeletal troponin activator improves skeletal muscle force and exercise performance in healthy rats and models of neuromuscular disease. The objective of this study was to investigate the effect of a novel fast skeletal troponin activator, CK-2127107 (2-aminoalkyl-5-N-heteroarylpyrimidine), on skeletal muscle function and exercise performance in rats exhibiting heart failure-mediated skeletal myopathy. Rats underwent a left anterior descending coronary artery ligation, resulting in myocardial infarction and a progressive decline in cardiac function [left anterior descending coronary artery heart failure (LAD-HF)]. Compared with sham-operated control rats, LAD-HF rat hindlimb and diaphragm muscles exhibited significant muscle atrophy. Fatigability was increased during repeated in situ isokinetic plantar flexor muscle contractions. CK-2127107 produced a leftward shift in the force-Ca(2+) relationship of skinned, single diaphragm, and extensor digitorum longus fibers. Exercise performance, which was assessed by rotarod running, was lower in vehicle-treated LAD-HF rats than in sham controls (116 ± 22 versus 193 ± 31 seconds, respectively; mean ± S.E.M.; P = 0.04). In the LAD-HF rats, a single oral dose of CK-2127107 (10 mg/kg p.o.) increased running time compared with vehicle treatment (283 ± 47 versus 116 ± 22 seconds; P = 0.0004). In summary, CK-2127107 substantially increases exercise performance in this heart failure model, suggesting that modulation of skeletal muscle function by a fast skeletal troponin activator may be a useful therapeutic in heart failure-associated exercise intolerance. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Transit Time Flowmetry in Coronary Artery Bypass Grafting-experience at Queen Alia Heart Institute, Jordan

PubMed Central

Harahsheh, Basel

2012-01-01

Objectives To assess the results of transit time flowmetry (TTF) on a consecutive group of coronary artery bypass grafting (CABG) patients at Queen Alia Heart Institute. Methods Intraoperative flow measurements of a consecutive group of 436 CABG patients. The flow pattern for each coronary artery system was assessed including mean flows, pulsatility index (PI) and the need for revision. Results A total of 1394 grafts in 436 patients were assessed (3.2 grafts per patient), wherein 100 grafts showed inadequate flowmetry results (7.2%); most of which were in the circumflex and right coronary artery systems with a percentage of 9.4% and the least in the LAD system with a percentage of 4.4%. The mean flow of grafts to the LAD system was 33.4±5.3 mL/min with a PI of 2.4±0.4; while the mean for grafts to the circumflex artery system was 35.1±7.2 mL/min with a PI of 3.5±0.7. The mean for the right coronary artery was 38.4±5.9 mL/min with a PI of 2.6±0.6. Revisions occurred in five patients (1.1%). Suboptimal grafts to the LAD system exhibited a flow of 14.1±7.4 mL/min with a PI of 6.9±1.7. While for the circumflex system a flow of 5.5±3.6 mL/min was reported with a PI of 10.4±7.8; and for the right coronary system a flow of 7.2±5.3 mL/min with a PI of 9.1±5.7 was reported. Conclusion Grafts to the LAD system showed the best flowmetry results compared to grafts to the circumflex and right coronary systems. A proportion of poor grafts were revised. PMID:23226818

Coronary flow velocity reserve by echocardiography: feasibility, reproducibility and agreement with PET in overweight and obese patients with stable and revascularized coronary artery disease.

PubMed

Olsen, Rasmus Huan; Pedersen, Lene Rørholm; Snoer, Martin; Christensen, Thomas Emil; Ghotbi, Adam Ali; Hasbak, Philip; Kjaer, Andreas; Haugaard, Steen B; Prescott, Eva

2016-06-07

Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography of the LAD is used to assess microvascular function but validation studies in clinical settings are lacking. We aimed to assess feasibility, reproducibility and agreement with myocardial flow reserve (MFR) measured by PET in overweight and obese patients. Participants with revascularized coronary artery disease were examined by CFVR. Subgroups were examined by repeated CFVR (reproducibility) or Rubidium-82-PET (agreement). To account for time variation, results were computed for scans performed within a week (1-week) and for all scans regardless of time gap (total) and to account for scar tissue for patients with and without previous myocardial infarction (MI). Eighty-six patients with median BMI 30.9 (IQR 29.4-32.9) kg × m(-2) and CFVR 2.29 (1.90-2.63) were included. CFVR was feasible in 83 (97 %) using a contrast agent in 14 %. For reproducibility overall (n = 21) limits of agreement (LOA) were (-0.75;0.71), within-subjects coefficient of variation (CV) 11 %, and reliability 0.84. For reproducibility within 1-week (n = 13) LOA were (-0.33;0.25), within-subjects CV 5 %, and reliability 0.97. Agreement with MFR of the LAD territory (n = 35) was without significant bias and overall LOA were (-1.40;1.46). Agreement was best for examinations performed within 1-week of participants without MI of the LAD-territory (n = 12); LOA = (-0.68;0.88). CFVR was highly feasible with a good reproducibility on par with other contemporary measures applied in cardiology. Agreement with MFR was acceptable, though discrepancy related to prior MI has to be considered. CFVR of LAD is a valid tool in overweight and obese patients.

Effect of beam hardening on transmural myocardial perfusion quantification in myocardial CT imaging

NASA Astrophysics Data System (ADS)

Fahmi, Rachid; Eck, Brendan L.; Levi, Jacob; Fares, Anas; Wu, Hao; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

2016-03-01

The detection of subendocardial ischemia exhibiting an abnormal transmural perfusion gradient (TPG) may help identify ischemic conditions due to micro-vascular dysfunction. We evaluated the effect of beam hardening (BH) artifacts on TPG quantification using myocardial CT perfusion (CTP). We used a prototype spectral detector CT scanner (Philips Healthcare) to acquire dynamic myocardial CTP scans in a porcine ischemia model with partial occlusion of the left anterior descending (LAD) coronary artery guided by pressure wire-derived fractional flow reserve (FFR) measurements. Conventional 120 kVp and 70 keV projection-based mono-energetic images were reconstructed from the same projection data and used to compute myocardial blood flow (MBF) using the Johnson-Wilson model. Under moderate LAD occlusion (FFR~0.7), we used three 5 mm short axis slices and divided the myocardium into three LAD segments and three remote segments. For each slice and each segment, we characterized TPG as the mean "endo-to-epi" transmural flow ratio (TFR). BH-induced hypoenhancement on the ischemic anterior wall at 120 kVp resulted in significantly lower mean TFR value as compared to the 70 keV TFR value (0.29+/-0.01 vs. 0.55+/-0.01 p<1e-05). No significant difference was measured between 120 kVp and 70 keV mean TFR values on segments moderately affected or unaffected by BH. In the entire ischemic LAD territory, 120 kVp mean endocardial flow was significantly reduced as compared to mean epicardial flow (15.80+/-10.98 vs. 40.85+/-23.44 ml/min/100g; p<1e-04). At 70 keV, BH was effectively minimized resulting in mean endocardial MBF of 40.85+/-15.3407 ml/min/100g vs. 74.09+/-5.07 ml/min/100g (p=0.0054) in the epicardium. We also found that BH artifact in the conventional 120 kVp images resulted in falsely reduced MBF measurements even under non-ischemic conditions.

Leukocyte Adhesion Deficiency (LAD)

MedlinePlus

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Analysis of Screen Channel LAD Bubble Point Tests in Liquid Methane at Elevated Temperature

NASA Technical Reports Server (NTRS)

Hartwig, Jason; McQuillen, John

2012-01-01

This paper examines the effect of varying the liquid temperature and pressure on the bubble point pressure for screen channel Liquid Acquisition Devices in cryogenic liquid methane using gaseous helium across a wide range of elevated pressures and temperatures. Testing of a 325 x 2300 Dutch Twill screen sample was conducted in the Cryogenic Components Lab 7 facility at the NASA Glenn Research Center in Cleveland, Ohio. Test conditions ranged from 105 to 160K and 0.0965 - 1.78 MPa. Bubble point is shown to be a strong function of the liquid temperature and a weak function of the amount of subcooling at the LAD screen. The model predicts well for saturated liquid but under predicts the subcooled data.

Quantitative Assessment of Regional Wall Motion Abnormalities Using Dual-Energy Digital Subtraction Intravenous Ventriculography

NASA Astrophysics Data System (ADS)

McCollough, Cynthia H.

Healthy portions of the left ventricle (LV) can often compensate for regional dysfunction, thereby masking regional disease when global indices of LV function are employed. Thus, quantitation of regional function provides a more useful method of assessing LV function, especially in diseases that have regional effects such as coronary artery disease. This dissertation studied the ability of a phase -matched dual-energy digital subtraction angiography (DE -DSA) technique to quantitate changes in regional LV systolic volume. The potential benefits and a theoretical description of the DE imaging technique are detailed. A correlated noise reduction algorithm is also presented which raises the signal-to-noise ratio of DE images by a factor of 2 -4. Ten open-chest dogs were instrumented with transmural ultrasonic crystals to assess regional LV function in terms of systolic normalized-wall-thickening rate (NWTR) and percent-systolic-thickening (PST). A pneumatic occluder was placed on the left-anterior-descending (LAD) coronary artery to temporarily reduce myocardial blood flow, thereby changing regional LV function in the LAD bed. DE-DSA intravenous left ventriculograms were obtained at control and four levels of graded myocardial ischemia, as determined by reductions in PST. Phase-matched images displaying changes in systolic contractile function were created by subtracting an end-systolic (ES) control image from ES images acquired at each level of myocardial ischemia. The resulting wall-motion difference signal (WMD), which represents a change in regional systolic volume between the control and ischemic states, was quantitated by videodensitometry and compared with changes in NWTR and PST. Regression analysis of 56 data points from 10 animals shows a linear relationship between WMD and both NWTR and PST: WMD = -2.46 NWTR + 13.9, r = 0.64, p < 0.001; WMD = -2.11 PST + 18.4, r = 0.54, p < 0.001. Thus, changes in regional ES LV volume between rest and ischemic states, as measured using the described imaging technique, appear linearly related to changes in wall-thickening, as measured using transmural ultrasonic crystals. This type of image analysis may prove useful in a variety of clinical and research applications and further investigation is proposed.

Anomalous Coronary Arteries and Myocardial Bridges: Risk Stratification in Children Using Novel Cardiac Catheterization Techniques.

PubMed

Agrawal, Hitesh; Molossi, Silvana; Alam, Mahboob; Sexson-Tejtel, S Kristen; Mery, Carlos M; McKenzie, E Dean; Fraser, Charles D; Qureshi, Athar M

2017-03-01

The evaluation of the vast majority of children with anomalous aortic origin of a coronary artery (AAOCA) and/or myocardial bridges is performed with non-invasive testing. However, a subset of these patients may benefit from invasive testing for risk stratification. All patients included in the Coronary Anomalies Program (CAP) at Texas Children's Hospital who underwent cardiac catheterization were included. Techniques included selective coronary angiograms (SCA), intravascular ultrasound (IVUS), and fractional flow reserve (FFR) measurements with provocative testing using adenosine and/or dobutamine infusions. Out of the 131 patients followed by the CAP between 12/12-4/16, 8 (6%) patients underwent 9 cath investigations at median age 13.1 (2.6-18.7) years and median weight 49.5 (11.4-142.7) kg. Six patients presented with cardiac signs/symptoms. Four patients had myocardial bridges of the left anterior descending (LAD) coronary artery, 2 patients had isolated AAOCA, and 2 patients had an anomalous left coronary artery (LCA) with an intramyocardial course of the LAD. SCA was performed in all patients. FFR was positive in 4/6 patients: IVUS showed >70% intraluminal narrowing in 3/5 patients. One patient had hemodynamic instability that reversed with catheter removal from the coronary ostium. Based on the catheterization data obtained, findings were reassuring in three patients, surgery was performed in three patients, and two patients are being medically managed/restricted from competitive sports. In our small cohort of patients, we demonstrated that IVUS and FFR can safely be performed in children and may help to risk stratify some patients with AAOCA and myocardial bridges.

Upregulation of Mas-related G Protein coupled receptor X2 in asthmatic lung mast cells and its activation by the novel neuropeptide hemokinin-1.

PubMed

Manorak, Wichayapha; Idahosa, Chizobam; Gupta, Kshitij; Roy, Saptarshi; Panettieri, Reynold; Ali, Hydar

2018-01-03

Hemokinin-1 (HK-1) is a novel neuropeptide produced by human bronchial cells and macrophages and causes contraction of human bronchi ex vivo. It is also generated by antigen/IgE-activated murine mast cells (MCs) and contributes to experimental chronic allergic airway inflammation via the activation of the neurokinin receptor-1 (NK-1R) expressed on murine MCs. We found elevated MC numbers in the lungs of individuals who died from asthma (asthma) when compared to lungs of individuals who died from other causes (non-asthma). Mas-related G Protein coupled receptor X2 (MRGPRX2) is a novel G-protein coupled receptor (GPCR) that is expressed predominantly on human MCs. We detected low level of MRGPRX2 in non-asthma lung MCs but its expression was significantly upregulated in asthma lung MCs. HK-1 caused degranulation in a human MC line (LAD2) and RBL-2H3 cells stably expressing MRGPRX2 and this response was resistant to inhibition by an NK-1R antagonist. However, knockdown of MRGPRX2 in LAD2 cells resulted in substantial inhibition of HK-1-induced degranulation. These findings suggest that while HK-1 contributes to the development of experimental asthma in mice via NK-1R on murine MCs the effect of this neuropeptide on human bronchoconstriction likely reflects the activation of MRGPRX2 on lung MCs. Thus, development of selective MRGPRX2 antagonists could serve as novel target for the modulation of asthma.

An enhanced model of land water and energy for global hydrologic and earth-system studies

USGS Publications Warehouse

Milly, Paul C.D.; Malyshev, Sergey L.; Shevliakova, Elena; Dunne, Krista A.; Findell, Kirsten L.; Gleeson, Tom; Liang, Zhi; Phillips, Peter; Stouffer, Ronald J.; Swenson, Sean

2014-01-01

LM3 is a new model of terrestrial water, energy, and carbon, intended for use in global hydrologic analyses and as a component of earth-system and physical-climate models. It is designed to improve upon the performance and to extend the scope of the predecessor Land Dynamics (LaD) and LM3V models by better quantifying the physical controls of climate and biogeochemistry and by relating more directly to components of the global water system that touch human concerns. LM3 includes multilayer representations of temperature, liquid water content, and ice content of both snowpack and macroporous soil–bedrock; topography-based description of saturated area and groundwater discharge; and transport of runoff to the ocean via a global river and lake network. Sensible heat transport by water mass is accounted throughout for a complete energy balance. Carbon and vegetation dynamics and biophysics are represented as in LM3V. In numerical experiments, LM3 avoids some of the limitations of the LaD model and provides qualitatively (though not always quantitatively) reasonable estimates, from a global perspective, of observed spatial and/or temporal variations of vegetation density, albedo, streamflow, water-table depth, permafrost, and lake levels. Amplitude and phase of annual cycle of total water storage are simulated well. Realism of modeled lake levels varies widely. The water table tends to be consistently too shallow in humid regions. Biophysical properties have an artificial stepwise spatial structure, and equilibrium vegetation is sensitive to initial conditions. Explicit resolution of thick (>100 m) unsaturated zones and permafrost is possible, but only at the cost of long (≫300 yr) model spinup times.

Real-time visualization and quantification of retrograde cardioplegia delivery using near infrared fluorescent imaging.

PubMed

Rangaraj, Aravind T; Ghanta, Ravi K; Umakanthan, Ramanan; Soltesz, Edward G; Laurence, Rita G; Fox, John; Cohn, Lawrence H; Bolman, R M; Frangioni, John V; Chen, Frederick Y

2008-01-01

Homogeneous delivery of cardioplegia is essential for myocardial protection during cardiac surgery. Presently, there exist no established methods to quantitatively assess cardioplegia distribution intraoperatively and determine when retrograde cardioplegia is required. In this study, we evaluate the feasibility of near infrared (NIR) imaging for real-time visualization of cardioplegia distribution in a porcine model. A portable, intraoperative, real-time NIR imaging system was utilized. NIR fluorescent cardioplegia solution was developed by incorporating indocyanine green (ICG) into crystalloid cardioplegia solution. Real-time NIR imaging was performed while the fluorescent cardioplegia solution was infused via the retrograde route in five ex vivo normal porcine hearts and in five ex vivo porcine hearts status post left anterior descending (LAD) coronary artery ligation. Horizontal cross-sections of the hearts were obtained at proximal, middle, and distal LAD levels. Videodensitometry was performed to quantify distribution of fluorophore content. The progressive distribution of cardioplegia was clearly visualized with NIR imaging. Complete visualization of retrograde distribution occurred within 4 minutes of infusion. Videodensitometry revealed retrograde cardioplegia, primarily distributed to the left ventricle (LV) and anterior septum. In hearts with LAD ligation, antegrade cardioplegia did not distribute to the anterior LV. This deficiency was compensated for with retrograde cardioplegia supplementation. Incorporation of ICG into cardioplegia allows real-time visualization of cardioplegia delivery via NIR imaging. This technology may prove useful in guiding intraoperative decisions pertaining to when retrograde cardioplegia is mandated.

LAD-C: A large area debris collector on the ISS

NASA Technical Reports Server (NTRS)

Liou, J.-C.; Giovane, F. J.; Corsaro, R. D.; Burchell, M. J.; Drolshagen, G.; Kawai, H.; Stansbery, E. G.; Tabata, M.; Westphal, A. J.; Yano, H.

2006-01-01

The Large Area Debris Collector (LAD-C) is a 10 sq m aerogel and acoustic sensor system under development by the U.S. Naval Research Laboratory (NRL) with main collaboration from the NASA Orbital Debris Program Office at Johnson Space Center, JAXA Institute of Space and Astronautical Science (ISAS), Chiba University (Japan), ESA Space Debris Office, University of California at Berkeley, and University of Kent at Canterbury (UK). The U.S. Department of Defense (DoD) Space Test Program (STP) has assumed the responsibility for having the system manifested and deployed on the International Space Station (ISS), and then having it retrieved and returned to Earth after one to two years. LAD-C will attempt to utilize the ISS as a scientific platform to characterize the near-Earth meteoroid and orbital debris environment in the size regime where little data exist. In addition to meteoroid and orbital debris sample return, the acoustic sensors will record impact time, location, signal strength, and acoustic waveform data of the largest collected samples. A good time-dependent meteoroid and orbital debris flux estimate can be derived. Analysis of the data will also enable potential source identification of some of the collected samples. This dynamical link can be combined with laboratory composition analysis of impact residuals extracted from aerogel to further our understanding of orbital debris population, and the sources of meteoroids, asteroids and comets.

Percutaneous treatment with drug-eluting stent vs bypass surgery in patients suffering from chronic stable angina with multivessel disease involving significant proximal stenosis in left anterior descending artery.

PubMed

Yan, Qiao; Changsheng, Ma; Shaoping, Nie; Xiaohui, Liu; Junping, Kang; Qiang, Lv; Xin, Du; Rong, Hu; Yin, Zhang; Changqi, Jia; Jiahui, Wu; Xinmin, Liu; Jianzeng, Dong; Fang, Chen; Yujie, Zhou; Shuzheng, Lv; Fangjiong, Huang; Chengxiong, Gu; Xuesi, Wu

2009-10-01

The aim of the present study was to compare the effects of drug-eluting stents (DES) and coronary artery bypass grafting (CABG) in patients suffering from chronic stable angina with multivessel disease, involving significant proximal stenosis in the left anterior descending artery (LAD). All consecutive patients suffering from chronic stable angina with multivessel disease involving significant proximal LAD stenosis underwent DES implantation (n=600) or CABG (n=709) at our institution. At 2 years, the unadjusted mortality was significantly lower in the DES group than in the CABG group (2.2% vs 5.2%, P=0.004), but the adjusted risk of death was similar (odds ratio (OR) 0.74, 95%CI 0.28-1.97, P=0.555). Furthermore, both the adjusted rate of nonfatal myocardial infarction and cerebrovascular events was also comparable. However, the unadjusted and adjusted risk of major adverse cardiac cerebrovascular events in the DES was significantly higher than in the CABG (13.3% vs 9.6%, OR 2.71, 95%CI 1.56-4.74, P<0.001), which is probably attributed to the higher subsequent revascularization rate after DES implantation. DES showed comparable long-term mortality for the treatment of multivessel disease involving significant proximal stenosis in LAD in comparison with CABG.

Subclinical Enteric Parasitic Infections and Growth Faltering in Infants in São Tomé, Africa: A Birth Cohort Study

PubMed Central

Garzón, Marisol; Seixas, Jorge; Papoila, Ana Luísa; Alves, Marta

2018-01-01

The associations between enteric pathogenic parasites and growth in infants in São Tomé were explored using a refined anthropometric approach to recognize early growth faltering. A birth cohort study was conducted with follow-up to 24 months of age. Microscopic examination for protozoa and soil-transmitted helminths was performed. Anthropometric assessments included: z-scores for weight-for-length (WLZ), length-for-age (LAZ), weight (WAVZ) and length velocities (LAVZ), length-for-age difference (LAD), and wasting and stunting risk (≤−1 SD). Generalized additive mixed effects regression models were used to explore the associations between anthropometric parameters and enteric parasitic infections and cofactors. A total of 475 infants were enrolled, and 282 completed the study. The great majority of infants were asymptomatic. Giardia lamblia was detected in 35.1% of infants in at least one stool sample, helminths in 30.4%, and Cryptosporidium spp. in 14.7%. Giardia lamblia and helminth infections were significantly associated with mean decreases of 0.10 in LAZ and 0.32 in LAD, and of 0.16 in LAZ and 0.48 in LAD, respectively. Cryptosporidium spp. infection was significantly associated with a mean decrease of 0.43 in WAVZ and 0.55 in LAVZ. The underestimated association between subclinical parasitic enteric infections and mild growth faltering in infants should be addressed in public health policies. PMID:29621166

Heterogeneity in Kv7 channel function in the cerebral and coronary circulation.

PubMed

Lee, Sewon; Yang, Yan; Tanner, Miles A; Li, Min; Hill, Michael A

2015-02-01

Kv7 channels are considered important regulators of vascular smooth muscle contractility. The present study aimed to examine the hypotheses that (i) Kv7 channels are present in mouse cerebral and coronary arteries and regulate vascular reactivity and (ii) regional differences exist in the activity of these channels. PCR confirmed that basilar, Circle of Willis and LAD arteries express predominantly Kv7.1 and 7.4. Western blot analysis, however, showed greater Kv7.4 protein levels in the cerebral vessels. Relaxation to the Kv7 channel activator, retigabine (1-50 μM) was significantly greater in the basilar artery compared to the LAD artery. Similarly, the Kv7 channel inhibitor, linopirdine (10 μM) caused a stronger contraction of the basilar artery. Furthermore, pre-incubation with linopirdine reduced forskolin (cAMP activator)-induced vasorelaxation in basilar while not altering forskolin-induced vasorelaxation of the LAD, suggesting that Kv7 channels play a more prominent role in the cerebral than in the coronary circulation. Consistent with the vessel data, whole cell Kv7 currents in cerebral VSMCs were potentiated by retigabine and inhibited by linopirdine, while these responses were blunted in coronary VSMCs. This study provides evidence that mouse Kv7 channels may contribute differently to regulating the functional properties of cerebral and coronary arteries. Such heterogeneity has important implications for developing novel therapeutics for cardiovascular dysfunction. © 2014 John Wiley & Sons Ltd.

Heterogeneity in Kv7 channel function in the Cerebral and Coronary Circulation

PubMed Central

Tanner, Miles A.; Li, Min; Hill, Michael A.

2014-01-01

Kv7 channels are considered important regulators of vascular smooth muscle contractility. The present study examined the hypotheses that 1. Kv7 channels are present in mouse cerebral and coronary arteries and regulate vascular reactivity, and 2. regional differences exist in the activity of these channels. PCR confirmed that basilar, Circle of Willis and left anterior descending (LAD) arteries express predominantly Kv7.1 and 7.4. Western blot analysis, however, showed greater Kv7.4 protein levels in the cerebral vessels. Relaxation to the Kv7 channel activator, retigabine (1-50μM) was significantly greater in basilar compared to LAD. Similarly, the Kv7 channel inhibitor, linopirdine (10μM) caused stronger contraction of the basilar artery. Furthermore, pre-incubation with linopirdine reduced forskolin (cAMP activator)-induced vasorelaxation in basilar while not altering forskolin-induced vasorelaxation of the LAD, suggesting that Kv7 channels play a more prominent role in the cerebral than coronary circulation. Consistent with the vessel data, whole cell Kv7 currents in cerebral VSMCs were potentiated by retigabine and inhibited by linopirdine, while these responses were blunted in coronary VSMCs. This study provides evidence that mouse Kv7 channels may contribute differently to regulating the functional properties of cerebral and coronary arteries. Such heterogeneity has important implications for developing novel therapeutics for cardiovascular dysfunction. PMID:25476662

Anomalous Origin of Coronary Artery From Main Pulmonary Artery in Hypoplastic Left Heart Syndrome.

PubMed

Turiy, Yuliya; Douglas, William; Balaguru, Duraisamy

2015-12-01

We report a case of anomalous origin of the left anterior descending coronary artery (LAD) from the main pulmonary artery in a child with hypoplastic left heart syndrome (mitral atresia/aortic atresia). Mechanical circulatory support was necessary because of the inability to wean from cardiopulmonary bypass after the Norwood procedure. The patient died at 4 months of age having continued depressed right ventricular function. The diagnosis was made during a catheterization performed 6 weeks after surgery because of concern for stenosis of Blalock-Taussig shunt. We believe his prolonged postoperative recovery and eventual demise can partially be attributed to lack of cardioplegia to the anomalous LAD territory during surgery. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Pacing from the right ventricular septum: is there a danger to the coronary arteries?

PubMed

Teh, Andrew W; Medi, Caroline; Rosso, Raphael; Lee, Geoffrey; Gurvitch, Ronen; Mond, Harry G

2009-07-01

Pacing from right ventricular (RV) septal sites has been suggested as an alternative to RV apical pacing in an attempt to avoid long-term adverse consequences on left ventricular function. Concern has been raised as to the relationship of the left anterior descending coronary artery (LAD) to pacing leads in these positions. We retrospectively analyzed three cases in which patients with RV active-fixation leads in situ also had coronary angiography. Multiple fluoroscopic views were used to determine the relationship of the lead tip at various pacing sites to the coronary arteries. A lead placed on the anterior wall was in close proximity to the LAD, whereas septal and free wall positioning was not. Placement of RV active-fixation leads on the septum avoids potential coronary artery compromise.

Linear IgA disease associated with ulcerative colitis: the role of surgery.

PubMed

Watchorn, R E; Ma, S; Gulmann, C; Keogan, M; O'Kane, M

2014-04-01

The association of linear IgA disease (LAD) with ulcerative colitis (UC) is well documented. One hypothesis for the association proposes immune exposure to autoantigens present in the colon, and subsequent targeting of these autoantigens in the skin. There are variable reports on the effect of bowel surgery on skin disease in such patients. We report a patient with LAD and UC who required colectomy to control her UC, but whose skin disease failed to resolve following surgery. A literature review revealed that in reported cases of this association, proctocolectomy has resulted in remission of skin disease in all cases where it has been performed, in contrast to variable results seen in cases where colectomy alone was performed. © 2014 British Association of Dermatologists.

Comparative Efficacy of Intracoronary Allogeneic Mesenchymal Stem Cells and Cardiosphere-Derived Cells in Swine with Hibernating Myocardium

PubMed Central

Weil, Brian R.; Suzuki, Gen; Leiker, Merced M.; Fallavollita, James A.; Canty, John M.

2015-01-01

Rationale Allogeneic bone marrow-derived mesenchymal stem cells (MSCs) and cardiosphere-derived cells (CDCs) have each entered clinical trials but a direct comparison of these cell types has not been performed in a large animal model of hibernating myocardium. Objective Using completely blinded methodology, compare the efficacy of global intracoronary allogeneic MSCs (icMSCs, ~35×106) and CDCs (icCDCs, ~35×106) vs. vehicle in cyclosporine-immunosuppressed swine with a chronic LAD stenosis (n=26). Methods and Results Studies began 3-months after instrumentation when wall-thickening (%WT) was reduced (LAD%WT 38±11% (mean ± SD) vs. 83±26% in remote, p<0.01) and similar among groups. Four-weeks after treatment, LAD%WT increased similarly following icCDCs and icMSCs, while it remained depressed in vehicle-treated controls (icMSCs: 51±13%; icCDCs: 51±17%; vehicle: 34±3%, treatments p<0.05 vs. vehicle). There was no change in myocardial perfusion. Both icMSCs and icCDCs increased LAD myocyte nuclear density (icMSCs: 1601±279 nuclei/mm2, icCDCs: 1569±294 nuclei/mm2, vehicle: 973±181 nuclei/mm2, treatments p<0.05 vs. vehicle) and reduced myocyte diameter (icMSCs: 16.4±1.5 μm, icCDCs: 16.8±1.2 μm, vehicle: 20.2±3.7 μm, treatments p<0.05 vs. vehicle) to the same extent. Similar changes in myocyte nuclear density and diameter were observed in the remote region of cell-treated animals. Cell fate analysis using Y-FISH demonstrated rare cells from sex-mismatched donors. Conclusions Allogeneic icMSCs and icCDCs exhibit comparable therapeutic efficacy in a large animal model of hibernating myocardium. Both cell types produced equivalent increases in regional function and stimulated myocyte regeneration in ischemic and remote myocardium. The activation of endogenous myocyte proliferation and regression of myocyte cellular hypertrophy support a common mechanism of cardiac repair. PMID:26271689

Noninvasive Imaging of the Coronary Vasculature Using Ultrafast Ultrasound.

PubMed

Maresca, David; Correia, Mafalda; Villemain, Olivier; Bizé, Alain; Sambin, Lucien; Tanter, Mickael; Ghaleh, Bijan; Pernot, Mathieu

2017-08-11

The aim of this study was to investigate the potential of coronary ultrafast Doppler angiography (CUDA), a novel vascular imaging technique based on ultrafast ultrasound, to image noninvasively with high sensitivity the intramyocardial coronary vasculature and quantify the coronary blood flow dynamics. Noninvasive coronary imaging techniques are currently limited to the observation of the epicardial coronary arteries. However, many studies have highlighted the importance of the coronary microcirculation and microvascular disease. CUDA was performed in vivo in open-chest procedures in 9 swine. Ultrafast plane-wave imaging at 2,000 frames/s was combined to an adaptive spatiotemporal filtering to achieve ultrahigh-sensitive imaging of the coronary blood flows. Quantification of the flow change was performed during hyperemia after a 30-s left anterior descending (LAD) artery occlusion followed by reperfusion and was compared to gold standard measurements provided by a flowmeter probe placed at a proximal location on the LAD (n = 5). Coronary flow reserve was assessed during intravenous perfusion of adenosine. Vascular damages were evaluated during a second set of experiments in which the LAD was occluded for 90 min, followed by 150 min of reperfusion to induce myocardial infarction (n = 3). Finally, the transthoracic feasibility of CUDA was assessed on 2 adult and 2 pediatric volunteers. Ultrahigh-sensitive cine loops of venous and arterial intramyocardial blood flows were obtained within 1 cardiac cycle. Quantification of the coronary flow changes during hyperemia was in good agreement with gold standard measurements (r 2  = 0.89), as well as the assessment of coronary flow reserve (2.35 ± 0.65 vs. 2.28 ± 0.84; p = NS). On the infarcted animals, CUDA images revealed the presence of strong hyperemia and the appearance of abnormal coronary vessel structures in the reperfused LAD territory. Finally, the feasibility of transthoracic coronary vasculature imaging was shown on 4 human volunteers. Ultrafast Doppler imaging can map the coronary vasculature with high sensitivity and quantify intramural coronary blood flow changes. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Early and mid-term results of off-pump endarterectomy of the left anterior descending artery

PubMed Central

Takahashi, Mitsuko; Gohil, Sunir; Tong, Bonnie; Lento, Patrick; Filsoufi, Farzan; Reddy, Ramachandra C.

2013-01-01

OBJECTIVES Many patients referred for coronary artery bypass surgery (CABG) today have diffusely diseased coronary vessels, and some of them may require coronary endarterectomy to provide adequate revascularization. Most reports of coronary endarterectomy describe an on-pump procedure. As off-pump coronary artery bypass graft has become safer and more routine, there is renewed interest in off-pump coronary endarterectomy. We report on our series of patients who underwent off-pump coronary endarterectomy of the left anterior descending (LAD) artery using an open endarterectomy technique. METHODS All patients undergoing open heart surgery at The Mount Sinai Medical Center are entered into a state-mandated, audited database. A retrospective review of this database revealed 12 patients between January 2008 and June 2012 who underwent off-pump endarterectomy of the LAD as part of their coronary revascularization. Additional data were collected from a review of the patients' charts. RESULTS There were a total of 12 patients, with a mean age of 72 ± 4 years. Nine (75%) were male and 3 (25%) were female. Comorbidities included hypertension in 11 (92%) patients, dyslipidaemia in 10 (83%), diabetes in 8 (67%), renal failure in 6 (50%) and stroke in 1 (8%). The mean number of diseased coronary territories was 3 ± 0.4 (range 2–3), and the mean number of coronary bypass grafts performed was 4 ± 0.8 (range 2–5). Eight patients required transfusion with packed red blood cells (67%). One (8%) patient was converted from off-pump to on-pump. The mean intensive care unit stay was 3 ± 2.8 (range 1–8 days), and the mean hospital length of stay was 15 ± 13 (range 4–54 days). Postoperative follow-up (mean 24 ± 19 months, range 1–53) is complete, and no ischaemic events have occurred in the early and mid-term follow-up period. CONCLUSIONS We conclude that off-pump endarterectomy of the LAD is a viable option for patients with diffuse LAD disease. PMID:23190620

Assessment of Atrial Fibrillation and Ventricular Arrhythmia Risk after Bariatric Surgery by P Wave/QT Interval Dispersion.

PubMed

Yılmaz, Mustafa; Altın, Cihan; Tekin, Abdullah; Erol, Tansel; Arer, İlker; Nursal, Tarık Zafer; Törer, Nurkan; Erol, Varlık; Müderrisoğlu, Haldun

2018-04-01

The association of obesity with atrial fibrillation (AF) and with ventricular arrhythmias is well documented. The aim of this study was to investigate whether weight reduction by a laparoscopic sleeve gastrectomy has any effect on P wave dispersion (PWD), a predictor of AF, and corrected QT interval dispersion (CQTD), a marker of ventricular arrhythmias, in obese individuals. In a prospective study, a total of 114 patients (79 females, 35 males) who underwent laparoscopic sleeve gastrectomy were examined. The patients were followed 1 year. PWD and CQTD values before and 3rd, 6th, and 12th months after the surgery were calculated and compared. There was a statistically significant decline in body mass index (BMI), PWD, and CQTD values among baseline, 3rd, 6th, and 12th months (p < 0.001 for all comparisons). Correlation analysis showed a statistically significant correlation between ΔPWD and ΔBMI (r = 0.719, p < 0.001), ΔPWD and Δleft ventricular end-diastolic diameter (LVEDD) (r = 0.291, p = 0.002), ΔPWD and Δleft atrial diameter (LAD) (r = 0.65, p < 0.001), ΔCQTD and ΔBMI (r = 0.266, p = 0.004), ΔCQTD and ΔLVEDD (r = 0.35, p < 0.001), ΔCQTD and ΔLAD (r = 0.289, p = 0.002). In multiple linear regression analysis, there was a statistically significant relationship between ΔPWD and ΔBMI (β = 0.713, p < 0.001), ΔPWD and ΔLVEDD (β = 0.174, p = 0.016), ΔPWD and ΔLAD (β = 0.619, p < 0.001), ΔCQTD and ΔBMI (β = 0.247, p = 0.011), ΔCQTD and ΔLVEDD (β = 0.304, p < 0.001), ΔCQTD and ΔLAD (β = 0.235, p = 0.009). PWD and CQTD values of patients were shown to be attenuated after bariatric surgery. These results indirectly offer that there may be a reduction in risk of AF, ventricular arrhythmia, and sudden cardiac death after obesity surgery.

Myocardial Uptake of 7′-(Z)-[123I]Iodorotenone During Vasodilator Stress in Dogs With Critical Coronary Stenoses

PubMed Central

Broisat, Alexis; Ruiz, Mirta; Goodman, Norman C.; Hanrahan, Stephen M.; Reutter, Bryan W.; Brennan, Kathleen M.; Janabi, Mustafa; Schaefer, Saul; Watson, Denny D.; Beller, George A.; VanBrocklin, Henry F.; Glover, David K.

2013-01-01

Background There is a well-recognized need for a new generation of single photon emission computed tomography (SPECT) perfusion tracers with improved myocardial extraction over a wide flow range. Radiotracers that target complex I of the mitochondrial electron transport chain have been proposed as a new class of myocardial perfusion imaging agents. 7-(Z)-[125I]iodorotenone (125I-ZIROT) has demonstrated superior myocardial extraction and retention characteristics in rats and in isolated perfused rabbit hearts. We sought to fully characterize the biodistribution and myocardial extraction versus flow relationship of 123I-ZIROT in an intact large-animal model. Methods and Results The 123I-ZIROT was administered during adenosine A2A agonist-induced hyperemia in 5 anesthetized dogs with critical left anterior descending (LAD) stenoses. When left circumflex (LCx) flow was maximal, 123I-ZIROT and microspheres were coinjected and the dogs were euthanized 5 minutes later. 123I-ZIROT biodistribution was evaluated in 2 additional dogs by in vivo planar imaging. At 123I-ZIROT injection, transmural LAD flow was unchanged from baseline (mean±SEM, 0.90±0.22 versus 0.87±0.11 mL/[min · g]; P=0.92), whereas LCx zone flow increased significantly (mean±SEM, 3.25±0.51 versus 1.00±0.17 mL/[min · g]; P<0.05). Myocardial 123I-ZIROT extraction tracked regional myocardial flow better than either thallium-201 or 99mTc-sestamibi from previous studies using a similar model. Furthermore, the 123I-ZIROT LAD/LCx activity ratios by ex vivo imaging or well counting (mean±SEM, 0.42±0.08 and 0.45±0.1, respectively) only slightly underestimated the LAD/LCx microsphere flow ratio (0.32±0.09). Conclusions The ability of 123I-ZIROT to more linearly track blood flow over a wide range makes it a promising new SPECT myocardial perfusion imaging agent with potential for improved coronary artery disease detection and better quantitative estimation of the severity of flow impairment. PMID:21917783

Current status of cardiovascular surgery in Japan, 2013 and 2014: A report based on the Japan Cardiovascular Surgery Database 3. Coronary artery bypass surgery.

PubMed

Saito, Aya; Hirahara, Norimichi; Motomura, Noboru; Miyata, Hiroaki; Takamoto, Shinichi

2018-01-01

Data on isolated coronary artery bypass grafting (CABG) performed in 2013 and 2014, and registered in the Japan Cardiovascular Surgery Database were reviewed for preoperative characteristics, postoperative outcomes, and choice of graft material for the left anterior descending artery (LAD). Isolated CABG was performed off-pump in 54.7% of cases, and graft material for the LAD was left internal thoracic artery in 74.3% and right internal thoracic artery in 15.6%. Operative mortality was 2.0% in elective cases, 8.2% in emergency cases, and 3.0% overall. In elective cases, operative mortality was 1.1% for off-pump CABG compared with 3.0% for on-pump CABG. Clinical results of our isolated CABG were reasonable and acceptable.

Assessment of deformation of the mitral valve complex during off-pump coronary artery bypass surgery using three-dimensional echocardiography in a porcine model.

PubMed

Igarashi, Takashi; Iwai-Takano, Masumi; Wakamatsu, Hiroki; Haruta, Mineyuki; Omata, Sadao; Yokoyama, Hitoshi

2018-01-01

This study aimed to assess the deformation of the mitral valve complex during the displacement of the beating heart by using three-dimensional echocardiography in a porcine off-pump coronary artery bypass grafting (OPCAB) model. In nine healthy swine, we positioned the beating heart as an OPCAB model, i.e. control, left anterior descending artery (LAD), right coronary artery (RCA), and left circumflex artery (LCX) positions. In each position, three-dimensional echocardiography was performed to assess the mitral valve complex with hemodynamic parameters. We analyzed the deformation of the mitral valve and the three-dimensional coordinates of the papillary muscles. There was a significant increase in maximum tenting length and tenting volume (control 0.70±0.30, LAD 0.65±0.27, RCA 0.79±0.23, LCX 0.95±0.34cm 3 , p<0.05) in the LCX position compared with the other positions. The posterior papillary muscle (PPM) angle had a significant relationship with the tenting volume (r=-0.643, p<0.001). The PPM was displaced to the medial side in the LAD and LCX positions (p<0.01). The prime cause of the deformation of the mitral leaflets is suggested to be the displacement of the PPM associated with the change in geometry of the left ventricle in a porcine model. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Clinical, Electrocardiographic, and Echocardiographic Parameter Combination Predicts the Onset of Atrial Fibrillation.

PubMed

Soeki, Takeshi; Matsuura, Tomomi; Tobiume, Takeshi; Bando, Sachiko; Matsumoto, Kazuhisa; Nagano, Hiromi; Uematsu, Etsuko; Kusunose, Kenya; Ise, Takayuki; Yamaguchi, Koji; Yagi, Shusuke; Fukuda, Daiju; Yamada, Hirotsugu; Wakatsuki, Tetsuzo; Shimabukuro, Michio; Sata, Masataka

2018-05-30

The ability to identify risk markers for new-onset atrial fibrillation (AF) is critical to the development of preventive strategies, but it remains unknown whether a combination of clinical, electrocardiographic, and echocardiographic parameters predicts the onset of AF. In the present study, we evaluated the predictive value of a combined score that includes these parameters.Methods and Results:We retrospectively studied 1,040 patients without AF who underwent both echocardiography and 24-h Holter electrocardiography between May 2005 and December 2010. During a median follow-up period of 68.4 months (IQR, 49.9-93.3 months), we investigated the incidence of new-onset AF. Of the 1,040 patients, 103 (9.9%) developed AF. Patients who developed AF were older than patients who did not. Total heart beats, premature atrial contraction (PAC) count, maximum RR interval, and frequency of sinus pause quantified on 24-h electrocardiography were associated with new-onset AF. LA diameter (LAD) on echocardiography was also associated with the development of AF. On multivariate Cox analysis, age ≥58 years, PAC count ≥80 beats/day, maximum RR interval ≥1.64 s, and LAD ≥4.5 cm were independently associated with the development of AF. The incidence rate of new-onset AF significantly increased as the combined score (i.e., the sum of the risk score determined using hazard ratios) increased. A combined score that includes age, PAC count, maximum RR interval, and LAD could help characterize the risk of new-onset AF.

Dynamic CT myocardial perfusion imaging: detection of ischemia in a porcine model with FFR verification

NASA Astrophysics Data System (ADS)

Fahmi, Rachid; Eck, Brendan L.; Vembar, Mani; Bezerra, Hiram G.; Wilson, David L.

2014-03-01

Dynamic cardiac CT perfusion (CTP) is a high resolution, non-invasive technique for assessing myocardial blood ow (MBF), which in concert with coronary CT angiography enable CT to provide a unique, comprehensive, fast analysis of both coronary anatomy and functional ow. We assessed perfusion in a porcine model with and without coronary occlusion. To induce occlusion, each animal underwent left anterior descending (LAD) stent implantation and angioplasty balloon insertion. Normal ow condition was obtained with balloon completely de ated. Partial occlusion was induced by balloon in ation against the stent with FFR used to assess the extent of occlusion. Prospective ECG-triggered partial scan images were acquired at end systole (45% R-R) using a multi-detector CT (MDCT) scanner. Images were reconstructed using FBP and a hybrid iterative reconstruction (iDose4, Philips Healthcare). Processing included: beam hardening (BH) correction, registration of image volumes using 3D cubic B-spline normalized mutual-information, and spatio-temporal bilateral ltering to reduce partial scan artifacts and noise variation. Absolute blood ow was calculated with a deconvolutionbased approach using singular value decomposition (SVD). Arterial input function was estimated from the left ventricle (LV) cavity. Regions of interest (ROIs) were identi ed in healthy and ischemic myocardium and compared in normal and occluded conditions. Under-perfusion was detected in the correct LAD territory and ow reduction agreed well with FFR measurements. Flow was reduced, on average, in LAD territories by 54%.

Real-time Visualization and Quantification of Retrograde Cardioplegia Delivery using Near Infrared Fluorescent Imaging

PubMed Central

Rangaraj, Aravind T.; Ghanta, Ravi K.; Umakanthan, Ramanan; Soltesz, Edward G.; Laurence, Rita G.; Fox, John; Cohn, Lawrence H.; Bolman, R. M.; Frangioni, John V.; Chen, Frederick Y.

2009-01-01

Background and Aim of the Study Homogeneous delivery of cardioplegia is essential for myocardial protection during cardiac surgery. Presently, there exist no established methods to quantitatively assess cardioplegia distribution intraoperatively and determine when retrograde cardioplegia is required. In this study, we evaluate the feasibility of near infrared (NIR) imaging for real-time visualization of cardioplegia distribution in a porcine model. Methods A portable, intraoperative, real-time NIR imaging system was utilized. NIR fluorescent cardioplegia solution was developed by incorporating indocyanine green (ICG) into crystalloid cardioplegia solution. Real-time NIR imaging was performed while the fluorescent cardioplegia solution was infused via the retrograde route in 5 ex-vivo normal porcine hearts and in 5 ex-vivo porcine hearts status post left anterior descending (LAD) coronary artery ligation. Horizontal cross-sections of the hearts were obtained at proximal, middle, and distal LAD levels. Videodensitometry was performed to quantify distribution of fluorophore content. Results The progressive distribution of cardioplegia was clearly visualized with NIR imaging. Complete visualization of retrograde distribution occurred within 4 minutes of infusion. Videodensitometry revealed that retrograde cardioplegia primarily distributed to the left ventricle and anterior septum. In hearts with LAD ligation, antegrade cardioplegia did not distribute to the anterior left ventricle. This deficiency was compensated for with retrograde cardioplegia supplementation. Conclusions Incorporation of ICG into cardioplegia allows real-time visualization of cardioplegia delivery via NIR imaging. This technology may prove useful in guiding intraoperative decisions pertaining to when retrograde cardioplegia is mandated. PMID:19016995

Cardio-embolic stroke following remote blunt chest trauma.

PubMed

Arora, Sonali; Atreya, Auras R; Penumetsa, Srikanth C; Hiser, William L

2013-03-01

A cardio-embolic stroke as a sequela of remote blunt chest trauma is a rare clinical presentation. Blunt chest trauma can cause various acute cardiac complications like arrhythmias, cardiac contusion etc. However, delayed consequences such as left ventricular thrombus resulting in thromboembolic phenomena are reported infrequently. A 30-year-old healthy man presented to an outside facility with transient neurological deficits. An MRI brain showed lesions suggestive of embolic etiology. A trans-thoracic echocardiogram (TTE) showed a 1.5 × 1.5 cm mass present in the left ventricular (LV) apex. Patient was transferred to our institution for cardiac surgery evaluation. On detailed questioning, he reported an incident of blunt chest trauma during a martial arts exhibition fight that took place 2 years back. Given this history, a cardiac catheterization was done, which showed 30% stenosis in mid-left anterior descending artery (LAD) without any other significant obstructive lesion. A trans-esophageal echocardiogram (TEE) showed akinesis of the LV apex and confirmed TTE finding of a mass, consistent with an apical thrombus. Surgery was deferred and patient was started on anticoagulation. A cardiac MRI done 2 weeks later showed evidence of apical infarction in the LAD territory. LAD is the most commonly affected coronary vessel by blunt traumatic injuries, likely due to its vulnerable anatomical position on the anterior aspect of the heart. A variety of mechanisms including intimal tear, rupture and spasm have been implicated in the pathogenesis of myocardial infarction after blunt chest trauma.

Distribution of tissue characteristics of coronary plaques evaluated by integrated backscatter intravascular ultrasound: Differences between the inner and outer vessel curvature.

PubMed

Sato, Hironobu; Kawasaki, Masanori; Morita, Norihiko; Fujiwara, Hisayoshi; Minatoguchi, Shinya

2015-12-01

The purpose of the present study was to evaluate the tissue characteristics of plaques with moderate or mild stenosis in the inner and outer curvature of the left anterior descending artery (LAD) using integrated backscatter intravascular ultrasound. We evaluated 66 plaques with moderate stenosis (plaque burden >50% but ≤75%) and 49 plaques with mild stenosis (plaque burden >30% but ≤50%) in 66 patients undergoing percutaneous intervention to the LAD. All plaques were >10mm away from any side branch or previously implanted stents. We divided vessel cross-sections into four quadrants (inner curvature, outer curvature, clockwise lateral side, and counterclockwise lateral side) using the septal branch as a landmark for the inner curvature. We averaged relative lipid area, relative fibrous area, and relative calcified area in minimal lumen area (MLA), three cross-sections proximal to the site of MLA, and three cross-sections distal to the site of MLA. In plaques with moderate stenosis, the relative lipid area in the inner curvature was significantly greater than in the outer curvature and lateral sides, whereas there was no significant difference in plaques with mild stenosis. The present study provides new findings that lipid pool is clustered in the inner curvature and fibrous tissue is clustered in the outer curvature of plaques with moderate stenosis in non-branching LAD lesions. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Association of dietary iron restriction with left ventricular remodeling after myocardial infarction in mice.

PubMed

Eguchi, Akiyo; Naito, Yoshiro; Iwasaku, Toshihiro; Okuhara, Yoshitaka; Morisawa, Daisuke; Sawada, Hisashi; Nishimura, Koichi; Oboshi, Makiko; Fujii, Kenichi; Mano, Toshiaki; Masuyama, Tohru; Hirotani, Shinichi

2016-02-01

Several epidemiologic studies have reported that body iron status and dietary iron intake are related to an increased risk of acute myocardial infarction (MI). However, it is completely unknown whether dietary iron reduction impacts the development of left ventricular (LV) remodeling after MI. Here, we investigate the effect of dietary iron restriction on the development of LV remodeling after MI in an experimental model. MI was induced in C57BL/6 J mice (9-11 weeks of age) by the permanent ligation of the left anterior descending coronary artery (LAD). At 2 weeks after LAD ligation, mice were randomly divided into two groups and were given a normal diet or an iron-restricted diet for 4 weeks. Sham operation without LAD ligation was also performed as controls. MI mice exhibited increased LV dilatation and impaired LV systolic function that was associated with cardiomyocyte hypertrophy and interstitial fibrosis in the remote area, as compared with the controls at 6 weeks after MI. In contrast, dietary iron restriction attenuated LV dilatation and impaired LV systolic function coupled to cardiomyocyte hypertrophy and interstitial fibrosis in the remote area. Importantly, cardiac expression of cellular iron transport proteins, transferrin receptor 1 and divalent metal transporter 1 was increased in the remote area of MI mice compared with the controls. Dietary iron restriction attenuated the development of LV remodeling after MI in mice. Cellular iron transport might play a role in the pathophysiological mechanism of LV remodeling after MI.

Analysis of the Liver Soluble Proteome from Bull Terriers Affected with Inherited Lethal Acrodermatitis

PubMed Central

Mouat, Michael F.; Mauldin, Elizabeth A.; Casal, Margret L.

2012-01-01

Lethal acrodermatitis (LAD) is a genetic disease affecting bull terrier dogs. The phenotype is similar to that for acrodermatitis enteropathica in humans, but is currently without treatment. The purpose of the research presented here is to determine the biochemical defects associated with LAD using proteomic methodologies. Two affected (male and female) and one unaffected (male) bull terrier pups were euthanized at 14 weeks of age, their livers dissected and prepared for two-dimensional gel electrophoresis (2DE) and densitometry. Approximately 200 protein spots were observed. The density of the spots within each gel was normalized to the total spot volume of the gel; only those soluble liver protein spots that were consistently different in both of the livers of the affected pups compared to the unaffected pup were excised manually and submitted for MALDI mass spectrometry. Thirteen proteins were identified as differentially expressed in the affected, compared to the unaffected, pups. The proteins were involved in numerous cellular physiological functions, including chaperones, calcium binding, and energy metabolism, as well as being associated with the inflammatory response. Of note were haptoglobin, glutamine synthetase, prohibitin and keratin 10 which exhibited at least a 4-fold level of differential expression. These data represent the first proteomic analysis of this mutation. The differentially expressed proteins that were identified may be key in understanding the etiology of LAD, and may lead to diagnostic tools for its identification within the bull terrier population. PMID:17693109

Assessment of atherosclerotic luminal narrowing of coronary arteries based on morphometrically generated visual guides.

PubMed

Barth, Rolf F; Kellough, David A; Allenby, Patricia; Blower, Luke E; Hammond, Scott H; Allenby, Greg M; Buja, L Maximilian

Determination of the degree of stenosis of atherosclerotic coronary arteries is an important part of postmortem examination of the heart, but, unfortunately, estimation of the degree of luminal narrowing can be imprecise and tends to be approximations. Visual guides can be useful to assess this, but earlier attempts to develop such guides did not employ digital technology. Using this approach, we have developed two computer-generated morphometric guides to estimate the degree of luminal narrowing of atherosclerotic coronary arteries. The first is based on symmetric or eccentric circular or crescentic narrowing of the vessel lumen and the second on either slit-like or irregularly shaped narrowing of the vessel lumens. Using the Aperio ScanScope XT at a magnification of 20× we created digital whole-slide images of 20 representative microscopic cross sections of the left anterior descending (LAD) coronary artery, stained with either hematoxylin and eosin (H&E) or Movat's pentachrome stain. These cross sections illustrated a variety of luminal profiles and degrees of stenosis. Three representative types of images were selected and a visual guide was constructed with Adobe Photoshop CS5. Using the "Scale" and "Measurement" tools, we created a series of representations of stenosis with luminal cross sections depicting 20%, 40%, 60%, 70%, 80%, and 90% occlusion of the LAD branch. Four pathologists independently reviewed and scored the degree of atherosclerotic luminal narrowing based on our visual guides. In addition, digital technology was employed to determine the degree of narrowing by measuring the cross-sectional area of the 20 microscopic sections of the vessels, first assuming no narrowing and then comparing this to the percent of narrowing determined by precise measurement. Two of the observers were very experienced general autopsy pathologists, one was a first-year pathology resident on his first rotation on the autopsy service, and the fourth observer was a highly experienced cardiovascular pathologist. Interobserver reliability was assessed by determination of the intraclass correlation coefficient. The degrees of agreement for two H&E- and Movat-stained sections of the LADs from each of 10 decedents were 0.874 and 0.899, respectively, indicating strong interobserver agreement. On the average, the mean visual scores were ~8% less than the morphometric assessment (52.7 vs. 60.2), respectively. The visual guides that we have generated for scoring atherosclerotic luminal narrowing of coronary arteries should be helpful for a broad group of pathologists, from beginning pathology residents to experienced cardiovascular pathologists. Copyright © 2017 Elsevier Inc. All rights reserved.

Rapid Flow cytometric prenatal diagnosis of primary immunodeficiency (PID) disorders.

PubMed

Mishra, Anju; Gupta, Maya; Dalvi, Aparna; Ghosh, Kanjaksha; Madkaikar, Manisha

2014-04-01

Primary Immunodeficiency diseases (PID) are a heterogeneous group of inherited disorders of immune system. Immunophenotypic evaluation of PIDs using flowcytometry provides important clues for diagnosis of these disorders, though confirmation requires identification of underlying molecular defects. Prenatal diagnosis (PND) forms an important component of management in families affected with severe PID. However, molecular diagnostic facilities for each of these diseases are not available and may not be possible to perform in all cases. In such scenario we opted for phenotypic prenatal diagnosis by cordocentesis for families with index case having immunophenotypically well characterized PID. Normal reference ranges of lymphocyte subsets, CD 18/CD11 integrins on leukocytes, MHC class II expression and oxidative burst activity of fetal neutrophils at 18 weeks of gestation were previously established on 30 cord blood samples. PND was performed in 13 families with PIDs. Maternal contamination was ruled out by VNTR analysis. Out of 13 fetuses, nine were found to be unaffected (three cases with leukocyte adhesion deficiency (LAD-I), four cases with severe combined immunodeficiency diseases (SCID), one with X-linked agammaglobulinemia (XLA), and one with chronic granulomatous disease (CGD)] and three were found to be affected (one with T-B+NK-SCID, one with MHC class II deficiency and one with LAD-I). Diagnosis was confirmed by testing the cord blood samples after delivery and further follow-up of the children. In one family diagnosis could not be offered due to maternal contamination. No procedure related complications were observed. Flowcytometry offers rapid and sensitive method for prenatal diagnosis and genetic counseling for selected phenotypically well characterized PID in cases where molecular diagnostic facilities are not available.

Is the Deep Inspiration Breath-Hold Technique Superior to the Free Breathing Technique in Cardiac and Lung Sparing while Treating both Left-Sided Post-Mastectomy Chest Wall and Supraclavicular Regions?

PubMed

Darapu, Anupama; Balakrishnan, Rajesh; Sebastian, Patricia; Hussain, Mohamathu Rafic Kather; Ravindran, Paul; John, Subhashini

2017-01-01

To evaluate the efficacy of the deep inspirational breath-hold (DIBH) technique and its dosimetric advantages over the free breathing (FB) technique in cardiac (heart and left anterior descending artery [LAD]) and ipsilateral lung sparing in left-sided post-mastectomy field-in-field conformal radiotherapy. DIBH is highly reproducible, and this study aims to find out its dosimetric benefits over FB. Nineteen left-sided mastectomy patients were immobilized using breast boards with both arms positioned above the head. All patients had 2 sets of planning CT images (one in FB and another in DIBH) with a Biograph TruePoint HD CT scanner in the same setup. DIBH was performed by tracking the respiratory cycles using a Varian Real-Time Position Management system. The target (chest wall and supraclavicular region), organs at risk (OARs; ipsilateral lung, contralateral lung, heart, LAD, and contralateral breast), and other organs of interests were delineated as per the RTOG (Radiation Therapy Oncology Group) contouring guidelines. The single-isocenter conformal fields in the field treatment plans were generated with the Eclipse Treatment Planning System (Varian Medical Systems) for both FB and DIBH images, and the doses to the target and OARs were compared. The standard fractionation regimen of 50 Gy in 25 fractions over a period of 5 weeks was used for all patients in this study. The target coverage parameters (V95, V105, V107, and D_mean) were found to be 97.8 ± 0.9, 6.1 ± 3.4, 0.2 ± 0.3, and 101.9 ± 0.5% in the FB plans and 98.1 ± 0.8, 6.1 ± 3.2, 0.2 ± 0.3, and 101.9 ± 0.4% in the DIBH plans, respectively. The plan quality indices (conformity index and homogeneity index) also showed 1.3 ± 0.2 and 0.1 for the FB plans and 1.2 ± 0.3 and 0.1 for the DIBH plans, respectively. There was a significant reduction in dose to the heart in the DIBH plans compared to the FB plans, with p values of nearly 0 for the V5, V10, V25, V30, and D_mean dosimetric parameters. The difference in ipsilateral lung doses between FB and DIBH showed statistically significant p values, and the differences in mean doses were found to be 7, 15.7, 11.8, and 10.7% for V5, V20, V30, and D_mean, respectively. There was a significant reduction in dose to the LAD in the DIBH compared to the FB plans. DIBH resulted in significant reductions in doses to the heart, LAD, and lungs, since with this technique there was an increase in the distance between the target and the OARs. With appropriate patient selection and adequate training, the DIBH technique is acceptable and achievable for radiotherapy to the chest, and therefore should be considered for all suitable patients, as this could result in fewer radiotherapy-related complications. However, this technique is time-consuming, since the setup is complex, results in an increased time for treatment delivery, and needs patient cooperation and technical expertise.

Successful transradial intervention for two lesions with dual anomalous origins of coronary arteries.

PubMed

Masuda, Naoki; Matsukage, Takashi; Ikari, Yuji

2011-05-01

A 76-year-old male was admitted to our hospital for effort angina pectoris. His coronary computed tomography and coronary angiography revealed anomalous origins of the left anterior descending artery (LAD) from the proximal right coronary artery (RCA) and the left circumflex coronary artery (LCX) from the separate ostium in the right coronary cusp. Severe stenoses were present in the proximal segment of the LAD and in the middle segment of the LCX, which were successfully treated by 5 French (Fr) transradial approach intervention. Congenital coronary anomalies are relatively rare, with a prevalence of approximately 1.3% in a large-series study undergoing coronary angiography. Such anomalies occur in several anatomical arrangements, which have been classified in a number of research reports. Here we describe previously unreported dual anomalous origins of coronary arteries associated with significant atherosclerotic lesions, which were successfully treated by 5 Fr transradial approach intervention.

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 Novel Electrocardiographic Sign of an ST-Segment Elevation Myocardial Infarction-Equivalent: De Winter Syndrome.

PubMed

Goktas, Mustafa Ugur; Sogut, Ozgur; Yigit, Mehmet; Kaplan, Onur

2017-08-01

Patients with de Winter syndrome, also termed anterior ST-segment elevation myocardial infarction (STEMI)-equivalent, represent 2% of all patients with acute anterior myocardial infarctions admitted to emergency departments (EDs). STEMI-equivalents do not present with classical electrocardiogram (ECG) changes but exhibit a critical stenosis of the left anterior descending (LAD) coronary artery. This is under-recognized by clinicians and is therefore associated with high morbidity and mortality. Here, we report a rare case of a novel, typical, STEMI-equivalent ECG pattern without obvious ST-segment elevation in a 34-year-old female who presented to our ED with substantial chest pain and a large, acute, transmural anterior myocardial infarction caused by acute occlusion of the LAD coronary artery. However, she presented as a non-STEMI case. A definite diagnosis of de Winter syndrome was made on the basis of clinical and ECG findings.

Chronological protein synthesis in regenerating rat liver.

PubMed

He, Jinjun; Hao, Shuai; Zhang, Hao; Guo, Fuzheng; Huang, Lingyun; Xiao, Xueyuan; He, Dacheng

2015-07-01

Liver regeneration has been studied for decades; however, its regulation remains unclear. In this study, we report a dynamic tracing of protein synthesis in rat regenerating liver with a new proteomic technique, (35) S in vivo labeling analysis for dynamic proteomics (SiLAD). Conventional proteomic techniques typically measure protein alteration in accumulated amounts. The SiLAD technique specifically detects protein synthesis velocity instead of accumulated amounts of protein through (35) S pulse labeling of newly synthesized proteins, providing a direct way for analyzing protein synthesis variations. Consequently, protein synthesis within short as 30 min was visualized and protein regulations in the first 8 h of regenerating liver were dynamically traced. Further, the 3.5-5 h post partial hepatectomy (PHx) was shown to be an important regulatory turning point by acute regulation of many proteins in the initiation of liver regeneration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A 21-35 kDa Mixed Protein Component from Helicobacter pylori Activates Mast Cells Effectively in Chronic Spontaneous Urticaria.

PubMed

Tan, Ran-Jing; Sun, He-Qiang; Zhang, Wei; Yuan, Han-Mei; Li, Bin; Yan, Hong-Tao; Lan, Chun-Hui; Yang, Jun; Zhao, Zhuo; Wu, Jin-Jin; Wu, Chao

2016-12-01

Helicobacter pylori (H. pylori) seem to involve in the etiology of chronic spontaneous urticaria (CSU). But studies of the pathogenic mechanism are very little. In this study, we detected the serum-specific anti-H. pylori IgG and IgE antibodies in 211 CSU and 137 normal subjects by enzyme-linked immunosorbent assay (ELISA), evaluated the direct activation effects of H. pylori preparations and its protein components on human LAD 2 mast cell line in vitro, and analyzed the specific protein ingredients and functions of the most effective H. pylori mixed protein component using liquid chromatography-mass spectrometry and ELISA assay. In CSU patients, the positive rate of anti-H. pylori IgG positive rate was significantly higher than that in normal controls, and the anti-H. pylori IgE levels had no statistical difference between H. pylori-infected patients with and without CSU. Further studies suggested that H. pylori preparations can directly activate human LAD 2 mast cell line in a dose-dependent manner and its most powerful protein component was a mixture of 21-35 kDa proteins. Moreover, the 21-35 kDa mixed protein component mainly contained 23 kinds of proteins, which can stimulate the release of histamine, TNF-a, IL-3, IFN-γ, and LTB4 by LAD 2 cells in a dose-dependent or time-dependent manner. A 21-35 kDa mixed protein component should be regarded as the most promising pathogenic factor contributing to the CSU associated with H. pylori infection. © 2016 John Wiley & Sons Ltd.

Association of soda consumption with subclinical cardiac remodeling in the Framingham Heart Study

PubMed Central

Andersson, Charlotte; Sullivan, Lisa; Benjamin, Emelia J.; Aragam, Jayashri; Jacques, Paul; Cheng, Susan; Vasan, Ramachandran S.

2014-01-01

Objective Diet soda consumption increases cardiometabolic risk. The aim of this investigation was to assess the relations between self-reported soda consumption and subclinical cardiac remodeling. Methods We assessed the relations between self-reported soda consumption and left ventricular mass (LVM) and left atrial dimension (LAD) (both standardized within sex) in a sample of middle-aged attendees from the Framingham Heart Offspring cohort examination 5 and 6. Results The overall mean age was 55 years and 59% of the participants were women. Compared to non-consumers (n=1010), soda consumers (n=3192) had greater body weight (mean 86 vs. 82 kg among men, and 70 vs. 67 kg among women). Compared with non-consumers, age- and height-adjusted LAD was increased (standard deviation units) among soda consumers by 0.15 standard error 0.042, p<0.001) for those drinking >0–7 diet soda (n=1023), −0.010 (0.043, p=0.82) for people drinking >0–7 regular soda (n=907), 0.22 (0.057, p<0.0001) for individuals consuming >7 diet soda (n=372), and 0.20 (0.092, p=0.034) for participants drinking >7 regular soda (n=116) per week. LVM was increased among participants consuming diet soda (p<0.05), but not in regular soda consumers (p>0.05). Upon adjustment for weight, however, all aforementioned associations were attenuated. Conclusion The observed associations between soda consumption and LAD or LVM were likely related to the greater body weight of soda drinkers relative to non-drinkers. PMID:25456096

Association of soda consumption with subclinical cardiac remodeling in the Framingham heart study.

PubMed

Andersson, Charlotte; Sullivan, Lisa; Benjamin, Emelia J; Aragam, Jayashri; Jacques, Paul; Cheng, Susan; Vasan, Ramachandran S

2015-02-01

Diet soda consumption increases cardiometabolic risk. The aim of this investigation was to assess the relations between self-reported soda consumption and subclinical cardiac remodeling. We assessed the relations between self-reported soda consumption and left ventricular mass (LVM) and left atrial dimension (LAD) (both standardized within sex) in a sample of middle-aged attendees from the Framingham Heart Offspring cohort examination 5 and 6. The overall mean age was 55 years and 59% of the participants were women. Compared to non-consumers (n=1010), soda consumers (n=3192) had greater body weight (mean 86 vs. 82 kg among men, and 70 vs. 67 kg among women). Compared with non-consumers, age- and height-adjusted LAD was increased (standard deviation units) among soda consumers by 0.15 standard error 0.042, (p<0.001) for those drinking >0-7 diet soda (n=1023), -0.010 (0.043, p=0.82) for people drinking >0-7 regular soda (n=907), 0.22 (0.057, p<0.0001) for individuals consuming >7 diet soda (n=372), and 0.20 (0.092, p=0.034) for participants drinking >7 regular soda (n=116) per week. LVM was increased among participants consuming diet soda (p<0.05), but not in regular soda consumers (p>0.05). Upon adjustment for weight, however, all aforementioned associations were attenuated. The observed associations between soda consumption and LAD or LVM were likely related to the greater body weight of soda drinkers relative to non-drinkers. Copyright © 2015 Elsevier Inc. All rights reserved.

Nonuniformity of axial and circumferential remodeling of large coronary veins in response to ligation.

PubMed

Choy, Jenny Susana; Dang, Quang; Molloi, Sabee; Kassab, Ghassan S

2006-04-01

The pressure-induced remodeling of coronary veins is important in coronary venous retroperfusion. Our hypothesis is that the response of the large coronary veins to pressure overload will depend on the degree of myocardial support. Eleven normal Yorkshire swine from either sex, weighing 31-39 kg, were studied. Five pigs underwent ligation of the left anterior descending (LAD) vein, and six served as sham-operated controls. The ligation of the coronary vein caused an increase in pressure intermediate to arterial and venous values. After 2 wk of ligation, the animals were euthanized and the coronary vessels were perfusion-fixed with glutaraldehyde. The LAD vein was sectioned, and detailed morphometric measurements were made along its length from the point of ligation near the base down to the apex of the heart. The structural remodeling of the vein was circumferentially nonuniform because the vein is partially embedded in the myocardium; it was also axially nonuniform because it is tethered to the myocardium to different degrees along its axial length. The wall area was significantly larger in the experimental group, whereas luminal area in the proximal LAD vein was significantly smaller in the same group compared with sham-operated controls. The wall thickness-to-radius ratio was also significantly larger in the experimental group in proportion to the increase in pressure. The major conclusion of this study is that the response of the vein depends on the local wall stress, which is, in part, determined by the surrounding tissue. Furthermore, the geometric remodeling of the coronary vein restores the circumferential stress to the homeostatic value.

Neuroplastic changes in the sensorimotor cortex associated with orthodontic tooth movement in rats.

PubMed

Sood, Mandeep; Lee, Jye-Chang; Avivi-Arber, Limor; Bhatt, Poolak; Sessle, Barry J

2015-07-01

Orthodontic tooth movement (OTM) causes transient pain and changes in the dental occlusion that may lead to altered somatosensory inputs and patterns of mastication. This study used intracortical microstimulation (ICMS) and electromyographic (EMG) recordings to test whether neuroplastic changes occur in the ICMS-defined motor representations of left and right anterior digastric (LAD, RAD), masseter, buccinator, and genioglossus (GG) muscles within the rat's face primary motor cortex (face-M1) and adjacent face primary somatosensory cortex (face-S1) during OTM. Analyses included any changes in the number of ICMS sites representing these muscles and in the onset latencies of ICMS-evoked responses in the muscles. Sprague-Dawley rats were divided into experimental (E), sham (S), and naive (N) groups; OTM was induced in the E group. Statistical analyses involved a mixed model repeated-measures analysis of variance (MMRM ANOVA). OTM resulted in significant neuroplastic changes in the number of positive sites in the E group for LAD, RAD, and GG muscles in face-M1 and face-S1 at days 1, 7, and 28 of continuous orthodontic force application, and in the number of sites in face-M1 from which ICMS could simultaneously evoke EMG responses in different combinations of LAD, RAD, and GG muscles. However, the onset latencies of ICMS-evoked responses were not significantly different between groups or between face-M1 and face-S1. The neuroplastic changes documented in this study may reflect adaptive sensorimotor changes in response to the altered environment in the oral cavity induced by OTM. © 2015 Wiley Periodicals, Inc.

CD52 is expressed on human mast cells and is a potential therapeutic target in Waldenstrom's Macroglobulinemia and mast cell disorders.

PubMed

Santos, Daniel Ditzel; Hatjiharissi, Evdoxia; Tournilhac, Olivier; Chemaly, Mariana Z A; Leleu, Xavier; Xu, Lian; Patterson, Christopher; Branagan, Andrew R; Manning, Robert J; Ho, Allen W; Hunter, Zachary R; Dimmock, Elizabeth A; Kutok, Jeffery L; Churchill, Winthrop H; Castells, Mariana C; Tai, Yu-Tzu; Anderson, Kenneth C; Treon, Steven P

2006-05-01

Alemtuzumab is a monoclonal antibody used in the treatment of CD52-expressing B-cell malignancies, including Waldenstrom's macroglobulinemia (WM). Recent studies demonstrate high levels of alemtuzumab activity in relapsed/refractory disease. One potential target of alemtuzumab is bone marrow mast cells (BMMCs), which provide growth and survival signaling for WM lymphoplasmacytic cells. We therefore examined BMMCs (FceRI+, CD117+) from WM and other mast cell (MC) disorders for expression of CD52. We identified cell surface antigen expression by multicolor flow cytometric analysis and found CD52 expressed on human mast-derived cell line-1 (HMC-1) and LAD2 MC lines, on BMMC from 13 of 15 patients with WM, and on BMMCs from 4 of 4 patients with systemic mastocytosis (SM). None of 4 healthy donors expressed CD52. Reverse-transcriptase polymerase chain reaction analysis confirmed CD52 expression in the HMC-1 and LAD2 MC lines, in BMMCs from 14 of 15 patients with WM, and 3 of 3 patients with SM. CD52 transcripts were also detected in BMMCs from 6 of 6 healthy donors, despite the absence of CD52 cell surface expression. Importantly, we observed high levels of alemtuzumab-mediated, antibody-dependent, cell-mediated cytotoxicity against LAD2 MCs and BMMCs from patients with WM and SM. These studies demonstrate that CD52 is widely expressed on human MCs and WM bone marrow lymphoplasmacytic cells and provide the preclinical rationale for the use of alemtuzumab in the treatment of WM and possibly other MC-related disorders.

Thrombolysis in myocardial infarction frame count in coronary arteries without visible atherosclerosis in coronary angiography of patients with stable coronary artery disease.

PubMed

Tacoy, Gulten A; Yazici, Guliz E; Kocaman, Sinan A; Ozdemir, Murat H

2009-06-01

To investigate the thrombolysis in myocardial infarction (TIMI) frame count (TFC) in the coronary arteries without visible atherosclerosis in coronary angiography of patients with stable coronary artery disease (CAD). Eighty-three patients (mean age 58+/-10, 31 [37%] males), who underwent coronary angiographic evaluation for stable angina in Gazi University, Ankara, Turkey, Cardiology clinic between 2006-2007 were enrolled. Forty patients with normal coronary arteries were defined as group I. Group II consisted of 43 patients, who have one normal coronary artery in the setting of stable CAD defined as stenoses 50% or greater in at least one major coronary artery. Coronary blood flow and microvascular perfusion was evaluated by TFC. In group II, the TFC of left anterior descending artery (LAD) in 15 patients, TFC of circumflex artery (CX) in 18 patient, and TFC of right coronary artery (RCA) in 10 patients were evaluated. In group II, the TFC of LAD (37+/-12 versus 29+/-12, p=0.015) and CX (22+/-8 versus 18+/-9, p=0.035) were significantly higher than those in group I. The TFC of RCA was similar between groups (17+/-9 versus 17+/-8, p=0.990). After the adjustment of the risk factors by multivariate regression analyses, the association between TFC and clinical characteristic was statistically non-significant. The TFC decreased in angiographically normal LAD and CX arteries in the setting of stable angina pectoris. The important predictor was CAD alone, irrespective of the clinical parameters.

Coronary artery calcification identification and labeling in low-dose chest CT images

NASA Astrophysics Data System (ADS)

Xie, Yiting; Liu, Shuang; Miller, Albert; Miller, Jeffrey A.; Markowitz, Steven; Akhund, Ali; Reeves, Anthony P.

2017-03-01

A fully automated computer algorithm has been developed to evaluate coronary artery calcification (CAC) from lowdose CT scans. CAC is identified and evaluated in three main coronary artery groups: Left Main and Left Anterior Descending Artery (LM + LAD) CAC, Left Circumflex Artery (LCX) CAC, and Right Coronary Artery (RCA) CAC. The artery labeling is achieved by segmenting all CAC candidates in the heart region and applying geometric constraints on the candidates using locally pre-identified anatomy regions. This algorithm was evaluated on 1,359 low-dose ungated CT scans, in which each artery CAC content was categorically visually scored by a radiologist into none, mild, moderate and extensive. The Spearman correlation coefficient R was used to assess the agreement between three automated CAC scores (Agatston-weighted, volume, and mass) and categorical visual scores. For Agatston-weighted automated scores, R was 0.87 for total CAC, 0.82 for LM + LAD CAC, 0.66 for LCX CAC and 0.72 for RCA CAC; results using volume and mass scores were similar. CAC detection sensitivities were: 0.87 for total, 0.82 for LM + LAD, 0.65 for LCX and 0.74 for RCA. To assess the impact of image noise, the dataset was further partitioned into three subsets based on heart region noise level (low<=80HU, medium=(80HU, 110HU], high>110HU). The low and medium noise subsets had higher sensitivities and correlations than the high noise subset. These results indicate that location specific heart risk assessment is possible from low-dose chest CT images.

Preserved hyperaemic response in supraclavicular ultrasonography demonstrates function on demand of the LIMA to LAD string sign graft after CABG.

PubMed

Hartman, J M; Kelder, H C; Ackerstaff, R G A; Swieten, H A; Vermeulen, F E E; Bogers, A J J C

2007-02-01

To correlate supraclavicular ultrasonography with angiographically patent and string sign left internal mammary artery (LIMA) to left anterior descending artery (LAD) grafts. Sixteen patients with a single LIMA anastomosis to the LAD were prospectively entered in a follow-up study. The supraclavicular ultrasonography of the LIMA origin was studied preoperatively and at 5.3+/-3.6 months and 1.7+/-0.4 year postoperatively. At the late postoperative ultrasonography electrocardiographically controlled hyperemic response was also studied for 6 min. Control angiography was performed at 1.5+/-0.8 year. Differences within groups were tested with a paired t-test and between groups with an unpaired t-test. Control angiography showed in 13 patients (group I) a patent LIMA graft and in 3 patients (group II) a string sign LIMA graft. Preoperative blood velocities were not significantly different between groups. Postoperatively, both groups revealed higher diastolic and lower systolic blood velocities compared to preoperative values. The blood velocities at rest did not change in group I and all velocities decreased in group II in time postoperatively. The blood velocities in maximal hyperemic response increased significantly within the groups and were not significantly different between the groups. No ischemia could be detected electrocardiographically during hyperemic response and no patient presented angina. Both groups showed a shift towards coronary type diastolic blood velocities at rest and at hyperaemic response. Significant hyperemic response was also present in string sign LIMA grafts and demonstrates response capacity to increased myocardial oxygen demand.

Effects of 4 classes of cardiovascular drugs on ventricular function in dogs with mitral regurgitation.

PubMed

Nakayama, Tomohiro; Nishijima, Yoshinori; Miyamoto, Mutsumi; Hamlin, Robert L

2007-01-01

There have been few trials in which dogs with mitral regurgitation (MR) have been treated with various cardioactive drugs to determine effects on left ventricular (LV) function. Four classes of cardiovascular drugs may improve LV function in dogs with MR without increasing MR. Nine mature dogs were included in the study. MR was produced in 9 dogs. Five months later under butorphanol narcosis, parameters of LV function and left atrial dimension (LAD) were monitored by LV micromanometry and echocardiography/Doppler. Dogs were given (in random order) enalaprilat, nitroglycerine, ouabain, milrinone, and placebo. Nitroglycerin produced no significant change; milrinone and ouabain increased contractility; ouabain decreased heart rate; and there was evidence that enalaprilat and milrinone decreased LAD. Milrinone and ouabain decreased isovolumetric contraction time and therefore the time available for MR. There was no evidence that a positive inotrope increased MR despite increasing LV contractility and stroke volume. This study contradicts the hypotheses that (1) strengthening the left ventricle may increase MR and (2) treatment of MR (even before symptoms of heart failure develop) may decrease LAD. It is reasonable that strengthening the force of LV contraction should increase the driving pressure for MR; however, this effect did not appear to increase MR. Although some investigators believe that treating dogs with MR with afterload reducers and decreasing hindrance to ejection of blood from the LV to aorta may lengthen life by decreasing MR, there did not appear to be a reduction in MR, at least in response to the angiotensin-converting enzyme (ACE) inhibitor.

Signaling through the Phosphatidylinositol 3-Kinase (PI3K)/Mammalian Target of Rapamycin (mTOR) Axis Is Responsible for Aerobic Glycolysis mediated by Glucose Transporter in Epidermal Growth Factor Receptor (EGFR)-mutated Lung Adenocarcinoma*

PubMed Central

Makinoshima, Hideki; Takita, Masahiro; Saruwatari, Koichi; Umemura, Shigeki; Obata, Yuuki; Ishii, Genichiro; Matsumoto, Shingo; Sugiyama, Eri; Ochiai, Atsushi; Abe, Ryo; Goto, Koichi; Esumi, Hiroyasu; Tsuchihara, Katsuya

2015-01-01

Oncogenic epidermal growth factor receptor (EGFR) signaling plays an important role in regulating global metabolic pathways, including aerobic glycolysis, the pentose phosphate pathway (PPP), and pyrimidine biosynthesis. However, the molecular mechanism by which EGFR signaling regulates cancer cell metabolism is still unclear. To elucidate how EGFR signaling is linked to metabolic activity, we investigated the involvement of the RAS/MEK/ERK and PI3K/AKT/mammalian target of rapamycin (mTOR) pathways on metabolic alteration in lung adenocarcinoma (LAD) cell lines with activating EGFR mutations. Although MEK inhibition did not alter lactate production and the extracellular acidification rate, PI3K/mTOR inhibitors significantly suppressed glycolysis in EGFR-mutant LAD cells. Moreover, a comprehensive metabolomics analysis revealed that the levels of glucose 6-phosphate and 6-phosphogluconate as early metabolites in glycolysis and PPP were decreased after inhibition of the PI3K/AKT/mTOR pathway, suggesting a link between PI3K signaling and the proper function of glucose transporters or hexokinases in glycolysis. Indeed, PI3K/mTOR inhibition effectively suppressed membrane localization of facilitative glucose transporter 1 (GLUT1), which, instead, accumulated in the cytoplasm. Finally, aerobic glycolysis and cell proliferation were down-regulated when GLUT1 gene expression was suppressed by RNAi. Taken together, these results suggest that PI3K/AKT/mTOR signaling is indispensable for the regulation of aerobic glycolysis in EGFR-mutated LAD cells. PMID:26023239

The continuum spectral characteristics of gamma-ray bursts observed by BATSE

NASA Technical Reports Server (NTRS)

Pendleton, Geoffrey N.; Paciesas, William S.; Briggs, Michael S.; Mallozzi, Robert S.; Koshut, Tom M.; Fishman, Gerald J.; Meegan, Charles A.; Wilson, Robert B.; Harmon, Alan B.; Kouveliotou, Chryssa

1994-01-01

Distributions of the continuum spectral characteristics of 260 bursts in the first Burst And Transient Source Experiement (BATSE) catalog are presented. The data are derived from flux calculated from BATSE Large Area Detector (LAD) four-channel discriminator data. The data are converted from counts to protons using a direct spectral inversion technique to remove the effects of atmospheric scattering and the energy dependence of the detector angular response. Although there are intriguing clusters of bursts in the spectral hardness ratio distributions, no evidence for the presence of distinct burst classes based in spectral hardness ratios alone is found. All subsets of bursts selected for their spectral characteristics in this analysis exhibit spatial distributions consistent with isotropy. The spectral diversity of the burst population appears to be caused largely by the highly variable nature of the burst production mechanisms themselves.

Comparison of doses and NTCP to risk organs with enhanced inspiration gating and free breathing for left-sided breast cancer radiotherapy using the AAA algorithm.

PubMed

Edvardsson, Anneli; Nilsson, Martin P; Amptoulach, Sousana; Ceberg, Sofie

2015-04-10

The purpose of this study was to investigate the potential dose reduction to the heart, left anterior descending (LAD) coronary artery and the ipsilateral lung for patients treated with tangential and locoregional radiotherapy for left-sided breast cancer with enhanced inspiration gating (EIG) compared to free breathing (FB) using the AAA algorithm. The radiobiological implication of such dose sparing was also investigated. Thirty-two patients, who received tangential or locoregional adjuvant radiotherapy with EIG for left-sided breast cancer, were retrospectively enrolled in this study. Each patient was CT-scanned during FB and EIG. Similar treatment plans, with comparable target coverage, were created in the two CT-sets using the AAA algorithm. Further, the probability of radiation induced cardiac mortality and pneumonitis were calculated using NTCP models. For tangential treatment, the median V25Gy for the heart and LAD was decreased for EIG from 2.2% to 0.2% and 40.2% to 0.1% (p < 0.001), respectively, whereas there was no significant difference in V20Gy for the ipsilateral lung (p = 0.109). For locoregional treatment, the median V25Gy for the heart and LAD was decreased for EIG from 3.3% to 0.2% and 51.4% to 5.1% (p < 0.001), respectively, and the median ipsilateral lung V20Gy decreased from 27.0% for FB to 21.5% (p = 0.020) for EIG. The median excess cardiac mortality probability decreased from 0.49% for FB to 0.02% for EIG (p < 0.001) for tangential treatment and from 0.75% to 0.02% (p < 0.001) for locoregional treatment. There was no significant difference in risk of radiation pneumonitis for tangential treatment (p = 0.179) whereas it decreased for locoregional treatment from 6.82% for FB to 3.17% for EIG (p = 0.004). In this study the AAA algorithm was used for dose calculation to the heart, LAD and left lung when comparing the EIG and FB techniques for tangential and locoregional radiotherapy of breast cancer patients. The results support the dose and NTCP reductions reported in previous studies where dose calculations were performed using the pencil beam algorithm.

Testing Solar Flare Models with BATSE

NASA Astrophysics Data System (ADS)

Zarro, Dominic M.

1995-07-01

We propose to use high-sensitivity Burst and Transient Source Experiment (BATSE) hard X-ray observations to test the thick-target and electric field acceleration models of solar flares. We will compare the predictions made by these models with hard X-ray spectral observations obtained with BATSE and simultaneous soft X-ray Ca XIX emission observed with the Yohkoh Bragg Crystal Spectrometer (BCS). The increased sensitivities of the BATSE and BCS (relative to previous detectors) permits a renewed study of the relationship between heating and dynamical motions during the crucial rise phase of flares. With these observations, we will: (1) investigate the ability of the thick-target model to explain the temporal evolution of hard X-ray emission relative to the soft X-ray blueshift during the earliest stages of the impulsive phase; and (2) search for evidence of electric-field acceleration as implied by temporal correlations between hard X-ray spectral breaks and the Ca XIX blueshift. The proposed study will utilize hard X-ray lightcurve and spectral measurements in the 10-100 keV energy range obtained with the BATSE Large Area Detectors (LAD). The DISCLA and CONT data will be the primary data products used in this analysis.

The reflection for dense plant canopies from the one-angle radiative transfer equation

NASA Technical Reports Server (NTRS)

Ganapol, B. D.; Lawless, James G. (Technical Monitor)

1994-01-01

An essential component of remote sensing of vegetation canopies from satellites is fundamental understanding. Since passive remote is driven by photons, the modeling of photon interactions with vegetation is a basic building block in that understanding. Several such photon transport models have been developed during the past two decades and continue to be developed. Different approaches have been followed including monte carlo, radiosity methods, geometric shadowing, and radiative transfer. In general, each approach has application for canopies with specific attributes. This presentation concerns the application of radiative transfer to dense vegetation canopies in which the soil does not participate. The approach taken here is novel in that a consistent theory for photon transport for non-rotationally invariant leaf scattering is developed in a canopy with a general leaf angle distribution (LAD). The theory is limited to the one-angle approximation (azimuthally averaged radiance) and is based on Chandrasekhar's analytical theory. While such a model is admittedly only approximate, it does fulfill a unique function in our search for understanding. In particular, the model is simple in its construct yet contains the essential features of canopy architecture that are mainly responsible for observed responses. Thus, this model will not only be a predictive tool but also an educational one. The mathematical setting is the radiative transfer equation in a dense (semiinfinite) canopy. The leaf scattering phase function is assumed to be Lambertian with different reflectance and transmittance. In addition, abaxial and adaxial differentiation is allowed which effectively destroys optical reciprocity. The analytical solution for the canopy BRDF is obtained by manipulation of the integral transport equation (a la Chandrasekhar) for a general LAD. With discretization of the. leaf angle, the resulting set of integral equations are solved iteratively including an acceleration procedure when the single scatter albedo is near one (in the NIR). Results will be compared to the LARS soybean canopy radiances as well as to broadleaf results from a recent Ames experiment.

Trajectory of coronary motion and its significance in robotic motion cancellation.

PubMed

Cattin, Philippe; Dave, Hitendu; Grünenfelder, Jürg; Szekely, Gabor; Turina, Marko; Zünd, Gregor

2004-05-01

To characterize remaining coronary artery motion of beating pig hearts after stabilization with an 'Octopus' using an optical remote analysis technique. Three pigs (40, 60 and 65 kg) underwent full sternotomy after receiving general anesthesia. An 8-bit high speed black and white video camera (50 frames/s) coupled with a laser sensor (60 microm resolution) were used to capture heart wall motion in all three dimensions. Dopamine infusion was used to deliberately modulate cardiac contractility. Synchronized ECG, blood pressure, airway pressure and video data of the region around the first branching point of the left anterior descending (LAD) coronary artery after Octopus stabilization were captured for stretches of 8 s each. Several sequences of the same region were captured over a period of several minutes. Computerized off-line analysis allowed us to perform minute characterization of the heart wall motion. The movement of the points of interest on the LAD ranged from 0.22 to 0.81 mm in the lateral plane (x/y-axis) and 0.5-2.6 mm out of the plane (z-axis). Fast excursions (>50 microm/s in the lateral plane) occurred corresponding to the QRS complex and the T wave; while slow excursion phases (<50 microm/s in the lateral plane) were observed during the P wave and the ST segment. The trajectories of the points of interest during consecutive cardiac cycles as well as during cardiac cycles minutes apart remained comparable (the differences were negligible), provided the hemodynamics remained stable. Inotrope-induced changes in cardiac contractility influenced not only the maximum excursion, but also the shape of the trajectory. Normal positive pressure ventilation displacing the heart in the thoracic cage was evident by the displacement of the reference point of the trajectory. The movement of the coronary artery after stabilization appears to be still significant. Minute characterization of the trajectory of motion could provide the substrate for achieving motion cancellation for existing robotic systems. Velocity plots could also help improve gated cardiac imaging.

Robotic-assisted coronary artery bypass surgery: an 18-year single-centre experience.

PubMed

Giambruno, Vincenzo; Chu, Michael W; Fox, Stephanie; Swinamer, Stuart A; Rayman, Reiza; Markova, Zarina; Barnfield, Rebecca; Cooper, Mitchell; Boyd, Douglas W; Menkis, Alan; Kiaii, Bob

2018-06-01

Minimally invasive robot-assisted direct coronary artery bypass (RADCAB) has emerged as a feasible minimally invasive surgical technique for revascularization that might offer several potential advantages over conventional approaches. We present our 18-year experience in RADCAB. Between February 1998 and February 2016, 605 patients underwent RADCAB. Patients underwent post-procedural selective graft patency assessment using cardiac catheterization. The mortality rate was 0.3%. The rate of conversion to sternotomy for any cause was reduced from 16.0% of the first 200 cases to 6.9% of the last 405 patients. The patency rate of the LITA-to-LAD anastomosis was 97.4%. Surgical re-exploration for bleeding occurred in 1.8% of patients, and the transfusion rate was 9.2%. Average ICU stay was 1.2 ± 1.4 days, and average hospital stay was 4.8 ± 2.9 days. Robot-assisted coronary artery bypass grafting is safe, feasible and it seems to represent an effective alternative to traditional coronary artery bypass grafting in selected patients. Copyright © 2018 John Wiley & Sons, Ltd.

Evaluation and optimization of virtual screening workflows with DEKOIS 2.0--a public library of challenging docking benchmark sets.

PubMed

Bauer, Matthias R; Ibrahim, Tamer M; Vogel, Simon M; Boeckler, Frank M

2013-06-24

The application of molecular benchmarking sets helps to assess the actual performance of virtual screening (VS) workflows. To improve the efficiency of structure-based VS approaches, the selection and optimization of various parameters can be guided by benchmarking. With the DEKOIS 2.0 library, we aim to further extend and complement the collection of publicly available decoy sets. Based on BindingDB bioactivity data, we provide 81 new and structurally diverse benchmark sets for a wide variety of different target classes. To ensure a meaningful selection of ligands, we address several issues that can be found in bioactivity data. We have improved our previously introduced DEKOIS methodology with enhanced physicochemical matching, now including the consideration of molecular charges, as well as a more sophisticated elimination of latent actives in the decoy set (LADS). We evaluate the docking performance of Glide, GOLD, and AutoDock Vina with our data sets and highlight existing challenges for VS tools. All DEKOIS 2.0 benchmark sets will be made accessible at http://www.dekois.com.

A-3 Test Stand

NASA Image and Video Library

2012-06-08

A tethered Stennis Space Center employee climbs an A-3 Test Stand ladded June 8, 2012, against the backdrop of the A-2 and B-1/B-2 stands. The new A-3 Test Stand will enable simulated high-altitude testing of next-generation rocket engines.

Stem cell homing and angiomyogenesis in transplanted hearts are enhanced by combined intramyocardial SDF-1α delivery and endogenous cytokine signaling

PubMed Central

Zhao, Tiemin; Zhang, Dongsheng; Millard, Ronald W.; Ashraf, Muhammad; Wang, Yigang

2009-01-01

We used a heterotopic transplanted working heart model to probe the collaborative role of bone marrow-derived progenitor cells (BPCs) and stromal cell-derived factor (SDF)-1α in attenuating tissue remodeling in recipient and transplanted hearts. BPCs from male transgenic rats expressing green fluorescent protein (GFP+ BPCs, 2 × 106 cells) were injected intravenously into myeloablated female rats. One month later, heterotopic heart transplantation was performed. The left anterior descending coronary artery (LAD) of the recipient heart was occluded permanently. Mesenchymal stem cells (MSCs; 2 × 106 cells) with a null gene (null group) or overexpressing SDF-1α (SDF-1α group) were injected intramyocardially in the LAD perfusion region of both recipient and transplanted hearts. Recipient and transplanted hearts (n = 10 hearts/group) were harvested 21 days later for analysis. The survival of transplanted hearts was assessed daily by palpation in additional animals (n = 7). Five days after LAD occlusion, subpopulations of GFP+ BPCs in the circulation were significantly higher in the SDF-1α group. Y chromosome, 5-bromo-2′-deoxyuridine, Ki67-positive nuclei, newly formed vessels, and GFP+ cells significantly increased in transplanted hearts of the SDF-1α group at 21 days after the injection of MSCs overexpressing SDF-1α, whereas fewer TUNEL-positive nuclei were found. The survival of transplanted hearts was also markedly increased in the SDF-1α group (P < 0.05). Supplementation of endogenous cytokines released from the ischemic myocardium with exogenous MSCs overexpressing SDF-1α significantly increased BPC homing to acutely ischemic recipient and progressively ischemic transplanted hearts. BPC recruitment resulted in the regeneration of new cardiomyocytes and blood vessels and extended survival of the transplanted hearts. PMID:19181961

[Phoneme analysis and phoneme discrimination of juvenile speech therapy school students].

PubMed

Franz, S; Rosanowski, F; Eysholdt, U; Hoppe, U

2011-05-01

Phoneme analysis and phoneme discrimination, important factors in acquiring spoken and written language, have been evaluated in juvenile speech therapy school students. The results have been correlated with the results of a school achievement test. The following questions were of interest: Do students in the lower verbal skill segment show pathological phoneme analysis and phoneme discrimination skills? Do the results of the school achievement test differ from the results by students visiting German "Hauptschule"? How does phoneme analysis and phoneme discrimination performance correlate to other tested parameters? 74 students of a speech therapy school ranging from 7 (th) to 9 (th) grade were examined (ages 12;10-17;04) with the Heidelberg Phoneme Discrimination Test H-LAD and the school achievement test "Prüfsystem für Schul- und Bildungsberatung PSB-R 6-13". Compared to 4 (th) graders the juvenile speech therapy school students showed worse results in the H-LAD test with good differentiation in the lower measuring range. In the PSB-R 6-13 test the examined students did worse compared to students visiting German "Hauptschule" for all grades except 9 (th) grade. Comparing H-LAD and PSB-R 6-13 shows a significant correlation for the sub-tests covering language competence and intelligence but not for the concentration tests. Pathological phoneme analysis and phoneme discrimination skills suggest elevated need for counseling, but this needs to corroborated through additional linguistic parameters and measuring non-verbal intelligence. Further trails are needed in order to clarify whether the results can lead to sophisticated therapy algorithms for educational purposes. © Georg Thieme Verlag KG Stuttgart · New York.

Langmuir Probe Diagnostics of Pulsed Plasma Doping System

NASA Astrophysics Data System (ADS)

Lei, Yu; Overzet, Lawrence J.; Felch, Susan B.; Fang, Ziwei; Koo, Bon-Woong; Goeckner, Matthew J.

2002-10-01

Pulsed plasma doping (P2LAD) is a potential solution to implement ultra-shallow junctions. In this study, Langmuir probe diagnostics techniques were investigated thoroughly for its application to P2LAD system, and the current sensing scheme using batteries and a 'downstairs' load resistor turned out to be the most reliable. Severe limitations of current transformers were found in diagnostics of pulsed plasma. A floating probe was proven to be good at monitoring the disturbances of the Langmuir probe and the cathode voltage. With the above technique, time-resolved Langmuir probe measurements have been carried out in a P2LAD system. The Langmuir probe data in Ar plasma indicate that during a 20 microns long implant pulse the plasma density ranges from 1E9 1E10 cm-3 and the electron temperature ranges from 0.4 to 14 eV. Between the pulses, the density keeps at the high level for 30 ms and then decays exponentially until reaching the range of 3E8 1E9 cm-3, which demonstrates the presence of residual plasma between pulses. A non-zero plasma density during the afterglow is also observed for BF3 plasma. Significant amounts of primary electron and electron beams are present during the ignition and ensuing steady region in both Ar and BF3 plasmas while they are much stronger in BF3 plasma. Plasma density is observed to increase with cathode voltage and pressure while the electron temperature is mainly influenced by the pressure. An overshoot of the cathode voltage during the afterglow region was found, and it significantly influences the plasma potential during the afterglow.

Analysis of myocardial temperature changes in conventional isolated coronary artery bypass grafting.

PubMed

Okamoto, Hiroshi; Tamenishi, Akinori; Nishi, Toshihiko; Niimi, Takao

2014-12-01

To determine whether cold blood cardioplegia (CBCP) can get over coronary artery lesions, we analyzed the relationship between myocardial temperature changes and lesion severity of major coronary arteries. From April 1991 to October 2003, we measured myocardial temperature before and after antegrade and retrograde delivery of CBCP in 492 patients undergoing conventional coronary artery bypass grafting. Stenotic severity of three major coronary arteries was classified into four grades according to preoperative coronary arteriography; grade 0 for 50 % or less, 1 for 75 %, 2 for 90 %, 3 for 99 % or 100 %. We analyzed relationships between myocardial temperature changes [ΔT-A (antegrade) & ΔT-R (retrograde)] and the coronary artery lesion's severity. Average ΔT-A of the right coronary artery had no relationship with stenotic grades. Mean ΔT-A of the left anterior descending (LAD) became less and less in proportion to its stenotic grade [9.7 °C for grade 0, 8.2 °C for grade 1, 7.1 °C for grade 2, and 6.0 °C for grade 3, respectively, (p = 0.0042)]. ΔT-A of the circumflex artery showed similar but weaker tendency than those of LAD. Significant inverse correlations were found between ΔT-A and ΔT-R1 in each territory (p < 0.001). Antegrade delivery was less effective in situations with tight proximal lesion, especially in the LAD territory. Retrograde delivery supplemented antegrade delivery. Myocardial temperature monitoring enables us to deal with inadequate cardioplegic delivery, and is a good indicator of myocardial protection.

Support with intra-aortic balloon pump vs. Impella2.5® and blood flow to the heart, brain and kidneys - an experimental porcine model of ischaemic heart failure.

PubMed

Møller-Helgestad, Ole K; Poulsen, Christian B; Christiansen, Evald H; Lassen, Jens F; Ravn, Hanne B

2015-01-15

Cardiogenic shock as a complication to an acute myocardial infarction has an unacceptably high death rate that has not changed for the last 15years. Mortality is partly related to organ hypoperfusion and mechanical assist devices are used for the most severe cases but we do not know which assist device is the best option. Therefore, we have investigated how an IABP and an Impella®-pump influenced blood flow to the brain, heart and kidneys, in a closed-chest porcine model of severe left ventricular failure. 13 pigs were anesthetised and left ventricular failure was induced by occluding the proximal LAD for 45min followed by 30min of reperfusion. Blood flow was measured in the carotid artery, the LAD, and the renal artery. The Impella® and IABP were inserted via the femoral arteries, and the two devices were tested individually and combined after induction of heart failure. Carotid- (p=0.01) and renal blood flow (p=0.045) were higher on Impella®-support, compared to no support. None of the devices altered the blood flow in the LAD. Cardiac power output (p<0.005) and left ventricular work (p<0.00) were also higher on Impella®-support compared to no support. Haemodynamics and blood flow to the brain and kidneys were significantly better on Impella®-support, suggesting that the Impella® is superior to the IABP in a state of ischaemia induced left ventricular failure. These data, however, needs to be confirmed in a proper clinical trial with patients in cardiogenic shock. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Thoracic spinal cord and cervical vagosympathetic neuromodulation obtund nodose sensory transduction of myocardial ischemia.

PubMed

Salavatian, Siamak; Beaumont, Eric; Gibbons, David; Hammer, Matthew; Hoover, Donald B; Armour, J Andrew; Ardell, Jeffrey L

2017-12-01

Autonomic regulation therapy involving either vagus nerve stimulation (VNS) or spinal cord stimulation (SCS) represents emerging bioelectronic therapies for heart disease. The objective of this study was to determine if VNS and/or SCS modulate primary cardiac afferent sensory transduction of the ischemic myocardium. Using extracellular recordings in 19 anesthetized canines, of 88 neurons evaluated, 36 ventricular-related nodose ganglia sensory neurons were identified by their functional activity responses to epicardial touch, chemical activation of their sensory neurites (epicardial veratridine) and great vessel (descending aorta or inferior vena cava) occlusion. Neural responses to 1min left anterior descending (LAD) coronary artery occlusion (CAO) were then evaluated. These interventions were then studied following either: i) SCS [T1-T3 spinal level; 50Hz, 90% motor threshold] or ii) cervical VNS [15-20Hz; 1.2× threshold]. LAD occlusion activated 66% of identified nodose ventricular sensory neurons (0.33±0.08-0.79±0.20Hz; baseline to CAO; p<0.002). Basal activity of cardiac-related nodose neurons was differentially reduced by VNS (0.31±0.11 to 0.05±0.02Hz; p<0.05) as compared to SCS (0.36±0.12 to 0.28±0.14, p=0.59), with their activity response to transient LAD CAO being suppressed by either SCS (0.85±0.39-0.11±0.04Hz; p<0.03) or VNS (0.75±0.27-0.12±0.05Hz; p<0.04). VNS did not alter evoked neural responses of cardiac-related nodose neurons to great vessel occlusion. Both VNS and SCS obtund ventricular ischemia induced enhancement of nodose afferent neuronal inputs to the medulla. Copyright © 2017 Elsevier B.V. All rights reserved.

Marsh canopy structure changes and the Deepwater Horizon oil spill

USGS Publications Warehouse

Ramsey, Elijah W.; Rangoonwala, Amina; Jones, Cathleen E.

2016-01-01

Marsh canopy structure was mapped yearly from 2009 to 2012 in the Barataria Bay, Louisiana coastal region that was impacted by the 2010 Deepwater Horizon (DWH) oil spill. Based on the previously demonstrated capability of NASA's UAVSAR polarimetric synthetic aperture radar (PolSAR) image data to map Spartina alterniflora marsh canopy structure, structure maps combining the leaf area index (LAI) and leaf angle distribution (LAD, orientation) were constructed for yearly intervals that were directly relatable to the 2010 LAI-LAD classification. The yearly LAI-LAD and LAI difference maps were used to investigate causes for the previously revealed dramatic change in marsh structure from prespill (2009) to postspill (2010, spill cessation), and the occurrence of structure features that exhibited abnormal spatial and temporal patterns. Water level and salinity records showed that freshwater releases used to keep the oil offshore did not cause the rapid growth from 2009 to 2010 in marsh surrounding the inner Bay. Photointerpretation of optical image data determined that interior marsh patches exhibiting rapid change were caused by burns and burn recovery, and that the pattern of 2010 to 2011 LAI decreases in backshore marsh and extending along some tidal channels into the interior marsh were not associated with burns. Instead, the majority of 2010 to 2011 shoreline features aligned with vectors displaying the severity of 2010 shoreline oiling from the DWH spill. Although the association is not conclusive of a causal oil impact, the coexistent pattern is a significant discovery. PolSAR marsh structure mapping provided a unique perspective of marsh biophysical status that enhanced detection of change and monitoring of trends important to management effectiveness.

Dodecafluoropentane emulsion elicits cardiac protection against myocardial infarction through an ATP-Sensitive K+ channel dependent mechanism.

PubMed

Strom, Joshua; Swyers, Trevor; Wilson, David; Unger, Evan; Chen, Qin M; Larson, Douglas F

2014-12-01

Dodecafluoropentane emulsion (DDFPe) is a perfluorocarbon with high oxygen dissolving, transport, and delivery capacity that may offer the potential to limit ischemic injury prior to clinical reperfusion. Here we investigated the cardiac protective potential of DDFPe in a mouse model of myocardial infarction. Myocardial infarction was initiated by permanent ligation of the left anterior descending (LAD) coronary artery. Mice were administered vehicle or 5-hydroxydecanoate (5-HD) intravenously 10 min before LAD occlusion followed by a single intravenous administration of vehicle or DDFPe immediately after occlusion. Heart tissue and serum samples were collected 24 after LAD occlusion for measurement of infarct size and cardiac troponin I (cTnI) levels, respectively. DDFPe treatment reduced infarct size by approximately 72% (36.9 ± 4.2% for vehicle vs 10.4 ± 2.3% for DDFPe; p < 0.01; n = 6-8) at 24 h. Serum cTnI levels were similarly reduced by DDFPe (35.0 ± 4.6 ng/ml for vehicle vs 15.8 ± 1.6 ng/ml for DDFPe; p < 0.01; n = 6-8). Pretreatment with 5-HD, a mitochondrial ATP-sensitive potassium channel (mitoK(ATP)) inhibitor, blocked the reduction in infarct size (29.2 ± 4.4% for 5-HD vs 35.4 ± 7.4% for 5-HD+DDFPe; p = 0.48; n = 6-8) and serum cTnI levels (27.4 ± 5.1 ng/ml for 5-HD vs 34.6 ± 5.3 ng/ml for 5-HD+DDFPe; p = 0.86; n = 6-8) by DDFPe. Our data indicate a cardiac protective role of DDFPe that persists beyond its retention time in the body and is dependent on mitoK(ATP), an important mediator of ischemic preconditioning induced cardiac protection.

Global modeling of land water and energy balances. Part III: Interannual variability

USGS Publications Warehouse

Shmakin, A.B.; Milly, P.C.D.; Dunne, K.A.

2002-01-01

The Land Dynamics (LaD) model is tested by comparison with observations of interannual variations in discharge from 44 large river basins for which relatively accurate time series of monthly precipitation (a primary model input) have recently been computed. When results are pooled across all basins, the model explains 67% of the interannual variance of annual runoff ratio anomalies (i.e., anomalies of annual discharge volume, normalized by long-term mean precipitation volume). The new estimates of basin precipitation appear to offer an improvement over those from a state-of-the-art analysis of global precipitation (the Climate Prediction Center Merged Analysis of Precipitation, CMAP), judging from comparisons of parallel model runs and of analyses of precipitation-discharge correlations. When the new precipitation estimates are used, the performance of the LaD model is comparable to, but not significantly better than, that of a simple, semiempirical water-balance relation that uses only annual totals of surface net radiation and precipitation. This implies that the LaD simulations of interannual runoff variability do not benefit substantially from information on geographical variability of land parameters or seasonal structure of interannual variability of precipitation. The aforementioned analyses necessitated the development of a method for downscaling of long-term monthly precipitation data to the relatively short timescales necessary for running the model. The method merges the long-term data with a reference dataset of 1-yr duration, having high temporal resolution. The success of the method, for the model and data considered here, was demonstrated in a series of model-model comparisons and in the comparisons of modeled and observed interannual variations of basin discharge.

Global longitudinal strain in patients with suspected heart failure and a normal ejection fraction: does it improve diagnosis and risk stratification?

PubMed

Pellicori, Pierpaolo; Kallvikbacka-Bennett, Anna; Khaleva, Olga; Carubelli, Valentina; Costanzo, Pierluigi; Castiello, Teresa; Wong, Kenneth; Zhang, Jufen; Cleland, John G F; Clark, Andrew L

2014-01-01

Many patients have clinical, structural or bio-marker evidence of heart failure (HF) but a normal left ventricular ejection fraction (LVEF; HeFNEF). Measurement of global longitudinal strain (GLS) may add diagnostic and prognostic information. Patients with symptoms suggesting heart failure and LVEF ≥50% were studied: 76 had no substantial cardiac dysfunction (left atrial diameter (LAD) <40 mm and amino-terminal pro-brain natriuretic peptide (NTproBNP) <400 ng/l); 99 had "possible HeFNEF" (LAD ≥40 mm or NTproBNP ≥400 ng/l); and 138 had "definite HeFNEF" (LAD ≥40 mm and NTproBNP ≥400 ng/L). Mean LVEF was 58% in each subgroup. Patients with definite HeFNEF were older, more likely to have atrial fibrillation, had more symptoms and signs of fluid retention, were more likely to have right ventricular dysfunction and had higher pulmonary pressures than other groups. Mean GLS (SD) was less negative in patients with definite HeFNEF (-13.6 (3.0)% vs. possible HeFNEF: -15.2 (3.1)% vs. no substantial cardiac dysfunction: -15.9 (2.4)%; p < 0.001). GLS was -19.1 (2.1)% in 20 controls. During a median follow up of 647 days, cardiovascular death or an unplanned hospitalisation for heart failure occurred in 62 patients. In univariable analysis, GLS but not LVEF predicted events. However, in a multi-variable analysis, only urea, NTproBNP, left atrial volume, inferior vena cava diameter and atrial fibrillation independently predicted adverse outcome. GLS is abnormal in patients who have other evidence of HeFNEF, is associated with a worse prognosis in this population but is not a powerful independent predictor of outcome.

Signaling through the Phosphatidylinositol 3-Kinase (PI3K)/Mammalian Target of Rapamycin (mTOR) Axis Is Responsible for Aerobic Glycolysis mediated by Glucose Transporter in Epidermal Growth Factor Receptor (EGFR)-mutated Lung Adenocarcinoma.

PubMed

Makinoshima, Hideki; Takita, Masahiro; Saruwatari, Koichi; Umemura, Shigeki; Obata, Yuuki; Ishii, Genichiro; Matsumoto, Shingo; Sugiyama, Eri; Ochiai, Atsushi; Abe, Ryo; Goto, Koichi; Esumi, Hiroyasu; Tsuchihara, Katsuya

2015-07-10

Oncogenic epidermal growth factor receptor (EGFR) signaling plays an important role in regulating global metabolic pathways, including aerobic glycolysis, the pentose phosphate pathway (PPP), and pyrimidine biosynthesis. However, the molecular mechanism by which EGFR signaling regulates cancer cell metabolism is still unclear. To elucidate how EGFR signaling is linked to metabolic activity, we investigated the involvement of the RAS/MEK/ERK and PI3K/AKT/mammalian target of rapamycin (mTOR) pathways on metabolic alteration in lung adenocarcinoma (LAD) cell lines with activating EGFR mutations. Although MEK inhibition did not alter lactate production and the extracellular acidification rate, PI3K/mTOR inhibitors significantly suppressed glycolysis in EGFR-mutant LAD cells. Moreover, a comprehensive metabolomics analysis revealed that the levels of glucose 6-phosphate and 6-phosphogluconate as early metabolites in glycolysis and PPP were decreased after inhibition of the PI3K/AKT/mTOR pathway, suggesting a link between PI3K signaling and the proper function of glucose transporters or hexokinases in glycolysis. Indeed, PI3K/mTOR inhibition effectively suppressed membrane localization of facilitative glucose transporter 1 (GLUT1), which, instead, accumulated in the cytoplasm. Finally, aerobic glycolysis and cell proliferation were down-regulated when GLUT1 gene expression was suppressed by RNAi. Taken together, these results suggest that PI3K/AKT/mTOR signaling is indispensable for the regulation of aerobic glycolysis in EGFR-mutated LAD cells. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

TU-G-204-01: BEST IN PHYSICS (IMAGING): Dynamic CT Myocardial Perfusion Measurement and Its Comparison to Fractional Flow Reserve

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

Ziemer, B; Hubbard, L; Groves, E

2015-06-15

Purpose: To evaluate a first pass analysis (FPA) technique for CT perfusion measurement in a swine animal and its validation using fractional flow reserve (FFR) as a reference standard. Methods: Swine were placed under anesthesia and relevant physiologic parameters were continuously recorded. Intra-coronary adenosine was administered to induce maximum hyperemia. A pressure wire was advanced distal to the first diagonal branch of the left anterior descending (LAD) artery for FFR measurements and a balloon dilation catheter was inserted over the pressure wire into the proximal LAD to create varying levels of stenosis. Images were acquired with a 320-row wide volumemore » CT scanner. Three main coronary perfusion beds were delineated in the myocardium using arteries extracted from CT angiography images using a minimum energy hypothesis. The integrated density in the perfusion bed was used to calculate perfusion using the FPA technique. The perfusion in the LAD bed over a range of stenosis severity was measured. The measured fractional perfusion was compared to FFR and linear regression was performed. Results: The measured fractional perfusion using the FPA technique (P-FPA) and FFR were related as P-FPA = 1.06FFR – 0.06 (r{sup 2} = 0.86). The perfusion measurements were calculated with only three to five total CT volume scans, which drastically reduces the radiation dose as compared with the existing techniques requiring 15–20 volume scans. Conclusion: The measured perfusion using the first pass analysis technique showed good correlation with FFR measurements as a reference standard. The technique for perfusion measurement can potentially make a substantial reduction in radiation dose as compared with the existing techniques.« less

Cardiac Dose Reduction with Deep-Inspiratory Breath Hold Technique of Radiotherapy for Left-Sided Breast Cancer.

PubMed

Sripathi, Lalitha Kameshwari; Ahlawat, Parveen; Simson, David K; Khadanga, Chira Ranjan; Kamarsu, Lakshmipathi; Surana, Shital Kumar; Arasu, Kavi; Singh, Harpreet

2017-01-01

Different techniques of radiation therapy have been studied to reduce the cardiac dose in left breast cancer. In this prospective dosimetric study, the doses to heart as well as other organs at risk (OAR) were compared between free-breathing (FB) and deep inspiratory breath hold (DIBH) techniques in intensity modulated radiotherapy (IMRT) and opposed-tangent three-dimensional radiotherapy (3DCRT) plans. Fifteen patients with left-sided breast cancer underwent computed tomography simulation and images were obtained in both FB and DIBH. Radiotherapy plans were generated with 3DCRT and IMRT techniques in FB and DIBH images in each patient. Target coverage, conformity index, homogeneity index, and mean dose to heart (Heart D mean ), left lung, left anterior descending artery (LAD) and right breast were compared between the four plans using the Wilcoxon signed rank test. Target coverage was adequate with both 3DCRT and IMRT plans, but IMRT plans showed better conformity and homogeneity. A statistically significant dose reduction of all OARs was found with DIBH. 3DCRT DIBH decreased the Heart D mean by 53.5% (7.1 vs. 3.3 Gy) and mean dose to LAD by 28% compared to 3DCRT FB . IMRT further lowered mean LAD dose by 18%. Heart D mean was lower with 3DCRT DIBH over IMRT DIBH (3.3 vs. 10.2 Gy). Mean dose to the contralateral breast was also lower with 3DCRT over IMRT (0.32 vs. 3.35 Gy). Mean dose and the V 20 of ipsilateral lung were lower with 3DCRT DIBH over IMRT DIBH (13.78 vs. 18.9 Gy) and (25.16 vs. 32.95%), respectively. 3DCRT DIBH provided excellent dosimetric results in patients with left-sided breast cancer without the need for IMRT.

Cardiac Dose Reduction with Deep-Inspiratory Breath Hold Technique of Radiotherapy for Left-Sided Breast Cancer

PubMed Central

Sripathi, Lalitha Kameshwari; Ahlawat, Parveen; Simson, David K; Khadanga, Chira Ranjan; Kamarsu, Lakshmipathi; Surana, Shital Kumar; Arasu, Kavi; Singh, Harpreet

2017-01-01

Introduction: Different techniques of radiation therapy have been studied to reduce the cardiac dose in left breast cancer. Aim: In this prospective dosimetric study, the doses to heart as well as other organs at risk (OAR) were compared between free-breathing (FB) and deep inspiratory breath hold (DIBH) techniques in intensity modulated radiotherapy (IMRT) and opposed-tangent three-dimensional radiotherapy (3DCRT) plans. Materials and Methods: Fifteen patients with left-sided breast cancer underwent computed tomography simulation and images were obtained in both FB and DIBH. Radiotherapy plans were generated with 3DCRT and IMRT techniques in FB and DIBH images in each patient. Target coverage, conformity index, homogeneity index, and mean dose to heart (Heart Dmean), left lung, left anterior descending artery (LAD) and right breast were compared between the four plans using the Wilcoxon signed rank test. Results: Target coverage was adequate with both 3DCRT and IMRT plans, but IMRT plans showed better conformity and homogeneity. A statistically significant dose reduction of all OARs was found with DIBH. 3DCRTDIBH decreased the Heart Dmean by 53.5% (7.1 vs. 3.3 Gy) and mean dose to LAD by 28% compared to 3DCRTFB. IMRT further lowered mean LAD dose by 18%. Heart Dmean was lower with 3DCRTDIBH over IMRTDIBH (3.3 vs. 10.2 Gy). Mean dose to the contralateral breast was also lower with 3DCRT over IMRT (0.32 vs. 3.35 Gy). Mean dose and the V20 of ipsilateral lung were lower with 3DCRTDIBH over IMRTDIBH (13.78 vs. 18.9 Gy) and (25.16 vs. 32.95%), respectively. Conclusions: 3DCRTDIBH provided excellent dosimetric results in patients with left-sided breast cancer without the need for IMRT. PMID:28974856

The continuum spectral characteristics of gamma ray bursts observed by BATSE

NASA Technical Reports Server (NTRS)

Pendleton, Geoffrey N.; Paciesas, William S.; Briggs, Michael S.; Mallozzi, Robert S.; Koshut, Tom M.; Fishman, Gerald J.; Meegan, Charles A.; Wilson, Robert B.; Harmon, Alan B.; Kouveliotou, Chryssa

1994-01-01

Distributions of the continuum spectral characteristics of 260 bursts in the first Burst and Transient Source Experiment (BATSE) catalog are presented. The data are derived from flux ratios calculated from the BATSE Large Area Detector (LAD) four channel discriminator data. The data are converted from counts to photons using a direct spectral inversion technique to remove the effects of atmospheric scattering and the energy dependence of the detector angular response. Although there are intriguing clusterings of bursts in the spectral hardness ratio distributions, no evidence for the presence of distinct burst classes based on spectral hardness ratios alone is found. All subsets of bursts selected for their spectral characteristics in this analysis exhibit spatial distributions consistent with isotropy. The spectral diversity of the burst population appears to be caused largely by the highly variable nature of the burst production mechanisms themselves.

Ultrasound imaging of propagation of myocardial contraction for non-invasive identification of myocardial ischemia

NASA Astrophysics Data System (ADS)

Matsuno, Yuya; Taki, Hirofumi; Yamamoto, Hiroaki; Hirano, Michinori; Morosawa, Susumu; Shimokawa, Hiroaki; Kanai, Hiroshi

2017-07-01

Non-invasive identification of ischemic regions is important for diagnosis and treatment of myocardial infarction. In the present study, ultrasound measurement was applied to the interventricular septum of three open-chest swine hearts. The properties of the myocardial contraction response of the septum were compared between normal and acute ischemic conditions, where the acute ischemic condition of the septum originated from direct avascularization of the left anterior descending (LAD) coronary artery. The result showed that the contraction response propagated from the basal side to the apical side along the septum. The estimated propagation velocities in the normal and acute ischemic conditions were 3.6 and 1.9 m/s, respectively. This finding indicates that acute ischemia which occurred 5 s after the avascularization of the LAD promptly suppressed the propagation velocity through the ventricular septum to about half the normal velocity. It was suggested that the myocardial ischemic region could be identified using the difference in the propagation velocity of the myocardial response to contraction.

Spontaneous coronary artery dissection as a cause of myocardial infarction

PubMed Central

Aksakal, Aytekin; Arslan, Uğur; Yaman, Mehmet; Urumdaş, Mehmet; Ateş, Ahmet Hakan

2014-01-01

Spontaneous coronary artery dissection (SCAD) is a rare disease that is usually seen in young women in left descending coronary artery and result in events like sudden cardiac death and acute myocardial infarction. A 70-year-old man was admitted to the emergency department with chest pain which started 1 h ago during a relative’s funeral. The initial electrocardiography demonstrated 2 mm ST-segment depression in leads V1-V3 and the patient underwent emergent coronary angiography. SCAD simultaneously in two different coronary arteries [left anterior descending (LAD) artery and left circumflex (LCx)] artery was detected and SCAD in LCx artery was causing total occlusion which resulted in acute myocardial infarction. Successful stenting was performed thereafter for both lesions. In addition to the existence of SCAD simultaneously in two different coronary arteries, the presence of muscular bridge and SCAD together at the same site of the LAD artery was another interesting point which made us report this case. PMID:25548620

CORRELATES BETWEEN HUMAN LUNG INJURY AFTER PARTICLE EXPOSURE AND RECURRENT AIRWAY OBSTRUCTION IN THE HORSE

EPA Science Inventory

Characteristics of the clinical presentation, physiologic changes, and pathology of the human response to particulate matter (PM) are comparable to inflammatory airway disease (lAD) and recurrent airway obstruction (RAO)lheaves in the horse. Both present with symptoms of cough,...

Studies in First and Second Language Acquisition.

ERIC Educational Resources Information Center

Eckman, Fred R., Ed.; Hastings, Ashley J., Ed.

Papers presented at a 1977 symposium on language acquisition held at the University of Wisconsin/Milwaukee are included. Contents are as follows: "Assumptions, Methods and Goals in Language Acquisition Research" (Sheldon); "The Mother as LAD: Interaction between Order and Frequency of Parental Input and Child Production"…

An investigation of correlation between left coronary bifurcation angle and hemodynamic changes in coronary stenosis by coronary computed tomography angiography-derived computational fluid dynamics

PubMed Central

Chaichana, Thanapong

2017-01-01

Background To investigate the correlation between left coronary bifurcation angle and coronary stenosis as assessed by coronary computed tomography angiography (CCTA)-generated computational fluid dynamics (CFD) analysis when compared to the CCTA analysis of coronary lumen stenosis and plaque lesion length with invasive coronary angiography (ICA) as the reference method. Methods Thirty patients (22 males, mean age: 59±6.9 years) with calcified plaques at the left coronary artery were included in the study with all patients undergoing CCTA and ICA examinations. CFD simulation was performed to analyze hemodynamic changes to the left coronary artery models in terms of wall shear stress, wall pressure and flow velocity, with findings correlated to the coronary stenosis and degree of bifurcation angle. Calcified plaque length was measured in the left coronary artery with diagnostic value compared to that from coronary lumen and bifurcation angle assessments. Results Of 26 significant stenosis at left anterior descending (LAD) and 13 at left circumflex (LCx) on CCTA, only 14 and 5 of them were confirmed to be >50% stenosis at LAD and LCx respectively on ICA, resulting in sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 100%, 52%, 49% and 100%. The mean plaque length was measured 5.3±3.6 and 4.4±1.9 mm at LAD and LCx, respectively, with diagnostic sensitivity, specificity, PPV and NPV being 92.8%, 46.7%, 61.9% and 87.5% for extensively calcified plaques. The mean bifurcation angle was measured 83.9±13.6º and 83.8±13.3º on CCTA and ICA, respectively, with no significant difference (P=0.98). The corresponding sensitivity, specificity, PPV and NPV were 100%, 78.6%, 84.2% and 100% based on bifurcation angle measurement on CCTA, 100%, 73.3%, 78.9% and 100% based on bifurcation angle measurements on ICA, respectively. Wall shear stress was noted to increase in the LAD and LCx models with significant stenosis and wider angulation (>80º), but demonstrated little or no change in most of the coronary models with no significant stenosis and narrower angulation (<80º). Conclusions This study further clarifies the relationship between left coronary bifurcation angle and significant stenosis, with angulation measurement serving as a more accurate approach than coronary lumen assessment or plaque lesion length for determining significant coronary stenosis. Left coronary bifurcation angle is suggested to be incorporated into coronary artery disease (CAD) assessment when diagnosing significant CAD. PMID:29184766

Value of Combining Left Atrial Diameter and Amino-terminal Pro-brain Natriuretic Peptide to the CHA2DS2-VASc Score for Predicting Stroke and Death in Patients with Sick Sinus Syndrome after Pacemaker Implantation.

PubMed

Mo, Bin-Feng; Lu, Qiu-Fen; Lu, Shang-Biao; Xie, Yu-Quan; Feng, Xiang-Fei; Li, Yi-Gang

2017-08-20

The CHA2DS2-VASc score is used clinically for stroke risk stratification in patients with atrial fibrillation (AF). We sought to investigate whether the CHA2DS2-VASc score predicts stroke and death in Chinese patients with sick sinus syndrome (SSS) after pacemaker implantation and to evaluate whether the predictive power of the CHA2DS2-VASc score could be improved by combining it with left atrial diameter (LAD) and amino-terminal pro-brain natriuretic peptide (NT-proBNP). A total of 481 consecutive patients with SSS who underwent pacemaker implantation from January 2004 to December 2014 in our department were included. The CHA2DS2-VASc scores were retrospectively calculated according to the hospital medical records before pacemaker implantation. The outcome data (stroke and death) were collected by pacemaker follow-up visits and telephonic follow-up until December 31, 2015. During 2151 person-years of follow-up, 46 patients (9.6%) suffered stroke and 52 (10.8%) died. The CHA2DS2-VASc score showed a significant association with the development of stroke (hazard ratio [HR] 1.45, 95% confidence interval [CI] 1.20-1.75, P< 0.001) and death (HR 1.45, 95% CI 1.22-1.71, P< 0.001). The combination of increased LAD and the CHA2DS2-VASc score improved the predictive power for stroke (C-stat 0.69, 95% CI 0.61-0.77 vs. C-stat 0.66, 95% CI 0.57-0.74, P= 0.013), and the combination of increased NT-proBNP and the CHA2DS2-VASc score improved the predictive power for death (C-stat 0.70, 95% CI 0.64-0.77 vs. C-stat 0.67, 95% CI 0.60--0.75, P= 0.023). CHA2DS2-VASc score is valuable for predicting stroke and death risk in patients with SSS after pacemaker implantation. The addition of LAD and NT-proBNP to the CHA2DS2-VASc score improved its predictive power for stroke and death, respectively, in this patient cohort. Future prospective studies are warranted to validate the benefit of adding LAD and NT-proBNP to the CHA2DS2-VASc score for predicting stroke and death risk in non-AF populations.

New Century, New Identities: Building on a Typology of Nonheterosexual College Men

ERIC Educational Resources Information Center

Dilley, Patrick

2010-01-01

Drawing on recent ethnographic studies of nonheterosexual youth, nonheterosexual identity development, and online collegiate identity management, this article outlines an extension of prior typological work concerning nonheterosexual male college students proposed by the author. Two new types ("Twitter Twinks" and "Lads Without Labels") are…

ELECTROLYTIC SEPARATION PROCESS AND APPARATUS

DOEpatents

McLain, M.E. Jr.; Roberts, M.W.

1962-03-01

A method is given for dissolving stainless steel-c lad fuel elements in dilute acids such as half normal sulfuric acid. The fuel element is made the anode in a Y-shaped electrolytic cell which has a flowing mercury cathode; the stainless steel elements are entrained in the mercury and stripped therefrom by a continuous process. (AEC)

Measuring the Determinants of Relative Economic Performance of Rural Areas

ERIC Educational Resources Information Center

Agarwal, Sheela; Rahman, Sanzidur; Errington, Andrew

2009-01-01

This paper examines the determinants of economic performance of 149 English rural Local Authority Districts (LADs). A Three Stage Least Square (3SLS) estimation procedure was employed to jointly determine the influence of a wide range of indicators representing economic, human, cultural and environmental capital, as well as less tangible or…

Ordinary Least Squares and Quantile Regression: An Inquiry-Based Learning Approach to a Comparison of Regression Methods

ERIC Educational Resources Information Center

Helmreich, James E.; Krog, K. Peter

2018-01-01

We present a short, inquiry-based learning course on concepts and methods underlying ordinary least squares (OLS), least absolute deviation (LAD), and quantile regression (QR). Students investigate squared, absolute, and weighted absolute distance functions (metrics) as location measures. Using differential calculus and properties of convex…

Previously misdiagnosed linear IgA dermatosis resolved with dapsone.

PubMed

Tieppo Francio, Vinicius; Towery, Chris; Davani, Saeid; Allen, Travis; Brown, Tony L

2018-04-25

This is the case of a 25-year-old African American woman with a 3-week history of itching with burning, blistering lesions on her torso and extremities. Medical history was unremarkable. Medical treatments included three visits to urgent care, where she was treated with antivirals, oral and topical steroids, antibiotics and antifungals unsuccessfully. We performed a skin biopsy, and immunoflorescent studies revealed a linear deposition of IgA antigen at the basement membrane. The clinical diagnosis of linear IgA dermatosis (LAD) was established, with no eliciting cause, other than potential occupational exposure to Chlamydophila psittaci via her employment in a pet store. This is the first case to our knowledge to report such an association. However, confirmation of the exposure would only establish correlation, not causality. Resolution of symptoms and blisters was achieved with dapsone treatment. Accordingly, we highlight the crucial importance of reviewing exposures, along with the potential aetiology of LAD. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Coronary artery to pulmonary artery fistula.

PubMed

Dadkhah-Tirani, Heidar; Salari, Arsalan; Shafighnia, Shora; Hosseini, Seyed Fazel; Naghdipoor, Misa

2013-01-01

Male, 69 FINAL DIAGNOSIS: Coronary artery to pulmonary artery fistula Symptoms: Chest pain Medication: - Clinical Procedure: Echocardiography • angiography • surgical intervention Specialty: Cardiology • Cardiac Surgery. Rare disease. A coronary artery fistula is an abnormal communication between a coronary artery and one of the cardiac chambers or a great vessel, so bypassing the myocardial capillary network. They are usually discovered incidentally upon coronary angiography. Clinical manifestations are variable depending on the type of fistula, the severity of shunt, site of shunt, and presence of other cardiac condition. We report a 69-year-old man without any previous medical history, who was admitted to our hospital with chest pain. The electrocardiogram (ECG) showed a sinus rhythm with ST depression in V2 to V6 precordial leads. Coronary angiography revealed a coronary artery fistula from left anterior descending coronary artery (LAD) to the main pulmonary artery, right coronary artery blockage and significant stenoses on the LAD and left circumflex artery (LCX). Surgical treatment was chosen because of the total occlusion of the right coronary artery and to relieve of pain to improve quality of life.

Coronary angioscopy: a monorail angioscope with movable guide wire.

PubMed

Nanto, S; Ohara, T; Mishima, M; Hirayama, A; Komamura, K; Matsumura, Y; Kodama, K

1991-03-01

A new angioscope was devised for easier visualization of the coronary artery. In its tip, the angioscope (Olympus) with an outer diameter of 0.8 mm had a metal lumen, through which a 0.014-in steerable guide wire passed. Using a 8F guiding catheter and a guide wire, it was introduced into the distal coronary artery. With injection of warmed saline through the guiding catheter, the coronary segments were visualized. In the attempted 70 vessels (32 left anterior descending [LAD], 10 right coronary [RCA], 28 left circumflex [LCX]) from 48 patients, 60 vessels (86%) were successfully examined. Twenty-two patients who underwent attempted examination of both LAD and LCX; both coronary arteries were visualized in 19 patients (86%). In the proximal site of the lesion, 40 patients have the diagonal branch or the obtuse marginal branch. In 34 patients (85%) the angioscope was inserted beyond these branches. In 12 very tortuous vessels, eight vessels (67%) were examined. In conclusion, the new monorail coronary angioscope with movable guide wire is useful to examine the stenotic lesions of the coronary artery.

The LOFT perspective on neutron star thermonuclear bursts: White paper in support of the mission concept of the large observatory for X-ray timing

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

in't Zand, J. J.M.; Malone, Christopher M.; Altamirano, D.

2015-01-14

The Large Area Detector (LAD) on the Large Observatory For X-ray Timing ( LOFT ), with a 8.5 m 2 photon- collecting area in the 2–30 keV bandpass at CCD-class spectral resolving power (λ/Δλ = 10 – 100), is designed for optimum performance on bright X-ray sources. Thus, it is well-suited to study thermonuclear X-ray bursts from Galactic neutron stars. These bursts will typically yield 2 x 10 5 photon detections per second in the LAD, which is at least 15 times more than with any other instrument past, current or anticipated. The Wide Field Monitor (WFM) foreseen for LOFTmore » uniquely combines 2–50 keV imaging with large (30%) prompt sky coverage. This will enable the detection of tens of thousands of thermonuclear X-ray bursts during a 3-yr mission, including tens of superbursts. Both numbers are similar or more than the current database gathered in 50 years of X-ray astronomy.« less

Research on Liquid Management Technology in Water Tank and Reactor for Propulsion System with Hydrogen Production System Utilizing Aluminum and Water Reaction

NASA Astrophysics Data System (ADS)

Imai, Ryoji; Imamura, Takuya; Sugioka, Masatoshi; Higashino, Kazuyuki

2017-12-01

High pressure hydrogen produced by aluminum and water reaction is considered to be applied to space propulsion system. Water tank and hydrogen production reactor in this propulsion system require gas and liquid separation function under microgravity condition. We consider to install vane type liquid acquisition device (LAD) utilizing surface tension in the water tank, and install gas-liquid separation mechanism by centrifugal force which swirling flow creates in the hydrogen reactor. In water tank, hydrophilic coating was covered on both tank wall and vane surface to improve wettability. Function of LAD in water tank and gas-liquid separation in reaction vessel were evaluated by short duration microgravity experiments using drop tower facility. In the water tank, it was confirmed that liquid was driven and acquired on the outlet due to capillary force created by vanes. In addition of this, it was found that gas-liquid separation worked well by swirling flow in hydrogen production reactor. However, collection of hydrogen gas bubble was sometimes suppressed by aluminum alloy particles, which is open problem to be solved.

Quantification of coronary microvascular resistance using angiographic images for volumetric blood flow measurement: in vivo validation

PubMed Central

Zhang, Zhang; Takarada, Shigeho

2011-01-01

Structural coronary microcirculation abnormalities are important prognostic determinants in clinical settings. However, an assessment of microvascular resistance (MR) requires a velocity wire. A first-pass distribution analysis technique to measure volumetric blood flow has been previously validated. The aim of this study was the in vivo validation of the MR measurement technique using first-pass distribution analysis. Twelve anesthetized swine were instrumented with a transit-time ultrasound flow probe on the proximal segment of the left anterior descending coronary artery (LAD). Microspheres were injected into the LAD to create a model of microvascular dysfunction. Adenosine (400 μg·kg−1·min−1) was used to produce maximum hyperemia. A region of interest in the LAD arterial bed was drawn to generate time-density curves using angiographic images. Volumetric blood flow measurements (Qa) were made using a time-density curve and the assumption that blood was momentarily replaced with contrast agent during the injection. Blood flow from the flow probe (Qp), coronary pressure (Pa), and right atrium pressure (Pv) were continuously recorded. Flow probe-based normalized MR (NMRp) and angiography-based normalized MR (NMRa) were calculated using Qp and Qa, respectively. In 258 measurements, Qa showed a strong correlation with the gold standard Qp (Qa = 0.90 Qp + 6.6 ml/min, r2 = 0.91, P < 0.0001). NMRa correlated linearly with NMRp (NMRa = 0.90 NMRp + 0.02 mmHg·ml−1·min−1, r2 = 0.91, P < 0.0001). Additionally, the Bland-Altman analysis showed a close agreement between NMRa and NMRp. In conclusion, a technique based on angiographic image data for quantifying NMR was validated using a swine model. This study provides a method to measure NMR without using a velocity wire, which can potentially be used to evaluate microvascular conditions during coronary arteriography. PMID:21398596

Topologically associating domains are stable units of replication-timing regulation.

PubMed

Pope, Benjamin D; Ryba, Tyrone; Dileep, Vishnu; Yue, Feng; Wu, Weisheng; Denas, Olgert; Vera, Daniel L; Wang, Yanli; Hansen, R Scott; Canfield, Theresa K; Thurman, Robert E; Cheng, Yong; Gülsoy, Günhan; Dennis, Jonathan H; Snyder, Michael P; Stamatoyannopoulos, John A; Taylor, James; Hardison, Ross C; Kahveci, Tamer; Ren, Bing; Gilbert, David M

2014-11-20

Eukaryotic chromosomes replicate in a temporal order known as the replication-timing program. In mammals, replication timing is cell-type-specific with at least half the genome switching replication timing during development, primarily in units of 400-800 kilobases ('replication domains'), whose positions are preserved in different cell types, conserved between species, and appear to confine long-range effects of chromosome rearrangements. Early and late replication correlate, respectively, with open and closed three-dimensional chromatin compartments identified by high-resolution chromosome conformation capture (Hi-C), and, to a lesser extent, late replication correlates with lamina-associated domains (LADs). Recent Hi-C mapping has unveiled substructure within chromatin compartments called topologically associating domains (TADs) that are largely conserved in their positions between cell types and are similar in size to replication domains. However, TADs can be further sub-stratified into smaller domains, challenging the significance of structures at any particular scale. Moreover, attempts to reconcile TADs and LADs to replication-timing data have not revealed a common, underlying domain structure. Here we localize boundaries of replication domains to the early-replicating border of replication-timing transitions and map their positions in 18 human and 13 mouse cell types. We demonstrate that, collectively, replication domain boundaries share a near one-to-one correlation with TAD boundaries, whereas within a cell type, adjacent TADs that replicate at similar times obscure replication domain boundaries, largely accounting for the previously reported lack of alignment. Moreover, cell-type-specific replication timing of TADs partitions the genome into two large-scale sub-nuclear compartments revealing that replication-timing transitions are indistinguishable from late-replicating regions in chromatin composition and lamina association and accounting for the reduced correlation of replication timing to LADs and heterochromatin. Our results reconcile cell-type-specific sub-nuclear compartmentalization and replication timing with developmentally stable structural domains and offer a unified model for large-scale chromosome structure and function.

[Incidence, associated factors, and follow-up of hospital heart failure complicating acute anterior myocardial infarction successfully treated by primary angioplasty].

PubMed

Meimoun, P; M'barek, D; Dragomir, C; Luycx-Bore, A; Elmkies, F; Boulanger, J; Zemir, H; Martis, S; Neykova, A; Tzvetkov, B; Clerc, J

2013-11-01

Heart failure (HF) complicating acute myocardial infarction (AMI) is of poor prognosis and is often associated with patient's characteristics and success of reperfusion strategies. However, few data is available regarding the high-risk subgroup of patients with anterior AMI treated successfully by primary angioplasty. The aim of the study was to assess the incidence, associated factors, and the future of HF occurring during hospitalisation, in the setting of anterior AMI treated successfully by primary angioplasty. Eighty-five consecutive patients with anterior AMI treated successfully by primary angioplasty (final angiographic TIMI flow grade=3, without residual stenosis) were included. Clinical, biochemical, angiographic, and echocardiographic data were prospectively collected and compared between patients with (Killip 2 and 3) and without HF during hospitalisation. Fifteen patients had HF (18%) during hospitalisation and 70 did not. By comparison to patients without HF, patients with HF were more frequently diabetics, had troponin peak and CPK, leucocytes count, and fasting glucose higher, LVEF and wall motion score index in the left anterior descending territory (WMSi-lad) poorer, and a lower non-invasive coronary flow reserve (CFR) in the LAD 24hours after angioplasty (all, P<0.05). In multivariate analysis, fasting glucose, leucocytes count after angioplasty, CFR and WMSi-lad were independently associated with HF, even after adjusting with angiographic variables (all, P<0.05). At 6months, patients with HF had less recovery of LV function and higher frequency of adverse LV remodelling (58% versus 20%, P<0.01) by comparison to patients without HF. In conclusion, HF is not uncommon even after successful primary angioplasty for anterior AMI (nearly one patient out of 5), is associated with hyperglycaemia and inflammation, a poor microvascular reperfusion, and left ventricular systolic function, and is more frequently complicated by adverse LV remodelling and lack of LV recovery. Copyright © 2013. Published by Elsevier SAS.

Application of the newly developed Japanese adenosine normal database for adenosine stress myocardial scintigraphy.

PubMed

Harata, Shingo; Isobe, Satoshi; Morishima, Itsuro; Suzuki, Susumu; Tsuboi, Hideyuki; Sone, Takahito; Ishii, Hideki; Murohara, Toyoaki

2015-10-01

The currently available Japanese normal database (NDB) in stress myocardial perfusion scintigraphy recommended by the Japanese Society of Nuclear Medicine (JSNM-NDB) is created based on the data from exercise tests. The newly developed adenosine normal database (ADS-NDB) remains to be validated for patients undergoing adenosine stress test. We tested whether the diagnostic accuracy of adenosine stress test is improved by the use of ADS-NDB (Kanazawa University). Of 233 consecutive patients undergoing (99m)Tc-MIBI adenosine stress test, 112 patients were tested. The stress/rest myocardial (99m)Tc-MIBI single-photon emission computed tomography (SPECT) images were analyzed by AutoQUANT 7.2 with both ADS-NDB and JSNM-NDB. The summed stress score (SSS) and summed difference score (SDS) were calculated. The agreements of the post-stress defect severity between ADS-NDB and JSNM-NDB were assessed using a weighted kappa statistic. In all patients, mean SSSs of all, right coronary artery (RCA), left anterior descending (LAD), and left circumflex (LCx) territories were significantly lower with ADS-NDB than those with JSNM-NDB. Mean SDSs in all, RCA, and LAD territories were significantly lower with ADS-NDB than those with JSNM-NDB. In 28 patients with significant coronary stenosis, the mean SSS in the RCA territory was significantly lower with ADS-NDB than that with JSNM-NDB. In 84 patients without ischemia, both mean SSSs and SDSs in all, RCA, LAD, and LCx territories were significantly lower with ADS-NDB than those with JSNM-NDB. Weighted kappa values of all patients, patients with significant stenosis, and patients without ischemia were 0.89, 0.83, and 0.92, respectively. Differences were observed between results from ADS-NDB and JSNM-NDB. The diagnostic accuracy of adenosine stress myocardial perfusion scintigraphy may be improved by reducing false-positive results.

Deep inspiration breath hold with electromagnetic confirmation of chest wall position for adjuvant therapy of left-sided breast cancer: Technique and accuracy.

PubMed

Kathpal, Madeera; Tinnel, Brent; Sun, Kelly; Ninneman, Stephanie; Malmer, Cynthia; Wendt, Stacie; Buff, Sheena; Valentich, David; Gossweiler, Marisa; Macdonald, Dusten

2016-01-01

With most patients now living long after their breast cancer diagnosis, minimizing long-term side effects of breast cancer treatment, such as reducing late cardiac and pulmonary side effects of radiation therapy (RT), is particularly important. It is now possible to use an electromagnetic tracking system to allow real-time tracking of chest wall (CW) position during the delivery of RT. Here, we report our experience using electromagnetic surface transponders as an added measure of CW position during deep inspiration breath hold (DIBH). We conducted a single-institution institutional review board-approved retrospective review of 15 female left-sided breast cancer patients treated between July 2012 and June 2013 with conventional whole breast radiation. We compared daily port films with treatment planning digitally reconstructed radiographs to establish daily setup accuracy, then used Calypso tracings to compare the position of the CW during the daily port film with the position of the CW during that day's treatment to determine the reproducibility of the breath hold position. Finally, we created competing treatment plans not using DIBH and used a paired t test to compare mean heart (MH) and left anterior descending (LAD) coronary artery dose between the 2 techniques. Mean total error (inter- and intrafraction) was dominated by interfraction error and was greatest in the longitudinal direction with a mean of 2.13 mm and 2 standard deviations of 8.2 mm. DIBH significantly reduced MH and LAD dose versus free breathing plans (MH, 1.26 Gy vs 2.84 Gy, P ≤ .001; LAD, 5.49 Gy vs 18.15 Gy, P ≤ .001). This study demonstrates that DIBH with electromagnetic confirmation of CW position is feasible, and allows potential improvement in the accurate delivery of adjuvant RT therapy for breast cancer. Published by Elsevier Inc.

Composite versus conventional coronary artery bypass grafting strategy for the anterolateral territory: study protocol for a randomized controlled trial

PubMed Central

2013-01-01

Background In severe coronary artery disease, coronary artery bypass grafting (CABG) surgery is indicated to re-establish an adequate blood supply to the ischemic myocardium. Effectiveness of CABG surgery for symptom relief and mortality decrease should therefore depend on bypass graft patency. As bypass using a left internal mammary artery (LIMA)-to-left anterior descending coronary artery (LAD) anastomosis allows the best results in terms of graft patency, we designed a new surgical technique using a saphenous vein graft as a venous bridge to distribute the LIMA flow to the cardiac anterolateral territory. This novel strategy could extend the patency benefits associated to the LIMA. Other potential benefits of this technique include easier surgical technique, possibility to use saphenous vein grafts as vein patch angioplasty, shorter saphenous vein grafts requirement and reduced or eliminated manipulations of the ascendant aorta (and associated stroke risk). Methods/Design Between July 2012 and 2016, 200 patients undergoing a primary isolated CABG surgery using cardiopulmonary bypass with a LAD bypass graft and at least another target on the anterolateral territory will be randomized (1:1) according to 1) the new composite strategy and 2) the conventional strategy with a LIMA-to-LAD anastomosis and revascularization of the other anterolateral target(s) with a separated aorto-coronary saphenous vein graft. The primary objective of the trial is to assess whether the composite strategy allows non-inferior anterolateral graft patency index (proportion of non-occluded CABGs out of the total number of CABGs) compared to the conventional technique. The primary outcome is the anterolateral graft patency index, evaluated at one year by 256-slice computed tomography angiography. Ten years of clinical follow-up is planned to assess clinical outcomes including death, myocardial infarction and need for revascularization. Discussion This non-inferiority trial has the potential to advance the adult cardiac surgery field, given the potential benefits associated with the composite grafting strategy. Trial registration ClinicalTrials.gov: NCT01585285. PMID:23971858

Influence of myocardial oxygen demand on the coronary vascular response to arterial blood gas changes in humans.

PubMed

Vermeulen, Tyler Dennis; Boulet, Lindsey M; Stembridge, Mike; Williams, Alexandra Mackenzie; Anholm, James D; Subedi, Prajan; Gasho, Chris; Ainslie, Philip N; Feigl, Eric O; Foster, Glen Edward

2018-03-30

It remains unclear if the human coronary vasculature is inherently sensitive to changes in arterial PO 2 and PCO 2 or if coronary vascular responses are the result of concomitant increases in myocardial O 2 consumption/demand (MVO 2 ). We hypothesized that the coronary vascular response to PO 2 and PCO 2 would be attenuated in healthy men when MVO 2 was attenuated with β 1 -adrenergic receptor blockade. Healthy men (n=11; age: 25 {plus minus} 1 years) received intravenous esmolol (β 1 -adrenergic receptor antagonist) or volume-matched saline in a double-blind, randomized, crossover study, and were exposed to poikilocapnic hypoxia, isocapnic hypoxia, and hypercapnic hypoxia. Measurements made at baseline and following 5-min of steady state at each gas manipulation included left anterior descending coronary blood velocity (LAD V ; Doppler echocardiography), heart rate and arterial blood pressure. LAD V values at the end of each hypoxic condition were compared between esmolol and placebo. Rate pressure product (RPP) and left-ventricular mechanical energy (ME LV ) were calculated as indices of MVO 2 . All gas manipulations augmented RPP, ME LV , and LAD V but only RPP and ME LV were attenuated (4-18%) following β 1 -adrenergic receptor blockade (P<0.05). Despite attenuated RPP and MELV responses, β 1 -adrenergic receptor blockade did not attenuate the mean LADV vasodilatory response when compared to placebo during poikilocapnic hypoxia (29.4{plus minus}2.2 vs. 27.3{plus minus}1.6 cm/s) and isocapnic hypoxia (29.5{plus minus}1.5 vs. 30.3{plus minus}2.2 cm/s). Hypercapnic hypoxia elicited a feed-forward coronary dilation that was blocked by β 1 -adrenergic receptor blockade. These results indicate a direct influence of arterial PO 2 on coronary vascular regulation that is independent of MVO 2 .

Impact of a New Adaptive Statistical Iterative Reconstruction (ASIR)-V Algorithm on Image Quality in Coronary Computed Tomography Angiography.

PubMed

Pontone, Gianluca; Muscogiuri, Giuseppe; Andreini, Daniele; Guaricci, Andrea I; Guglielmo, Marco; Baggiano, Andrea; Fazzari, Fabio; Mushtaq, Saima; Conte, Edoardo; Annoni, Andrea; Formenti, Alberto; Mancini, Elisabetta; Verdecchia, Massimo; Campari, Alessandro; Martini, Chiara; Gatti, Marco; Fusini, Laura; Bonfanti, Lorenzo; Consiglio, Elisa; Rabbat, Mark G; Bartorelli, Antonio L; Pepi, Mauro

2018-03-27

A new postprocessing algorithm named adaptive statistical iterative reconstruction (ASIR)-V has been recently introduced. The aim of this article was to analyze the impact of ASIR-V algorithm on signal, noise, and image quality of coronary computed tomography angiography. Fifty consecutive patients underwent clinically indicated coronary computed tomography angiography (Revolution CT; GE Healthcare, Milwaukee, WI). Images were reconstructed using filtered back projection and ASIR-V 0%, and a combination of filtered back projection and ASIR-V 20%-80% and ASIR-V 100%. Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated for left main coronary artery (LM), left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA) and were compared between the different postprocessing algorithms used. Similarly a four-point Likert image quality score of coronary segments was graded for each dataset and compared. A cutoff value of P < .05 was considered statistically significant. Compared to ASIR-V 0%, ASIR-V 100% demonstrated a significant reduction of image noise in all coronaries (P < .01). Compared to ASIR-V 0%, SNR was significantly higher with ASIR-V 60% in LM (P < .01), LAD (P < .05), LCX (P < .05), and RCA (P < .01). Compared to ASIR-V 0%, CNR for ASIR-V ≥60% was significantly improved in LM (P < .01), LAD (P < .05), and RCA (P < .01), whereas LCX demonstrated a significant improvement with ASIR-V ≥80%. ASIR-V 60% had significantly better Likert image quality scores compared to ASIR-V 0% in segment-, vessel-, and patient-based analyses (P < .01). Reconstruction with ASIR-V 60% provides the optimal balance between image noise, SNR, CNR, and image quality. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

N-terminal pro-brain natriuretic peptide is related with coronary flow velocity reserve and diastolic dysfunction in patients with asymmetric hypertrophic cardiomyopathy.

PubMed

Tesic, Milorad; Seferovic, Jelena; Trifunovic, Danijela; Djordjevic-Dikic, Ana; Giga, Vojislav; Jovanovic, Ivana; Petrovic, Olga; Marinkovic, Jelena; Stankovic, Sanja; Stepanovic, Jelena; Ristic, Arsen; Petrovic, Milan; Mujovic, Nebojsa; Vujisic-Tesic, Bosiljka; Beleslin, Branko; Vukcevic, Vladan; Stankovic, Goran; Seferovic, Petar

2017-10-01

The relations of elevated N-terminal pro-brain natriuretic peptide (NT-pro-BNP) and cardiac ischemia in hypertrophic cardiomyopathy (HCM) patients is uncertain. Therefore we designed the study with the following aims: (1) to analyze plasma concentrations of NT-pro-BNP in various subsets of HCM patients; (2) to reveal the correlations of NT-pro-BNP, myocardial ischemia, and diastolic dysfunction; (3) to assess predictors of the elevated plasma levels of NT-pro-BNP. In 61 patients (mean age 48.9±16.3 years; 26 male) with asymmetric HCM plasma levels of NT-pro-BNP were obtained. Standard transthoracic examination, tissue Doppler echocardiography with measurement of transthoracic coronary flow velocity reserve (CFVR) in left anterior descending artery (LAD) was done. Mean natural logarithm value of NT-pro-BNP was 7.11±0.95pg/ml [median value 1133 (interquartile range 561-2442)pg/ml]. NT-pro-BNP was significantly higher in patients with higher NYHA class, in obstructive HCM, more severe mitral regurgitation, increased left atrial volume index (LAVI), presence of calcified mitral annulus, elevated left ventricular (LV) filling pressure and in decreased CFVR. Levels of NT-pro-BNP significantly correlated with the ratio of E/e' (r=0.534, p<0.001), LV outflow tract gradient (r=0.503, p=0.024), LAVI (r=0.443, p<0.001), while inversely correlated with CFVR LAD (r=-0.569, p<0.001). When multivariate analysis was done only CFVR LAD and E/e' emerged as independent predictors of NT-pro-BNP. Plasma levels of NT-pro-BNP were significantly higher in HCM patients with more advanced disease. Elevated NT-pro-BNP not only reflects the diastolic impairment of the LV, but it might also be the result of cardiac ischemia in patients with HCM. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Topologically-associating domains are stable units of replication-timing regulation

PubMed Central

Pope, Benjamin D.; Ryba, Tyrone; Dileep, Vishnu; Yue, Feng; Wu, Weisheng; Denas, Olgert; Vera, Daniel L.; Wang, Yanli; Hansen, R. Scott; Canfield, Theresa K.; Thurman, Robert E.; Cheng, Yong; Gülsoy, Günhan; Dennis, Jonathan H.; Snyder, Michael P.; Stamatoyannopoulos, John A.; Taylor, James; Hardison, Ross C.; Kahveci, Tamer; Ren, Bing; Gilbert, David M.

2014-01-01

Summary Eukaryotic chromosomes replicate in a temporal order known as the replication-timing program1. During mammalian development, at least half the genome changes replication timing, primarily in units of 400–800 kb (“replication domains”; RDs), whose positions are preserved in different cell types, conserved between species, and appear to confine long-range effects of chromosome rearrangements2–7. Early and late replication correlate strongly with open and closed chromatin compartments identified by high-resolution chromosome conformation capture (Hi-C), and, to a lesser extent, lamina-associated domains (LADs)4,5,8,9. Recent Hi-C mapping has unveiled a substructure of topologically-associating domains (TADs) that are largely conserved in their positions between cell types and are similar in size to RDs8,10. However, TADs can be further sub-stratified into smaller domains, challenging the significance of structures at any particular scale11,12. Moreover, attempts to reconcile TADs and LADs to replication-timing data have not revealed a common, underlying domain structure8,9,13. Here, we localize boundaries of RDs to the early-replicating border of replication-timing transitions and map their positions in 18 human and 13 mouse cell types. We demonstrate that, collectively, RD boundaries share a near one-to-one correlation with TAD boundaries, whereas within a cell type, adjacent TADs that replicate at similar times obscure RD boundaries, largely accounting for the previously reported lack of alignment. Moreover, cell-type specific replication timing of TADs partitions the genome into two large-scale sub-nuclear compartments revealing that replication-timing transitions are indistinguishable from late-replicating regions in chromatin composition and lamina association and accounting for the reduced correlation of replication timing to LADs and heterochromatin. Our results reconcile cell type specific sub-nuclear compartmentalization with developmentally stable chromosome domains and offer a unified model for large-scale chromosome structure and function. PMID:25409831

DEKOIS: demanding evaluation kits for objective in silico screening--a versatile tool for benchmarking docking programs and scoring functions.

PubMed

Vogel, Simon M; Bauer, Matthias R; Boeckler, Frank M

2011-10-24

For widely applied in silico screening techniques success depends on the rational selection of an appropriate method. We herein present a fast, versatile, and robust method to construct demanding evaluation kits for objective in silico screening (DEKOIS). This automated process enables creating tailor-made decoy sets for any given sets of bioactives. It facilitates a target-dependent validation of docking algorithms and scoring functions helping to save time and resources. We have developed metrics for assessing and improving decoy set quality and employ them to investigate how decoy embedding affects docking. We demonstrate that screening performance is target-dependent and can be impaired by latent actives in the decoy set (LADS) or enhanced by poor decoy embedding. The presented method allows extending and complementing the collection of publicly available high quality decoy sets toward new target space. All present and future DEKOIS data sets will be made accessible at www.dekois.com.

Cancer as a dysregulated epigenome allowing cellular growth advantage at the expense of the host

PubMed Central

Timp, Winston; Feinberg, Andrew P.

2015-01-01

Although at the genetic level cancer is caused by diverse mutations, epigenetic modifications are characteristic of all cancers, from apparently normal precursor tissue to advanced metastatic disease, and these epigenetic modifications drive tumour cell heterogeneity. We propose a unifying model of cancer in which epigenetic dysregulation allows rapid selection for tumour cell survival at the expense of the host. Mechanisms involve both genetic mutations and epigenetic modifications that disrupt the function of genes that regulate the epigenome itself. Several exciting recent discoveries also point to a genome-scale disruption of the epigenome that involves large blocks of DNA hypomethylation, mutations of epigenetic modifier genes and alterations of heterochromatin in cancer (including large organized chromatin lysine modifications (LOCKs) and lamin-associated domains (LADs)), all of which increase epigenetic and gene expression plasticity. Our model suggests a new approach to cancer diagnosis and therapy that focuses on epigenetic dysregulation and has great potential for risk detection and chemoprevention. PMID:23760024

Oxygen supply (HbO2) in beating hearts of 14 coronary patients obtained by tissue monitoring with optical sensors

NASA Astrophysics Data System (ADS)

Frank, Klaus H.; Kloevekorn, P.; Zuendorf, J.; Kessler, Manfred D.

2002-06-01

Local intra capillary HbO2 was monitored in beating hearts of 14 patients undergoing coronary bypass surgery. The spectra were measured in the epicardium of the left ventricle, supplied by the left coronary artery (LAD). All selected patients suffered form stenosis or occlusion of two to three vessels. The patients suffered from severe angina and showed hypokinesia in the angiography. Micro-light guide fibers with a diameter of 75micrometers were used for monitoring before and after bypass surgery. These light guides were connected to the Erlanger Micro Light guide Spectro Photometer EMPHO for registration. Local measurements were performed in the epicardium of the left ventricle in 25 areas 2.25cm2 each. Integrated gradient fields were plotted for each of the 14 patients before and after bypass surgery. The mean values of HbO2 in the respective areas were calculated and evaluated against the local value distribution.

"'Lad" Research, the Reproduction of Stereotypes? Ethnographic Dilemmas When Researching Boys from Working-Class Backgrounds

ERIC Educational Resources Information Center

Rosvall, Per-Åke

2015-01-01

Previous research presented in this journal and elsewhere has suggested that vocational education is highly gender segregated and it is the heavy industrial sectors such as industry, vehicle and construction programmes that mainly attract boys with an anti-school attitude who are not interested in academic school work. However, there are good…

Side-branch wire entrapment during bifurcation PCI: avoidance and management.

PubMed

Burns, Andrew T; Gutman, Jack; Whitbourn, Rob

2010-02-15

An LAD/D1 bifurcation intervention was complicated by side-branch wire entrapment and unravelling requiring goose-neck snare removal. Residual microfilaments were retrieved from the main branch after further balloon inflations with a satisfactory final angiographic result and one-year follow-up. Various methods are available to avoid and deal with this complication.

U.S. EPA, Pesticide Product Label, MR. HOLIDAY CALCIUM HYPOCHLORITE, 09/03/1985

EPA Pesticide Factsheets

2011-04-19

... QrdICfR- IIfT'r (')'rt.~>W!: ~i!"W- \\l'" It(I t,e 1lII\\IICI \\II., De hUI t1 s.~ ,), r, oec 11\\ flitS ~ ~tI ct ~ !"'- iIIl'31:J~ ~!Jet \\.'Id\\I lAd rI/JI:I. ~ ~~~ Ut .... " M:!.t ...

Optical Characterization of Lead Monoxide Films Grown by Laser-Assisted Deposition

NASA Astrophysics Data System (ADS)

Baleva, M.; Tuncheva, V.

1994-05-01

The Raman spectra of PbO films, grown by laser-assisted deposition (LAD) at different substrate temperatures are investigated. The spectra of the films, deposited on amorphous, single crystal quartz and polycrystal PbTe substrates, are compared with the Raman spectra of tetragonal and orthorhombic powder samples. The phonon frequencies determined in our experiment with powder samples coincide fairly well with those obtained by Adams and Stevens, J. Chem. Soc., Dalton Trans., 1096 (1977). Thus the Raman spectra of the powder samples presented in this paper can be considered as unambiguous characteristics of the two different PbO crystal phases. It was concluded that the Raman scattering may serve as a tool for identification of PbO films and their crystal modifications. On the basis of this investigation it was concluded that the film structure changes from orthorhombic to tetragonal with increased substrate temperature, and that the nature of the substrate influences the crystal structure of the films. On the basis of the Raman spectra of the β-PbO films with prevailing (001) orientation of crystallization, an assignment of the modes is proposed.

Simulator Fidelity: A Concept Paper

DTIC Science & Technology

1980-11-01

training programs, it should be possible to screen out those trainees who do not possess the required abilities to benefit from a given training program...PTZ!L-CAC-IM I USACAC ýITN:Z ArIL-CA(.-IA I IJSAC&%CUA ArrIN’ AT?D.--CAC-A 1 UiSA i.LICTHONIC WAqFAHk LAd CHILI INTLLLIGENCE MAYER nEVEL SUPP OFF I

Delta 181 Sensor Module Command Center.

DTIC Science & Technology

1989-09-01

CIIkC ilsh ~~’,r~l~ ladJhc dl loli l-l e k I w M1,M 71o’ fl.k IhcJ ci~ll I 1001 tI’lIdI -C & ’ 1 ok~lto li ",1,(IM 11,1i’ ’’ ’ ,PPt 1 E ) PH’Y H.1 s i

Study of the Polarization Properties of the Crab Nebula and Pulsar with BATSE

NASA Technical Reports Server (NTRS)

Forrest, David J.; Vestrand, W. T.; McConnell, Mark

1997-01-01

Activities carried out under this proposal included: 1) development and refinements of Monte Carlo simulations of the atmospheric reflected albedo hard x-ray emissions, both unpolarized and polarized, 2) modeling and simulations of the off-axis response of the BATSE LAD detectors, and 3) comparison of our simulation results with numerous BATSE flare and cosmic burst data sets.

Maternal bradycardia occurring prior to onset of HELLP syndrome in a woman with pre-eclampsia.

PubMed

Hosokawa, Ami; Umazume, Takeshi; Yamada, Takahiro; Minakami, Hisanori

2017-05-13

A 36-year-old nulliparous woman developed pre-eclampsia at gestational week (GW) 28 -6/7 Cardiac status was checked regularly. Heart rate of 93 beats per minute (bpm) with left atrial diameter (LAD) of 35 mm, left ventricular hypertrophy and inferior vena cava diameter (IVCD) of 8 mm at GW 32 -0/7 decreased to 48 bpm with an expanded IVCD to 25 mm, dilated left atrium (LAD to 39 mm), increased pulmonary arterial pressure, increased systemic vascular resistance (approximate 3000  dyn s/cm 5 ) and biphasic intrarenal venous flow pattern 3.5 hours prior to childbirth at GW 32 -3/7 Epigastralgia, tachycardia (160 bpm) and marked hypertension (201/111 mm Hg) occurring 2 hours after echocardiography necessitated caesarean section, with subsequent development of HELLP syndrome. Acute fluid shift from the splanchnic vasculature to central vasculature may have occurred causing HELLP syndrome as a result from vasospasm associated with sympathetic hyperactivity. The cause of bradycardia prior to tachycardia remains unclear. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Computational Fluid Dynamics Analysis of the Effect of Plaques in the Left Coronary Artery

PubMed Central

Chaichana, Thanapong; Sun, Zhonghua; Jewkes, James

2012-01-01

This study was to investigate the hemodynamic effect of simulated plaques in left coronary artery models, which were generated from a sample patient's data. Plaques were simulated and placed at the left main stem and the left anterior descending (LAD) to produce at least 60% coronary stenosis. Computational fluid dynamics analysis was performed to simulate realistic physiological conditions that reflect the in vivo cardiac hemodynamics, and comparison of wall shear stress (WSS) between Newtonian and non-Newtonian fluid models was performed. The pressure gradient (PSG) and flow velocities in the left coronary artery were measured and compared in the left coronary models with and without presence of plaques during cardiac cycle. Our results showed that the highest PSG was observed in stenotic regions caused by the plaques. Low flow velocity areas were found at postplaque locations in the left circumflex, LAD, and bifurcation. WSS at the stenotic locations was similar between the non-Newtonian and Newtonian models although some more details were observed with non-Newtonian model. There is a direct correlation between coronary plaques and subsequent hemodynamic changes, based on the simulation of plaques in the realistic coronary models. PMID:22400051

Conditional control of selectin ligand expression and global fucosylation events in mice with a targeted mutation at the FX locus.

PubMed

Smith, Peter L; Myers, Jay T; Rogers, Clare E; Zhou, Lan; Petryniak, Bronia; Becker, Daniel J; Homeister, Jonathon W; Lowe, John B

2002-08-19

Glycoprotein fucosylation enables fringe-dependent modulation of signal transduction by Notch transmembrane receptors, contributes to selectin-dependent leukocyte trafficking, and is faulty in leukocyte adhesion deficiency (LAD) type II, also known as congenital disorder of glycosylation (CDG)-IIc, a rare human disorder characterized by psychomotor defects, developmental abnormalities, and leukocyte adhesion defects. We report here that mice with an induced null mutation in the FX locus, which encodes an enzyme in the de novo pathway for GDP-fucose synthesis, exhibit a virtually complete deficiency of cellular fucosylation, and variable frequency of intrauterine demise determined by parental FX genotype. Live-born FX(-/-) mice exhibit postnatal failure to thrive that is suppressed with a fucose-supplemented diet. FX(-/-) adults suffer from an extreme neutrophilia, myeloproliferation, and absence of leukocyte selectin ligand expression reminiscent of LAD-II/CDG-IIc. Contingent restoration of leukocyte and endothelial selectin ligand expression, general cellular fucosylation, and normal postnatal physiology is achieved by modulating dietary fucose to supply a salvage pathway for GDP-fucose synthesis. Conditional control of fucosylation in FX(-/-) mice identifies cellular fucosylation events as essential concomitants to fertility, early growth and development, and leukocyte adhesion.

Argonaute2 and LaminB modulate gene expression by controlling chromatin topology

PubMed Central

Nazer, Ezequiel; Dale, Ryan K.; Chinen, Madoka; Radmanesh, Behram

2018-01-01

Drosophila Argonaute2 (AGO2) has been shown to regulate expression of certain loci in an RNA interference (RNAi)-independent manner, but its genome-wide function on chromatin remains unknown. Here, we identified the nuclear scaffolding protein LaminB as a novel interactor of AGO2. When either AGO2 or LaminB are depleted in Kc cells, similar transcription changes are observed genome-wide. In particular, changes in expression occur mainly in active or potentially active chromatin, both inside and outside LaminB-associated domains (LADs). Furthermore, we identified a somatic target of AGO2 transcriptional repression, no hitter (nht), which is immersed in a LAD located within a repressive topologically-associated domain (TAD). Null mutation but not catalytic inactivation of AGO2 leads to ectopic expression of nht and downstream spermatogenesis genes. Depletion of either AGO2 or LaminB results in reduced looping interactions within the nht TAD as well as ectopic inter-TAD interactions, as detected by 4C-seq analysis. Overall, our findings reveal coordination of AGO2 and LaminB function to dictate genome architecture and thereby regulate gene expression. PMID:29529026

Alternating high and low climate variability: The context of natural selection and speciation in Plio-Pleistocene hominin evolution.

PubMed

Potts, Richard; Faith, J Tyler

2015-10-01

Interaction of orbital insolation cycles defines a predictive model of alternating phases of high- and low-climate variability for tropical East Africa over the past 5 million years. This model, which is described in terms of climate variability stages, implies repeated increases in landscape/resource instability and intervening periods of stability in East Africa. It predicts eight prolonged (>192 kyr) eras of intensified habitat instability (high variability stages) in which hominin evolutionary innovations are likely to have occurred, potentially by variability selection. The prediction that repeated shifts toward high climate variability affected paleoenvironments and evolution is tested in three ways. In the first test, deep-sea records of northeast African terrigenous dust flux (Sites 721/722) and eastern Mediterranean sapropels (Site 967A) show increased and decreased variability in concert with predicted shifts in climate variability. These regional measurements of climate dynamics are complemented by stratigraphic observations in five basins with lengthy stratigraphic and paleoenvironmental records: the mid-Pleistocene Olorgesailie Basin, the Plio-Pleistocene Turkana and Olduvai Basins, and the Pliocene Tugen Hills sequence and Hadar Basin--all of which show that highly variable landscapes inhabited by hominin populations were indeed concentrated in predicted stages of prolonged high climate variability. Second, stringent null-model tests demonstrate a significant association of currently known first and last appearance datums (FADs and LADs) of the major hominin lineages, suites of technological behaviors, and dispersal events with the predicted intervals of prolonged high climate variability. Palynological study in the Nihewan Basin, China, provides a third test, which shows the occupation of highly diverse habitats in eastern Asia, consistent with the predicted increase in adaptability in dispersing Oldowan hominins. Integration of fossil, archeological, sedimentary, and paleolandscape evidence illustrates the potential influence of prolonged high variability on the origin and spread of critical adaptations and lineages in the evolution of Homo. The growing body of data concerning environmental dynamics supports the idea that the evolution of adaptability in response to climate and overall ecological instability represents a unifying theme in hominin evolutionary history. Published by Elsevier Ltd.

A new 4-variable formula to differentiate normal variant ST segment elevation in V2-V4 (early repolarization) from subtle left anterior descending coronary occlusion - Adding QRS amplitude of V2 improves the model.

PubMed

Driver, Brian E; Khalil, Ayesha; Henry, Timothy; Kazmi, Faraz; Adil, Amina; Smith, Stephen W

Precordial normal variant ST elevation (NV-STE), previously often called "early repolarization," may be difficult to differentiate from subtle ischemic STE due to left anterior descending (LAD) occlusion. We previously derived and validated a logistic regression formula that was far superior to STE alone for differentiating the two entities on the ECG. The tool uses R-wave amplitude in lead V4 (RAV4), ST elevation at 60 ms after the J-point in lead V3 (STE60V3) and the computerized Bazett-corrected QT interval (QTc-B). The 3-variable formula is: 1.196 x STE60V3 + 0.059 × QTc-B - 0.326 × RAV4 with a value ≥23.4 likely to be acute myocardial infarction (AMI). Adding QRS voltage in V2 (QRSV2) would improve the accuracy of the formula. 355 consecutive cases of proven LAD occlusion were reviewed, and those that were obvious ST elevation myocardial infarction were excluded. Exclusion was based on one straight or convex ST segment in V2-V6, 1 millimeter of summed inferior ST depression, any anterior ST depression, Q-waves, "terminal QRS distortion," or any ST elevation >5 mm. The NV-STE group comprised emergency department patients with chest pain who ruled out for AMI by serial troponins, had a cardiologist ECG read of "NV-STE," and had at least 1 mm of STE in V2 and V3. R-wave amplitude in lead V4 (RAV4), ST elevation at 60 ms after the J-point in lead V3 (STE60V3) and the computerized Bazett-corrected QT interval (QTc-B) had previously been measured in all ECGs; physicians blinded to outcome then measured QRSV2 in all ECGs. A 4-variable formula was derived to more accurately classify LAD occlusion vs. NV-STE and optimize area under the curve (AUC) and compared with the previous 3-variable formula. There were 143 subtle LAD occlusions and 171 NV-STE. A low QRSV2 added diagnostic utility. The derived 4-variable formula is: 0.052*QTc-B - 0.151*QRSV2 - 0.268*RV4 + 1.062*STE60V3. The 3-variable formula had an AUC of 0.9538 vs. 0.9686 for the 4-variable formula (p = 0.0092). At the same specificity as the 3-variable formula [90.6%, at which cutpoint (≥23.4), 123 of 143 MI were correctly classified for 86% sensitivity], the sensitivity of the new formula at cutpoint ≥17.75 is 90.2%, with 129/143 correctly classified MI, identifying an additional 6 cases. The cutpoint with the highest accuracy (92.0%) was at a cutoff value ≥18.2, with 88.8% sensitivity, 94.7% specificity, and a positive and negative likelihood ratio of 16.9 (95% CI: 8.9-32) and 0.12 (95% CI: 0.07-0.19). At this cutpoint, it correctly classified an additional 11 cases (289 of 315, vs. 278 of 315): 127/143 for MI (an additional 4 cases) and 162/171 for NV-STE (an additional 7 cases). On the ECG, a 4-variable formula was derived which adds QRSV2; it differentiates subtle LAD occlusion from NV-STE better than the 3-variable formula. At a value ≥18.2, the formula (0.052*QTc-B - 0.151*QRSV2 - 0.268*RV4 + 1.062*STE60V3) was very accurate, sensitive, and specific, with excellent positive and negative likelihood ratios. This formula needs to be validated. Copyright © 2017 Elsevier Inc. All rights reserved.

Solar Thermal Upper Stage Liquid Hydrogen Pressure Control Testing

NASA Technical Reports Server (NTRS)

Moore, J. D.; Otto, J. M.; Cody, J. C.; Hastings, L. J.; Bryant, C. B.; Gautney, T. T.

2015-01-01

High-energy cryogenic propellant is an essential element in future space exploration programs. Therefore, NASA and its industrial partners are committed to an advanced development/technology program that will broaden the experience base for the entire cryogenic fluid management community. Furthermore, the high cost of microgravity experiments has motivated NASA to establish government/aerospace industry teams to aggressively explore combinations of ground testing and analytical modeling to the greatest extent possible, thereby benefitting both industry and government entities. One such team consisting of ManTech SRS, Inc., Edwards Air Force Base, and Marshall Space Flight Center (MSFC) was formed to pursue a technology project designed to demonstrate technology readiness for an SRS liquid hydrogen (LH2) in-space propellant management concept. The subject testing was cooperatively performed June 21-30, 2000, through a partially reimbursable Space Act Agreement between SRS, MSFC, and the Air Force Research Laboratory. The joint statement of work used to guide the technical activity is presented in appendix A. The key elements of the SRS concept consisted of an LH2 storage and supply system that used all of the vented H2 for solar engine thrusting, accommodated pressure control without a thermodynamic vent system (TVS), and minimized or eliminated the need for a capillary liquid acquisition device (LAD). The strategy was to balance the LH2 storage tank pressure control requirements with the engine thrusting requirements to selectively provide either liquid or vapor H2 at a controlled rate to a solar thermal engine in the low-gravity environment of space operations. The overall test objective was to verify that the proposed concept could enable simultaneous control of LH2 tank pressure and feed system flow to the thruster without necessitating a TVS and a capillary LAD. The primary program objectives were designed to demonstrate technology readiness of the SRS concept at a system level as a first step toward actual flight vehicle demonstrations. More specific objectives included testing the pressure and feed control system concept hardware for functionality, operability, and performance. Valuable LH2 thermodynamic and fluid dynamics data were obtained for application to both the SRS concept and to future missions requiring space-based cryogen propellant management.

TU-EF-304-12: Proton Radiation Therapy for Left-Sided Breast Cancer: LET and RBE Considerations for Cardiac Toxicity

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

Giantsoudi, D; Jee, K; MacDonald, S

Purpose: Increased risk of coronary artery disease has been documented for patients treated with radiation for left-sided breast cancer. Proton therapy (PRT) has been shown to significantly decrease cardiac irradiation, however variations in relative biological effectiveness (RBE) have been ignored so far. In this study we evaluate the impact of accounting for RBE variations on sensitive structures located within high linear energy transfer (LET) areas (distal end) of the proton treatment fields, for this treatment site. Methods: Three patients treated in our institution with PRT for left-sided breast cancer were selected. All patients underwent reconstructive surgery after mastectomy and treatedmore » to a total dose of 50.4Gy with beam(s) vertical to the chest wall. Dose and LET distributions were calculated using Monte Carlo (MC-TOPAS - TOol for PArticle Simulation). The LET-based, variable-RBE-weighted dose was compared to the analytical calculation algorithm (ACA) and MC dose distributions for a constant RBE of 1.1, based on volume histograms and mean values for the target, heart and left anterior descending coronary artery (LAD). Results: Assuming a constant RBE and compared to the ACA dose, MC predicted lower mean target and heart doses by 0.5% to 2.7% of the prescription dose. For variable RBE, plan evaluation showed increased mean target dose by up to 5%. Mean variable-RBE-weighted doses for the LAD ranged from 2.7 to 5.9Gy(RBE) among patients increased by 41%–64.2% compared to constant RBE ACA calculation (absolute dose: 1.7–3.9Gy(RBE)). Smaller increase in mean heart doses was noticed. Conclusion: ACA overestimates the target mean dose by up to 2.7%. However, disregarding variations in RBE may lead to significant underestimation of the dose to sensitive structures at the distal end of the proton treatment field and could thus impact outcome modeling for cardiac toxicities after proton therapy. These results are subject to RBE model and parameter uncertainties.« less

How synchronous are neogene marine plankton events?

NASA Astrophysics Data System (ADS)

Spencer-Cervato, Cinzia; Thierstein, Hans R.; Lazarus, David B.; Beckmann, Jean-Pierre

1994-10-01

An electronic supplement of this material may be obtained on adiskette or Anonymous FTP from KOSMOS.AGU.ORG. (LOGIN toAGU's FTP account using ANONYMOUS as the username andGUEST as the password. Go to the right directory by typing CDAPEND. Type LS to see what files are available. Type GET and thename of the file to get it. Finally, type EXIT to leave the system.)(Paper 94PA01456, How synchronous are Neogene marine planktonevents?, by C. Spencer-Cervato, H. R. Thierstein, D. B. Lazarus, andJ-P Beckmann). Diskette may be ordered from American GeophysicalUnion, 2000 Florida Avenue, N.W., Washington, DC 20009; $15.00.Payment must accompany order.We analyzed the synchrony and diachrony of commonly used Neogene biostratigraphic events from data published in the Initial Reports of the Deep Sea Drilling Project (DSDP) and in the Proceedings of the Ocean Drilling Program (ODP). On the basis of the combined biostratigraphic and magnetostratigraphic evidence, new Neogene age models were constructed for 35 globally distributed DSDP and ODP holes. Biostratigraphic events from the four major plankton groups (calcareous nannofossils, diatoms, planktonic foraminifera, and radiolarians) were compiled from DSDP and ODP reports. After the elimination of possible sources of error such as stratigraphic hiatuses and reworking of specimens, 124 biostratigraphic events that occurred in at least four holes were analyzed in detail: for each event a biochronologic age estimate was derived by projection of the depth of the event onto the line of correlation of each hole, and from these a global mean age for each event was calculated, together with its standard deviation. Average standard deviations for event ages by fossil group are: calcareous nannofossil first appearance datums (FADs): 0.57 m.y. (21 events), calcareous nannofossil last appearance datums (LADs): 0.60 m.y. (25 events), diatom FADs: 0.57 m.y. (7 events), diatom LADs: 0.85 m.y. (14 events), planktonic foraminifera FADs: 0.88 m.y. (22 events), foraminifera LADs: 0.68 m.y. (16 events), radiolarian FADs: 0.30 m.y. (9 events), radiolarian LADs: 0.31 m.y. (10 events). Since the average sample spacing in the sites used for this analysis is only 0.185 m.y., we have examined the data for true patterns of diachrony and for other biases. Diachrony is more frequent among cosmopolitan than among endemic taxa, thus there is a general trade-off between the obtainable age precision and the geographic extent of a bioevent. Precision of age calibrations also decreases with increasing age. Although some of these features may be due to investigator bias, they appear in part to be real phenomena, and thus could also provide opportunities for further exploration of important paleobiological processes, such as change in environmental gradients through time, evolutionary adaptation of species populations and migration due to water mass changes.

Geiger Counter Technique

DTIC Science & Technology

1942-01-01

ONLY; ADMINISTRATIVE/OPERATIONAL USE; 03 MAR 1999. OTHER REQUESTS SHALL BE REFERRED THROUGH COMMANDING OFFICER, NAVAL RESEARCH LAB , WASHINGTON, DC 20375...Used as Glow Tube Voltage + " -- -+a...... .-..... . .... . . . . . .. . . Plate 41. Tar of aCotrolust Voltaep with Gas Pressure lab A-gtarator of’ Plate...construation cf vapor comatera. Acst Lay metal wll menru as cathode aterial, but oxidiste copper Lad bras han given beest res-ts. fe ride choice of

Porcine (Sus scrofa) Chronic Myocardial Infarction Model Development

DTIC Science & Technology

2015-04-03

Change from 8 mini pigs to 6 farm pigs and 2 mini pigs 3 Personnel added: Southard, Riddock 4 Personnel added: Julian 2 FDGXXX 6. FUNDING...models. Methods: Eight Yucatan miniature pigs underwent percutaneous embolization of the D1-LAD via injection of 90 µm polystyrene micro-spheres...myocardial structure and extracellular matrix composition respectively. Results: Overall procedural survival rate was 83% (5/6) with one pig

Local Area Defense (LAD) Demonstration

DTIC Science & Technology

2004-09-01

Prozac ? Fentanyl? Institution, incident command, community drills - use of internet - digital photos of all victims to follow them through the system...and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503 1. AGENCY USE ONLY 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED (Leave...detection and rapid response system for local area defense using the University of Maryland Baltimore (UMB) Campus as a testbed. Additional goals includes

Simulating historical variability in the amount of old forests in the Oregon Coast Range.

Treesearch

M.C. Wimberly; T.M. Spies; C.J. Long; C. Whitlock

2000-01-01

We developed the landscape age-class demographics simulator (LADS) to model historical variability in the amount of old-growth and late-successional forest in the Oregon Coast Range over the past 3,000 years. The model simulated temporal and spatial patterns of forest fires along with the resulting fluctuations in the distribution of forest age classes across the...

SU-D-18A-06: Variation of Controlled Breath Hold From CT Simulation to Treatment and Its Dosimetric Impact for Left-Sided Breast Radiotherapy with a Real-Time Optical Tracking System

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

Mittauer, K; Deraniyagala, R; Li, J

2014-06-01

Purpose: Different breath-hold (BH) maneuvers (abdominal breathing vs. chest breathing) during CT simulation and treatment can lead to chest wall positional variation. The purpose of this study is to quantify the variation of active breathing control (ABC)-assisted BH and estimate its dosimetric impact for left-sided whole-breast radiotherapy with a real-time optical tracking system (OTS). Methods: Seven breast cancer patients were included. An in-house OTS tracked an infrared (IR) marker affixed over the xiphoid process of the patient at CT simulation and throughout the treatment course to measure BH variations. Correlation between the IR marker and the breast was studied formore » dosimetric purposes. The positional variations of 860 BHs were retrospectively incorporated into treatment plans to assess their dosimetric impact on breast and cardiac organs (heart and left anterior descending artery [LAD]). Results: The mean intrafraction variations were 2.8 mm, 2.7 mm, and 1.6 mm in the anteroposterior (AP), craniocaudal (CC), and mediolateral (ML) directions, respectively. Mean stability in any direction was within 1.5 mm. A general trend of BH undershoot at treatment relative to CT simulation was observed with an average of 4.4 mm, 3.6 mm, and 0.1 mm in the AP, CC, and ML directions, respectively. Undershoot up to 12.6 mm was observed for individual patients. The difference between the planned and delivered dose to breast targets was negligible. The average planned/delivered mean heart doses, mean LAD doses, and max LAD doses were 1.4/2.1, 7.4/15.7, and 18.6/31.0 Gy, respectively. Conclusion: Systematic undershoot was observed in ABC-assisted BHs from CT simulation to treatment. Its dosimetric impact on breast coverage was minimized with image guidance, but the benefits of cardiac organ sparing were degraded. A real-time tracking system can be used in junction with the ABC device to improve BH reproducibility.« less

SU-F-T-418: Evaluation of Organs at Risk (OAR) Sparing in Left Breast Irradiation Techniques

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

Saini, A; Hwang, C; Das, I

Purpose: To compare dose to organs at risk (OAR) for left sided breast radiation therapy with comparable planning target volume (PTV) coverage in three techniques; free breathing in supine position (FB), deep inspirational breath hold in supine (DIBH) and free breathing in prone position (PP). Methods: Ten left sided breast cancer patients suitable for this study underwent a CT scan in three techniques e.g. supine, FB and DIBH and prone position (PP). One radiation oncologist contoured the PTV and OAR (cardiac components) based on RTOG guidelines. Treatment plans were optimized using field-in-field technique with AAA algorithm. Each plan was optimizedmore » to provide identical coverage to PTV such that a reasonable comparison in OAR dosimetry can be evaluated. The prescribed dose to PTV were 42.56 Gy; 2.66 Gy in 16 fractions. Results: Average lung dose parameters; Dmean, V10, V20 and V30 were 0.5 Gy, 0.6%, 0.2%, and 0.1% respectively in PP which is significantly lower than FB (5.9 Gy, 14.2%, 10.7 %, and 8.4%) and DIBH (5.8 Gy, 14.3%, 10.2%, 7.8%). Similarly average heart Dmean, V2.5, V5, V10, and V20 were much lower in PP (1.2Gy, 9.1%, 2.1%, 0.8%, and 0.4%), and in DIBH (1.2 Gy, 10.6%, 1.7%, 0.5%, and 0.1%) compared to FB (2.6 Gy, 21%, 7.2%, 4.4% and 3.3%) respectively. Similar findings were also noted in the heart component left anterior descending artery (LAD) and Left ventricle (LV) which are correlated to radiation related toxicity. Conclusion: Based on the calculated dose, FB technique provides highest heart and lung dose. Prone has lowest lung dose, and DIBH has lowest LAD dose. It is found that PP is always superior for heart, LV, LAD and lung as compared to FB. This conclusion is in contrast to some published study concluding that prone position has no benefit for heart sparing.« less

Motion-corrected whole-heart PET-MR for the simultaneous visualisation of coronary artery integrity and myocardial viability: an initial clinical validation.

PubMed

Munoz, Camila; Kunze, Karl P; Neji, Radhouene; Vitadello, Teresa; Rischpler, Christoph; Botnar, René M; Nekolla, Stephan G; Prieto, Claudia

2018-05-12

Cardiac PET-MR has shown potential for the comprehensive assessment of coronary heart disease. However, image degradation due to physiological motion remains a challenge that could hinder the adoption of this technology in clinical practice. The purpose of this study was to validate a recently proposed respiratory motion-corrected PET-MR framework for the simultaneous visualisation of myocardial viability ( 18 F-FDG PET) and coronary artery anatomy (coronary MR angiography, CMRA) in patients with chronic total occlusion (CTO). A cohort of 14 patients was scanned with the proposed PET-CMRA framework. PET and CMRA images were reconstructed with and without the proposed motion correction approach for comparison purposes. Metrics of image quality including visible vessel length and sharpness were obtained for CMRA for both the right and left anterior descending coronary arteries (RCA, LAD), and relative increase in 18 F-FDG PET signal after motion correction for standard 17-segment polar maps was computed. Resulting coronary anatomy by CMRA and myocardial integrity by PET were visually compared against X-ray angiography and conventional Late Gadolinium Enhancement (LGE) MRI, respectively. Motion correction increased CMRA visible vessel length by 49.9% and 32.6% (RCA, LAD) and vessel sharpness by 12.3% and 18.9% (RCA, LAD) on average compared to uncorrected images. Coronary lumen delineation on motion-corrected CMRA images was in good agreement with X-ray angiography findings. For PET, motion correction resulted in an average 8% increase in 18 F-FDG signal in the inferior and inferolateral segments of the myocardial wall. An improved delineation of myocardial viability defects and reduced noise in the 18 F-FDG PET images was observed, improving correspondence to subendocardial LGE-MRI findings compared to uncorrected images. The feasibility of the PET-CMRA framework for simultaneous cardiac PET-MR imaging in a short and predictable scan time (~11 min) has been demonstrated in 14 patients with CTO. Motion correction increased visible length and sharpness of the coronary arteries by CMRA, and improved delineation of the myocardium by 18 F-FDG PET, resulting in good agreement with X-ray angiography and LGE-MRI.

Usefulness of MRI to Differentiate Between Temporary and Long-Term Coronary Artery Occlusion in a Minimally Invasive Model of Experimental Myocardial Infarction

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

Abegunewardene, Nico, E-mail: nico@uni-mainz.de; Vosseler, Markus; Gori, Tommaso

The surgical technique employed to determine an experimental ischemic damage is a major factor in the subsequent process of myocardial scar development. We set out to establish a minimally invasive porcine model of myocardial infarction using cardiac contrast-enhanced magnetic resonance imaging (ce-MRI) as the basic diagnostic tool. Twenty-seven domestic pigs were randomized to either temporary or permanent occlusion of the left anterior descending artery (LAD). Temporary occlusion was achieved by inflation of a percutaneous balloon in the left anterior descending artery directly beyond the second diagonal branch. Occlusion was maintained for 30 or 45 min, followed by reperfusion. Permanent occlusionmore » was achieved via thrombin injection. Thirteen animals died peri- or postinterventionally due to arrhythmias. Fourteen animals survived the 30-min ischemia (four animals; group 1), the 45-min ischemia (six animals; group 2), or the permanent occlusion (4 animals; group 3). Coronary angiography and ce-MRI were performed 8 weeks after coronary occlusion to document the coronary flow grade and the size of myocardial scar tissue. The LAD was patent in all animals in groups 1 and 2, with normal TIMI flow; in group 3 animals, the LAD was totally occluded. Fibrosis of the left ventricle in group 1 (4.9 {+-} 4.4%; p = 0.008) and group 2 (9.4 {+-} 2.9%; p = 0.05) was significantly lower than in group 3 (14.5 {+-} 3.9%). Wall thickness of the ischemic area was significantly lower in group 3 versus group 1 and group 2 (2.9 {+-} 0.3, 5.9 {+-} 0.7, and 6.1 {+-} 0.7 mm; p = 0.005). The extent of late enhancement of the left ventricle was also significantly higher in group 3 (16.9 {+-} 2.1%) compared to group 1 (5.3 {+-} 5.4%; p = 0.003) and group 2 (9.7 {+-} 3.4%, p = 0.013). In conclusion, the present model of minimally invasive infarction coupled with ce-MRI may represent a useful alternative to the open chest model for studies of myocardial infarction and scar development.« less

Comparative utility of gated myocardial perfusion imaging and transthoracic coronary flow reserve for the assessment of coronary artery disease in patients with left bundle branch block.

PubMed

Pavlovic, Smiljana; Sobic-Saranovic, Dragana; Djordjevic-Dikic, Ana; Beleslin, Branko; Stepanovic, Jelena; Artiko, Vera; Giga, Vojislav; Petrasinovic, Zorica; Ostojic, Miodrag; Vujisic-Tesic, Bosiljka; Obradovic, Vladimir

2010-04-01

To compare the diagnostic utility of gated single-photon emission computed tomography (SPECT) methoxy isobutyl isonitrile (MIBI) myocardial perfusion imaging and transthoracic Doppler echocardiography (TTDE) coronary flow reserve (CFR) to coronary angiography for detecting coronary artery disease (CAD) in patients with left bundle branch block (LBBB). Forty-three patients with complete LBBB and an intermediate pretest probability for CAD underwent dipyridamole stress TTDE and gated SPECT MIBI during the same session and coronary angiography within a month. The parameters of myocardial perfusion (summed stress score, summed difference scores) regional wall function (wall motion score, wall thickening score) and ejection fraction were derived using the 17-segment model and 4D-MSPECT software. TTDE variables included peak flow velocity at rest and during hyperemia in left anterior descending artery (LAD), based on which CFR was calculated (normal>2). Perfusion ischemic scores were significantly higher in group 1 with angiographic evidence of greater than 50% LAD stenosis compared with group 2 with less than 50% LAD stenosis (summed stress score 12.4+/-5.5 vs. 8.3+/-3.5, P<0.05, summed difference score 3.7+/-1.2 vs. 1.1+/-0.3, P<0.01, respectively). Left ventricular regional wall function and ejection fraction were not different between the two groups. CFR was significantly lower in group 1 than in group 2 (1.65+/-0.21 vs. 2.31+/-0.28, P<0.001). Gated SPECT MIBI and CFR had similar sensitivity (88 vs. 88%), specificity (80 vs. 84%), and accuracy (84 vs. 86%) for detecting CAD in patients with LBBB. The agreement between the two methods was 85%. Our results show comparable diagnostic utility and high agreement between gated SPECT MIBI perfusion imaging and TTDE CFR assessment for detecting CAD in patients with LBBB. The advantage of gated SPECT MIBI over TTDE CFR measurements is the ability to assess the perfusion abnormalities in multiple vascular territories during the same procedure, which is convenient for detecting multi-vessel disease in patients with LBBB.

Heme Oxygenase-1 Induction Improves Cardiac Function following Myocardial Ischemia by Reducing Oxidative Stress

PubMed Central

Issan, Yossi; Kornowski, Ran; Aravot, Dan; Shainberg, Asher; Laniado-Schwartzman, Michal; Sodhi, Komal; Abraham, Nader G.; Hochhauser, Edith

2014-01-01

Background Oxidative stress plays a key role in exacerbating diabetes and cardiovascular disease. Heme oxygenase-1 (HO-1), a stress response protein, is cytoprotective, but its role in post myocardial infarction (MI) and diabetes is not fully characterized. We aimed to investigate the protection and the mechanisms of HO-1 induction in cardiomyocytes subjected to hypoxia and in diabetic mice subjected to LAD ligation. Methods In vitro: cultured cardiomyocytes were treated with cobalt-protoporphyrin (CoPP) and tin protoporphyrin (SnPP) prior to hypoxic stress. In vivo: CoPP treated streptozotocin-induced diabetic mice were subjected to LAD ligation for 2/24 h. Cardiac function, histology, biochemical damage markers and signaling pathways were measured. Results HO-1 induction lowered release of lactate dehydrogenase (LDH) and creatine phospho kinase (CK), decreased propidium iodide staining, improved cell morphology and preserved mitochondrial membrane potential in cardiomyocytes. In diabetic mice, Fractional Shortening (FS) was lower than non-diabetic mice (35±1%vs.41±2, respectively p<0.05). CoPP-treated diabetic animals improved cardiac function (43±2% p<0.01), reduced CK, Troponin T levels and infarct size compared to non-treated diabetic mice (P<0.01, P<0.001, P<0.01 respectively). CoPP-enhanced HO-1 protein levels and reduced oxidative stress in diabetic animals, as indicated by the decrease in superoxide levels in cardiac tissues and plasma TNFα levels (p<0.05). The increased levels of HO-1 by CoPP treatment after LAD ligation led to a shift of the Bcl-2/bax ratio towards the antiapoptotic process (p<0.05). CoPP significantly increased the expression levels of pAKT and pGSK3β (p<0.05) in cardiomyocytes and in diabetic mice with MI. SnPP abolished CoPP's cardioprotective effects. Conclusions HO-1 induction plays a role in cardioprotection against hypoxic damage in cardiomyocytes and in reducing post ischemic cardiac damage in the diabetic heart as proved by the increased levels of pAKT with a concomitant inhibition of pGSK3β leading to preserved mitochondrial membrane potential. PMID:24658657

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

Hubbard, L; Ziemer, B; Lipinski, J

Purpose: To evaluate the accuracy of a low-dose, first-pass-analysis (FPA) dynamic computed tomography angiography and perfusion (CTAP) technique, for whole-organ anatomical and functional assessment of coronary artery disease (CAD). Methods: An angioplasty balloon was advanced into the left anterior descending (LAD) coronary artery of five swine (35–45 kg) to induce several levels of stenosis at maximal hyperemia (intracoronary adenosine, 240 µg/min). Reference fluorescence microspheres and intravenous contrast (370 mg/mL iodine, 25 mL, 7 mL/s) were injected centrally and dynamic imaging was performed using a 320-slice CT scanner at 100 kVp and 200 mA. Twenty volume scans were acquired per stenosismore » level to capture complete aortic and myocardial enhancement curves, but only two volume scans were used for whole-organ dynamic FPA CTAP measurement. All CTAP measurements in the LAD were compared to the reference microsphere perfusion measurements using linear regression, concordance correlation, and Bland-Altman analysis. Results: The result of dynamic FPA CTAP measurement in the LAD was in good agreement with the reference microsphere perfusion measurement (P-CTAP = 1.01 P-MICRO + 0.16, R{sup 2} = 0.95). The root mean square error (RMSE) and difference (RMSD) of measurement were 0.51 mL/min/g and 0.47 mL/min/g, respectively. Bland-Altman analysis demonstrated negligible systematic measurement bias. Additionally, the concordance correlation coefficient (CCC) was found to be ρ = 0.97, indicating excellent agreement between dynamic FPA CTAP measurement and the reference microsphere perfusion measurement. Lastly, the effective dose of the proposed technique using the “simulated” two-volume scan CTAP acquisition protocol was 2.6 mSv; much lower than the ∼10 mSv effective dose of current dynamic CTP techniques alone. Conclusion: The results indicate the potential for significant improvements in CAD assessment through low-dose, quantitative dynamic FPA CTAP. Such improvements are afforded through whole-organ CT scanning technology, and have the potential to improve patient outcomes and lead to healthier patient lives. Conflict of Interest (only if applicable): Grant funding from Toshiba America Medical Systems.« less

Time to Confront Willis's Lads with a Ballet Class? A Case Study of Educational Orthodoxy and White Working-Class Boys

ERIC Educational Resources Information Center

Ashley, Martin

2009-01-01

This is a retrospective study tracing the longer term effects on identity and aspiration of white working-class boys from an area of high social deprivation. The boys were members of an acclaimed boys' dance company and have been retrospectively interviewed as young men in their twenties. Documentary and film material dating from the time they…

"They Just Don't Seem to Really Care, They Just Think It's Cool to Sit There and Talk": Laddism in University Teaching-Learning Contexts

ERIC Educational Resources Information Center

Jackson, Carolyn; Dempster, Steve; Pollard, Lucie

2015-01-01

Over the last 2--3?years there has been a sharp increase in the UK in the number of concerns voiced about "laddism", "laddish" or "lad" cultures in higher education (HE). Drawing on a project that explored laddism on a sports science degree in one university, this article explores constructions and understandings of…

Left Internal Mammary Artery Usage in Coronary Artery Bypass Grafting: A Measure of Quality Control

PubMed Central

Karthik, S; Fabri, BM

2006-01-01

INTRODUCTION Over the last two decades, many studies have shown better long-term patency rates and survival in patients undergoing coronary artery bypass grafting (CABG) with left internal mammary artery (LIMA) to the left anterior descending artery (LAD). World-wide, LIMA is accepted as the ‘gold standard’ for surgical revascularisation and its usage has been steadily increasing. PATIENTS AND METHODS Between April 1997 and September 2001, a total of 4406 consecutive patients underwent coronary artery bypass grafting with revascularisation to the left anterior descending artery. RESULTS Of the study group, 4047 (91.8%) patients received LIMA to LAD, leaving 359 (8.2%) who did not. Six sub-groups of patients in whom LIMA usage was significantly less were the elderly (> 70 years of age), females, diabetics, patients having emergency CABG, poor left ventricular (LV) function (ejection fraction [EF] < 30%) and patients with respiratory disease. CONCLUSIONS Although the current focus in the UK is on mortality rates, we believe that it will not be long before this will also include the incidence of major morbidity after CABG such as stroke, myocardial infarction (MI), renal failure and sternal wound problems. We also believe that we should now consider LIMA usage as a marker of quality control after CABG. PMID:16834857

Recovering fNIRS brain signals: physiological interference suppression with independent component analysis

NASA Astrophysics Data System (ADS)

Zhang, Y.; Shi, M.; Sun, J.; Yang, C.; Zhang, Yajuan; Scopesi, F.; Makobore, P.; Chin, C.; Serra, G.; Wickramasinghe, Y. A. B. D.; Rolfe, P.

2015-02-01

Brain activity can be monitored non-invasively by functional near-infrared spectroscopy (fNIRS), which has several advantages in comparison with other methods, such as flexibility, portability, low cost and fewer physical restrictions. However, in practice fNIRS measurements are often contaminated by physiological interference arising from cardiac contraction, breathing and blood pressure fluctuations, thereby severely limiting the utility of the method. Hence, further improvement is necessary to reduce or eliminate such interference in order that the evoked brain activity information can be extracted reliably from fNIRS data. In the present paper, the multi-distance fNIRS probe configuration has been adopted. The short-distance fNIRS measurement is treated as the virtual channel and the long-distance fNIRS measurement is treated as the measurement channel. Independent component analysis (ICA) is employed for the fNIRS recordings to separate the brain signals and the interference. Least-absolute deviation (LAD) estimator is employed to recover the brain activity signals. We also utilized Monte Carlo simulations based on a five-layer model of the adult human head to evaluate our methodology. The results demonstrate that the ICA algorithm has the potential to separate physiological interference in fNIRS data and the LAD estimator could be a useful criterion to recover the brain activity signals.

Sleep-disordered breathing in patients with atrial fibrillation and normal systolic left ventricular function.

PubMed

Bitter, Thomas; Langer, Christoph; Vogt, Jürgen; Lange, Mathias; Horstkotte, Dieter; Oldenburg, Olaf

2009-03-01

Obstructive sleep apnea (OSA) is more common in patients with atrial fibrillation (AFib). Recently, an additional association between central sleep apnea/Cheyne-Stokes respiration (CSA/CSR) and AFib has been described. The aim of this study was to investigate the prevalence and type of sleep-disordered breathing in patients with AFib and normal systolic left ventricular function. 150 patients (110 men and 40 women, aged 66.1 +/- 1.7 years) underwent cardiorespiratory polygraphy, capillary blood gas analysis, measurement of NT-proBNP, and echocardiography to determine the diameter of the left atrium (LAD) and the peak systolic pulmonary artery pressure (PAP). Sleep-disordered breathing was documented in 74% of all patients with AFib (43% had OSA and 31% had CSA/CSR). Patients with CSA/CSR had a higher PAP, a higher apnea-hypopnea index, a greater LAD, and a lower capillary blood pCO(2) than patients with OSA. Patients with AFib were found to have not only a high prevalence of obstructive sleep apnea, as has been described previously, but also a high prevalence of CSA/CSR. It remains unknown whether CSA/CSR is more common in AFib because of diastolic dysfunction or whether phenomena associated with CSA/CSR predispose to AFib. Further research on this question is needed.

A Finite Element Study on Variations in Mass Transport in Stented Porcine Coronary Arteries Based on Location in the Coronary Arterial Tree

PubMed Central

Keyes, Joseph T.; Simon, Bruce R.; Vande Geest, Jonathan P.

2013-01-01

Drug-eluting stents have a significant clinical advantage in late-stage restenosis due to the antiproliferative drug release. Understanding how drug transport occurs between coronary arterial locations can better help guide localized drug treatment options. Finite element models with properties from specific porcine coronary artery sections (left anterior descending (LAD), right (RCA); proximal, middle, distal regions) were created for stent deployment and drug delivery simulations. Stress, strain, pore fluid velocity, and drug concentrations were exported at different time points of simulation (0–180 days). Tests indicated that the highest stresses occurred in LAD sections. Higher-than-resting homeostatic levels of stress and strain existed at upwards of 3. mm away from the stented region, whereas concentration of species only reached 2.7 mm away from the stented region. Region-specific concentration showed 2.2 times higher concentrations in RCA artery sections at times corresponding to vascular remodeling (peak in the middle segment) compared to all other segments. These results suggest that wall transport can occur differently based on coronary artery location. Awareness of peak growth stimulators and where drug accumulation occurs in the vasculature can better help guide local drug delivery therapies. PMID:23699720

Reliable porcine coronary model of chronic total occlusion using copper wire stents and bioabsorbable levo-polylactic acid polymer.

PubMed

Sim, Doo Sun; Jeong, Myung Ho; Cha, Kyoung Rae; Park, Suk Ho; Park, Jong Oh; Shin, Young Min; Shin, Heungsoo; Hong, Young Joon; Ahn, Youngkeun; Schwartz, Robert S; Kang, Jung Chaee

2012-12-01

Chronic total occlusion (CTO) remains a challenge in interventional cardiology. We investigated the feasibility and reliability of copper wire stents and levo-polylactic acid (l-PLA) as a means of CTO induction in a porcine model. In one group of 20 swine, copper stents were crimped on a 3.0mm angioplasty balloon and inserted into the mid-left anterior descending coronary artery (LAD). In the other group of 20 swine, l-PLA was wrapped on a guidewire and pushed into the distal LAD with a 3.0mm balloon catheter to induce embolization. Of 20 swine which underwent copper stent implantation, 13 died of stent thrombosis. In the remaining 7 swine, total or near total occlusion with collateral circulation was observed at 5 weeks. Of 20 swine which underwent l-PLA embolization, 4 died of ventricular fibrillation during or shortly after the procedure. Serial histopathologic studies showed complete absorption of the polymer with replacement by fibrotic tissue approximately 4 weeks following the polymer implantation. CTO could be reliably induced in porcine coronary arteries by copper stents and l-PLA. These models may support investigation of new percutaneous devices to facilitate CTO interventions. Copyright © 2012 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Interhospital air transport of a blind patient on extracorporeal life support with consecutive and successful left ventricular assist device implantation.

PubMed

Bauer, Adrian; Schaarschmidt, Jan; Grosse, F Oliver; Al Alam, Nidal; Hausmann, Harald; Krämer, Klaus; Strüber, Martin; Mohr, Friedrich W

2014-06-01

The use of extracorporeal life support systems (ECLS) in patients with postcardiotomy low cardiac output syndrome (LCO) as a bridge to recovery and bridge to implantation of ventricular assist device (VAD) is common nowadays. A 59-year-old patient with acute myocardial infarction received a percutaneous transluminal angioplasty and stenting of the circumflex artery. During catheterization of the left coronary artery (LAD), the patient showed ventricular fibrillation and required defibrillation and cardiopulmonary resuscitation. After implantation of an intra-aortic balloon pump, the patient immediately was transmitted to the operating room. He received emergency coronary artery bypass grafting in a beating heart technique using pump-assisted minimal extracorporeal circulation circuit (MECC). Two bypass grafts were performed to the LAD and the right posterior descending artery. Despite initial successful weaning off cardiopulmonary bypass with high-dose inotropic support, the patient presented postcardiotomy LCO and an ECLS was implanted. The primary setup of the heparin-coated MECC system was modified and used postoperatively. As a result of the absence of an in-house VAD program, the patient was switched to a transportable ECLS the next day and was transferred by helicopter to the nearest VAD center where the patient received a successful insertion of a left VAD 3 days later.

Atherosclerotic involvement in patients with left or right dominant coronary circulation.

PubMed

Balci, Bahattin; Yilmaz, Ozcan

2004-06-01

There are variations in the anatomy of the coronary arteries in patients with left dominant circulation. The influence of anatomical variations in patients with left dominant circulation on coronary arteriosclerosis is not clear. We investigated whether atherosclerotic involvement in patients with left dominant circulation differs from that in patients with right dominant circulation. We retrospectively compared 38 consecutive angiograms with left coronary dominance with 459 consecutive angiograms with right coronary dominance. By using the 29-segment coding system of the American College of Cardiology/American Heart Association, numerical values were given to each segment, according to the percentage of the decrease in luminary diameter. Using, the sum of numerical values in each coronary artery, LAD score, LCx score, RCA score, and left main coronary artery (LMCA) score were obtained. Using the sum of these 4 vessel scores, the coronary artery disease (CAD) score was calculated. Total LAD score (49+/-48 vs 47+/-57), total LCx score (29+/-45 vs 41+/-58), total RCA score (32+/-68 vs 30+/-51), total LMCA score (1.8+/-11.3 vs 2.9+/-13.6) and total CAD score (108+/-108 vs 108+/-123) were similar in patients with left and right dominant circulation (all differences NS). The extent of coronary atherosclerosis does not depend on the type of dominant coronary circulation.

Protective effects of circulating microvesicles derived from myocardial ischemic rats on apoptosis of cardiomyocytes in myocardial ischemia/reperfusion injury.

PubMed

Wang, Yao; Wei, Su; Wang, Yi-Lu; Liu, Miao; Shang, Man; Zhang, Qi; Wu, Yan-Na; Liu, Ming-Lin; Song, Jun-Qiu; Liu, Yan-Xia

2017-08-15

To investigate the effects of circulating microvesicles derived from myocardial ischemia (I-MVs) on apoptosis in myocardial ischemia/reperfusion (I/R) injury in rats. I-MVs from rats undergoing myocardial left anterior descending (LAD) coronary artery ligation were isolated by ultracentrifugation from circulating blood and characterized by flow cytometry. I-MVs were administered intravenously (4.8 mg/kg) at 5 min before reperfusion procedure in I/R injury model which was induced by 30-min of ischemia and 120-min of reperfusion of LAD in rats. Treatment with I-MVssignificantly reduced the size of myocardial infarction, the activities of serum CK-MB and LDH, and the number of apoptotic cardiomyocytes. The activities of caspase 3, caspase 9 and caspase 12 in myocardium were also decreased significantly with I-MVs treatment. Moreover, the expression of Bax was decreased but Bcl-2 was increased. The expression of glucose regulated protein 78 (GRP78), sarco/endoplasmic reticulum Ca 2+ -ATPase 2 (SERCA2) and phosphorylated phospholamban (p-PLB) were increased after being treated with I-MVs. I-MVs could protect hearts from I/R injury in rats through SERCA2 and p-PLB of calcium regulatory proteins to alleviate intrinsic myocardial apoptosis including mitochondrial and endoplasmic reticulum pathways.

Liquid Acquisition Strategies for Exploration Missions: Current Status 2010

NASA Technical Reports Server (NTRS)

Chato, David J.

2010-01-01

NASA is currently developing the propulsion system concepts for human exploration missions to the lunar surface. The propulsion concepts being investigated are considering the use of cryogenic propellants for the low gravity portion of the mission, that is, the lunar transit, lunar orbit insertion, lunar descent and the rendezvous in lunar orbit with a service module after ascent from the lunar surface. These propulsion concepts will require the vapor free delivery of the cryogenic propellants stored in the propulsion tanks to the exploration vehicles main propulsion system (MPS) engines and reaction control system (RCS) engines. Propellant management devices (PMD s) such as screen channel capillary liquid acquisition devices (LAD s), vanes and sponges currently are used for earth storable propellants in the Space Shuttle Orbiter OMS and RCS applications and spacecraft propulsion applications but only very limited propellant management capability exists for cryogenic propellants. NASA has begun a technology program to develop LAD cryogenic fluid management (CFM) technology through a government in-house ground test program of accurately measuring the bubble point delta-pressure for typical screen samples using LO2, LN2, LH2 and LCH4 as test fluids at various fluid temperatures and pressures. This presentation will document the CFM project s progress to date in concept designs, as well ground testing results.

Investigations on Laser Beam Welding of Different Dissimilar Joints of Steel and Aluminum Alloys for Automotive Lightweight Construction

NASA Astrophysics Data System (ADS)

Seffer, Oliver; Pfeifer, Ronny; Springer, André; Kaierle, Stefan

Due to the enormous potential of weight saving, and the consequential reduction of pollutant emissions, the use of hybrid components made of steel and aluminum alloys is increasing steadily, especially concerning automotive lightweight construction. However, thermal joining of steel and aluminum is still being researched, due to a limited solubility of the binary system of iron and aluminum causing the formation of hard and brittle intermetallic phases, which decrease the strength and the formability of the dissimilar seam. The presented results show the investigation of laser beam welding for joining different dissimilar hybrid components of the steel materials HX220LAD+Z100, 22MnB5+AS150 and 1.4301, as well as the aluminum alloy AA6016-T4 as a lap joint. Among other things, the influences of the energy per unit length, the material grade, the sheet thickness t, the weld type (lap weld, fillet weld) and the arrangement of the base materials in a lap joint (aluminum-sided irradiation, steel-sided irradiation) on the achievable strengths are analyzed. The characterization of the dissimilar joints includes tensile shear tests and metallographic analyses, depending on the energy per unit length.

Radioprotective Properties of Detoxified Lipid A from Salmonella minnesota R595

DTIC Science & Technology

1986-01-01

irradiated animals treated with bacterial endotoxins. Am. J. Physiol. 191, 124-130 (1957). 3. M. PARANT, Effect of LPS on nonspecific recistance to...Salmonella minnesota R595. Radiat. Res. 107, 107-114(1986). . in the past, the toxicity of bacterial lipopolysaccharide (LPS) or its principal bioactive...contained significantly less CSA than those receiving either GLY or LAD. DISCUSSION The radioprotective effect of bacterial endotoxins has been known for over

Ocean Wave Slope Statistics from Automated Analysis of Sun Glitter Photographs

DTIC Science & Technology

1985-06-01

8217*.... . .. , .. . .. I 1 SCONTROL MAPCROSSREF.LAdEf_ 2 Si4OuTINE HDSPLY ( HTST . No NAME. XO. XSTEPI 3 C 4 C SIUBROUTINE TO nISPLAY A UNIVARIATE HISTOGRAM...LYRANON. CSC, FESRUARV ?6s 1qA0. 7 C a C HTST z HISTOGRAM ARRAY. 9 C NT 0 ROW DIMFNSION OF HIST. to C N.1 x COLUMN DIMENSTnN OF MIST. it C 12 REAL HIST

The Large Observatory For X-ray Timing (LOFT): The ESA Mission and Proposed US Contributions

NASA Astrophysics Data System (ADS)

Ray, Paul S.; Feroci, M.; den Herder, J.; Bozzo, E.; Chakrabarty, D.; Wilson, C.; Consortium, LOFT; US-LOFT Collaboration

2013-04-01

High-time-resolution X-ray observations of compact objects provide direct access to strong-field gravity, to the equation of state of ultradense matter and to black hole masses and spins. A 10 m2-class instrument in combination with good spectral resolution is required to exploit the relevant diagnostics and answer fundamental questions about matter under extreme conditions. The Large Observatory For X-ray Timing (LOFT), selected by ESA as one of the four Cosmic Vision M3 candidate missions to undergo an assessment phase, will revolutionize the study of collapsed objects in our Galaxy and of the brightest supermassive black holes in active galactic nuclei. Thanks to an innovative design and the development of large-area monolithic silicon drift detectors, the Large Area Detector (LAD) on board LOFT will achieve an effective area of over 10 m2 (more than an order of magnitude larger than any spaceborne predecessor) in the 2-30 keV range (up to 50 keV in expanded mode), yet still fits in a conventional platform and medium-class launcher. With this large area and a spectral resolution of <260 eV, LOFT will yield unprecedented information on strongly curved spacetimes and matter under extreme conditions of pressure and magnetic field strength. A second instrument onboard LOFT, the Wide Field Monitor (WFM), will discover and localize X-ray transients and impulsive events and monitor spectral state changes with unprecedented sensitivity and coverage. Through the LOFT Burst Alert System (LBAS), locations and times of impulsive events discovered by the WFM will be relayed to the ground within about 30 seconds. In this talk, we will present an overview of the design and status of the LOFT mission and describe the proposed US contributions currently under evaluation by NASA. NRL participation in LOFT is funded by NASA.

TU-F-17A-06: Motion Stability and Dosimetric Impact of Spirometer-Based DIBH-RT of Left-Sided Breast Cancer

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

McKenzie, E; Yang, W; Burnison, M

2014-06-15

Purpose: Patients undergoing radiotherapy (RT) for left-sided breast cancer have increased risk of coronary artery disease. Deep Inhalation Breath Hold assisted RT (DIBH-RT) is shown to increase the geometric separation of the target area and heart, reducing cardiac radiation dose. The purposes of this study are to use Cine MV portal images to determine the stability of spirometer-guided DIBH-RT and examine the dosimetric cardiopulmonary impact of this technique. Methods: Twenty consecutive patients with left-sided breast cancer were recruited to the IRB-approved study. Free-breathing (FB) and DIBH-CT's were acquired at simulation. Rigid registration of the FB-CT and DIBH-CT was performed usingmore » primarily breast tissue. Treatment plans were created for each FB-CT and DIBH-CT using identical paired tangent fields with field-in-field or electronic compensation techniques. Dosimetric evaluation included mean and maximum (Dmax) doses for the left anterior descending artery (LAD), mean heart dose, and left lung V20. Cine MV portal images were acquired for medial and lateral fields during treatment. Analysis of Cine images involved chest wall segmentation using an algorithm developed in-house. Intra- and inter-fractional chest wall motion were determined through affine registration to the first frame of each Cine. Results: Dose to each cardiac structure evaluated was significantly (p<0.001) reduced with the DIBH plans. Mean heart dose decreased from 2.9(0.9–6.6) to 1.6(0.6–5.3) Gy; mean LAD dose from 16.6(3–43.6) to 7.4(1.7–32.7) Gy; and LAD Dmax from 35.4 (6.1–53) to 18.4(2.5–51.2) Gy. No statistically significant reduction was found for the left lung V20. Average AP and SI median chest wall motion (intrafractional) was 0.1 (SD=0.9) and 0.5 (SD=1.1) mm, respectively. Average AP inter-fractional chest wall motion was 2.0 (SD=1.4) mm. Conclusion: Spirometer-based DIBH treatments of the left breast are reproducible both inter- and intra-fractionally, and provide a statistically and potentially clinically useful dosimetric advantage to cardiac structures.« less

Retrieval of effective leaf area index (LAIe) and leaf area density (LAD) profile at individual tree level using high density multi-return airborne LiDAR

NASA Astrophysics Data System (ADS)

Lin, Yi; West, Geoff

2016-08-01

As an important canopy structure indicator, leaf area index (LAI) proved to be of considerable implications for forest ecosystem and ecological studies, and efficient techniques for accurate LAI acquisitions have long been highlighted. Airborne light detection and ranging (LiDAR), often termed as airborne laser scanning (ALS), once was extensively investigated for this task but showed limited performance due to its low sampling density. Now, ALS systems exhibit more competing capacities such as high density and multi-return sampling, and hence, people began to ask the questions like-;can ALS now work better on the task of LAI prediction?; As a re-examination, this study investigated the feasibility of LAI retrievals at the individual tree level based on high density and multi-return ALS, by directly considering the vertical distributions of laser points lying within each tree crown instead of by proposing feature variables such as quantiles involving laser point distribution modes at the plot level. The examination was operated in the case of four tree species (i.e. Picea abies, Pinus sylvestris, Populus tremula and Quercus robur) in a mixed forest, with their LAI-related reference data collected by using static terrestrial laser scanning (TLS). In light of the differences between ALS- and TLS-based LAI characterizations, the methods of voxelization of 3D scattered laser points, effective LAI (LAIe) that does not distinguish branches from canopies and unified cumulative LAI (ucLAI) that is often used to characterize the vertical profiles of crown leaf area densities (LADs) was used; then, the relationships between the ALS- and TLS-derived LAIes were determined, and so did ucLAIs. Tests indicated that the tree-level LAIes for the four tree species can be estimated based on the used airborne LiDAR (R2 = 0.07, 0.26, 0.43 and 0.21, respectively) and their ucLAIs can also be derived. Overall, this study has validated the usage of the contemporary high density multi-return airborne LiDARs for LAIe and LAD profile retrievals at the individual tree level, and the contribution are of high potential for advancing forest ecosystem modeling and ecological understanding.

Revision of orthovoltage chest wall treatment using Monte Carlo simulations.

PubMed

Zeinali-Rafsanjani, B; Faghihi, R; Mosleh-Shirazi, M A; Mosalaei, A; Hadad, K

2017-01-01

Given the high local control rates observed in breast cancer patients undergoing chest wall irradiation by kilovoltage x-rays, we aimed to revisit this treatment modality by accurate calculation of dose distributions using Monte Carlo simulation. The machine components were simulated using the MCNPX code. This model was used to assess the dose distribution of chest wall kilovoltage treatment in different chest wall thicknesses and larger contour or fat patients in standard and mid sternum treatment plans. Assessments were performed at 50 and 100 cm focus surface distance (FSD) and different irradiation angles. In order to evaluate different plans, indices like homogeneity index, conformity index, the average dose of heart, lung, left anterior descending artery (LAD) and percentage target coverage (PTC) were used. Finally, the results were compared with the indices provided by electron therapy which is a more routine treatment of chest wall. These indices in a medium chest wall thickness in standard treatment plan at 50 cm FSD and 15 degrees tube angle was as follows: homogeneity index 2.57, conformity index 7.31, average target dose 27.43 Gy, average dose of heart, lung and LAD, 1.03, 2.08 and 1.60 Gy respectively and PTC 11.19%. Assessments revealed that dose homogeneity in planning target volume (PTV) and conformity between the high dose region and PTV was poor. To improve the treatment indices, the reference point was transferred from the chest wall skin surface to the center of PTV. The indices changed as follows: conformity index 7.31, average target dose 60.19 Gy, the average dose of heart, lung and LAD, 3.57, 6.38 and 5.05 Gy respectively and PTC 55.24%. Coverage index of electron therapy was 89% while it was 22.74% in the old orthovoltage method and also the average dose of the target was about 50 Gy but in the given method it was almost 30 Gy. The results of the treatment study show that the optimized standard and mid sternum treatment for different chest wall thicknesses is with 50 cm FSD and zero (vertical) tube angle, while in large contour patients, it is with 100 cm FSD and zero tube angle. Finally, chest wall kilovoltage and electron therapies were compared, which revealed that electron therapy produces a better dose distribution than kilovoltage therapy.

Myocardial dimensions and hemodynamics during 24-h ultraendurance ergometry.

PubMed

Pokan, Rochus; Ocenasek, Helmuth; Hochgatterer, Rainer; Miehl, Martin; Vonbank, Karin; Von Duvillard, Serge P; Franklin, Barry; Würth, Sabine; Volf, Ivo; Wonisch, Manfred; Hofmann, Peter

2014-02-01

This study aimed to evaluate cardiorespiratory and hemodynamic responses during 24 h of continuous cycle ergometry in ultraendurance athletes. Eight males (mean ± SD; age = 39 ± 8 yr, height = 179 ± 7 cm, body weight [Wt] = 77.1 ± 6.0 kg) were monitored during 24 h at a constant workload,∼25% below the first lactate turn point at 162 ± 23 W. Measurements included Wt, HR, oxygen consumption (V˙O2), cardiac output (Q), and stroke volume (SV) determined by a noninvasive rebreathing technique (Innocor; Innovision, Odense, Denmark). Myocardial dimensions were evaluated using a two-dimensional echocardiogram. [M-mode measurement]-left atrial (LAD), ventricular end-diastolic (LVEDD), and end-systolic diameters (LVESD) were obtained over the left parasternal area. Venous blood samples were analyzed for hematocrit (Hct%), albumin (g·L(-1)), aldosterone (pg·mL(-1)), CK, CK-MB (U·L(-1)), and N-terminal pro-brain natriuretic peptide (NT-proBNP) (pg·mL(-1)). HR (bpm) significantly increased (P < 0.01) from 1 h (132 ± 11) to 6 h (143 ± 10) and significantly decreased (P < 0.001) from 6 to 24 h (116 ± 10). V˙O2 and (Q were unchanged during the 24 h. Wt (76.6 ± 5.6 vs 78.7 ± 5.4), SV (117 ± 13 vs 148 ± 19), LVEDD (4.9 ± 0.3 vs 5.6 ± 0.2), and LAD (3.6 ± 0.5 vs 4.3 ± 0.7) significantly increased between 6 and 24 h (P < 0.001). No significant changes were observed for LVESD. Hct (45.1 ± 1.3 vs 41.3 ± 1.2) significantly decreased (P < 0.05) and CK (181 ± 60/877 ± 515), aldosterone (48 ± 17 vs 661 ± 172), and NT-proBNP (23 ± 13 vs 583 ± 449) significantly increased (P < 0.05). The increase in SV (ΔSV) was significantly related to changes in Wt (ΔWt), and HR (ΔHR) and ΔWt were significantly related to ΔLAD and ΔLVEDD. Our findings suggest that the decrease in HR during 24 h of ultraendurance exercise was due to hypervolemia and the associated ventricular loading, increasing left ventricular diastolic dimensions because of increased SV and LVEDD, resulting in an increase in NT-proBNP.

A Guide to the Estimation of the Hazard Presented by Chemicals in Human Milk.

DTIC Science & Technology

1985-11-01

Occupational and Environmental Health Laboratory Aerospace Medical Division (AFSC) Brooks Air Force Base , Texas 78235-5501 i "-_,-..,,," ,_. .,..,;.: 1...AD-RISS 651 A GUIDE TO THE ESTIMATION OF THE HZRR PRESENTED BY CHEMICALS IN HUMAN M.. (U) AIR FORCE OCCUPATIONAL ANo ENYIRONMENTAL HEALTH LAD BROOKS...illustration purposes and does not constitute endorsement or recommendation for use by the United States Air Force . Do not return this copy. Retain or

An Interactive Activation Model of the Effect of Context in Perception. Part I.

DTIC Science & Technology

1980-05-15

interested in word perception (Adams, 1979; Estes, 1975; LaBerge & Samuels, 1974; Johnston & McClelland, in press; McClelland, 1976). Our model differs from... LaBerge , D., & Samuels, S. Toward a theory of automatic information process- ing in -eading. Cognitive Psychology, 1974, 6, 293-323. Levin, J. A...Frederick Hayes-Roth I DR. ALBERT STEVENS Stanford University The lad Corporation BOLT BRINEX 4 NEWMAN, INC. Stanford, CA 94305 1700 Main Street 50

Manufacturing Methods and Technology for Digital Fault Isolation of Hybrid Microelectronic Assemblies.

DTIC Science & Technology

1982-03-01

Aircraft Company ARECAaSOENT CSR Ground Systems Group Task 007 Fullerton, California 92634 Project No. R1023 I$. =OTRS4.IWmOr SP NAnE lAD ABDASE it. REPORT...HMA feed mechanism, multiple type test sockets or adapters, and a localized UUT vessel for functional tests at temperature. The engineering model AP...test excluding (deactivated) microprocessor. * Models UUT and test adapter as a ROM. Independent latches or registers from interconnecting ports to

Area Handbook Series. Pakistan: A Country Study,

DTIC Science & Technology

1983-10-01

economic. national security, political, and social systems and institutions and ex - amining the interrelationshins of those systems and institutions...people of Paklsten. For example . the reade wil lAd um.a rather than Ramadan, ,eyd rather than ,md, s." r.athe dn ,aykh. kkod rather da Iud. and em rather...aUend the Constitution to mawe the o11e of the presidency the most powerful post of jsvernmeet (see Ensevgn Political System. ch. 4). He also anounced

Compilation of Abstracts of Theses Submitted by Candidates for Degrees

DTIC Science & Technology

1985-09-30

University of Maine, 1973 Patricia A. Ohmiel Lieutenant, Unitod States Navy B.A., College of Our Lad./ of the Elms , 1973 The purpose of this thesis...B.A., Slippery Rock State ,Collee, 1968 M.A., Western Michigan University, 1976 The thesis presnets a theoretical development of a definition of...United States Air Force 9.S. Slippery Rock State College, 1971 This paper is an examination of the Romanian economy. It begins with a basic description

Impact of 3D Canopy Structure on Remote Sensing Vegetation Index and Solar Induced Chlorophyll Fluorescence

NASA Astrophysics Data System (ADS)

Zeng, Y.; Berry, J. A.; Jing, L.; Qinhuo, L.

2017-12-01

Terrestrial ecosystem plays a critical role in removing CO2 from atmosphere by photosynthesis. Remote sensing provides a possible way to monitor the Gross Primary Production (GPP) at the global scale. Vegetation Indices (VI), e.g., NDVI and NIRv, and Solar Induced Fluorescence (SIF) have been widely used as a proxy for GPP, while the impact of 3D canopy structure on VI and SIF has not be comprehensively studied yet. In this research, firstly, a unified radiative transfer model for visible/near-infrared reflectance and solar induced chlorophyll fluorescence has been developed based on recollision probability and directional escape probability. Then, the impact of view angles, solar angles, weather conditions, leaf area index, and multi-layer leaf angle distribution (LAD) on VI and SIF has been studied. Results suggest that canopy structure plays a critical role in distorting pixel-scale remote sensing signal from leaf-scale scattering. In thin canopy, LAD affects both of the remote sensing estimated GPP and real GPP, while in dense canopy, SIF variations are mainly due to canopy structure, instead of just due to physiology. At the microscale, leaf angle reflects the plant strategy to light on the photosynthesis efficiency, and at the macroscale, a priori knowledge of leaf angle distribution for specific species can improve the global GPP estimation by remote sensing.

MacroH2A1 associates with nuclear lamina and maintains chromatin architecture in mouse liver cells.

PubMed

Fu, Yuhua; Lv, Pin; Yan, Guoquan; Fan, Hui; Cheng, Lu; Zhang, Feng; Dang, Yongjun; Wu, Hao; Wen, Bo

2015-11-25

In the interphase nucleus, chromatin is organized into three-dimensional conformation to coordinate genome functions. The lamina-chromatin association is important to facilitate higher-order chromatin in mammalian cells, but its biological significances and molecular mechanisms remain poorly understood. One obstacle is that the list of lamina-associated proteins remains limited, presumably due to the inherent insolubility of lamina proteins. In this report, we identified 182 proteins associated with lamin B1 (a constitutive component of lamina) in mouse hepatocytes, by adopting virus-based proximity-dependent biotin identification. These proteins are functionally related to biological processes such as chromatin organization. As an example, we validated the association between lamin B1 and core histone macroH2A1, a histone associated with repressive chromatin. Furthermore, we mapped Lamina-associated domains (LADs) in mouse liver cells and found that boundaries of LADs are enriched for macroH2A. More interestingly, knocking-down of macroH2A1 resulted in the release of heterochromatin foci marked by histone lysine 9 trimethylation (H3K9me3) and the decondensation of global chromatin structure. However, down-regulation of lamin B1 led to redistribution of macroH2A1. Taken together, our data indicated that macroH2A1 is associated with lamina and is required to maintain chromatin architecture in mouse liver cells.

Multiple left anterior descending coronary artery to left ventricular fistula - A case series and literature review.

PubMed

Iyer, Praneet; Yelisetti, Rishitha

2017-10-01

Coronary artery fistulas (CAFs) are found in 0.3-0.8% of patients who undergo coronary angiography. CAFs are defined as single or multiple, small or large direct communications that arise from one or more coronary arteries and enter into one of the four cardiac chambers or major vessels. We present two cases of multiple coronary artery fistulas arising from diagonal and left anterior descending (LAD) branches of left coronary artery draining into the left ventricle. In both the cases, No intervention was performed. Of the congenital fistulas, two major groups are identified: solitary CAFs or coronary artery-left ventricular multiple micro-fistulas (CALVMMFs). Noninvasive techniques such as transthoracic echocardiography, transesophageal echocardiography and magnetic resonance imaging are becoming increasingly popular for diagnosis and follow-up of CAFs. Despite the advent of these newer non-invasive modalities, coronary angiography remains the gold standard for diagnosis. Treatment of CAFs is indicated when the patients are symptomatic with left ventricular volume overload, myocardial ischemia, left ventricular dysfunction or in the presence of a large or increasing left-to-right shunt. If the fistula is small and hemodynamically insignificant, it can be managed with conservative management. Multiple left anterior descending to left ventricle (LV) fistulas are extremely rare and, as per our literature review, we noted only a few case reports of coronary artery fistulas between branches of LAD and left ventricle.

A mechanical argument for the differential performance of coronary artery grafts.

PubMed

Prim, David A; Zhou, Boran; Hartstone-Rose, Adam; Uline, Mark J; Shazly, Tarek; Eberth, John F

2016-02-01

Coronary artery bypass grafting (CABG) acutely disturbs the homeostatic state of the transplanted vessel making retention of graft patency dependent on chronic remodeling processes. The time course and extent to which remodeling restores vessel homeostasis will depend, in part, on the nature and magnitude of the mechanical disturbances induced upon transplantation. In this investigation, biaxial mechanical testing and histology were performed on the porcine left anterior descending artery (LAD) and analogs of common autografts, including the internal thoracic artery (ITA), radial artery (RA), great saphenous vein (GSV) and lateral saphenous vein (LSV). Experimental data were used to quantify the parameters of a structure-based constitutive model enabling prediction of the acute vessel mechanical response pre-transplantation and under coronary loading conditions. A novel metric Ξ was developed to quantify mechanical differences between each graft vessel in situ and the LAD in situ, while a second metric Ω compares the graft vessels in situ to their state under coronary loading. The relative values of these metrics among candidate autograft sources are consistent with vessel-specific variations in CABG clinical success rates with the ITA as the superior and GSV the inferior graft choices based on mechanical performance. This approach can be used to evaluate other candidate tissues for grafting or to aid in the development of synthetic and tissue engineered alternatives. Copyright © 2015 Elsevier Ltd. All rights reserved.

Small vessel hematocrit in ischemic myocardium

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

Gumm, D.C.; Cooper, S.M.; Marcus, M.L.

1986-03-01

As blood enters the microvasculature of normally perfused myocardium, there is a progressive decrease in small vessel hematocrit (SV Hct) due to RBC streaming in smaller branching vessels and the Fahraeus-Lindqvist effect. We hypothesized that if the coronary collateral circulation was composed of very small vessels branching from large parent vessels, plasma streaming would result in a further decrease of SV Hct in ischemic myocardium. Six open chest anesthetized dogs were studied. Plasma was labelled with /sup 59/FeCl siderophilin and RBC's with /sup 99/mTc to estimate SV Hct from myocardial biopsies. The LAD was occluded and cannulated for measurement ofmore » retrograde flow (arising presumably from proximal collaterals). The ischemic region was identified using the microsphere shadow technique. Collateral flow after LAD occlusion was 30 +- 12 ml/min 100g (x +- SE). Systemic Hct was 40 +- 1%. The Hct of blood from retrograde flow was 39 +- 1% (p = NS). Activity of /sup 59/FeCl and /sup 99/mTc in known quantities of blood were compared to myocardial biopsies to estimate SV Hct. Ischemic SV Hct was 23 +- 2% and non-ischemic SV Hct was 21 +- 1% (p = NS). We conclude that the size and branching pattern of coronary collaterals is such that plasma streaming in collaterals does not result in an additional decrease in SV Hct in ischemic myocardium.« less

SLAM family member 8 is involved in oncogenic KIT-mediated signaling in human mastocytosis.

PubMed

Sugimoto, Akihiko; Kataoka, Tatsuki R; Ueshima, Chiyuki; Takei, Yusuke; Kitamura, Kyohei; Hirata, Masahiro; Nomura, Takashi; Haga, Hironori

2018-03-02

The signaling lymphocytic activation molecule family member 8 (SLAMF8)/CD353 is a member of the CD2 family of proteins. Its ligand has not been identified. SLAMF8 is expressed by macrophages and suppresses cellular functions. No study has yet explored SLAMF8 expression or function in human mastocytosis, which features oncogenic KIT-mediated proliferation of human mast cells. SLAMF8 protein was expressed in human mastocytosis cells, immunohistochemically. SLAMF8 expression was also evident in the human mast cell lines, HMC1.2 (expressing oncogenic KIT) and LAD2 (expressing wild-type KIT) cells. SLAMF8-knockdown significantly reduced the KIT-mediated growth of HMC1.2 cells but not that of LAD2 cells. SLAMF8-knockdown HMC1.2 cells exhibited significant attenuation of SHP-2 activation and oncogenic KIT-mediated RAS-RAF-ERK signaling. An interaction between SLAMF8 and SHP-2 was confirmed in HMC1.2 cells and all pathological mastocytosis specimens examined (19 of 19 cases, 100%). Thus, SLAMF8 is involved in oncogenic KIT-mediated RAS-RAF-ERK signaling and the subsequent growth of human neoplastic mast cells mediated by SHP-2. SLAMF8 is a possible therapeutic target in human mastocytosis patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

A dosimetric study of cardiac dose sparing using the reverse semi-decubitus technique for left breast and internal mammary chain irradiation.

PubMed

Niglas, Mark; McCann, Claire; Keller, Brian M; Makhani, Nadiya; Presutti, Joseph; Vesprini, Danny; Rakovitch, Eileen; Elzibak, Alyaa; Mashouf, Shahram; Lee, Justin

2016-01-01

Breath-hold techniques can reduce cardiac dose in breast radiotherapy. The reverse semi-decubitus (RSD) technique is an alternative free-breathing method used at our centre. This study compares the dosimetry of free-breathing supine, RSD and moderate deep inspiration breath-hold (mDIBH) techniques. Twelve patients with left-sided breast cancer who were simulated using standard supine, RSD and mDIBH techniques were identified retrospectively. New plans using standard breast tangents and techniques for internal mammary chain (IMC) nodal coverage were assessed. Using standard tangents, mean heart dose, heart V25Gy and mean left anterior descending artery (LAD) dose were found to be significantly lower for RSD and mDIBH when compared to free-breathing supine (p ⩽ 0.03). Using wide-tangents, the maximum LAD point dose was also lower for RSD and mDIBH (p ⩽ 0.02). There were no statistically significant dosimetric differences found between the RSD and mDIBH simulation techniques for standard breast-tangent plans, though organ-at-risk doses were lower for mDIBH in wide-tangent plans. There was no improvement in cardiac dosimetry between RSD and free-breathing supine when using an electron field IMC plan. For patients unable to tolerate breath-hold, the RSD technique is an alternative approach that can reduce cardiac dose. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Crystal Structure and Oligomeric State of the RetS Signaling Kinase Sensory Domain

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

Jing, X.; Jaw, J; Robinson, H

2010-01-01

The opportunistic pathogen Pseudomonas aeruginosa may cause both acute and chronic-persistent infections in predisposed individuals. Acute infections require the presence of a functional type III secretion system (T3SS), whereas chronic P. aeruginosa infections are characterized by the formation of drug-resistant biofilms. The T3SS and biofilm formation are reciprocally regulated by the signaling kinases LadS, RetS, and GacS. RetS downregulates biofilm formation and upregulates expression of the T3SS through a unique mechanism. RetS forms a heterodimeric complex with GacS and thus prevents GacS autophosphorylation and downstream signaling. The signals that regulate RetS are not known but RetS possesses a distinctive periplasmicmore » sensor domain that is believed to serve as receptor for the regulatory ligand. We have determined the crystal structure of the RetS sensory domain at 2.0 {angstrom} resolution. The structure closely resembles those of carbohydrate binding modules of other proteins, suggesting that the elusive ligands are likely carbohydrate moieties. In addition to the conserved beta-sandwich structure, the sensory domain features two alpha helices which create a unique surface topology. Protein-protein crosslinking and fluorescence energy transfer experiments also revealed that the sensory domain dimerizes with a dissociation constant of K{sub d} = 580 {+-} 50 nM, a result with interesting implications for our understanding of the underlying signaling mechanism.« less

Lipofection of plasmid DNA into human mast cell lines using lipid nanoparticles generated by microfluidic mixing.

PubMed

Duguay, Brett A; Huang, Kate Wei-Chen; Kulka, Marianna

2018-04-18

Mast cells are important immune cells that have significant roles in mediating allergy and asthma. Therefore, studying the molecular mechanisms regulating these and other processes in mast cells is important to elucidate. Methods such as lipofection, transduction, and electroporation are often employed to dissect these mechanisms by disrupting gene expression in mast cell lines. However, as with other leukocytes, human mast cells (HMCs) are often refractory to the delivery of plasmids by lipofection. In this study, we investigated the utility of lipid nanoparticles (LNPs) containing the ionizable cationic lipids 1,2-dioleoyloxy-3-dimethylaminopropane, 1,2-dioleyloxy-3-dimethylaminopropane, or 2,2-dilinoleyl-4-(2-dimethylaminoethyl)-[1,3]-dioxolane for the delivery of plasmid DNA into HMC lines. Herein, we demonstrate for the first time the use of LNPs to achieve significant and reproducible levels of plasmid DNA transfection in HMC-1.2 and laboratory of allergic diseases 2 (LAD2) cells. These levels reached 53.2% and 16.0% in HMC-1.2 and LAD2 cells, respectively; and outperformed Lipofectamine 3000 in both cases. Moreover, cell viability in the transfected cells remained above 65% for all LNP conditions tested. Together, these observations illustrate the efficacy of this technique for mast cell researchers and further support the use of LNPs for nucleic acid delivery into leukocytes. ©2018 Society for Leukocyte Biology.

Conventional Weapons Effects on Reinforced Soil Walls.

DTIC Science & Technology

1995-03-01

parametric study of the influence of specific design variables on wall panel response. D. METHODOLOGY A single degree of freedom model was modified to...t. dAev AVoF design methodologies for reinforced soil subjected o bl...at lad, LM, r..s.o.s. of these systems to such loading must be established...for many years and then on short notice be shipped to a location for use. The design for this shelter would be done as needed, although some non -site

Perspectives on Reserve Attrition

DTIC Science & Technology

1988-10-01

potential differ- ences between Junior Enlisted, NCOs, and Junior Officers. How- ever, these data are likely to be most valuable when viewed as one...w I C4 1. I4 -4 1 44 1 E-1 I- E-44I - -44 g z-. 4-) P E 4) I - - W r.- Ix~ o I >4E-4~ 0 a4OE-4 ~ I4 4 >4E-4 1 ladO I 0 IM -4I ~E- H E4~ r. 9 E-4O W4 I

Light Augmentation Device: A New Surgical Tool for Improved Laparoscopic Visibility and Transillumination: Proof-of-Concept Study.

PubMed

Asti, Emanuele; Nebbia, Fabio; Sironi, Andrea; Bottino, Vincenzo; Bonitta, Gianluca; Bonavina, Luigi

2016-12-01

The light augmentation device (LAD ® ) is a new disposable tool designed to improve observation by transillumination in laparoscopic surgery. It can be introduced into the abdomen through an 11-12 mm port as a supplementary light source. The miniaturized design allows the surgeon to pick up the device with an endograsper and to place it under direct vision where needed. This proof-of-concept study demonstrated safety and efficacy of the device in the animal model.

Comparative Anthropometry of the Hand

DTIC Science & Technology

1980-12-01

presented in a report by Churchill, Kuby , and Daniels (1957)." The basic data used for men were those obtained in a survey of 4063 USAF flying personnel...Wright-Patterson Air Force Base, Ohio, December 1956. (AD 110 589) 6 Churchill, E., A. Kuby , and G. S. Daniels. Nomograph of the Hand and Its Related...LAD A047 314) 6. Churchill, E., A. Kuby , and G.S. Daniels. Nomograph of the Hand and Its Related Dimensions. WADC Technical Report 57-198, Wright Air

How should I treat a patient to remove a fractured jailed side branch wire?

PubMed

Owens, Colum G; Spence, Mark S

2011-08-01

A 53-year-old female was sent for diagnostic angiography after successful reperfusion therapy for an anterior ST-elevation myocardial infarct. The culprit lesion was a LAD/D1 bifurcation stenosis. Coronary angiography, intravascular ultrasound. Left anterior descending artery/first diagonal artery bifurcation stenosis, fractured jailed side branch wire. Provisional stenting strategy for bifurcation stenosis. Consideration of surgical and percutaneous options to retrieve fractured, jailed, side branch wire. Wire and balloon catheter wrap technique for retrieval of fractured wire.

Needs-Based Programs: Eligibility and Benefit Factors.

DTIC Science & Technology

1986-07-01

of m- Allm Veto= Nwftal Famt- Dim- IbWAd- amw- -m SSM - f~l dd __ s Bt p !Iidtt a m ablt Wind a aftim Ya LAWr Ibsh laD adi Grata 1 I I 1 I Pasta " I I...administration* refers to the level of government or the organization level responsible for day-to-day program administration. When "state" is shown...preschool program health, educational, nutri- are primarily for young offers educational, tional, social and other children (ages 3 to that age dental

Setting the Context: Suppression of Enemy Air Defenses and Joint War Fighting in an Uncertain World

DTIC Science & Technology

1994-06-01

indicate, ironically, that the greatest suppression element the Wild Weasel possessed was psychological .9 As much as 95 percent of its effectiveness may...extravagant spending on the latest Soviet LAD systems-made them invulnerable to attack by the Americans, or a belief that the United States was bluffing . What...ARMS may have on the enemy that outweigh system Pk (i.e ., psychological warfare against enemy site operators via intimidation). Methods ofAnalysis In

ADST System Test Report for the Rotary Wing Aircraft Airnet Aeromodel and Weapon Model Merge with the ATAC 2 Baseline

DTIC Science & Technology

1994-01-20

Category 2 - Investigation/Debug Required ..................................... 11 Table 3-1 Field Test Report Status/Corrective Action...in Table 3-1 in section 3.1. The Field Test Reports and SP/CR’s are listed below for the two categories: Table 3.0-1. Category 1 - LADS PMO Direction...symbology, consisting Wing Aircraft of the laser code A - H plus the four digit data field shall be displayed for 10 seconds, after which time only

Acoustic Metadata Management and Transparent Access to Networked Oceanographic Data Sets

DTIC Science & Technology

2011-09-30

Roberts in Pat Halpin’s lab, integrating the Marine Geospatial Ecology (GeoEco) toolset into our database services. While there is a steep...noise bands. The lower box at each site denotes the 1-6 kHz band while the upper box denotes 6-96 kHz band. Lad seamount has deployments at two sites...N00014-11-1-0697 http://cetus.ucsd.edu Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of

The development of methods for primary mast cells in vitro and ex vivo: An historical review.

PubMed

Yu, Tian-Yu; He, Zhi-Gang; Yang, Mu-Qing; Song, Jian; Ma, Cheng; Ma, Sun-Qiang; Feng, Jun-Lan; Bin Liu; Wang, Xiao-Dong; Li, Ji-Yu; Wei, Zhu-Bo

2018-05-26

Mast cells (MCs) are tissue-based stationary effector cells that form the immune system's first-line defense against various challenges. They are developed from the bone marrow-derived progenitors to complete their differentiation and maturation in the tissues where they eventually establish residence. MCs have been implicated in many diseases, such as allergy, parasitic infection, and neoplastic disorders. Immortalized MC lines, such as RBL-2H3, HMC-1, and LAD-2, are useful for investigating the biological functions of MC only to some extents due to the restriction of degranulation evaluation, in vivo injection and other factors. Over the past few decades, technologies for acquiring primarily MCs have been continually optimized, and novel protocols have been proposed. However, no relevant publications have analyzed and summarized these techniques. In this review, the classical approaches for extracting MCs are generalized, and new methods with potential values are introduced. We also evaluate the advantages and applicability of diverse MC models. Since MCs exhibit substantial plasticity and functional diversity due to different origins, it is both necessary and urgent to select a reliable and suitable source of MCs for a particular study. Copyright © 2018 Elsevier Inc. All rights reserved.

Regional inversion of GRACE data for continental water mass time-variations. Comparison with global hydrology models, classical spherical harmonics and "mascons" solutions

NASA Astrophysics Data System (ADS)

Seoane, L.; Ramillien, G.; Frappart, F.; Biancale, R.; Gratton, S.; Bourgogne, S.

2010-12-01

Time series of 2°-by-2° constrained/unconstrained GRACE geoid solutions have been computed with a 10-day resolution by using a new regional method recently implemented at GRGS (Toulouse, France). This approach uses the dynamical orbit analysis of GRACE Level-1 measurements, and specially accurate along-track KBRR residuals to estimate the continental water mass changes over large geographical regions. For validation, our GRACE-derived regional maps are compared to: (1) the global hydrological model outputs (WGHM, LaD, NOAH), (2) the NASA "mascons" solutions based on spherical harmonics and (3) the global solutions produced by GRGS and CSR, GFZ, JPL filtered with different methodologies (Gaussian, destriped and smoothed, ICA). In this study, we focus on the annual time scale of water mass redistributions occuring in drainage basins like Amazon or Congo. Each 2°-averaged surface element is characterized by its seasonal amplitude and phase. Even if the all sources are expected to provide quite comparable results for the continental water cycle, we suspect the residual differences are from smoothing effects of the spatial constraints included in the "mascons" solutions and the underestimating the seasonal amplitudes by global hydrological models.

Screening for Psychopathology Versus Selecting for Suitability: Ethical and Legal Considerations

NASA Technical Reports Server (NTRS)

Holland, Albert W.; Galarza, Laura; Arvey, Richard; Hysong, Sylvia; Sackett, Paul; Cascio, Wayne

2000-01-01

The current system for psychological selection of U.S. astronauts is divided into two phases: The select-out phase and the select-in phase. The select-out phase screens candidates for psychopathology; candidates who do not meet the baseline psychiatric requirements are immediately disqualified. The select-in phase assesses candidates for suitability to fly short- and long-duration missions. Suitability ratings are given for ten factors found to be critical for short and long-duration space missions. There are qualitative differences in the purpose of the two phases (select-in vs. select-out) and in the nature of the information collected in each phase. Furthermore, there are different logistic, ethical, and legal issues related to a medical or psychiatric (select-out) screening versus a suitability (select-in) psychological screening process . The purpose of this presentation is to contrast the ethical and legal environment surrounding the select-out and select-in phases of the psychological selection system. Issues such as data collection, data storage and management, the federal statutory environment, and personnel training will be discussed. Further, a summary of the new standards for psychological testing is presented, along with their implications for astronaut selection.

Accurate determination of high-risk coronary lesion type by multidetector cardiac computed tomography.

PubMed

Alasnag, Mirvat; Umakanthan, Branavan; Foster, Gary P

2008-07-01

Coronary arteriography (CA) is the standard method to image coronary lesions. Multidetector cardiac computerized tomography (MDCT) provides high-resolution images of coronary arteries, allowing a noninvasive alternative to determine lesion type. To date, no studies have assessed the ability of MDCT to categorize coronary lesion types. The objective of this study was to determine the accuracy of lesion type categorization by MDCT using CA as a reference standard. Patients who underwent both MDCT and CA within 2 months of each other were enrolled. MDCT and CA images were reviewed in a blinded fashion. Lesions were categorized according to the SCAI classification system (Types I-IV). The origin, proximal and middle segments of the major arteries were analyzed. Each segment comprised a data point for comparison. Analysis was performed using the Spearman Correlation Test. Four hundred eleven segments were studied, of which 110 had lesions. The lesion distribution was as follows: 35 left anterior descending (LAD), 29 circumflex (Cx), 31 right coronary artery (RCA), 2 ramus intermedius, 8 diagonal, 4 obtuse marginal and 2 left internal mammary arteries. Correlations between MDCT and CA were significant in all major vessels (LAD, Cx, RCA) (p < 0.001). The overall correlation coefficient was 0.67. Concordance was strong for lesion Types II-IV (97%) and poor for Type I (30%). High-risk coronary lesion types can be accurately categorized by MDCT. This ability may allow MDCT to play an important noninvasive role in the planning of coronary interventions.

A radiosity model for heterogeneous canopies in remote sensing

NASA Astrophysics Data System (ADS)

GarcíA-Haro, F. J.; Gilabert, M. A.; Meliá, J.

1999-05-01

A radiosity model has been developed to compute bidirectional reflectance from a heterogeneous canopy approximated by an arbitrary configuration of plants or clumps of vegetation, placed on the ground surface in a prescribed manner. Plants are treated as porous cylinders formed by aggregations of layers of leaves. This model explicitly computes solar radiation leaving each individual surface, taking into account multiple scattering processes between leaves and soil, and occlusion of neighboring plants. Canopy structural parameters adopted in this study have served to simplify the computation of the geometric factors of the radiosity equation, and thus this model has enabled us to simulate multispectral images of vegetation scenes. Simulated images have shown to be valuable approximations of satellite data, and then a sensitivity analysis to the dominant parameters of discontinuous canopies (plant density, leaf area index (LAI), leaf angle distribution (LAD), plant dimensions, soil optical properties, etc.) and scene (sun/ view angles and atmospheric conditions) has been undertaken. The radiosity model has let us gain a deep insight into the radiative regime inside the canopy, showing it to be governed by occlusion of incoming irradiance, multiple scattering of radiation between canopy elements and interception of upward radiance by leaves. Results have indicated that unlike leaf distribution, other structural parameters such as LAI, LAD, and plant dimensions have a strong influence on canopy reflectance. In addition, concepts have been developed that are useful to understand the reflectance behavior of the canopy, such as an effective LAI related to leaf inclination.

THE REAL ESTATE OF MYOBLAST CARDIAC TRANSPLANTATION – NEGATIVE REMODELING IS ASSOCIATED WITH LOCATION

PubMed Central

McCue, Jonathan D.; Swingen, Cory; Feldberg, Tanya; Caron, Gabe; Kolb, Adam; Denucci, Christopher; Prabhu, Somnath; Motilall, Randy; Breviu, Brian; Taylor, Doris A.

2009-01-01

Background Skeletal myoblast (SKMB) transplantation has been proposed as a therapy for ischemic cardiomyopathy due to its possible role in myogenesis. The relative safety and efficacy based on location within scar is not known. We hypothesized that SKMB transplanted into peripheral scar (compared to central scar) would more effectively attenuate negative left ventricular (LV) remodeling but at the risk of arrhythmia. Methods 34 New Zealand White rabbits underwent mid-left anterior descending artery (LAD) ligation to produce a transmural LV infarction. One month after LAD ligation SKMBs were injected either in the scar center (n=13) or scar periphery (n=10) and compared to saline injection (n=11). Holter monitoring and MRI was performed pre-injection; Holter monitoring was continued until two weeks post injection, with follow-up MRI at one month. Results Centrally-treated animals demonstrated increased LV end systolic volume, end diastolic volume and mass that correlated with injected cell number. There was a trend toward attenuation of negative LV remodeling in peripherally-treated animals compared to vehicle. Significant late ectopy was seen in several centrally-injected animals with no late ectopy seen in peripherally-injected animals. Conclusions We noted untoward effects with respect to negative LV remodeling following central injection, suggesting that transplanted cell location with respect to scar may be a key factor in the safety and efficacy of SKMB cardiac transplantation. Administration of SKMBs into peripheral scar appears safe with a trend toward improved function in comparison to sham injection. PMID:18187097

Intravascular ultrasound of the proximal left anterior descending artery is sufficient to detect early cardiac allograft vasculopathy.

PubMed

Floré, Vincent; Brown, Adam J; Pettit, Stephen J; West, Nick E J; Lewis, Clive; Parameshwar, Jayan; Hoole, Stephen P

2018-02-01

Cardiac allograft vasculopathy (CAV) can be detected early with intravascular ultrasound (IVUS), but there is limited information on the most efficient imaging protocol. Coronary angiography and IVUS of the three coronary arteries were performed. Volumetric IVUS analysis was performed, and a Stanford grade determined for each vessel. Eighteen patients were included 18 (range 12-24) months after transplantation. Angiographic CAV severity ranged from none (CAV0) to mild (CAV1), whereas IVUS CAV severity ranged from none (Stanford grade I) to severe (grade IV). Maximal intimal thickness measured with IVUS was significantly greater in the LAD (0.84 ± 0.48 mm) than in the LCX (0.46 ± 0.32 mm) or the RCA (0.53 ± 0.41 mm, P = .005). Diagnostic accuracy of IVUS in the left anterior descending artery was 100% (18 of 18 Stanford grades matched the patient's highest overall Stanford grade), 66% in the right coronary artery (12 of 18), and 56% in the left circumflex artery (11 of 18). The minimal required length of left anterior descending artery pullbacks to attain 100% accuracy was 36 mm (range 3-36 mm) distal from the guide catheter ostium. These data suggest that focal IVUS imaging of the proximal LAD followed by volumetric analysis may suffice when screening for transplant vasculopathy. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Intracoronary infusion of catecholamines causes focal arrhythmias in pigs.

PubMed

Doppalapudi, Harish; Jin, Qi; Dosdall, Derek J; Qin, Hao; Walcott, Gregory P; Killingsworth, Cheryl R; Smith, William M; Ideker, Raymond E; Huang, Jian

2008-09-01

Acute ischemia causes myriad changes including increased catecholamines. We tested the hypothesis that elevated catecholamines alone are arrhythmogenic. A 504 electrode sock was placed over both ventricles in six open-chest pigs. During control infusion of saline through a catheter in the left anterior descending coronary artery (LAD), no sustained arrhythmias occurred, and the refractory period estimated by the activation recovery interval (ARI) was 175 +/- 14 ms in the LAD bed below the catheter. After infusion of isoproterenol at 0.1 microg/kg/min through the catheter, the ARI in this bed was significantly reduced to 109 +/- 10 ms. A sharp gradient of refractoriness of 43 +/- 10 ms was at the border of the perfused bed. Sustained monomorphic ventricular tachycardia occurred after drug infusion in the perfused bed or near its boundary in all animals with a cycle length of 329 +/- 26 ms and a focal origin. The maximum slope of the ARI restitution curve at the focal origins of the tachyarrhythmias was always <1 (0.62 +/- 0.15). Similar results with a focal arrhythmia origin occurred in two additional pigs in which intramural mapping was performed with 36 plunge needle electrodes in the left ventricular perfused bed. Regional elevation of a catecholamine, which is one of the alterations produced by acute ischemia, can by itself cause tachyarrhythmias. These arrhythmias are closely associated with a shortened refractory period and a large gradient of the spatial distribution of refractoriness but not with a steep restitution curve.

Tests of a habitat suitability model for black-capped chickadees

USGS Publications Warehouse

Schroeder, Richard L.

1990-01-01

The black-capped chickadee (Parus atricapillus) Habitat Suitability Index (HSI) model provides a quantitative rating of the capability of a habitat to support breeding, based on measures related to food and nest site availability. The model assumption that tree canopy volume can be predicted from measures of tree height and canopy closure was tested using data from foliage volume studies conducted in the riparian cottonwood habitat along the South Platte River in Colorado. Least absolute deviations (LAD) regression showed that canopy cover and over story tree height yielded volume predictions significantly lower than volume estimated by more direct methods. Revisions to these model relations resulted in improved predictions of foliage volume. The relation between the HSI and estimates of black-capped chickadee population densities was examined using LAD regression for both the original model and the model with the foliage volume revisions. Residuals from these models were compared to residuals from both a zero slope model and an ideal model. The fit model for the original HSI differed significantly from the ideal model, whereas the fit model for the original HSI did not differ significantly from the ideal model. However, both the fit model for the original HSI and the fit model for the revised HSI did not differ significantly from a model with a zero slope. Although further testing of the revised model is needed, its use is recommended for more realistic estimates of tree canopy volume and habitat suitability.

[Two cases of acute coronary syndrome after intake of Clavis Panax].

PubMed

Atar, Aslı İnci; Er, Okan; Güven, Abdullah; Eryonucu, Beyhan

2012-04-01

Atherosclerotic cardiovascular disease is an epidemic in today's world. It is one of the most common causes of hospitalization and death. Therefore, remedies to control or heal the disease are continuously sought. In addition to scientifically researched therapies, patients frequently utilize alternative medicine. However, effective and toxic doses, metabolisms, and drug interactions of the herbs and herbal nutrition supplements are largely unknown. Herein, we present two cases with acute coronary syndrome. The first case was admitted with a diagnosis of acute inferior myocardial infaction (MI) and a stent was implanted to the occluded right coronary artery (RCA). There was a 50% stenosis in his left anterior descending artery (LAD). He was admitted with a diagnosis of non-ST elevation MI (NSTEMI) 6 months later. In the coronary angiogram, there was stent restenosis in RCA, the lesion in LAD had become thrombotic and progressed to a stenosis of 90%. He was referred to surgical revascularization. The second case was admitted for acute inferior MI and a stent was implanted to the occluded circumflex artery. Two months later, he was hospitalized for NSTEMI. Progression of coronary plaques to stenosis and stent restenosis was detected and he was referred to surgical revascularization. Both patients used the product sold as Clavis Panax, which contains panax ginseng, tribulus terrestris, and oat, after their first coronary intervention. Intake of a mixture of plant extracts may have serious consequences in humans as drug interactions and side effects are unknown.

The Response of the BATSE LADs to Radiation From the Crab Nebula and Plans for Radioactivity Studies on Space Station

NASA Technical Reports Server (NTRS)

Laird, C. E.

1996-01-01

The Burst And Transient Source Experiment (BATSE) onboard the Compton Gamma-Ray Observatory (CGRO) was designed to measure X-rays and gamma rays with energies from about 50 keV to above 2 MeV. As with many scientific investigations, the success of the original experiment lead to additional areas of research interest. In the case of BATSE the ability to observe the radiation from sources down to about 20 keV became readily apparent. This lead to a continuing program of measuring the spectrum of radiation from stellar objects at these lower energies. One of these, the Crab Nebula, has a very steady radiation flux and, thus, has become a "standard candle" for such measurements. The Large Area Detectors (LADS) on BATSE contain a 1.27-cm thick, 25.4-cm radius NaI(Tl) detector behind a 6.35-mm thick polystyrene Charged Particle Detector (CPD) used to "veto" charged particles signals. The detectors have been calibrated with a series of gamma and X-ray sources and the results carefully simulated with a Monte Carlo code. In the calibration process the computer simulation accounts for scattering from material in the counting room as well as the BATSE structure. For an orbiting detector, scattering from the entire spacecraft must be modeled as well as for all covering material over the detectors. Five years after CGRO was launched on April 5, 1991, a large body of observational data has been taken of the Crab Nebula. The technique used for these observations, and for many other X-ray sources, is Earth occultation. From the perspective of the spacecraft, the Earth occults most stellar objects once in orbit, i.e., the signal is lost as the source sets and is regained as the source rises. A careful analysis of the continuing signals from all sources measured allows for an accurate measurement of the spectrum of a given source. An analysis of this data from the Crab has indicated that the LADs are very responsive at energies as low as 20 keV-at energies below the range of calibration. While the model accounts for many of the interactions of the photons with the detectors, the observation of nonstatistical deviations at low energy and at small angles has suggested a need to recalibrate at energies where the attenuation effects are increasing exponentially.

On the Form of the Collective Bremsstrahlung Recoil Force in a Nonequilibrium Relativistic Beam-Plasma System.

DTIC Science & Technology

1984-01-01

RD-RI39 895 ON THE FORM OF THE COLLECTIVE BREMSSTRRHLUNG RECOIL i / i FORCE IN A NONEQUILIBRIUM RELATIVISTIC BEAM-PLASMA SYSTEM(U) HARRY DIAMOND LABS...A A O- I I .. . .:. .~ . ." . .- . . . AD Al 39895 H DL-TR-2026 .- 2 ,January 1984 ’ On the Form of the Collective Bremsstrahlung Recoil:O Kodf...Nonequillbrium Relativistic Beam-Plasma System; by Howard It. Brandt A and -t 4 C.. 4 :;x.. 4 4~ . Approw for *4444 𔃿 . U.S.~ Arm Lad Dee ,7 , .1 I . A L

Application of Near Infrared Spectroscopy, Intravascular Ultrasound and the Coronary Calcium Score to Predict Adverse Coronary Events

DTIC Science & Technology

2014-10-01

Kenneth&&Moore& 6/12/14 Smith RCA& stent ,&LAD&small&with&70%&lesion&poor&target,&Circ&too&tortuous Salvatore&Maccaron 12DJunD14 Smith Declined Edward...VanWingerden 9/10/14 Smith advanced&age,&no&targets&for&imaging&due&to&bypass&grafts&and&several& stents Van&McGlavan 10/1/14 Hopkins life&expectancy&less...than&3&years&&very&advanced&age Gene&Church 10/3/14 Marques no&IVUS&targets&due&to&bypass&grafts,& stents Ronald&Berry 10/3/14 Tabesh no&IVUS&targets&due

A History of the Los Angeles District, U.S. Army Corps of Engineers, 1898-1965

DTIC Science & Technology

1975-01-01

Pehrson, Robert J. Malley, H. McK. Roper, Jr. , and John V. Foley -in stressing the importance of the study. The Historical Program Committee, LAD...will be stressed in this historical study to demonstrate how the District met the challenge of the times. 17 Ever conscious of its dual civil and...58 A crane in the quarry near Riverside hoists a piece of "A" rock from a truck to a flatcar on the railroad. I n·ternational crises and

Transient left septal and anterior fascicular block associated with type 1 electrocardiographic Brugada pattern.

PubMed

Pérez-Riera, Andrés Ricardo; Barbosa-Barros, Raimundo; Penachini da Costa de Rezende Barbosa, Marianne; Daminello-Raimundo, Rodrigo; de Abreu, Luiz Carlos

The left septal fascicular block (LSFB) or blockage of the middle fibers of the left bundle branch is probably caused mainly by - in the developed world - the proximal obstruction of the left anterior descending artery (LAD) before its first anterior septal perforator branch (S 1 ). The association of transient LSFB and left anterior fascicular block (LAFB) - left bifascicular block - and the electrocardiographic type 1 Brugada pattern (BrP) has not been described in the literature yet. Copyright © 2017 Elsevier Inc. All rights reserved.

Color image processing and vision system for an automated laser paint-stripping system

NASA Astrophysics Data System (ADS)

Hickey, John M., III; Hise, Lawson

1994-10-01

Color image processing in machine vision systems has not gained general acceptance. Most machine vision systems use images that are shades of gray. The Laser Automated Decoating System (LADS) required a vision system which could discriminate between substrates of various colors and textures and paints ranging from semi-gloss grays to high gloss red, white and blue (Air Force Thunderbirds). The changing lighting levels produced by the pulsed CO2 laser mandated a vision system that did not require a constant color temperature lighting for reliable image analysis.

Air Power and Limited War: An Analysis of the Air Campaigns against North Vietnam as Instruments of National Policy

DTIC Science & Technology

1987-01-01

prepoftderantly negative policyr will ... retard the decision" in war.3 This observation also fits my detloltioft. i 2Carl von Clausewitz, On Wa trans ...var. but also the enemy’s xi to fight. In the United States. strategic bombing proponents 1Carl von Clausewitz, OnIWa trans . and ed. Michael Hovard and...Khruahchev. Khrushchov Rembers trans . and ed. Strobe Talbott (Boston: Little, Brown. and Company, 1970), pp. 367-372. 36 Ma•elkov. LAvrentil BriA, Lad

Removing the cells from adult bone marrow derived stem cell therapy does not eliminate cardioprotection.

PubMed

Yasin, Mohammed

2013-04-01

The debate as to whether adult stem cell therapy is regenerative or not continues. The non-regenerative benefits of adult bone marrow-derived stem cell therapy were investigated by testing whether the supernatant derived from unfractionated bone marrow mononuclear cells might be cardioprotective in an animal model of myocardial ischaemia-reperfusion injury. Regional myocardial reperfusion injury was acquired by 25 min reversible left anterior descending coronary artery (LAD) occlusion followed by 2 h reperfusion, in anaesthetized Wistar male rats. Unfractionated bone marrow mononuclear cells (BMMNC) isolated from sibling Wistar male rat whole bone marrow were phenotyped by fluorescence activated cell sorting flowcytometry for the haematopoietic stem cell surface markers c-kit, CD34, CD45 and CD133. Animals subjected to regional myocardial reperfusion injury received either 10 million BMMNC or BMMNC supernatant (BMS); both were collected in 0.5 ml phosphate-buffered saline and delivered by intravenous bolus at the onset of reperfusion. The left ventricular region distal to the LAD occlusion point was excised for measurement of myocardial infarct size and proteomic analysis, which was used to identify whether there were any differences in myocardial proteins associated with intravenous injection of either BMMNC or BMS. BMMNC were phenotyped to be c-kit(+) (7 ± 1%), CD34(+) (7 ± 1%), CD45(+) (54 ± 6%), CD133(+) (15 ± 1%). The supernatant reduced myocardial infarct size (BMS 34 ± 2%, n = 15 vs control 57 ± 2%, n = 7, P < 0.0001), which was comparable to the reduction in infarct size afforded by the injection of cells (BMMNC 33 ± 3% vs control 57 ± 2%, n = 10, P < 0.0001). Proteomics of hearts treated with either BMS or BMMNC demonstrated higher expression of (i) anti-apoptotic signal transduction protein: 14-3-3-epsilon (1.5-fold); (ii) anti-oxidants: peroxiredoxin-6 (2.1-fold); (iii) heat shock proteins: alpha B-crystallin (1.7-fold), heat shock protein 72 (2.8-fold), tumour necrosis factor receptor-1 associated protein (2.3-fold), ischaemia responsive protein-94 (1.6-fold); (iv) glycolytic protein: glyceraldehyde-3-phosphate dehydrogenase (2.3-fold); (v) mitochondrial respiratory proteins: mitochondrial aconitase (4.7-fold), voltage-dependent anion-selective channel protein-1 (VDAC-1) (2.7-fold). Regional myocardial reperfusion injury can be attenuated by intravenous administration of either BMMNC or BMS at the onset of reperfusion, which suggests adult stem cells mediate non-regenerative cardioprotection.

Electromechanical wave imaging and electromechanical wave velocity estimation in a large animal model of myocardial infarction.

PubMed

Costet, Alexandre; Melki, Lea; Sayseng, Vincent; Hamid, Nadira; Nakanishi, Koki; Wan, Elaine; Hahn, Rebecca; Homma, Shunichi; Konofagou, Elisa

2017-11-29

Echocardiography is often used in the clinic for detection and characterization of myocardial infarction. Electromechanical wave imaging (EWI) is a non-invasive ultrasound-based imaging technique based on time-domain incremental motion and strain estimation that can evaluate changes in contractility in the heart. In this study, electromechanical activation is assessed in infarcted heart to determine whether EWI is capable of detecting and monitoring infarct formation. Additionally, methods for estimating electromechanical wave (EW) velocity are presented, and changes in the EW propagation velocity after infarct formation are studied. Five (n  =  5) adult mongrels were used in this study. Successful infarct formation was achieved in three animals by ligation of the left anterior descending (LAD) coronary artery. Dogs were survived for a few days after LAD ligation and monitored daily with EWI. At the end of the survival period, dogs were sacrificed and TTC (tetrazolium chloride) staining confirmed the formation and location of the infarct. In all three dogs, as soon as day 1 EWI was capable of detecting late-activated and non-activated regions, which grew over the next few days. On final day images, the extent of these regions corresponded to the location of infarct as confirmed by staining. EW velocities in border zones of infarct were significantly lower post-infarct formation when compared to baseline, whereas velocities in healthy tissues were not. These results indicate that EWI and EW velocity might help with the detection of infarcts and their border zones, which may be useful for characterizing arrhythmogenic substrate.

IFATS Collection: Human Adipose Tissue-Derived Stem Cells Induce Angiogenesis and Nerve Sprouting Following Myocardial Infarction, in Conjunction with Potent Preservation of Cardiac Function

PubMed Central

Cai, Liying; Johnstone, Brian H.; Cook, Todd G.; Tan, Jian; Fishbein, Michael C.; Chen, Peng-Sheng; March, Keith L.

2010-01-01

The administration of therapeutic cell types, such as stem and progenitor cells, has gained much interest for the limitation or repair of tissue damage caused by a variety of insults. However, it is still uncertain whether the morphological and functional benefits are mediated predominantly via cell differentiation or paracrine mechanisms. Here, we assessed the extent and mechanisms of adipose-derived stromal/stem cells (ASC)-dependent tissue repair in the context of acute myocardial infarction. Human ASCs in saline or saline alone was injected into the peri-infarct region in athymic rats following left anterior descending (LAD) coronary artery ligation. Cardiac function and structure were evaluated by serial echocardiography and histology. ASC-treated rats consistently exhibited better cardiac function, by all measures, than control rats 1 month following LAD occlusion. Left ventricular (LV) ejection fraction and fractional shortening were improved in the ASC group, whereas LV remodeling and dilation were limited in the ASC group compared with the saline control group. Anterior wall thinning was also attenuated by ASC treatment, and post-mortem histological analysis demonstrated reduced fibrosis in ASC-treated hearts, as well as increased peri-infarct density of both arterioles and nerve sprouts. Human ASCs were persistent at 1 month in the peri-infarct region, but they were not observed to exhibit significant cardiomyocyte differentiation. Human ASCs preserve heart function and augment local angiogenesis and cardiac nerve sprouting following myocardial infarction predominantly by the provision of beneficial trophic factors. PMID:18772313

A novel leukocyte adhesion deficiency caused by expressed but nonfunctional β2 integrins Mac-1 and LFA-1

PubMed Central

Hogg, Nancy; Stewart, Mairi P.; Scarth, Sarah L.; Newton, Rebecca; Shaw, Jacqueline M.; Law, S.K. Alex; Klein, Nigel

1999-01-01

In the leukocyte adhesion deficiency (LAD)-1 syndrome, there is diminished expression of β2(CD18) integrins. This is caused by lesions in the β2-subunit gene and gives rise to recurrent bacterial infections, impaired pus formation, and poor wound healing. We describe a patient with clinical features compatible with a moderately severe phenotype of LAD-1 but who expresses the β2 integrins lymphocyte function– associated molecule (LFA)-1 and Mac-1 at 40%–60% of normal levels. This level of expression should be adequate for normal integrin function, but both the patient's Mac-1 on neutrophils and LFA-1 on T cells failed to bind ligands such as fibrinogen and intercellular adhesion molecule (ICAM)-1, respectively, or to display a β2-integrin activation epitope after adhesion-inducing stimuli. Unexpectedly, divalent cation treatment induced the patient's T cells to bind to ICAM-2 and ICAM-3. Sequencing of the patient's two CD18 alleles revealed the mutations S138P and G273R. Both mutations are in the β2-subunit conserved domain, with S138P a putative divalent cation coordinating residue in the metal ion–dependent adhesion site (MIDAS) motif. After K562 cell transfection with α subunits, the mutated S138P β subunit was coexpressed but did not support function, whereas the G273R mutant was not expressed. In summary, the patient described here exhibits failure of the β2 integrins to function despite adequate levels of cell-surface expression. PMID:9884339

Increase in coronary blood flow by intra-aortic balloon counterpulsation in a porcine model of myocardial reperfusion.

PubMed

Bonios, Michael J; Pierrakos, Charalampos N; Argiriou, Michael; Dalianis, Argirios; Terrovitis, John V; Dolou, Paraskevi; Drakos, Stavros G; Koudoumas, Dimitrios; Charitos, Christos E; Anastasiou-Nana, Maria I

2010-02-04

Studies of the IABP have reported variable effects on coronary blood flow (CBF). The purpose of the present study was to measure the changes in coronary blood flow induced by intra-aortic balloon pump (IABP) counterpulsation in normal and reperfused porcine myocardium. A 30-ml IABP was placed in the descending aorta of 6 open-chest pigs. Each pig underwent occlusion of the mid-left anterior descending (LAD) coronary artery for 1 h, followed by reperfusion for 2 h. The effects of IABP support on systolic aortic pressure (SAP) and aortic end-diastolic pressure were recorded. The mean CBF, distal to the LAD occlusion site was measured at baseline and during reperfusion, with and without IABP counterpulsation. The IABP decreased SAP and aortic end-diastolic pressure in normal and reperfused myocardium, and maintained a peak aortic diastolic augmentation at the level of SAP. In normal myocardium, the IABP decreased mean CBF by 8.4+/-2.2% (p<0.001). At 2, 15, 30, 60, 90 and 120 min of reperfusion, the IABP increased mean CBF by 11.5+/-6.8%, 8.0+/-7.0%, 11.2+/-6.9%, 12.4+/-12.9%, 23.5+/-9.9% and 8.9+/-6.9%, of the corresponding value without the assistance of the IABP (all p<0.05). In the normal heart, IABP counterpulsation decreased CBF, probably because of a decrease in myocardial oxygen demand from a decreased afterload. During reperfusion the IABP increased CBF, suggesting that it might effectively mitigate the no-reflow phenomenon. Copyright 2008 Elsevier Ireland Ltd. All rights reserved.

Analysis of serial coronary artery flow patterns early after primary angioplasty: new insights into the dynamics of the microcirculation.

PubMed

Sharif, Dawod; Rofe, Guy; Sharif-Rasslan, Amal; Goldhammer, Ehud; Makhoul, Nabeel; Shefer, Arie; Hassan, Amin; Rauchfleisch, Shmuel; Rosenschein, Uri

2008-06-01

The temporal behavior of the coronary microcirculation in acute myocardial infarction may affect outcome. Diastolic deceleration time and early systolic flow reversal derived from coronary artery blood flow velocity patterns reflect microcirculatory function. To assess left anterior descending coronary artery flow velocity patterns using Doppler transthoracic echocardiography after primary percutaneous coronary intervention, in patients with anterior AMI. Patterns of flow velocity patterns of the LAD were obtained using transthoracic echocardiography-Doppler in 31 consecutive patients who presented with anterior AMI. Measurements were done at 6 hours, 36-48 hours, and 5 days after successful PPCI. Measurements of DDT and pressure half times (Pt%), as well as observation for ESFR were performed. In the first 2 days following PPCI, the average DDT (600 +/- 340 msec) was shorter than on day 5 (807 +/- 332 msec) (P < 0.012), FVP in the first 2 days were dynamic and bidirectional: from short DDT (< 600 msec) to long DDT (> 600 msec) and vice versa. On day 5 most DDTs became longer. Pt1/2 at 6 hours was not different than at day 2 (174 +/- 96 vs. 193 +/- 99 msec, P = NS) and became longer on day 5 (235 +/- 98 msec, P = 0.012). Bidirectional patterns were also observed in the ESFR in 6 patients (19%) at baseline, in 4 (13%) at 36 hours, and in 2 (6.5%) on day 5 after PPCI. Flow velocity patterns of the LAD after PPCI in AMI are dynamic and reflect unpredictable changes in microcirculation.

Influence of minor deterioration of renal function after PCI on outcome in patients with ST-elevation myocardial infarction.

PubMed

Kanic, Vojko; Suran, David; Vollrath, Maja; Tapajner, Alojz; Kompara, Gregor

2017-10-01

Our aim was to assess the possible impact of a deterioration of renal function (DRF) not fulfilling the criteria for acute kidney injury after percutaneous coronary intervention (PCI) on outcome in patients with ST-elevation myocardial infarction (STEMI) on 30-day and long-term outcomes. Data is lacking on the influence of DRF after PCI on outcome in patients with STEMI. The present study is an analysis of 2572 STEMI patients who underwent PCI. The group with DRF (1022 patients) and the group without DRF (1550 patients) were compared. Thirty-day and long-term all-cause mortality were observed. Data was analyzed using descriptive statistics. Similar mortality was observed in both groups at day 30 (4.2% patients with DRF died vs 3.2% without DRF; ns) but more patients had died in the DRF group (18.9% patients with DRF vs 14.0% without DRF; P = 0.001) by the end of the observation period. After adjustments, DRF did not independently predict long-term mortality. Age more than 70 years, bleeding, hyperlipidemia, renal dysfunction on admission, anemia on admission, diabetes, PCI of LAD, the use of more than 200 mL contrast, but not DRF after PCI, were identified as independent prognostic factors for increased long-term mortality. Renal dysfunction, bleeding, contrast >200 mL, hyperlipidemia, age >70 years, anemia, and PCI LAD predicted DRF. DRF identified patients at increased risk of higher long-term mortality but was not independently associated with mortality. © 2017, Wiley Periodicals, Inc.

The impact of prompt gamma compensation on myocardial blood flow measurements with rubidium-82 dynamic PET.

PubMed

Armstrong, Ian S; Memmott, Matthew J; Tonge, Christine M; Arumugam, Parthiban

2018-04-01

Rubidium-82 myocardial perfusion imaging is a well-established technique for assessing myocardial ischemia. With continuing interest on myocardial blood flow (MBF) and myocardial flow reserve (MFR) measurements, there is a requirement to fully appreciate the impact of technical aspects of the process. One such factor for rubidium-82 is prompt gamma compensation (PGC). This study aims to assess the impact of PGC on MBF and MFR calculated from dynamic Rb-82 data. Dynamic rest and stress images were acquired on a Siemens Biograph mCT and reconstructed with and without PGC in 50 patients (29 male). MBF and MFR were measured in the three main coronary territories as well as globally. With PGC, statistically significant reductions in MBF were observed in LAD (-6.9%), LCx (-4.8%), and globally (-6.5%) but only in obese patients. Significant increases in MBF were observed in RCA (+6.4%) in only nonobese patients. In very obese patients, differences of up to 40% in MBF were observed between PGC and non-PGC images. In nearly all cases, similar PGC differences were observed at stress and rest so there were no significant differences in MFR; however, in a small number of very obese patients, differences in excess of 20% were observed. PGC results in statistically significant changes in MBF, with the greatest reductions observed in the LAD and LCx territories of obese patients. In most cases, the impact on stress and rest data is of similar relative magnitudes and changes to MFR are small.

The real estate of myoblast cardiac transplantation: negative remodeling is associated with location.

PubMed

McCue, Jonathan D; Swingen, Cory; Feldberg, Tanya; Caron, Gabe; Kolb, Adam; Denucci, Christopher; Prabhu, Somnath; Motilall, Randy; Breviu, Brian; Taylor, Doris A

2008-01-01

Skeletal myoblast transplantation has been proposed as a therapy for ischemic cardiomyopathy owing to its possible role in myogenesis. The relative safety and efficacy based on location within scar is not known. We hypothesized that skeletal myoblasts transplanted into peripheral scar (compared with central scar) would more effectively attenuate negative left ventricular (LV) remodeling but at the risk of arrhythmia. New Zealand White rabbits (n = 34) underwent mid-left anterior descending artery (LAD) ligation to produce a transmural LV infarction. One month after LAD ligation, skeletal myoblasts were injected either in the scar center (n = 13) or scar periphery (n = 10) and compared with saline injection (n = 11). Holter monitoring and magnetic resonance imaging (MRI) was performed pre-injection; Holter monitoring was continued until 2 weeks after injection, with follow-up MRI at 1 month. The centrally treated animals demonstrated increased LV end-systolic volume, end-diastolic volume, and mass that correlated with the number of injected cells. There was a trend toward attenuation of negative LV remodeling in peripherally treated animals compared with vehicle. Significant late ectopy was seen in several centrally injected animals, with no late ectopy seen in peripherally injected animals. We noted untoward effects with respect to negative LV remodeling after central injection, suggesting that transplanted cell location with respect to scar may be a key factor in the safety and efficacy of skeletal myoblast cardiac transplantation. Administration of skeletal myoblasts into peripheral scar appears safe, with a trend toward improved function in comparison with sham injection.

Preserved hyperaemic response in (distal) string sign left internal mammary artery grafts.

PubMed

Hartman, Joost; Kelder, Hans; Ackerstaff, Rob; van Swieten, Henry; Vermeulen, Freddy; Bogers, Ad

2007-02-01

To correlate supraclavicular ultrasonography at rest and in hyperaemic response with angiographically patent and (distal) 'string sign' left internal mammary artery (LIMA) to left anterior descending (LAD) area grafts. Fifty-three patients with LIMA to LAD area grafting were prospectively entered in a follow-up study. Arteriography (native and LIMA) was performed at 1.4+/-0.8 years postoperatively and ultrasonography was performed at rest, in hyperaemic response and 2min after hyperaemic response at 1.8+/-0.8 years postoperatively and was compared to arteriography. Ultrasonographic parameters analysed were systolic and diastolic peak velocity, systolic and diastolic velocity integral, diastolic/systolic peak velocity ratio and diastolic/total velocity integral ratio. One patient was excluded because obesity hampered ultrasonography. Arteriography demonstrated functional grafts in 43 patients (group I), sequential distal 'string sign grafts' in 4 patients (group II) and total 'string sign grafts' in 5 patients (group III). Between the groups all ultrasonographic velocities showed a significant linear relation (p

HMC-1 human mast cells synthesize neurotensin (NT) precursor, secrete bioactive NT-like peptide(s) and express NT receptor NTS1.

PubMed

Cochrane, David E; Carraway, Robert E; Harrington, Kimberly; Laudano, Melissa; Rawlings, Stephen; Feldberg, Ross S

2011-12-01

To determine if mast cells synthesize the inflammatory peptide, neurotensin (NT), secrete immunoreactive and bioactive NT, and express the NT receptor NTS1. HMC-1 cells, pleural mast cells from Sprague-Dawley rats, LAD2 mast cells, and human cord blood mast cells were used. HMC-1 cells were stimulated with NT, C48/80, mastoparan, or PGE(2). For changes in cutaneous vascular permeability, anesthetized rats were injected intravenously with Evans Blue dye and intradermally with saline, NT, histamine, diphenhydramine, and C48/80. RT-PCR was used to identify RNA transcripts. Histamine was measured by fluorometric assay. In vivo cutaneous vascular permeability assays, radio-immunoassays for NT, Western blotting for the NT precursor protein and NTS1 protein from HMC-1 cells and tissues from rats were used. Immunohistochemistry was used to identify NT precursor-like proteins in HMC-1 mast cells. HMC-1 cells express mRNAs for NT precursor, PC5A processing enzyme and NTS1 receptor. Human cord blood mast cells and LAD2 mast cells express mRNA transcripts for NT precursor and NTS1. Western blotting showed NT precursor and NTS1 receptor in HMC1. Rat tissues with high numbers of mast cells contained NT precursor proteins. NT-like peptides from HMC-1 displayed NT-like bioactivity. HMC-1 mast cells synthesize and secrete immunoreactive and bioactive NT-like peptide(s) and express the NT receptor, suggesting that NT from mast cells might serve autocrine and paracrine roles.

Electromechanical wave imaging and electromechanical wave velocity estimation in a large animal model of myocardial infarction

NASA Astrophysics Data System (ADS)

Costet, Alexandre; Melki, Lea; Sayseng, Vincent; Hamid, Nadira; Nakanishi, Koki; Wan, Elaine; Hahn, Rebecca; Homma, Shunichi; Konofagou, Elisa

2017-12-01

Echocardiography is often used in the clinic for detection and characterization of myocardial infarction. Electromechanical wave imaging (EWI) is a non-invasive ultrasound-based imaging technique based on time-domain incremental motion and strain estimation that can evaluate changes in contractility in the heart. In this study, electromechanical activation is assessed in infarcted heart to determine whether EWI is capable of detecting and monitoring infarct formation. Additionally, methods for estimating electromechanical wave (EW) velocity are presented, and changes in the EW propagation velocity after infarct formation are studied. Five (n  =  5) adult mongrels were used in this study. Successful infarct formation was achieved in three animals by ligation of the left anterior descending (LAD) coronary artery. Dogs were survived for a few days after LAD ligation and monitored daily with EWI. At the end of the survival period, dogs were sacrificed and TTC (tetrazolium chloride) staining confirmed the formation and location of the infarct. In all three dogs, as soon as day 1 EWI was capable of detecting late-activated and non-activated regions, which grew over the next few days. On final day images, the extent of these regions corresponded to the location of infarct as confirmed by staining. EW velocities in border zones of infarct were significantly lower post-infarct formation when compared to baseline, whereas velocities in healthy tissues were not. These results indicate that EWI and EW velocity might help with the detection of infarcts and their border zones, which may be useful for characterizing arrhythmogenic substrate.

Pseudomonas aeruginosa RsmA Plays an Important Role during Murine Infection by Influencing Colonization, Virulence, Persistence, and Pulmonary Inflammation▿

PubMed Central

Mulcahy, Heidi; O'Callaghan, Julie; O'Grady, Eoin P.; Maciá, María D.; Borrell, Nuria; Gómez, Cristina; Casey, Pat G.; Hill, Colin; Adams, Claire; Gahan, Cormac G. M.; Oliver, Antonio; O'Gara, Fergal

2008-01-01

The ability of Pseudomonas aeruginosa to cause a broad range of infections in humans is due, at least in part, to its adaptability and its capacity to regulate the expression of key virulence genes in response to specific environmental conditions. Multiple two-component response regulators have been shown to facilitate rapid responses to these environmental conditions, including the coordinated expression of specific virulence determinants. RsmA is a posttranscriptional regulatory protein which controls the expression of a number of virulence-related genes with relevance for acute and chronic infections. Many membrane-bound sensors, including RetS, LadS, and GacS, are responsible for the reciprocal regulation of genes associated with acute infection and chronic persistence. In P. aeruginosa this is due to sensors influencing the expression of the regulatory RNA RsmZ, with subsequent effects on the level of free RsmA. While interactions between an rsmA mutant and human airway epithelial cells have been examined in vitro, the role of RsmA during infection in vivo has not been determined yet. Here the function of RsmA in both acute and chronic models of infection was examined. The results demonstrate that RsmA is involved in initial colonization and dissemination in a mouse model of acute pneumonia. Furthermore, while loss of RsmA results in reduced colonization during the initial stages of acute infection, the data show that mutation of rsmA ultimately favors chronic persistence and results in increased inflammation in the lungs of infected mice. PMID:18025099

48 CFR 1852.217-72 - Phased acquisition using progressive competition down-selection procedures.

Code of Federal Regulations, 2011 CFR

2011-10-01

... to and including the date upon which Phase 2 proposals are requested. Any such changes in evaluation... procurement using a progressive competition down-selection technique between phases. In this technique, two or more contractors will be selected for Phase 1. It is expected that the single contractor for Phase 2...

Quantitative assessment on coronary computed tomography angiography (CCTA) image quality: comparisons between genders and different tube voltage settings.

PubMed

Chian, Teo Chee; Nassir, Norziana Mat; Ibrahim, Mohd Izuan; Yusof, Ahmad Khairuddin Md; Sabarudin, Akmal

2017-02-01

This study was carried out to quantify and compare the quantitative image quality of coronary computed tomography angiography (CCTA) between genders as well as between different tube voltages scan protocols. Fifty-five cases of CCTA were collected retrospectively and all images including reformatted axial images at systolic and diastolic phases as well as images with curved multi planar reformation (cMPR) were obtained. Quantitative image quality including signal intensity, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of right coronary artery (RCA), left anterior descending artery (LAD), left circumflex artery (LCx) and left main artery (LM) were quantified using Analyze 12.0 software. Six hundred and fifty-seven coronary arteries were evaluated. There were no significant differences in any quantitative image quality parameters between genders. 100 kilovoltage peak (kVp) scanning protocol produced images with significantly higher signal intensity compared to 120 kVp scanning protocol (P<0.001) in all coronary arteries in all types of images. Higher SNR was also observed in 100 kVp scan protocol in all coronary arteries except in LCx where 120 kVp showed better SNR than 100 kVp. There were no significant differences in image quality of CCTA between genders and different tube voltages. Lower tube voltage (100 kVp) scanning protocol is recommended in clinical practice to reduce the radiation dose to patient.

Comparison of left anterior descending coronary artery hemodynamics before and after angioplasty.

PubMed

Ramaswamy, S D; Vigmostad, S C; Wahle, A; Lai, Y G; Olszewski, M E; Braddy, K C; Brennan, T M H; Rossen, J D; Sonka, M; Chandran, K B

2006-02-01

Coronary artery disease (CAD) is characterized by the progression of atherosclerosis, a complex pathological process involving the initiation, deposition, development, and breakdown of the plaque. The blood flow mechanics in arteries play a critical role in the targeted locations and progression of atherosclerotic plaque. In coronary arteries with motion during the cardiac contraction and relaxation, the hemodynamic flow field is substantially different from the other arterial sites with predilection of atherosclerosis. In this study, our efforts focused on the effects of arterial motion and local geometry on the hemodynamics of a left anterior descending (LAD) coronary artery before and after clinical intervention to treat the disease. Three-dimensional (3D) arterial segments were reconstructed at 10 phases of the cardiac cycle for both pre- and postintervention based on the fusion of intravascular ultrasound (IVUS) and biplane angiographic images. An arbitrary Lagrangian-Eulerian formulation was used for the computational fluid dynamic analysis. The measured arterial translation was observed to be larger during systole after intervention and more out-of-plane motion was observed before intervention, indicating substantial alterations in the cardiac contraction after angioplasty. The time averaged axial wall shear stress ranged from -0.2 to 9.5 Pa before intervention compared to -0.02 to 3.53 Pa after intervention. Substantial oscillatory shear stress was present in the preintervention flow dynamics compared to that in the postintervention case.

Evaluation of balanced steady-state free precession (TrueFISP) and K-space segmented gradient echo sequences for 3D coronary MR angiography with navigator gating at 3 Tesla.

PubMed

Kaul, M G; Stork, A; Bansmann, P M; Nolte-Ernsting, C; Lund, G K; Weber, C; Adam, G

2004-11-01

To test the feasibility of k-space segmented gradient-echo pulse sequences for free-breathing coronary magnetic resonance angiography (cMRA) on a clinical 3T system. T2-prepared, fat-suppressed turbo field echo (TFE, turboFLASH, SFPGR) as well as balanced TFE (b-TFE, trueFISP, FIESTA, segmented SSFP) sequences with navigator gating for prospective motion correction were applied on a 3T system equipped with a six-element phased-array cardiac coil. In 15 healthy volunteers, the right coronary artery (RCA) was examined with TFE and b-TFE sequences. Due to examination time limitations, the left coronary artery (LM/LAD) was examined exclusively with the TFE sequence in ten volunteers. Image quality was graded on a five point scale (0 = not visualized to 4 = excellent). The length, diameter and sharpness of the vessels and the contrast-to-noise ratios (CNR) were measured. 98 % of all major segments (proximal/middle/distal) of the RCA could be seen with the TFE sequence and 82 % with the b-TFE sequence. The image quality for the three segments was graded higher for the TFE sequence (2.7/2.7/1.5) than for the b-TFE sequence (1.9/1.6/0.9) with P: (< or = 0.001/< or = 0.004/< or = 0.056). The kappa of the interobserver variability was 0.75 for the TFE sequence and 0.8 for the b-TFE sequence. The measured vessel lengths were longer for the TFE sequence (95 +/- 22 mm) than for the b-TFE sequence (80 +/- 40 mm; P < or = 0.115). No significant changes (P < or = 0.074, P < or = 0.145) in diameter and vessel sharpness of the RCAs were observed between the TFE (2.4 +/- 0.3 mm, 60 % +/- 5) and b-TFE sequences (2.4 +/- 0.3 mm, 62 % +/- 6). The CNR was higher for the TFE sequence (10.1 +/- 3.4) than for the b-TFE sequence (6.6 +/- 2.1; P < or = 0.014). All ten main and proximal segments of the LM/LAD, which were examined exclusively with the TFE sequence, were visible with grade 2.5 and 2.1. The middle segment was visible in seven cases with grade 1.3. In three cases, the distal segment was visible with grade 0.5. The vessel length was 78 +/- 27 mm and the CNR 11.9 +/- 2.4. The conventional TFE technique has demonstrated good feasibility for cMRA at 3T. In its operational availability at 3T, the b-TFE sequence is inferior to the TFE sequence.

Helium Purge Flow Prevention of Atmospheric Contamination of the Cryogenically Cooled Optics of Orbiting Infrared Telescopes: Calculation of He-O Differential Cross Section,

DTIC Science & Technology

1981-06-05

interactions. Aquilanti and coworkers were able to obtain two analytic forms for the interatomic potential --a Lennard - Jones (12, 6) and an exp(a, 6) function...Sec. UI.D 38 ences between the 3R and 3E- potential functions which described the interac- tions of ground-state oxygen and helium atoms. Instead, for...AO-AIOI 152 AEROSPACE CORP EL SEUMOO CA CHEMISTRY AND PHYSICS LAD r/6 17 HELIUM PLRE FLOW PREVENTION OF ATMOSPHERIC CONTAMINATION OF TAR fTCiO )JN81

DoD Electronic Data Interchange (EDI) Convention: ASC X12 Transaction Set 858 Freight Government Bill of Lading Shipment Information (Version 003010)

DTIC Science & Technology

1993-02-01

Segment: BX General Shipment Information Level: A Sequence: 30 Usage: M Max Use: 1 Loop: Purpose: To transmit identification numbers and other basic ...official code as- signed to a city or point (for ratemaking purposes) within a city. 930210 10.7.25 DEPARTM•B•T OF DOOM4N GOVERMET SILL OF LAD#M wDI...development group as the official code as- signed to a city or point (for ratemaking purposes) within a city. 930210 10.7.27 DEPARTMENT OF DG:dEI GOVWERJT

Vibrationally Excited Ions: Quenching Reaction Enhancement, Lifetimes

DTIC Science & Technology

1991-01-01

affinities in our lad- A,.=Af exp( - AS/IR) = I .IX 10𔄃 cm’ S_ with limits der . Any change it. P.A.(Br), ither due to a change in bet~een 7.Sx l3 9and...8217K P Huber and G Hereberg. C oeto of Drateooc Molecules ( Van "M Tubs’, G JasAay. N D Toeddy. and B. B. Fergusn. Ini J Mass Nostrand-Reinhold. New York...objectives and it seemed possible .aat neut - rals such as N,. Xe and CF, might provide suitable monitor gases for vibra- tionally excited HBr*. For HBr

Direct phase selection of initial phases from single-wavelength anomalous dispersion (SAD) for the improvement of electron density and ab initio structure determination.

PubMed

Chen, Chung-De; Huang, Yen-Chieh; Chiang, Hsin-Lin; Hsieh, Yin-Cheng; Guan, Hong-Hsiang; Chuankhayan, Phimonphan; Chen, Chun-Jung

2014-09-01

Optimization of the initial phasing has been a decisive factor in the success of the subsequent electron-density modification, model building and structure determination of biological macromolecules using the single-wavelength anomalous dispersion (SAD) method. Two possible phase solutions (φ1 and φ2) generated from two symmetric phase triangles in the Harker construction for the SAD method cause the well known phase ambiguity. A novel direct phase-selection method utilizing the θ(DS) list as a criterion to select optimized phases φ(am) from φ1 or φ2 of a subset of reflections with a high percentage of correct phases to replace the corresponding initial SAD phases φ(SAD) has been developed. Based on this work, reflections with an angle θ(DS) in the range 35-145° are selected for an optimized improvement, where θ(DS) is the angle between the initial phase φ(SAD) and a preliminary density-modification (DM) phase φ(DM)(NHL). The results show that utilizing the additional direct phase-selection step prior to simple solvent flattening without phase combination using existing DM programs, such as RESOLVE or DM from CCP4, significantly improves the final phases in terms of increased correlation coefficients of electron-density maps and diminished mean phase errors. With the improved phases and density maps from the direct phase-selection method, the completeness of residues of protein molecules built with main chains and side chains is enhanced for efficient structure determination.

Usefulness of Single Photon Emission Computed Tomography/Computed Tomography Fusion-Hybrid Imaging to Evaluate Coronary Artery Disorders in Patients with a History of Kawasaki Disease.

PubMed

Abe, Masanori; Fukazawa, Ryuji; Ogawa, Shunichi; Watanabe, Makoto; Fukushima, Yoshimitsu; Kiriyama, Tomonari; Hayashi, Hiromitsu; Itoh, Yasuhiko

2016-01-01

The coronary arterial lesions of Kawasaki disease are mainly dilative lesions, aneurysms, and stenotic lesions formed before, after, and between aneurysms; these lesions develop in multiple branches resulting in complex coronary hemodynamics. Diagnosis of myocardial ischemia and infarction and evaluation of the culprit coronary arteries and regions is critical to evaluating the treatment and prognosis of patients. This study used hybrid imaging, in which multidetector computed tomographic (CT) images for coronary CT angiography (CCTA) and stress myocardial perfusion single-photon emission CT (SPECT) images were fused. We investigated the diagnosis of blood vessels and regions responsible for myocardial ischemia and infarction in patients with complex coronary arterial lesions; in addition, we evaluated myocardial lesions that developed directly under giant coronary artery aneurysms. The subjects were 17 patients with Kawasaki disease with multiple coronary arterial lesions (median age, 18.0 years; 16 male). Both CCTA using 64-row CT and adenosine-loading myocardial SPECT were performed. Three branches, the right coronary artery (RCA), left anterior descending branch (LAD), and left circumflex branch, were evaluated with the conventional side-by-side interpretation, in which the images were lined up for diagnosis, and hybrid imaging, in which the CCTA and SPECT images were fused with computer processing. In addition, the myocardial lesions directly under giant coronary artery aneurysms were investigated with fusion imaging. Images sufficient for evaluation were acquired in all 17 patients. In the RCA, coronary arterial lesions were detected with CCTA in 16 patients. The evaluations were consistent between the side-by-side and fusion interpretation in 14 patients, and the blood vessel responsible for the myocardial ischemic region was identified in 2 patients. In the left circumflex branch, coronary arterial lesions were confirmed with 3-dimensional CT in 5 patients, and the the culprit coronary arteries for myocardial ischemia/infarction were confirmed with the fusion interpretation but not with the side-by-side interpretation. In the LAD, coronary arterial lesions were present in all patients, and the diagnosis was made with the fusion interpretation in 10 patients. In the LAD, small-range infarct lesions were detected directly under the giant coronary artery aneurysm in 8 patients, but were not confirmed with the side-by-side interpretation. Fusion imaging was capable of accurately evaluating myocardial ischemia/infarction as cardiovascular sequelae of Kawasaki disease and confirming the culprit coronary arteries. In addition, analysis of fusion images confirmed that small-range infarct lesions were concomitantly present directly under giant coronary artery aneurysms in the anterior descending coronary artery.

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

Mittauer, Kathryn E.; Deraniyagala, Rohan; Li, Jonathan G.

Purpose: Recent knowledge on the effects of cardiac toxicity warrants greater precision for left-sided breast radiotherapy. Different breath-hold (BH) maneuvers (abdominal vs thoracic breathing) can lead to chest wall positional variations, even though the patient’s tidal volume remains consistent. This study aims to investigate the feasibility of using optical tracking for real-time quality control of active breathing coordinator (ABC)-assisted deep inspiration BH (DIBH). Methods: An in-house optical tracking system (OTS) was used to monitor ABC-assisted DIBH. The stability and localization accuracy of the OTS were assessed with a ball-bearing phantom. Seven patients with left-sided breast cancer were included. A free-breathingmore » (FB) computed tomography (CT) scan and an ABC-assisted BH CT scan were acquired for each patient. The OTS tracked an infrared (IR) marker affixed over the patient’s xiphoid process to measure the positional variation of each individual BH. Using the BH within which the CT scan was performed as the reference, the authors quantified intra- and interfraction BH variations for each patient. To estimate the dosimetric impact of BH variations, the authors studied the positional correlation between the marker and the left breast using the FB CT and BH CT scans. The positional variations of 860 BHs as measured by the OTS were retrospectively incorporated into the original treatment plans to evaluate their dosimetric impact on breast and cardiac organs [heart and left anterior descending (LAD) artery]. Results: The stability and localization accuracy of the OTS was within 0.2 mm along each direction. The mean intrafraction variation among treatment BHs was less than 2.8 mm in all directions. Up to 12.6 mm anteroposterior undershoot, where the patient’s chest wall displacement of a BH is less than that of a reference BH, was observed with averages of 4.4, 3.6, and 0.1 mm in the anteroposterior, craniocaudal, and mediolateral directions, respectively. A high positional correlation between the marker and the breast was found in the anteroposterior and craniocaudal directions with respective Pearson correlation values of 0.95 and 0.93, but no mediolateral correlation was found. Dosimetric impact of BH variations on breast coverage was negligible. However, the mean heart dose, mean LAD dose, and max LAD dose were estimated to increase from 1.4/7.4/18.6 Gy (planned) to 2.1/15.7/31.0 Gy (delivered), respectively. Conclusions: In ABC-assisted DIBH, large positional variation can occur in some patients, due to their different BH maneuvers. The authors’ study has shown that OTS can be a valuable tool for real-time quality control of ABC-assisted DIBH.« less

48 CFR 570.305 - Two-phase design-build selection procedures.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Two-phase design-build...-phase design-build selection procedures. (a) These procedures apply to acquisitions of leasehold interests if the contracting officer uses the two-phase design-build selection procedures authorized by 570...

48 CFR 570.305 - Two-phase design-build selection procedures.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Two-phase design-build...-phase design-build selection procedures. (a) These procedures apply to acquisitions of leasehold interests if the contracting officer uses the two-phase design-build selection procedures authorized by 570...

48 CFR 570.305 - Two-phase design-build selection procedures.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Two-phase design-build...-phase design-build selection procedures. (a) These procedures apply to acquisitions of leasehold interests if the contracting officer uses the two-phase design-build selection procedures authorized by 570...

48 CFR 570.305 - Two-phase design-build selection procedures.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Two-phase design-build...-phase design-build selection procedures. (a) These procedures apply to acquisitions of leasehold interests if the contracting officer uses the two-phase design-build selection procedures authorized by 570...

Aldehydic load and aldehyde dehydrogenase 2 profile during the progression of post-myocardial infarction cardiomyopathy: benefits of Alda-1

PubMed Central

Gomes, Katia M.S.; Bechara, Luiz R.G.; Lima, Vanessa M.; Ribeiro, Márcio A.C.; Campos, Juliane C.; Dourado, Paulo M.; Kowaltowski, Alicia J.; Mochly-Rosen, Daria; Ferreira, Julio C.B.

2015-01-01

Background/Objectives We previously demonstrated that reducing cardiac aldehydic load by aldehyde dehydrogenase 2 (ALDH2), a mitochondrial enzyme responsible for metabolizing the major lipid peroxidation product, protects against acute ischemia/reperfusion injury and chronic heart failure. However, time-dependent changes in ALDH2 profile, aldehydic load and mitochondrial bioenergetics during progression of post-myocardial infarction (post-MI) cardiomyopathy is unknown and should be established to determine the optimal time window for drug treatment. Methods Here we characterized cardiac ALDH2 activity and expression, lipid peroxidation, 4-hydroxy-2-nonenal (4-HNE) adduct formation, glutathione pool and mitochondrial energy metabolism and H2O2 release during the 4 weeks after permanent left anterior descending (LAD) coronary artery occlusion in rats. Results We observed a sustained disruption of cardiac mitochondrial function during the progression of post-MI cardiomyopathy, characterized by >50% reduced mitochondrial respiratory control ratios and up to 2 fold increase in H2O2 release. Mitochondrial dysfunction was accompanied by accumulation of cardiac and circulating lipid peroxides and 4-HNE protein adducts and down-regulation of electron transport chain complexes I and V. Moreover, increased aldehydic load was associated with a 90% reduction in cardiac ALDH2 activity and increased glutathione pool. Further supporting an ALDH2 mechanism, sustained Alda-1 treatment (starting 24hrs after permanent LAD occlusion surgery) prevented aldehydic overload, mitochondrial dysfunction and improved ventricular function in post-MI cardiomyopathy rats. Conclusion Taken together, our findings demonstrate a disrupted mitochondrial metabolism along with an insufficient cardiac ALDH2-mediated aldehyde clearance during the progression of ventricular dysfunction, suggesting a potential therapeutic value of ALDH2 activators during the progression of post-myocardial infarction cardiomyopathy. PMID:25464432

Effects of incisor extraction on jaw and tongue motor representations within face sensorimotor cortex of adult rats.

PubMed

Avivi-Arber, Limor; Lee, Jye-Chang; Sessle, Barry J

2010-04-01

Loss of teeth is associated with changes in somatosensory inputs and altered patterns of mastication, but it is unclear whether tooth loss is associated with changes in motor representations within face sensorimotor cortex of rats. We used intracortical microstimulation (ICMS) and recordings of cortically evoked muscle electromyographic (EMG) activities to test whether changes occur in the ICMS-defined motor representations of the left and right jaw muscles [masseter, anterior digastric (LAD, RAD)] and tongue muscle [genioglossus (GG)] within the cytoarchitectonically defined face primary motor cortex (face-M1) and adjacent face primary somatosensory cortex (face-S1) 1 week following extraction of the right mandibular incisor in anesthetized (ketamine-HCl) adult male Sprague-Dawley rats. Under local and general anesthesia, an "extraction" group (n = 8) received mucoalveolar bone surgery and extraction of the mandibular right incisor. A "sham-extraction" group (n = 6) received surgery with no extraction. A "naive" group (n = 6) had neither surgery nor extraction. Data were compared by using mixed-model repeated-measures ANOVA. Dental extraction was associated with a significantly increased number of sites within face-M1 and face-S1 from which ICMS evoked RAD EMG activities, a lateral shift of the RAD and LAD centers of gravity within face-M1, shorter onset latencies of ICMS-evoked GG activities within face-M1 and face-S1, and an increased number of sites within face-M1 from which ICMS simultaneously evoked RAD and GG activities. Our novel findings suggest that dental extraction may be associated with significant neuroplastic changes within the rat's face-M1 and adjacent face-S1 that may be related to the animal's ability to adapt to the altered oral state. (c) 2009 Wiley-Liss, Inc.

Profound bioenergetic abnormalities in peri-infarct myocardial regions.

PubMed

Hu, Qingsong; Wang, Xiaohong; Lee, Joseph; Mansoor, Abdul; Liu, Jingbo; Zeng, Lepeng; Swingen, Cory; Zhang, Ge; Feygin, Julia; Ochiai, Koichi; Bransford, Toni L; From, Arthur H L; Bache, Robert J; Zhang, Jianyi

2006-08-01

Regions of myocardial infarct (MI) are surrounded by a border zone (BZ) of normally perfused but dysfunctional myocardium. Although systolic dysfunction has been attributed to elevated wall stress in this region, there is evidence that intrinsic abnormalities of contractile performance exist in BZ myocardium. This study examined whether decreases of high-energy phosphates (HEP) and mitochondrial F(1)F(0)-ATPase (mtATPase) subunits typical of failing myocardium exist in BZ myocardium of compensated postinfarct remodeled hearts. Eight pigs were studied 6 wk after MI was produced by ligation of the left anterior descending coronary artery (LAD) distal to the second diagonal. Animals developed compensated LV remodeling with a decrease of ejection fraction from 54.6 +/- 5.4% to 31 +/- 2.1% (MRI) 5 wk after LAD occlusion. The remote zone (RZ) myocardium demonstrated modest decreases of ATP and mtATPase components. In contrast, BZ myocardium demonstrated profound abnormalities with ATP levels decreased to 42% of normal, and phosphocreatine-to-ATP ratio ((31)P-magnetic resonance spectroscopy) decreased from 2.06 +/- 0.19 in normal hearts to 1.07 +/- 0.10, with decreases in alpha-, beta-, OSCP, and IF(1) subunits of mtATPase, especially in the subendocardium. The reduction of myocardial creatine kinase isoform protein expression was also more severe in the BZ relative to the RZ myocardium. These abnormalities were independent of a change in mitochondrial content because the mitochondrial citrate synthase protein level was not different between the BZ and RZ. This regional heterogeneity of ATP content and expression of key enzymes in ATP production suggests that energetic insufficiency in the peri-infarct region may contribute to the transition from compensated LV remodeling to congestive heart failure.

Prevalence of Atherosclerotic Coronary Stenosis in Asymptomatic North Indian Population: A Post-mortem Coronary Angiography Study.

PubMed

Bansal, Yogender Singh; Mandal, Shatrugan Prasad; Kumar, Senthil; Setia, Puneet

2015-09-01

A preliminary study of coronaries using post-mortem angiography was undertaken to see the prevalence of atherosclerotic coronary stenosis in non-cardiac unnatural deaths. This study was conducted in a tertiary care centre located in Chandigarh. A total of 128 medico-legal cases were studied comprising 88 males and 40 females. Post-mortem examinations of these MLC cases were conducted in the Department of Forensic Medicine, PGIMER, Chandigarh. All hearts were visually screened by post-mortem coronary angiography first and then grossly examined using serial transverse incision technique in positive screening cases to find the degree of narrowing. Of the study group, 34% males and 20% females showed evidence of narrowing on angiography. Of the males showing coronary stenosis, 83% had single vessel disease and 13% had double vessel disease, while only one individual had triple vessel disease. In cases of female, all the cases of coronary stenosis were single vessel disease. Left anterior descending coronary artery (LAD) was the most common vessel involved, followed by right coronary artery (RCA) & Left circumflex artery (LCX) and in cases of double vessel disease, LAD in combination with LCX was responsible for 75% of the cases. Remarkably 23.6% of study population in the age group of less than 40 years showed appreciable narrowing in at least one of the coronaries. In general, the prevalence of CAD is on the rise, particularly in younger population owing to the changes in their lifestyle and food habits. This preliminary study revealed evidence of narrowing of at least one coronary in 34% male and 20% female population and 23.6% subjects were less than 40 years old. Further detailed studies are needed especially in younger age group and to support the need for preventive cardiology in the early years of life.

Nicorandil improves myocardial function by regulating plasma nitric oxide and endothelin-1 in coronary slow flow

PubMed Central

Chen, Xiuhua; Li, Shan; Huo, Xuezhen; Fu, Xiuxiu; Dong, Xiaonan

2015-01-01

Background Coronary slow flow (CSF) is a special coronary microvascular disorder. The pathogenesis and effective therapeutics of CSF remain unclear. This study aimed to evaluate the global and regional functions of the left ventricle (LV) and investigate the efficacy of nicorandil in patients with CSF. Patients and methods Thirty-six patients with CSF in the left anterior descending (LAD) branch and 20 patients with normal coronary arteries were included. Global and regional functions of the LV supplied by LAD were measured using conventional Doppler echocardiography and two-dimensional speckle tracking echocardiography, respectively, within 24 h after coronary angiography. Concentrations of plasma nitric oxide (NO) and endothelin-1 (ET-1) were detected using colorimetry and radioimmunoassay, respectively. The function of the LV and the levels of NO and ET-1 were also investigated before and 90 days after treatment with 15 mg/day of nicorandil. Results Compared with the control group, the early diastolic peak velocity (E), E/A ratio, and plasma NO levels were lower, whereas the late diastolic peak flow velocity (A) and plasma ET-1 levels were significantly higher in the CSF group (P<0.05). The longitudinal strain rate peak of the LV was reduced significantly in CSF patients (P<0.001). After treatment, 75% (27/36) of CSF patients were free of chest pain. The values of E peak, E/A ratio, longitudinal strain rate peak, and plasma NO level were increased (P<0.001), whereas the ET-1 level was decreased in CSF patients (P<0.001). Conclusion Nicorandil may improve chest pain symptoms and the impaired function of the LV, possibly by increasing plasma NO and reducing ET-1 in CSF. PMID:25325437

The influence of roadside solid and vegetation barriers on near-road air quality

NASA Astrophysics Data System (ADS)

Ghasemian, Masoud; Amini, Seyedmorteza; Princevac, Marko

2017-12-01

The current study evaluates the influence of roadside solid and vegetation barriers on the near-road air quality. Reynolds Averaged Navier-Stokes (RANS) technique coupled with the k - ε realizable turbulence model is utilized to investigate the flow pattern and pollutant concentration. A scalar transport equation is solved for a tracer gas to represent the roadway pollutant emissions. In addition, a broad range of turbulent Schmidt numbers are tested to calibrate the scalar transport equation. Three main scenarios including flat terrain, solid barrier, and vegetative barrier are studied. To validate numerical methodology, predicted pollutant concentration is compared with published wind tunnel data. Results show that the solid barrier induces an updraft motion and lofts the vehicle emission plume. Therefore, the ground-level pollutant concentration decreases compared to the flat terrain. For the vegetation barrier, different sub-scenarios with different vegetation densities ranging from approximately flat terrain to nearly solid barrier are examined. Dense canopies act in a similar manner as a solid barrier and mitigate the pollutant concentration through vertical mixing. On the other hand, the high porosity vegetation barriers reduce the wind speed and lead to a higher pollutant concentration. As the vegetation density increases, i.e. the barrier porosity decreases, the recirculation zone behind the canopy becomes larger and moves toward the canopy. The dense plant canopy with LAD = 3.33m-2m3 can improve the near-road air quality by 10% and high porosity canopy with LAD = 1m-2m3 deteriorates near-road air quality by 15%. The results of this study can be implemented as green infrastructure design strategies by urban planners and forestry organizations.

Ventricular Tachycardia and Resembling Acute Coronary Syndrome During Pheochromocytoma Crisis

PubMed Central

Li, Shi-jun; Wang, Tao; Wang, Lin; Pang, Zhan-qi; Ma, Ben; Li, Ya-wen; Yang, Jian; Dong, He

2016-01-01

Abstract Pheochromocytomas are neuroendocrine tumors, and its cardiac involvement may include transient myocardial dysfunction, acute coronary syndrome (ACS), and even ventricular arrhythmias. A patient was referred for evaluation of stuttering chest pain, and his electrocardiogram showed T-wave inversion over leads V1 to V4. Coronary angiography showed 90% stenosis in the mid-left anterior descending coronary artery (LAD), which was stented. Five days later, the patient had ventricular tachycardia, and severe hypertension, remarkable blood pressure fluctuation between 224/76 and 70/50 mm Hg. The patient felt abdominal pain and his abdominal ultrasound showed suspicious right adrenal gland tumor. Enhanced computed tomography of adrenal gland conformed that there was a tumor in right adrenal gland accompanied by an upset level of aldosterone. The tumor was removed by laparoscope, and the pathological examination showed pheochromocytoma. After the surgery, the blood pressure turned normal gradually. There was no T-wave inversion in lead V1-V4. Our case illustrates a rare pheochromocytoma presentation with a VT and resembling ACS. In our case, the serious stenosis in the mid of LAD could be explained by worsen the clinical course of myocardial ischemia or severe coronary vasospasm by the excessive amounts of catecholamines released from the tumor. Coronary vasospasm was possible because he had no classic coronary risk factors (e.g. family history and smoking habit, essential hypertension, hyperglycemia and abnormal serum lipoprotein, high body mass index). Thus, pheochromocytoma was missed until he revealed the association of his symptoms with abdominalgia. As phaeochromocytomas that present with cardiovascular complications can be fatal, it is necessary to screen for the disease when patients present with symptoms indicating catecholamine excess. PMID:27057898

Dose reduction assessment in dynamic CT myocardial perfusion imaging in a porcine balloon-induced-ischemia model

NASA Astrophysics Data System (ADS)

Fahmi, Rachid; Eck, Brendan L.; Vembar, Mani; Bezerra, Hiram G.; Wilson, David L.

2014-03-01

We investigated the use of an advanced hybrid iterative reconstruction (IR) technique (iDose4, Philips Health- care) for low dose dynamic myocardial CT perfusion (CTP) imaging. A porcine model was created to mimic coronary stenosis through partial occlusion of the left anterior descending (LAD) artery with a balloon catheter. The severity of LAD occlusion was adjusted with FFR measurements. Dynamic CT images were acquired at end-systole (45% R-R) using a multi-detector CT (MDCT) scanner. Various corrections were applied to the acquired scans to reduce motion and imaging artifacts. Absolute myocardial blood flow (MBF) was computed with a deconvolution-based approach using singular value decomposition (SVD). We compared a high and a low dose radiation protocol corresponding to two different tube-voltage/tube-current combinations (80kV p/100mAs and 120kV p/150mAs). The corresponding radiation doses for these protocols are 7.8mSv and 34.3mSV , respectively. The images were reconstructed using conventional FBP and three noise-reduction strengths of the IR method, iDose. Flow contrast-to-noise ratio, CNRf, as obtained from MBF maps, was used to quantitatively evaluate the effect of reconstruction on contrast between normal and ischemic myocardial tissue. Preliminary results showed that the use of iDose to reconstruct low dose images provide better or comparable CNRf to that of high dose images reconstructed with FBP, suggesting significant dose savings. CNRf was improved with the three used levels of iDose compared to FBP for both protocols. When using the entire 4D dynamic sequence for MBF computation, a 77% dose reduction was achieved, while considering only half the scans (i.e., every other heart cycle) allowed even further dose reduction while maintaining relatively higher CNRf.

First validation of myocardial flow reserve assessed by dynamic 99mTc-sestamibi CZT-SPECT camera: head to head comparison with 15O-water PET and fractional flow reserve in patients with suspected coronary artery disease. The WATERDAY study.

PubMed

Agostini, Denis; Roule, Vincent; Nganoa, Catherine; Roth, Nathaniel; Baavour, Raphael; Parienti, Jean-Jacques; Beygui, Farzin; Manrique, Alain

2018-07-01

We assessed the feasibility of myocardial blood flow (MBF) and flow reserve (MFR) estimation using dynamic SPECT with a novel CZT camera in patients with stable CAD, in comparison with 15 O-water PET and fractional flow reserve (FFR). Thirty patients were prospectively included and underwent FFR measurements in the main coronary arteries (LAD, LCx, RCA). A stenosis ≥50% was considered obstructive and a FFR abnormal if ≤0.8. All patients underwent a dynamic rest/stress 99m Tc-sestamibi CZT-SPECT and 15 O-water PET for MBF and MFR calculation. Net retention kinetic modeling was applied to SPECT data to estimate global uptake values, and MBF was derived using Leppo correction. Ischemia by PET and CZT-SPECT was considered present if MFR was lower than 2 and 2.1, respectively. CZT-SPECT yielded higher stress and rest MBF compared to PET for global and LAD and LCx territories, but not in RCA territory. MFR was similar in global and each vessel territory for both modalities. The sensitivity, specificity, accuracy, positive and negative predictive value of CZT-SPECT were, respectively, 83.3, 95.8, 93.3, 100 and 85.7% for the detection of ischemia and 58.3, 84.6, 81.1, 36.8 and 93% for the detection of hemodynamically significant stenosis (FFR ≤ 0.8). Dynamic 99m Tc-sestamibi CZT-SPECT was technically feasible and provided similar MFR compared to 15 O-water PET and high diagnostic value for detecting impaired MFR and abnormal FFR in patients with stable CAD.

Comprehensive Assessment of Coronary Artery Disease by Using First-Pass Analysis Dynamic CT Perfusion: Validation in a Swine Model.

PubMed

Hubbard, Logan; Lipinski, Jerry; Ziemer, Benjamin; Malkasian, Shant; Sadeghi, Bahman; Javan, Hanna; Groves, Elliott M; Dertli, Brian; Molloi, Sabee

2018-01-01

Purpose To retrospectively validate a first-pass analysis (FPA) technique that combines computed tomographic (CT) angiography and dynamic CT perfusion measurement into one low-dose examination. Materials and Methods The study was approved by the animal care committee. The FPA technique was retrospectively validated in six swine (mean weight, 37.3 kg ± 7.5 [standard deviation]) between April 2015 and October 2016. Four to five intermediate-severity stenoses were generated in the left anterior descending artery (LAD), and 20 contrast material-enhanced volume scans were acquired per stenosis. All volume scans were used for maximum slope model (MSM) perfusion measurement, but only two volume scans were used for FPA perfusion measurement. Perfusion measurements in the LAD, left circumflex artery (LCx), right coronary artery, and all three coronary arteries combined were compared with microsphere perfusion measurements by using regression, root-mean-square error, root-mean-square deviation, Lin concordance correlation, and diagnostic outcomes analysis. The CT dose index and size-specific dose estimate per two-volume FPA perfusion measurement were also determined. Results FPA and MSM perfusion measurements (P FPA and P MSM ) in all three coronary arteries combined were related to reference standard microsphere perfusion measurements (P MICRO ), as follows: P FPA_COMBINED = 1.02 P MICRO_COMBINED + 0.11 (r = 0.96) and P MSM_COMBINED = 0.28 P MICRO_COMBINED + 0.23 (r = 0.89). The CT dose index and size-specific dose estimate per two-volume FPA perfusion measurement were 10.8 and 17.8 mGy, respectively. Conclusion The FPA technique was retrospectively validated in a swine model and has the potential to be used for accurate, low-dose vessel-specific morphologic and physiologic assessment of coronary artery disease. © RSNA, 2017.

Acute myocardial infarction in very young adults: A clinical presentation, risk factors, hospital outcome index, and their angiographic characteristics in North India-AMIYA Study.

PubMed

Sinha, Santosh Kumar; Krishna, Vinay; Thakur, Ramesh; Kumar, Ashutosh; Mishra, Vikas; Jha, Mukesh Jitendra; Singh, Karandeep; Sachan, Mohit; Sinha, Rupesh; Asif, Mohammad; Afdaali, Nasar; Mohan Varma, Chandra

2017-03-01

India is currently in the fourth stage of epidemiological transitions where cardiovascular disease is the leading cause of mortality and morbidity. Purpose of the present study was to assess the risk factors, clinical presentation, angiographic profile including severity, and in-hospital outcome of very young adults (aged ≤ 30 years) with first acute myocardial infarction (AMI). Total of 1,116 consecutive patients with ST-segment elevation acute myocardial infarction (STEMI) were studied between March 2013 and February 2015 at LPS Institute of Cardiology, Kanpur, Uttar Pradesh, India. Mean age of the patients was 26.3 years. Risk factors were smoking (78.5%), family history of premature coronary artery disease (CAD) (46.8%), obesity (39.1%), physical inactivity (38.7%) and stressful life events (29.6%). The most common symptom and presentation was chest pain and anterior wall myocardial infarction (AWMI) in 94.8% and 58.8%, respectively. About 80.6% of patients had obstructive CAD with single vessel disease (57.6%), double-vessel disease (12.9%) and left main involvement (3.2%). Left anterior descending (LAD) was commonest culprit artery (58.1%) followed by right coronary artery in 28.2%. In-hospital mortality was 2.8%. Percutaneous coronary intervention was performed in 71.6% of patients. Median number and length of stent were 1.18 and 28 ± 16 mm, respectively. AMI in very young adult occurred most commonly in male. Smoking was the most common risk factor. AWMI owing to LAD artery involvement was the most common presentation. Mean time of presentation after symptom onset was 16.9 hours. In contrast to western population, it is characterised by earlier onset, delayed presentation, more severity, diffuse disease, and more morbidity but with favourable in-hospital mortality.

Scalar Dispersion from Point Sources in a Realistic Urban Environment

NASA Astrophysics Data System (ADS)

Salesky, S.; Giometto, M. G.; Christen, A.; Parlange, M. B.

2016-12-01

Accurate modeling of scalar dispersion within and above urban canopies is critical to properly predict air quality and dispersion (e.g. accidental contaminant release) in urban environments. We perform large eddy simulations (LES) of scalar dispersion from point sources in a typical North American neighborhood using topography and foliage density derived from airborne LIDAR scans with 1 m resolution in Vancouver, BC, Canada. The added drag force due to trees is parameterized in the LES as a function of the leaf area density (LAD) profile. Conversely, drag from buildings is accounted for using a direct forcing approach immersed-boundary method. The scalar advection-diffusion equation is discretized in a finite-volume framework, and accurate mass conservation is enforced through a recently developed Cartesian cut cell method. Simulations are performed with trees for different values of LAD, representative of summer and winter conditions, as well as a case without trees. The effects of varying mean wind direction (derived from observed wind climatologies) on dispersion patterns are also considered. Scalar release locations in the LES are informed by spatially distributed measurements of carbon dioxide concentration; CO2 is used as a tracer for fossil fuel emissions, since source strengths are well-known and the contribution from biological processes in this setting is small (<10%). The effects of leaf area density, source height, and wind direction on scalar statistics including the growth of the mean concentration plume and the fraction that escapes the urban canopy layer will be considered. In a companion study, the presence of trees was found to strongly modify sweep and ejection patterns for the momentum flux; here we consider the related issue of how vegetation influences coherent structures responsible for scalar transport.

Hemodynamic analysis of sequential graft from right coronary system to left coronary system.

PubMed

Wang, Wenxin; Mao, Boyan; Wang, Haoran; Geng, Xueying; Zhao, Xi; Zhang, Huixia; Xie, Jinsheng; Zhao, Zhou; Lian, Bo; Liu, Youjun

2016-12-28

Sequential and single grafting are two surgical procedures of coronary artery bypass grafting. However, it remains unclear if the sequential graft can be used between the right and left coronary artery system. The purpose of this paper is to clarify the possibility of right coronary artery system anastomosis to left coronary system. A patient-specific 3D model was first reconstructed based on coronary computed tomography angiography (CCTA) images. Two different grafts, the normal multi-graft (Model 1) and the novel multi-graft (Model 2), were then implemented on this patient-specific model using virtual surgery techniques. In Model 1, the single graft was anastomosed to right coronary artery (RCA) and the sequential graft was adopted to anastomose left anterior descending (LAD) and left circumflex artery (LCX). While in Model 2, the single graft was anastomosed to LAD and the sequential graft was adopted to anastomose RCA and LCX. A zero-dimensional/three-dimensional (0D/3D) coupling method was used to realize the multi-scale simulation of both the pre-operative and two post-operative models. Flow rates in the coronary artery and grafts were obtained. The hemodynamic parameters were also showed, including wall shear stress (WSS) and oscillatory shear index (OSI). The area of low WSS and OSI in Model 1 was much less than that in Model 2. Model 1 shows optimistic hemodynamic modifications which may enhance the long-term patency of grafts. The anterior segments of sequential graft have better long-term patency than the posterior segments. With rational spatial position of the heart vessels, the last anastomosis of sequential graft should be connected to the main branch.

ICESat-2 bathymetry: an empirical feasibility assessment using MABEL

NASA Astrophysics Data System (ADS)

Forfinski, Nick; Parrish, Christopher

2016-10-01

The feasibility of deriving bathymetry from data acquired with ATLAS, the photon-counting lidar on NASA's upcoming ICESat-2 satellite, is assessed empirically by examining data from NASA's airborne ICESat-2 simulator, MABEL. The primary objectives of ICESat-2 will be to measure ice-sheet elevations, sea-ice thickness, and global biomass. However, the 6-beam, green-wavelength photon-counting lidar, combined with the 91-day repeat period and near-polar orbit, may provide unique opportunities to measure coastal bathymetry in remote, poorly-mapped areas of the globe. The study focuses on high-probability bottom returns in Keweenaw Bay, Lake Superior, acquired during the "Transit to KPMD" MABEL mission in August, 2012 at an AGL altitude of 20,000 m. Water-surface and bottom returns were identified and manually classified using MABEL Viewer, an in-house prototype data-explorer web application. Water-surface returns were observed in 12 green channels, and bottom returns were observed in 10 channels. Comparing each channel's mean water-surface elevation to a regional NOAA Nowcast water-level estimate revealed channel-specific elevation biases that were corrected for in our bathymetry estimation procedure. Additionally, a first-order refraction correction was applied to each bottom return. Agreement between the refraction-corrected depth profile and NOAA data acquired two years earlier by Fugro LADS with the LADS Mk II airborne system indicates that MABEL reliably detected bathymetry in depths up to 8 m, with an RMS difference of 0.7 m. In addition to feeding coastal bathymetry models, MABEL (and potentially ICESat-2 ATLAS) has the potential to seed algorithms for bathymetry retrieval from passive, multispectral satellite imagery by providing reference depths.

Induction of steatohepatitis (NASH) with insulin resistance in wildtype B6 mice by a western-type diet containing soybean oil and cholesterol.

PubMed

Henkel, Janin; Coleman, Charles Dominic; Schraplau, Anne; Jӧhrens, Korinna; Weber, Daniela; Castro, José Pedro; Hugo, Martin; Schulz, Tim Julius; Krämer, Stephanie; Schürmann, Annette; Püschel, Gerhard Paul

2017-03-21

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are hepatic manifestations of the metabolic syndrome. Many currently used animal models of NAFLD/NASH lack clinical features of either NASH or metabolic syndrome such as hepatic inflammation and fibrosis (e.g. high-fat diets) or overweight and insulin resistance (e.g. methionine-choline-deficient diets) or they are based on monogenetic defects (e.g. ob/ob mice). In the current study, a western-type diet containing soybean oil with high n 6-PUFA and 0.75% cholesterol (SOD+Cho) induced steatosis, inflammation and fibrosis accompanied by hepatic lipid peroxidation and oxidative stress in livers of C57BL/6-mice which in addition showed increased weight gain and insulin resistance, thus displaying a phenotype closely resembling all clinical features of NASH in patients with metabolic syndrome. In striking contrast a soybean oil-containing western-type diet without cholesterol (SOD) induced only mild steatosis but neither hepatic inflammation nor fibrosis, weight gain or insulin resistance. Another high-fat diet mainly consisting of lard and supplemented with fructose in drinking water (LAD+Fru) resulted in more prominent weight gain, insulin resistance and hepatic steatosis than SOD+Cho but livers were devoid of inflammation and fibrosis. Although both LAD+Fru- and SOD+Cho-fed animals had high plasma cholesterol, liver cholesterol was elevated only in SOD+Cho animals. Cholesterol induced expression of chemotactic and inflammatory cytokines in cultured Kupffer cells and rendered hepatocytes more susceptible to apoptosis. Summarizing, dietary cholesterol in SOD+Cho diet may trigger hepatic inflammation and fibrosis. SOD+Cho-fed animals may be a useful disease model displaying many clinical features of patients with the metabolic syndrome and NASH.

Distribution and Determinants of Myocardial Perfusion Grade Following Late Mechanical Recanalization of Occluded Infarct-Related Arteries Postmyocardial Infarction: A Report From the Occluded Artery Trial

PubMed Central

Jorapur, Vinod; Steigen, Terje K.; Buller, Christopher E.; Dẑavík, Vladimír; Webb, John G.; Strauss, Bradley H.; Yeoh, Eunice E.S.; Kurray, Peter; Sokalski, Leszek; Machado, Mauricio C.; Kronsberg, Shari S.; Lamas, Gervasio A.; Hochman, Judith S.; John Mancini, G.B.

2010-01-01

Objective To evaluate the distribution and determinants of myocardial perfusion grade (MPG) following late recanalization of persistently occluded infarct-related arteries (IRA). Background MPG reflects microvascular integrity. It is an independent prognostic factor following myocardial infarction, but has been studied mainly in the setting of early reperfusion. The occluded artery trial (OAT) enrolled stable patients with persistently occluded IRAs beyond 24 hr and up to 28 days post-MI. Methods Myocardial blush was assessed using TIMI MPG grading in 261 patients with TIMI 3 epicardial flow following IRA PCI. Patients demonstrating impaired (0–1) versus preserved (2–3) MPG were compared with regard to baseline clinical and pre-PCI angiographic characteristics. Results Impaired MPG was observed in 60 of 261 patients (23%). By univariate analysis, impaired MPG was associated with failed fibrinolytic therapy, higher heart rate, lower systolic blood pressure, lower ejection fraction, LAD occlusion, absence of collaterals (P < 0.01) and ST elevation MI, lower diastolic blood pressure, and higher systolic sphericity index (P < 0.05). By multivariable analysis, higher heart rate, LAD occlusion, absence of collaterals and higher systolic sphericity index (P < 0.01), and lower systolic blood pressure (P < 0.05) were independently associated with impaired MPG. Conclusion Preserved microvascular integrity was present in a high proportion of patients following late recanalization of occluded IRAs post-MI. Presence of collaterals was independently associated with preserved MPG and likely accounted for the high frequency of preserved myocardial perfusion in this clinical setting. Impaired MPG was associated with baseline clinical and angiographic features consistent with larger infarct size. PMID:18798327

Characterization of four CD18 mutants in leucocyte adhesion deficient (LAD) patients with differential capacities to support expression and function of the CD11/CD18 integrins LFA-1, Mac-1 and p150,95

PubMed Central

Shaw, J M; Al-Shamkhani, A; Boxer, L A; Buckley, C D; Dodds, A W; Klein, N; Nolan, S M; Roberts, I; Roos, D; Scarth, S L; Simmons, D L; Tan, S M; Law, S K A

2001-01-01

Leucocyte adhesion deficiency (LAD) is a hereditary disorder caused by mutations in the CD18 (β2 integrin) gene. Four missense mutations have been identified in three patients. CD18(A270V) supports, at a diminished level, CD11b/CD18 (Mac-1, αMβ2 integrin) and CD11c/CD18 (p150,95, αXβ2 integrin) expression and function but not CD11a/CD18 (LFA-1, αLβ2 integrin) expression. Conversely, CD18(A341P) supports a limited level of expression and function of CD11a/CD18, but not of the other two CD11/CD18 antigens. CD18(C590R) and CD18(R593C) show a decreasing capacity to associate with the CD11a, CD11c and CD11b subunits. Transfectants expressing the CD11a/CD18 with the C590R and R593C mutations are more adhesive than transfectants expressing wild-type LFA-1, and express the reporter epitope of the monoclonal antibody 24 constitutively. Thus, the four mutations affect CD18 differently in its capacities to support CD11/CD18 expression and adhesion. These results not only provide a biochemical account for the clinical diversity of patients with leucocyte adhesion deficiency, but also offer novel insights into the structural basis of interaction between the α and β subunits, which is an integral component in our understanding of integrin-mediated adhesion and its regulation. PMID:11703376

Electrotonic remodeling following myocardial infarction in dogs susceptible and resistant to sudden cardiac death.

PubMed

Del Rio, Carlos L; McConnell, Patrick I; Kukielka, Monica; Dzwonczyk, Roger; Clymer, Bradley D; Howie, Michael B; Billman, George E

2008-02-01

Passive electrical remodeling following myocardial infarction (MI) is well established. These changes can alter electrotonic loading and trigger the remodeling of repolarization currents, a potential mechanism for ventricular fibrillation (VF). However, little is known about the role of passive electrical markers as tools to identify VF susceptibility post-MI. This study investigated electrotonic remodeling in the post-MI ventricle, as measured by myocardial electrical impedance (MEI), in animals prone to and resistant to VF. MI was induced in dogs by a two-stage left anterior descending (LAD) coronary artery ligation. Before infarction, MEI electrodes were placed in remote (left circumflex, LCX) and infarcted (LAD) myocardium. MEI was measured in awake animals 1, 2, 7, and 21 days post-MI. Subsequently, VF susceptibility was tested by a 2-min LCX occlusion during exercise; 12 animals developed VF (susceptible, S) and 12 did not (resistant, R). The healing infarct had lower MEI than the normal myocardium. This difference was stable by day 2 post-MI (287 +/- 32 Omega vs. 425 +/- 62 Omega, P < 0.05). Significant differences were observed between resistant and susceptible animals 7 days post-MI; susceptible dogs had a wider electrotonic gradient between remote and infarcted myocardium (R: 89 +/- 60 Omega vs. S: 180 +/- 37 Omega). This difference increased over time in susceptible animals (252 +/- 53 Omega at 21 days) due to post-MI impedance changes on the remote myocardium. These data suggest that early electrotonic changes post-MI could be used to assess later arrhythmia susceptibility. In addition, passive-electrical changes could be a mechanism driving active-electrical remodeling post-MI, thereby facilitating the induction of arrhythmias.

TU-G-204-03: Dynamic CT Myocardial Perfusion Measurement Using First Pass Analysis and Maximum Slope Models

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

Hubbard, L; Ziemer, B; Sadeghi, B

Purpose: To evaluate the accuracy of dynamic CT myocardial perfusion measurement using first pass analysis (FPA) and maximum slope models. Methods: A swine animal model was prepared by percutaneous advancement of an angioplasty balloon into the proximal left anterior descending (LAD) coronary artery to induce varying degrees of stenosis. Maximal hyperaemia was achieved in the LAD with an intracoronary adenosine drip (240 µg/min). Serial microsphere and contrast (370 mg/mL iodine, 30 mL, 5mL/s) injections were made over a range of induced stenoses, and dynamic imaging was performed using a 320-row CT scanner at 100 kVp and 200 mA. The FPAmore » CT perfusion technique was used to make vessel-specific myocardial perfusion measurements. CT perfusion measurements using the FPA and maximum slope models were validated using colored microspheres as the reference gold standard. Results: Perfusion measurements using the FPA technique (P-FPA) showed good correlation with minimal offset when compared to perfusion measurements using microspheres (P- Micro) as the reference standard (P -FPA = 0.96 P-Micro + 0.05, R{sup 2} = 0.97, RMSE = 0.19 mL/min/g). In contrast, the maximum slope model technique (P-MS) was shown to underestimate perfusion when compared to microsphere perfusion measurements (P-MS = 0.42 P -Micro −0.48, R{sup 2} = 0.94, RMSE = 3.3 mL/min/g). Conclusion: The results indicate the potential for significant improvements in accuracy of dynamic CT myocardial perfusion measurement using the first pass analysis technique as compared with the standard maximum slope model.« less

Left ventricular systolic and diastolic function improve after acute myocardial infarction treated with acute percutaneous coronary intervention, but are not influenced by intracoronary injection of autologous mononuclear bone marrow cells: a 3 year serial echocardiographic sub-study of the randomized-controlled ASTAMI study.

PubMed

Beitnes, Jan Otto; Gjesdal, Ola; Lunde, Ketil; Solheim, Svein; Edvardsen, Thor; Arnesen, Harald; Forfang, Kolbjørn; Aakhus, Svend

2011-02-01

To clarify long-term changes in global, regional, and diastolic left ventricular (LV) function after intracoronary injection of autologous mononuclear bone marrow cells (mBMCs) in acute myocardial infarction (AMI). In the Autologous Stem cell Transplantation in Acute Myocardial Infarction (ASTAMI) study, 100 patients with anterior ST-elevation myocardial infarction and percutaneous coronary intervention on the left anterior descending artery (LAD) were randomized to receive intracoronary injection of mBMCs or not. Transthoracic echocardiography was performed at baseline, 3, 6, 12 months, and 3 years. Regional LV function was assessed by two-dimensional speckle-tracking echocardiography. From baseline to 3 years, LV ejection fraction changed from 45.7 to 47.5% in the mBMC group, and from 46.9 to 46.8% in the control group (P = 0.87 for difference in change over time between groups). Longitudinal strain in the LAD territory improved from -9.7 to -12.2% in the mBMC group and from -9.9 to -12.8% in the control group (P = 0.45). E/e' decreased from 14.7 to 12.9 in the mBMC group and from 14.8 to 11.9 in the control group (P = 0.31). There were no significant differences between groups in change of LV volumes, global systolic function, regional function, or diastolic function during 3 years follow-up. No differences between groups indicating beneficial effect of intracoronary mBMC injection could be identified. Both groups in ASTAMI experienced improvement of global, regional, and diastolic LV function after 3-6 months, with effects sustained at 3 years.

Post-infarct treatment with [Pyr1]apelin-13 exerts anti-remodelling and anti-apoptotic effects in rats' hearts.

PubMed

Azizi, Yaser; Imani, Alireza; Fanaei, Hamed; Khamse, Safoura; Parvizi, Mohammad Reza; Faghihi, Mahdieh

2017-01-01

Ischaemic heart disease is the main cause of mortality in the world. After myocardial infarction (MI) cardiomyocytes apoptosis and ventricular remodelling have occurred. Apelin is a peptide that has been shown to exert cardioprotective effects. The aim of this study was to investigate the anti-apoptotic and anti-remodelling effects of [Pyr¹]apelin-13 in the rat model of post-MI. Thirty-six male Wistar rats were randomly divided into three groups: (1) sham, (2) MI, and (3) MI treated with [Pyr¹] apelin-13 (MI+Apel). MI animals were subjected to 30-min ligation of the left anterior descending coronary artery (LAD) and 14 days of reperfusion. Twenty-four hours after LAD ligation, [Pyr¹]apelin-13 (10 nmol/kg/day, i.p.) was administered for five consecutive days. Hypertrophic parameters, left ventricular (LV) remodelling, and gene expression of Apel, apelin receptor (Apelr), Bax, caspase-3 (Casp-3), and Bcl-2 by real-time polymerase chain reaction and cardiomyocytes apoptosis by TUNEL immunostaining were assessed on day 14 post-MI. Post-infarct treatment with [Pyr¹]apelin-13 improved myocardial hypertrophic and LV remodelling parameters and led to a significant increase in the expression of Apel, Apelr, and Bcl-2, and a decrease in the expression of Bax and Casp-3. Furthermore, treatment with [Pyr¹]apelin-13 decreased cardiomyocyte apoptosis. [Pyr¹]apelin-13 has anti-hypertrophic, anti-remodelling, and anti-apoptotic effects via overexpression of Apel, Apelr, and Bcl-2 and reduces gene expression of Bax and Casp-3 in the infarcted myocardium, which can in turn lead to repair myocardium.

Spectroscopic micro-tomography of metallic-organic composites by means of photon-counting detectors

NASA Astrophysics Data System (ADS)

Pichotka, M.; Jakubek, J.; Vavrik, D.

2015-12-01

The presumed capabilities of photon counting detectors have aroused major expectations in several fields of research. In the field of nuclear imaging ample benefits over standard detectors are to be expected from photon counting devices. First of all a very high contrast, as has by now been verified in numerous experiments. The spectroscopic capabilities of photon counting detectors further allow material decomposition in computed tomography and therefore inherently adequate beam hardening correction. For these reasons measurement setups featuring standard X-ray tubes combined with photon counting detectors constitute a possible replacement of the much more cost intensive tomographic setups at synchrotron light-sources. The actual application of photon counting detectors in radiographic setups in recent years has been impeded by a number of practical issues, above all by restrictions in the detectors size. Currently two tomographic setups in Czech Republic feature photon counting large-area detectors (LAD) fabricated in Prague. The employed large area hybrid pixel-detector assemblies [1] consisting of 10×10/10×5 Timepix devices have a surface area of 143×143 mm2 / 143×71,5 mm2 respectively, suitable for micro-tomographic applications. In the near future LAD devices featuring the Medipix3 readout chip as well as heavy sensors (CdTe, GaAs) will become available. Data analysis is obtained by a number of in house software tools including iterative multi-energy volume reconstruction.In this paper tomographic analysis of of metallic-organic composites is employed to illustrate the capabilities of our technology. Other than successful material decomposition by spectroscopic tomography we present a method to suppress metal artefacts under certain conditions.

Progressively heterogeneous mismatch of regional oxygen delivery to consumption during graded coronary stenosis in pig left ventricle.

PubMed

Alders, David J C; Groeneveld, A B Johan; Binsl, Thomas W; van Beek, Johannes H G M

2015-11-15

In normal hearts, myocardial perfusion is fairly well matched to regional metabolic demand, although both are distributed heterogeneously. Nonuniform regional metabolic vulnerability during coronary stenosis would help to explain nonuniform necrosis during myocardial infarction. In the present study, we investigated whether metabolism-perfusion correlation diminishes during coronary stenosis, indicating increasing mismatch of regional oxygen supply to demand. Thirty anesthetized male pigs were studied: controls without coronary stenosis (n = 11); group I, left anterior descending (LAD) coronary stenosis leading to coronary perfusion pressure reduction to 70 mmHg (n = 6); group II, stenosis with perfusion pressure of about 35 mmHg (n = 6); and group III, stenosis with perfusion pressure of 45 mmHg combined with adenosine infusion (n = 7). [2-(13)C]- and [1,2-(13)C]acetate infusion was used to calculate regional O2 consumption from glutamate NMR spectra measured for multiple tissue samples of about 100 mg dry mass in the LAD region. Blood flow was measured with microspheres in the same regions. In control hearts without stenosis, regional oxygen extraction did not correlate with basal blood flow. Average myocardial O2 delivery and consumption decreased during coronary stenosis, but vasodilation with adenosine counteracted this. Regional oxygen extraction was on average decreased during stenosis, suggesting adaptation of metabolism to lower oxygen supply after half an hour of ischemia. Whereas regional O2 delivery correlated with O2 consumption in controls, this relation was progressively lost with graded coronary hypotension but partially reestablished by adenosine infusion. Therefore, coronary stenosis leads to heterogeneous metabolic stress indicated by decreasing regional O2 supply to demand matching in myocardium during partial coronary obstruction. Copyright © 2015 the American Physiological Society.

Measurement of cardiac dimensions with two-dimensional echocardiography in the living horse.

PubMed

Voros, K; Holmes, J R; Gibbs, C

1991-11-01

Two-dimensional echocardiography (2DE) was performed on 22 unsedated Thoroughbred and part Thoroughbred horses weighing between 411 and 650 kg to establish normal reference values for 2DE measurements. Animals stood during examinations performed with a 3.5 MHz mechanical sector transducer using various transducer positions and tomographic planes. Right ventricular diameter (RVD), ventricular septal thickness (VSTh), aortic diameter (AoD), area of the chordal lumen of the left ventricle (CTA), left ventricular diameter (LVD) and left atrial diameter (LAD) were determined at ventricular end-diastole (Ed) and/or end-systole (Es). Fractional shortening (FS) of the left ventricle and end-systolic left atrial to aortic ratio (LAD-Es:AoD-Es) also were calculated. Echocardiographic data were related to body weight by linear regression analysis. Intra-observer variability was checked in five horses by measuring each parameter during each of 10 consecutive cardiac cycles. The 2DE data were compared with M-mode values in published reports. In the 18 horses whose weight did not exceed 551 kg, repeatable recordings of good quality were obtained, and 2DE measurements could be made using intra-cardiac reference points. Increasing body weight proved to impose substantial limitations on measurements taken with the available machine and transducer. This problem might be overcome by using probes of lower frequency or equipment with higher quality image display at greater depth. The following parameters correlated significantly to body weight: VSTh-Es (r = 0.69; P less than 0.01). AoD-Es (r = 0.64; P less than 0.01) and CTA-Es (r = 0.84; P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Assessment of stenosis severity: Correlation of angiography, T1-201 scintigraphy, and intracoronary pressure gradients

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

Bateman, T.; Raymond, M.; Czer, L.

1984-01-01

To clarify the relationship between angiographic and hemodynamic stenosis severity and the appearance during stress-redistribution myocardial T1-201 scintigraphy (Ex-T1) of a visual (V) or quantitative (Q) perfusion defect (PD) or washout (WO) abnormality, 24 pts with CAD underwent intracoronary pressure gradient study at bypass surgery (CABG). All had pre-CABG Ex-T1 without interval deterioration. The mean diastolic pressure gradient (MDG) measured at reproducible hyperemic flow rates was determined for 34 stenoses (13 LAD, 7 LCX, 14 RCA) and compared with the results of Ex-T1 in subtended myocardial regions (LAD=anterior; LCX=posterolateral; RCA=inferior). Fourteen stenoses (50-99% diameter narrowing) were unassociated with VPD despitemore » maximal exercise: MDG was 9 +- 5mmHg, with MDG/mean aortic diastolic pressure (ADP) ratio of 0.12 +- 0.07. QPD and QWO analysis detected 8 of these. Thirteen stenoses (90-100% severity) led to reversible VPD: MDG was 36 +- 11 mm Hg, MDG/ADP ratio was 0.52 +- 0.17, and Q analysis was abnormal in 12/13. Seven stenoses (90-100% severity) subtended infarcted myocardium: MDG was 42 +- 21 mm Hg, MDG/ADP ratio was 0.52 +- 0.18, and V and Q analyses were abnormal in all. From this study, the authors derive the following conclusion: 1) Ex-T1 correlates better with hemodynamic severity of stenoses than does angiography; 2) V abnormalities identify stenoses of major angiographic and hemodynamic severity, while Q analysis detects some (57% in this study) stenoses of lesser severity; and 3) stenoses causing reversible Ex-T1 abnormalities present similar hemodynamic impediments to those causing myocardial infarcts.« less

Cadmium Alternatives for High-Strength Steel JTP. Phase 2

DTIC Science & Technology

2007-01-24

Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 U.S. AIR FORCE Project Overview Objective Assess DoD- selected cadmium alternatives in...focused) – Phase III (fatigue testing focused) • Down- selection of candidates for further testing after each phase of testing is complete (Phases I...Laboratories – Mr. John Marshall U.S. AIR FORCE Phase I Overview and Selection Process – Traditional plating (primary coatings): • Sputtered Aluminum

Measuring health literacy in individuals with diabetes: a systematic review and evaluation of available measures.

PubMed

Al Sayah, Fatima; Williams, Beverly; Johnson, Jeffrey A

2013-02-01

To identify instruments used to measure health literacy and numeracy in people with diabetes; evaluate their use, measurement scope, and properties; discuss their strengths and weaknesses; and propose the most useful, reliable, and applicable measure for use in research and practice settings. A systematic literature review was conducted to identify the instruments. Nutbeam's domains of health literacy and a diabetes health literacy skill set were used to evaluate the measurement scope of the identified instruments and to evaluate their applicability in people with diabetes. Fifty-six studies were included, from which one diabetes-specific (LAD) and eight generic measures of health literacy (REALM, REALM-R, TOFHLA, s-TOFHLA, NVS, 3-brief SQ, 3-level HL Scale, SILS) and one diabetes-specific (DNT) and two generic measures of numeracy (SNS, WRAT) were identified. These instruments were categorized into direct measures, that is, instruments that assess the performance of individuals on health literacy skills and indirect measures that rely on self-report of these skills. The most commonly used instruments measure selective domains of health literacy, focus mainly on reading and writing skills, and do not address other important skills such as verbal communication, health care system navigation, health-related decision making, and numeracy. The structure, mode, and length of administration and measurement properties were found to affect the applicability of these instruments in clinical and research settings. Indirect self- or clinician-administered measures are the most useful in both clinical and research settings. This review provides an evaluation of available health literacy measures and guidance to practitioners and researchers for selecting the appropriate measures for use in clinical settings and research applications.

Identification of atypical flight patterns

NASA Technical Reports Server (NTRS)

Statler, Irving C. (Inventor); Ferryman, Thomas A. (Inventor); Amidan, Brett G. (Inventor); Whitney, Paul D. (Inventor); White, Amanda M. (Inventor); Willse, Alan R. (Inventor); Cooley, Scott K. (Inventor); Jay, Joseph Griffith (Inventor); Lawrence, Robert E. (Inventor); Mosbrucker, Chris (Inventor)

2005-01-01

Method and system for analyzing aircraft data, including multiple selected flight parameters for a selected phase of a selected flight, and for determining when the selected phase of the selected flight is atypical, when compared with corresponding data for the same phase for other similar flights. A flight signature is computed using continuous-valued and discrete-valued flight parameters for the selected flight parameters and is optionally compared with a statistical distribution of other observed flight signatures, yielding atypicality scores for the same phase for other similar flights. A cluster analysis is optionally applied to the flight signatures to define an optimal collection of clusters. A level of atypicality for a selected flight is estimated, based upon an index associated with the cluster analysis.

Effect of first dimension phase selectivity in online comprehensive two dimensional liquid chromatography (LC × LC)

PubMed Central

Gu, Haiwei; Huang, Yuan; Filgueira, Marcelo; Carr, Peter W.

2012-01-01

In this study, we examined the effect of first dimension column selectivity in reversed phase (RP) online comprehensive two dimensional liquid chromatography (LC × LC). The second dimension was always a carbon clad metal oxide reversed phase material. The hydrophobic subtraction model (HSM) and the related phase selective triangles were used to guide the selection of six different RP first dimension columns. Various kinds of samples were investigated and thus two different elution conditions were needed to cause full elution from the first dimension columns. We compared LC × LC chromatograms, contours plots, and fcoverage plots by measuring peak capacities, peak numbers, relative spatial coverage, correlation values, etc. The major finding of this study is that the carbon phase due to its rather different selectivity from other reversed phases is reasonably orthogonal to a variety of common types of bonded reversed phases. Thus quite surprisingly the six different first dimension stationary phases all showed generally similar separation patterns when paired to the second dimension carbon phase. This result greatly simplifies the task of choosing the correct pair of phases for RP × RP. PMID:21840009

Probability of success for phase III after exploratory biomarker analysis in phase II.

PubMed

Götte, Heiko; Kirchner, Marietta; Sailer, Martin Oliver

2017-05-01

The probability of success or average power describes the potential of a future trial by weighting the power with a probability distribution of the treatment effect. The treatment effect estimate from a previous trial can be used to define such a distribution. During the development of targeted therapies, it is common practice to look for predictive biomarkers. The consequence is that the trial population for phase III is often selected on the basis of the most extreme result from phase II biomarker subgroup analyses. In such a case, there is a tendency to overestimate the treatment effect. We investigate whether the overestimation of the treatment effect estimate from phase II is transformed into a positive bias for the probability of success for phase III. We simulate a phase II/III development program for targeted therapies. This simulation allows to investigate selection probabilities and allows to compare the estimated with the true probability of success. We consider the estimated probability of success with and without subgroup selection. Depending on the true treatment effects, there is a negative bias without selection because of the weighting by the phase II distribution. In comparison, selection increases the estimated probability of success. Thus, selection does not lead to a bias in probability of success if underestimation due to the phase II distribution and overestimation due to selection cancel each other out. We recommend to perform similar simulations in practice to get the necessary information about the risk and chances associated with such subgroup selection designs. Copyright © 2017 John Wiley & Sons, Ltd.

Performance analysis of microcomputer based differential protection of UHV lines under selective phase switching

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

Bhatti, A.A.

1990-04-01

This paper examines the effects of primary and secondary fault quantities as well s of mutual couplings of neighboring circuits on the sensitivity of operation and threshold settings of a microcomputer based differential protection of UHV lines under selective phase switching. Microcomputer based selective phase switching allows the disconnection of minimum number of phases involved in a fault and requires the autoreclosing of these phases immediately after the extinction of secondary arc. During a primary fault a heavy current contribution to the healthy phases tends to cause an unwanted tripping. Faulty phases physically disconnected constitute an isolated fault which beingmore » coupled to the system affects the current and voltage levels of the healthy phases still retained in the system and may cause an unwanted tripping. The microcomputer based differential protection, appears to have poor performance when applied to uncompensated lines employing selective pole switching.« less

Cooper River Rediversion Project. Lake Moultrie and Santee River, South Carolina. Intake and Tailrace Canals.

DTIC Science & Technology

1976-06-01

0 COM’PLE’t 01 No N’-tcRO~TATIC. ŘLAD F.0Uv4DATlON4 PRevuRr- + L. *I. .;Appko/%C-NH 5. oo *PS f~ ;:.. .~0NlION -FULL 14’lC7, AULIC . WILAD . 7A IL W...Data 3 1 HYDROLOGY Basin Description 4 l Topography 6 2 Stream Characteristics 7 2 Climate 8 2 Precipitation 9 2 Storms of Record 10 3 Runoff and...swampy areas as they reach the Coastal Plain. Slopes of the rivers in the Coastal Plain Province average about 0.6 foot per mile. 6. Climate . The Santee

Evaluation of one dimensional analytical models for vegetation canopies

NASA Technical Reports Server (NTRS)

Goel, Narendra S.; Kuusk, Andres

1992-01-01

The SAIL model for one-dimensional homogeneous vegetation canopies has been modified to include the specular reflectance and hot spot effects. This modified model and the Nilson-Kuusk model are evaluated by comparing the reflectances given by them against those given by a radiosity-based computer model, Diana, for a set of canopies, characterized by different leaf area index (LAI) and leaf angle distribution (LAD). It is shown that for homogeneous canopies, the analytical models are generally quite accurate in the visible region, but not in the infrared region. For architecturally realistic heterogeneous canopies of the type found in nature, these models fall short. These shortcomings are quantified.

Thrombus aspiration catheter is a Dottering balloon.

PubMed

Sheshagiri Rao, D; Barik, Ramachandra; Prasad, Akula Siva

2016-01-01

Coronary angiogram in a young man with history of STEMI with delayed presentation revealed subtotal occlusion of left anterior descending artery (LAD) with large thrombotic filling defect distal to the critical lesion. PCI was preferred without delay because of ongoing chest pain. Several runs of thrombus aspiration failed to detect any visible thrombus. However, the immediate angiogram after thrombus aspiration showed complete distal embolization of the thrombus which could have been achieved by Dottering or balloon dilatation. In contrary to the general perception, does thrombus aspiration push more thrombus than it can aspirate? Copyright © 2016 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Hydrological excitation of polar motion

NASA Astrophysics Data System (ADS)

Nastula, Y.; Kolaczek, B.

2006-08-01

Hydrological excitation of the polar motion (HAM) were computed from the available recently hydrological data series (NCEP, ECMWF, CPC water storage and LaD World simulations of global continental water) and compared. Time variable seasonal spectra of these hydrological excitation functions and of the geodetic excitation function of polar motion computed from the polar motion COMB03 data were compared showing big differences in their temporal characteristics and the necessity of the further improvement of the HAM models. Seasonal oscillations of the global geophysical excitation functions (AAM + OAM + HAM) and their time variations were compared also. These hydrological excitation functions do not close the budget of the global geophysical excitation function of polar motion.

500 Contractors Receiving the Largest Dollar Volume of Prime Contract Awards for RDT&E (Research, Development, Test and Evaluation), Fiscal Year 1977.

DTIC Science & Technology

1977-01-01

ENGINEERING INC * 2 e GENERAL i:tT~ LU l4 e DEWEEY ELECI-ONICS CORP It 160 E GENERAL I % 5TkUM E’t: 61.mP 9 43 DIGITAL CCt.MUNICATIONS C3O* 49 8...NORTHROP CORP • 63 h RANE CORP -- , 424 N NORTHWESTERN UNIVERSITY 4 .27 E RAYCLPN INOUSTKIES INC 383 8 OCEAN DATA SYSTEMS INC • 481 8 RAYPhNO ENGINEERING ...CONTROL INC . 344 h VIRGLNIA UNIVEkSITY (.;F 268 a SYSTEMS ENGINE -ING LAdORATONIES * 366 e VISIDYNE INC 26? 8 SYSTEMS EXPLOQATICN INC * 62 e VOUGHT CORP

Left-main restenosis in the DES era-a call for action.

PubMed

di Palma, Gaetano; Cortese, Bernardo

2017-11-10

Percutaneous treatment of the unprotected left main trunk (ULM), defined as a vessel without patent bypass graft either to the left circumflex (LCX) or left anterior descending (LAD) artery, has gained a precise role thanks to recent scientific evidence. Although new generation drug-eluting stents have already proven to be safer, there is still a consistent risk of restenosis and late adverse events. The optimal management of a ULM restenosis is still debated. Here we aim at presenting a review of the available data in literature and show our choice for treating it. Copyright © 2017 Elsevier Inc. All rights reserved.

GAS PHASE SELECTIVE PHOTOXIDATION OF ALCOHOLS USING LIGHT-ACTIVATED TITANIUM DIOXIDE AND MOLECULAR OXYGEN

EPA Science Inventory

Gas Phase Selective Oxidation of Alcohols Using Light-Activated Titanium Dioxide and Molecular Oxygen

Gas phase selective oxidations of various primary and secondary alcohols are studied in an indigenously built stainless steel up-flow photochemical reactor using ultravi...

Retention properties of novel beta-CD bonded stationary phases in reversed-phase HPLC mode.

PubMed

Zhao, Yanyan; Guo, Zhimou; Zhang, Yongping; Xue, Xingya; Xu, Qing; Li, Xiuling; Liang, Xinmiao; Zhang, Yukui

2009-05-15

With the given special structures, the CD bonded stationary phases are expected to have complementary retention properties with conventional C18 stationary phase, which will be helpful to enhance the polar selectivity in RP mode separation. In this work, two beta-cyclodextrin (beta-CD) bonded stationary phases for reversed-phase HPLC, including 1, 12-dodecyldiol linked beta-CD stationary phase (CD1) and olio (ethylene glycol) (OEG) linked beta-CD stationary phase (CD2), have been synthesized via click chemistry. The resulting materials were characterized with FT-IR and elemental analysis, which proved the successful immobilization of ligands. The similarities and differences in retention characteristics between the CD and C18 stationary phases have been elucidated by using comparative linear solvation energy relationships (LSERs). The force related to solute McGowan volume has no significant difference, while the hydrogen bonding and dipolar interactions between solutes and CD stationary phases are stronger than between solutes and C18, which is attributed to the special structures (CD and triazole groups) of CD stationary phases. Chemical origins are interpreted by comparison between CD1 and CD2. Similar dispersive interactions of CD1 and CD2 are attributed to their similar length of spacer arms. CD2 which contains OEG spacer arm has relative weaker HBD acidity but stronger HBA basicity. CD stationary phases display no serious different methylene selectivity and higher polar selectivity than in the case of C18. Higher acid selectivity and lower basic selectivity are observed on CD2 than on CD1. Distinctive retention properties and good complementary separation selectivity to C18 make the novel CD bonded stationary phases available for more application in RPLC.

Quantitative assessment on coronary computed tomography angiography (CCTA) image quality: comparisons between genders and different tube voltage settings

PubMed Central

Chian, Teo Chee; Nassir, Norziana Mat; Ibrahim, Mohd Izuan; Yusof, Ahmad Khairuddin Md

2017-01-01

Background This study was carried out to quantify and compare the quantitative image quality of coronary computed tomography angiography (CCTA) between genders as well as between different tube voltages scan protocols. Methods Fifty-five cases of CCTA were collected retrospectively and all images including reformatted axial images at systolic and diastolic phases as well as images with curved multi planar reformation (cMPR) were obtained. Quantitative image quality including signal intensity, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of right coronary artery (RCA), left anterior descending artery (LAD), left circumflex artery (LCx) and left main artery (LM) were quantified using Analyze 12.0 software. Results Six hundred and fifty-seven coronary arteries were evaluated. There were no significant differences in any quantitative image quality parameters between genders. 100 kilovoltage peak (kVp) scanning protocol produced images with significantly higher signal intensity compared to 120 kVp scanning protocol (P<0.001) in all coronary arteries in all types of images. Higher SNR was also observed in 100 kVp scan protocol in all coronary arteries except in LCx where 120 kVp showed better SNR than 100 kVp. Conclusions There were no significant differences in image quality of CCTA between genders and different tube voltages. Lower tube voltage (100 kVp) scanning protocol is recommended in clinical practice to reduce the radiation dose to patient. PMID:28275559

3D tomographic reconstruction of the terrestrial exosphere and its time-dependent coupling to the magnetospheric ring current

NASA Astrophysics Data System (ADS)

Waldrop, L.; Cucho-Padin, G.; Ilie, R.

2017-12-01

Charge exchange collisions between ring current ions and hydrogen (H) atoms in the outer exosphere serve to dissipate magnetospheric energy, particularly during the slow recovery phase of geomagnetic storms, through the generation of energetic neutral atoms (ENAs) which escape the system. As a result, knowledge of the spatial distribution and temporal variability of exospheric H density is critical for reliable interpretation of ENA flux measurements as well as for accurate modeling of the ring current. Although numerous theoretical, numerical, and empirical H distributions have been used for such analyses, their reliance on ad hoc or unphysical assumptions, together with their inherently static formulations, is a source of significant uncertainty. Our recent development of a robust tomographic technique for the model-independent estimation of global exospheric H density from optical remote sensing data overcomes the limitations of past analysis and enables an unprecedented investigation of global exospheric and ring current dynamics. Here, we present sample results of our 3D, time-dependent reconstructions of exospheric structure, derived from measurements of resonantly scattered solar Lyman-alpha (121.6 nm) photons acquired by the Lyman-alpha detectors (LADs) onboard NASA's Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) mission. We use the Hot Electron and Ion Drift Integrator (HEIDI) kinetic model of the ring current to investigate the charge exchange interactions between the resulting H density distribution and ring current ions and generate synthetic images of ENA flux for comparison with those measured by TWINS.

48 CFR 1852.217-72 - Phased acquisition using progressive competition down-selection procedures.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Phase 2 synopsis, and NASA will provide that source to all the material furnished to the Phase 1... the date upon which Phase 2 proposals are requested. Any such changes in evaluation factors will not... procurement using a progressive competition down-selection technique between phases. In this technique, two or...

48 CFR 1852.217-72 - Phased acquisition using progressive competition down-selection procedures.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Phase 2 synopsis, and NASA will provide that source to all the material furnished to the Phase 1... the date upon which Phase 2 proposals are requested. Any such changes in evaluation factors will not... procurement using a progressive competition down-selection technique between phases. In this technique, two or...

Continuous and discontinuous phase transitions in the evolution of a polygenic trait under stabilizing selective pressure

NASA Astrophysics Data System (ADS)

Fierro, Annalisa; Cocozza, Sergio; Monticelli, Antonella; Scala, Giovanni; Miele, Gennaro

2017-06-01

The presence of phenomena analogous to phase transition in Statistical Mechanics has been suggested in the evolution of a polygenic trait under stabilizing selection, mutation and genetic drift. By using numerical simulations of a model system, we analyze the evolution of a population of N diploid hermaphrodites in random mating regime. The population evolves under the effect of drift, selective pressure in form of viability on an additive polygenic trait, and mutation. The analysis allows to determine a phase diagram in the plane of mutation rate and strength of selection. The involved pattern of phase transitions is characterized by a line of critical points for weak selective pressure (smaller than a threshold), whereas discontinuous phase transitions, characterized by metastable hysteresis, are observed for strong selective pressure. A finite-size scaling analysis suggests the analogy between our system and the mean-field Ising model for selective pressure approaching the threshold from weaker values. In this framework, the mutation rate, which allows the system to explore the accessible microscopic states, is the parameter controlling the transition from large heterozygosity ( disordered phase) to small heterozygosity ( ordered one).

48 CFR 36.301 - Use of two-phase design-build selection procedures.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Use of two-phase design-build selection procedures. 36.301 Section 36.301 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Two-Phase Design-Build Selection Procedures 36.301...

Clinical evaluation of new automatic coronary-specific best cardiac phase selection algorithm for single-beat coronary CT angiography.

PubMed

Wang, Hui; Xu, Lei; Fan, Zhanming; Liang, Junfu; Yan, Zixu; Sun, Zhonghua

2017-01-01

The aim of this study was to evaluate the workflow efficiency of a new automatic coronary-specific reconstruction technique (Smart Phase, GE Healthcare-SP) for selection of the best cardiac phase with least coronary motion when compared with expert manual selection (MS) of best phase in patients with high heart rate. A total of 46 patients with heart rates above 75 bpm who underwent single beat coronary computed tomography angiography (CCTA) were enrolled in this study. CCTA of all subjects were performed on a 256-detector row CT scanner (Revolution CT, GE Healthcare, Waukesha, Wisconsin, US). With the SP technique, the acquired phase range was automatically searched in 2% phase intervals during the reconstruction process to determine the optimal phase for coronary assessment, while for routine expert MS, reconstructions were performed at 5% intervals and a best phase was manually determined. The reconstruction and review times were recorded to measure the workflow efficiency for each method. Two reviewers subjectively assessed image quality for each coronary artery in the MS and SP reconstruction volumes using a 4-point grading scale. The average HR of the enrolled patients was 91.1±19.0bpm. A total of 204 vessels were assessed. The subjective image quality using SP was comparable to that of the MS, 1.45±0.85 vs 1.43±0.81 respectively (p = 0.88). The average time was 246 seconds for the manual best phase selection, and 98 seconds for the SP selection, resulting in average time saving of 148 seconds (60%) with use of the SP algorithm. The coronary specific automatic cardiac best phase selection technique (Smart Phase) improves clinical workflow in high heart rate patients and provides image quality comparable with manual cardiac best phase selection. Reconstruction of single-beat CCTA exams with SP can benefit the users with less experienced in CCTA image interpretation.

A Dual-Stage Two-Phase Model of Selective Attention

ERIC Educational Resources Information Center

Hubner, Ronald; Steinhauser, Marco; Lehle, Carola

2010-01-01

The dual-stage two-phase (DSTP) model is introduced as a formal and general model of selective attention that includes both an early and a late stage of stimulus selection. Whereas at the early stage information is selected by perceptual filters whose selectivity is relatively limited, at the late stage stimuli are selected more efficiently on a…

48 CFR 1852.217-71 - Phased acquisition using down-selection procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

... NASA reserves the right to change them at any time up to and including the date upon which Phase 2... phases. In this technique, two or more contractors will be selected for Phase 1. It is expected that the single contractor for Phase 2 will be chosen from among these contractors after a competitive down...

48 CFR 1852.217-71 - Phased acquisition using down-selection procedures.

Code of Federal Regulations, 2011 CFR

2011-10-01

... NASA reserves the right to change them at any time up to and including the date upon which Phase 2... phases. In this technique, two or more contractors will be selected for Phase 1. It is expected that the single contractor for Phase 2 will be chosen from among these contractors after a competitive down...

23 CFR 636.202 - When are two-phase design-build selection procedures appropriate?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 23 Highways 1 2011-04-01 2011-04-01 false When are two-phase design-build selection procedures appropriate? 636.202 Section 636.202 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS DESIGN-BUILD CONTRACTING Selection Procedures, Award Criteria § 636.202 When are two-phase design-build...

Cadmium Alternatives for High-Strength Steel JTP - Phase 2

DTIC Science & Technology

2008-02-27

Project Overview Objective • Assess DoD- selected Cadmium alternatives in accordance with the DoD-approved Joint Test Protocol (JTP) for both...HE and adhesion testing): NAVAIR (complete) – Phase II (JTP test matrix): AFRL/CTC – Phase III (Testing for Threaded Fasteners): ARL • Selection of...Curry • Hill AFB – Mr. Nate Hughes • Alumiplate – Mr. Gus Vallejo • Marshall Labs – Mr. John Marshall U.S. AIR FORCE Phase I Overview and Selection

Selectivity optimization in green chromatography by gradient stationary phase optimized selectivity liquid chromatography.

PubMed

Chen, Kai; Lynen, Frédéric; De Beer, Maarten; Hitzel, Laure; Ferguson, Paul; Hanna-Brown, Melissa; Sandra, Pat

2010-11-12

Stationary phase optimized selectivity liquid chromatography (SOSLC) is a promising technique to optimize the selectivity of a given separation by using a combination of different stationary phases. Previous work has shown that SOSLC offers excellent possibilities for method development, especially after the recent modification towards linear gradient SOSLC. The present work is aimed at developing and extending the SOSLC approach towards selectivity optimization and method development for green chromatography. Contrary to current LC practices, a green mobile phase (water/ethanol/formic acid) is hereby preselected and the composition of the stationary phase is optimized under a given gradient profile to obtain baseline resolution of all target solutes in the shortest possible analysis time. With the algorithm adapted to the high viscosity property of ethanol, the principle is illustrated with a fast, full baseline resolution for a randomly selected mixture composed of sulphonamides, xanthine alkaloids and steroids. Copyright © 2010 Elsevier B.V. All rights reserved.

Selectivity in reversed-phase separations: general influence of solvent type and mobile phase pH.

PubMed

Neue, Uwe D; Méndez, Alberto

2007-05-01

The influence of the mobile phase on retention is studied in this paper for a group of over 70 compounds with a broad range of multiple functional groups. We varied the pH of the mobile phase (pH 3, 7, and 10) and the organic modifier (methanol, acetonitrile (ACN), and tetrahydrofuran (THF)), using 15 different stationary phases. In this paper, we describe the overall retention and selectivity changes observed with these variables. We focus on the primary effects of solvent choice and pH. For example, transfer rules for solvent composition resulting in equivalent retention depend on the packing as well as on the type of analyte. Based on the retention patterns, one can calculate selectivity difference values for different variables. The selectivity difference is a measure of the importance of the different variables involved in method development. Selectivity changes specific to the type of analyte are described. The largest selectivity differences are obtained with pH changes.

Device and method for creating Gaussian aberration-corrected electron beams

DOEpatents

McMorran, Benjamin; Linck, Martin

2016-01-19

Electron beam phase gratings have phase profiles that produce a diffracted beam having a Gaussian or other selected intensity profile. Phase profiles can also be selected to correct or compensate electron lens aberrations. Typically, a low diffraction order produces a suitable phase profile, and other orders are discarded.

48 CFR 570.305 - Two-phase design-build selection procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Two-phase design-build... for Leasehold Interests in Real Property 570.305 Two-phase design-build selection procedures. (a) These procedures apply to acquisitions of leasehold interests if you use the two-phase design-build...

Low Cost 2-D Heatshield Materials

DTIC Science & Technology

1982-03-05

1 -4 - -,--. WE: 190 LUU LU w 4A (A IC a -’ I- 0 3c z L U LLJ u0 ud Lad 10 .- qVa . IC -Ab In this test, a...REPOR.’ Dn _1,EHTA’ 1 .;ij PAGE DRSCMLý%IGF" ____ __4 1 33 813C M~J.~~ŽOP Ř. ’rT.19ddsmto S. Type F1@60pNIaOPobw~, aOcovItNK Final Technical Report May...IYD13NUBROPAE Redstone ArseralL.AL 35ý1 __20 1 -MONO’. CRING AG.:hiY HAM41 & AVOR&;S(11 dill. il I.,. Can-r..INA, OflICS) IS- SECUWI *Y CLASS. (@ 1

Monitoring the Crab Nebula with LOFT

NASA Technical Reports Server (NTRS)

Wilson-Hodge, Colleen A.

2012-01-01

From 2008-2010, the Crab Nebula was found to decline by 7% in the 15-50 keV band, consistently in Fermi GBM, INTEGRAL IBIS, SPI, and JEMX, RXTE PCA, and Swift BAT. From 2001-2010, the 15-50 keV flux from the Crab Nebula typically varied by about 3.5% per year. Analysis of RXTE PCA data suggests possible spectral variations correlated with the flux variations. I will present estimates of the LOFT sensitivity to these variations. Prior to 2001 and since 2010, the observed flux variations have been much smaller. Monitoring the Crab with the LOFT WFM and LAD will provide precise measurements of flux variations in the Crab Nebula if it undergoes a similarly active episode.

Kinetic Study of Mass Transfer by Sodium Hydroxide in Nickel Under Free-convection Conditions /by Don R. Mosher and Robert A. Lad

NASA Technical Reports Server (NTRS)

Mosher, Don R; Lad, Robert A

1954-01-01

An investigation was conducted using static capsules fabricated from "L" nickel tubing to determine the effect of temperature level, temperature gradient, and test duration on corrosion and mass transfer by molten sodium hydroxide under free-convection conditions. A base temperature range from 1000 degrees to 1600 degrees F with temperature differences to 500 degrees was studied. The rate of mass transfer was found to be strongly dependent on both temperature level and gradient. The rate shows little tendency to decrease for test durations up to 200 hours, although the concentration of nickel in the melt approaches a limited value after 100 hours.

Annual Report on Electronics Research at The University of Texas at Austin.

DTIC Science & Technology

1979-07-15

Radiative Recom-bination to Fo rm HD and HeH “ , Che mical Phy s ic s 2 8, pp. 441- 446 , 1978. * B. M il ler and M . F ink , “Effect of Finite...aedl Porn ‘ton~~sA th , Ml 077 0 0 Pont lolvoin , VA 22060 l’oaandry CS Attn M t nnile lAD : ..a n d Coaandrt ‘ ‘1 tres A1 .,‘brr I. tnt.,,.. Labor.tc...ts 88002 Porn NO,~~ t,th , IL! 011) 1 Ned Device. Lab *106 : 08011-ND (~~~. I g. Frt.de.lnn( Pert Nn.a’s,th , 6.2 01105 • The joint Service. Te chni

AC Resonant charger with charge rate unrelated to primary power frequency

DOEpatents

Watson, Harold

1982-01-01

An AC resonant charger for a capacitive load, such as a PFN, is provided with a variable repetition rate unrelated to the frequency of a multi-phase AC power source by using a control unit to select and couple the phase of the power source to the resonant charger in order to charge the capacitive load with a phase that is the next to begin a half cycle. For optimum range in repetition rate and increased charging voltage, the resonant charger includes a step-up transformer and full-wave rectifier. The next phase selected may then be of either polarity, but is always selected to be of a polarity opposite the polarity of the last phase selected so that the transformer core does not saturate. Thyristors are used to select and couple the correct phase just after its zero crossover in response to a sharp pulse generated by a zero-crossover detector. The thyristor that is turned on then automatically turns off after a full half cycle of its associated phase input. A full-wave rectifier couples the secondary winding of the transformer to the load so that the load capacitance is always charged with the same polarity.

Ac resonant charger with charge rate unrelated to preimary power requency

DOEpatents

Not Available

1979-12-07

An ac resonant charger for a capacitive load, such as a pulse forming network (PFN), is provided with a variable repetition rate unrelated to the frequency of a multi-phase ac power source by using a control unit to select and couple the phase of the power source to the resonant charger in order to charge the capacitive load with a phase that is the next to begin a half cycle. For optimum range in repetition rate and increased charging voltage, the resonant charger includes a step-up transformer and full-wave rectifier. The next phase selected may then be of either polarity, but is always selected to be of a polarity opposite the polarity of the last phase selected so that the transformer core does not saturate. Thyristors are used to select and couple the correct phase just after its zero crossover in response to a sharp pulse generated by a zero-crossover detector. The thyristor that is turned on then automatically turns off after a full half cycle of its associated phase input. A full-wave rectifier couples the secondary winding of the transformer to the load so that the load capacitance is always charged with the same polarity.

Controllable phase transitions and novel selection rules in Josephson junctions with inherent orthogonality

NASA Astrophysics Data System (ADS)

Cheng, Qiang; Zhang, Kunhua; Ma, Hongyang

2018-03-01

We propose a new type of Josephson junction consisting of topologically nontrivial superconductors with inherent orthogonality and a ferromagnetic interface. It is found this type of junction can host rich ground states: 0 phase, π phase, 0 + π phase, φ0 phase and φ0 ± φ phase. Phase transitions can be controlled by changing the direction of the interfacial magnetization. Phase diagrams are presented in the orientation space. Novel selection rules for the lowest order current, sin ⁡ ϕ or cos ⁡ ϕ, of this kind of junction are derived. General conditions for the formation of various ground states are established, which possess guiding significance to the experimental design of required ground states for practical applications. We construct the succinct form of a Ginzburg-Landau type of free energy from the viewpoint of the interplay between topological superconductivity and ferromagnetism, which can immediately lead to the selection rules. The constructed terms are universally available to the topological Josephson junctions with or without inherent orthogonality reported recently. The spin supercurrent, its selection rules and their relations to the constructed energy are also investigated.

The hydrophilicity vs. ion interaction selectivity plot revisited: The effect of mobile phase pH and buffer concentration on hydrophilic interaction liquid chromatography selectivity behavior.

PubMed

Iverson, Chad D; Gu, Xinyun; Lucy, Charles A

2016-08-05

This work systematically investigates the selectivity changes on many HILIC phases from w(w)pH 3.7-6.8, at 5 and 25mM buffer concentrations. Hydrophilicity (kcytosine/kuracil) vs. ion interaction (kBTMA/kuracil) selectivity plots developed by Ibrahim et al. (J. Chromatogr. A 1260 (2012) 126-131) are used to investigate the effect of mobile phase changes on the selectivity of 18 HILIC columns from various classes. "Selectivity change plots" focus on the change in hydrophilicity and ion interaction that the columns exhibit upon changing mobile phase conditions. In general, the selectivity behavior of most HILIC columns is dominated by silanol activity. Minimal changes in selectivity are observed upon changing pH between w(w)pH 5 and 6.8. However, a reduction in ionic interaction is observed when the buffer concentration is increased at w(w)pH≥5.0 due to ionic shielding. Reduction of the w(w)pH to<5.0 results in decreasing cation exchange activity due to silanol protonation. Under all eluent conditions, the majority of phases show little change in their hydrophilicity. Copyright © 2016 Elsevier B.V. All rights reserved.

48 CFR 1852.217-72 - Phased acquisition using progressive competition down-selection procedures.

Code of Federal Regulations, 2012 CFR

2012-10-01

... responding to the Phase 2 synopsis, and NASA will provide that source to all the material furnished to the... to and including the date upon which Phase 2 proposals are requested. Any such changes in evaluation... procurement using a progressive competition down-selection technique between phases. In this technique, two or...

Method and system for selecting data sampling phase for self timed interface logic

DOEpatents

Hoke, Joseph Michael; Ferraiolo, Frank D.; Lo, Tin-Chee; Yarolin, John Michael

2005-01-04

An exemplary embodiment of the present invention is a method for transmitting data among processors over a plurality of parallel data lines and a clock signal line. A receiver processor receives both data and a clock signal from a sender processor. At the receiver processor a bit of the data is phased aligned with the transmitted clock signal. The phase aligning includes selecting a data phase from a plurality of data phases in a delay chain and then adjusting the selected data phase to compensate for a round-off error. Additional embodiments include a system and storage medium for transmitting data among processors over a plurality of parallel data lines and a clock signal line.

Dual-wavelength phase-shifting digital holography selectively extracting wavelength information from wavelength-multiplexed holograms.

PubMed

Tahara, Tatsuki; Mori, Ryota; Kikunaga, Shuhei; Arai, Yasuhiko; Takaki, Yasuhiro

2015-06-15

Dual-wavelength phase-shifting digital holography that selectively extracts wavelength information from five wavelength-multiplexed holograms is presented. Specific phase shifts for respective wavelengths are introduced to remove the crosstalk components and extract only the object wave at the desired wavelength from the holograms. Object waves in multiple wavelengths are selectively extracted by utilizing 2π ambiguity and the subtraction procedures based on phase-shifting interferometry. Numerical results show the validity of the proposed technique. The proposed technique is also experimentally demonstrated.

Characterization and applications of reversed-phase column selectivity based on the hydrophobic-subtraction model.

PubMed

Marchand, D H; Snyder, L R; Dolan, J W

2008-05-16

A total of 371 reversed-phase columns have now been characterized in terms of selectivity, based on five solute-column interactions (the hydrophobic-subtraction model). The present study illustrates the use of these data for interpreting peak-tailing and column stability. New insights are also provided concerning column selectivity as a function of ligand and silica type, and the selection of columns for orthogonal separations is re-examined. Some suggestions for the quality control of reversed-phase columns during manufacture are offered.

A polarized low-coherence interferometry demodulation algorithm by recovering the absolute phase of a selected monochromatic frequency.

PubMed

Jiang, Junfeng; Wang, Shaohua; Liu, Tiegen; Liu, Kun; Yin, Jinde; Meng, Xiange; Zhang, Yimo; Wang, Shuang; Qin, Zunqi; Wu, Fan; Li, Dingjie

2012-07-30

A demodulation algorithm based on absolute phase recovery of a selected monochromatic frequency is proposed for optical fiber Fabry-Perot pressure sensing system. The algorithm uses Fourier transform to get the relative phase and intercept of the unwrapped phase-frequency linear fit curve to identify its interference-order, which are then used to recover the absolute phase. A simplified mathematical model of the polarized low-coherence interference fringes was established to illustrate the principle of the proposed algorithm. Phase unwrapping and the selection of monochromatic frequency were discussed in detail. Pressure measurement experiment was carried out to verify the effectiveness of the proposed algorithm. Results showed that the demodulation precision by our algorithm could reach up to 0.15kPa, which has been improved by 13 times comparing with phase slope based algorithm.

The irreversible formation of palladium carbide during hydrogenation of 1-pentyne over silica-supported palladium nanoparticles: in situ Pd K and L3 edge XAS.

PubMed

Tew, Min Wei; Nachtegaal, Maarten; Janousch, Markus; Huthwelker, Thomas; van Bokhoven, Jeroen A

2012-04-28

The catalytically active phase of silica-supported palladium catalysts in the selective and non-selective hydrogenation of 1-pentyne was determined using in situ X-ray absorption spectroscopy at the Pd K and L(3) edges. Upon exposure to alkyne, a palladium carbide-like phase rapidly forms, which prevents hydrogen to diffuse into the bulk of the nano-sized particles. Both selective and non-selective hydrogenation occur over carbided particles. The palladium carbide-like phase is stable under reaction conditions and only partially decomposes under high hydrogen partial pressure. Non-selective hydrogenation to pentane is not indicative of hydride formation. The palladium carbide phase was detected in the EXAFS analysis and the K edge XANES showed representative features. This journal is © the Owner Societies 2012

The spatial structure of chronic morbidity: evidence from UK census returns.

PubMed

Dutey-Magni, Peter F; Moon, Graham

2016-08-24

Disease prevalence models have been widely used to estimate health, lifestyle and disability characteristics for small geographical units when other data are not available. Yet, knowledge is often lacking about how to make informed decisions around the specification of such models, especially regarding spatial assumptions placed on their covariance structure. This paper is concerned with understanding processes of spatial dependency in unexplained variation in chronic morbidity. 2011 UK census data on limiting long-term illness (LLTI) is used to look at the spatial structure in chronic morbidity across England and Wales. The variance and spatial clustering of the odds of LLTI across local authority districts (LADs) and middle layer super output areas are measured across 40 demographic cross-classifications. A series of adjacency matrices based on distance, contiguity and migration flows are tested to examine the spatial structure in LLTI. Odds are then modelled using a logistic mixed model to examine the association with district-level covariates and their predictive power. The odds of chronic illness are more dispersed than local age characteristics, mortality, hospitalisation rates and chance alone would suggest. Of all adjacency matrices, the three-nearest neighbour method is identified as the best fitting. Migration flows can also be used to construct spatial weights matrices which uncover non-negligible autocorrelation. Once the most important characteristics observable at the LAD-level are taken into account, substantial spatial autocorrelation remains which can be modelled explicitly to improve disease prevalence predictions. Systematic investigation of spatial structures and dependency is important to develop model-based estimation tools in chronic disease mapping. Spatial structures reflecting migration interactions are easy to develop and capture autocorrelation in LLTI. Patterns of spatial dependency in the geographical distribution of LLTI are not comparable across ethnic groups. Ethnic stratification of local health information is needed and there is potential to further address complexity in prevalence models by improving access to disaggregated data.

On the relationship between competitive flow and FFT analysis of the flow waves in the left internal mammary artery graft in the process of CABG.

PubMed

Mao, Boyan; Wang, Wenxin; Zhao, Zhou; Zhao, Xi; Li, Lanlan; Zhang, Huixia; Liu, Youjun

2016-12-28

During coronary artery bypass grafting (CABG), the ratio of powers of the fundamental frequency and its first harmonic (F0/H1) in fast Fourier transformation (FFT) analysis of the graft's flow waves has been used in the field of evaluation of the patency in anastomosis. But there is no report about using the FFT method to evaluate the magnitude of competitive flow. This study is aiming at exploring the relationship between competitive flow and FFT analysis of the flow waves in left internal mammary artery (LIMA) graft, and finding a new method to evaluate the magnitude of competitive flow. At first, establishing the CABG multiscale models of different stenosis in left anterior descending artery (LAD) to get different magnitude of competitive flows. Then, calculating the models by ANSYS-CFX and getting the flow waves in LIMA. Finally, analyzing the flow waves by FFT method and comparing the FFT results with the magnitude of competitive flow. There is no relationship between competitive flow and F0/H1. As for F0/H2 and F0/H3, they both increase with the reduction of the stenosis in LAD. But the increase of F0/H3 is not obviously enough and it can't identify the significant competitive flow clearly, so it can't be used as the evaluation index. It is found that F0/H2 increases obviously with the increase of the competitive flow and can identify the significant competitive flow. The FFT method can be used in the evaluation of competitive flow and the F0/H2 is the ideal index. High F0/H2 refers to the significant competitive flow. This method can be used during CABG to avoid the risk of competitive flow.