Self-consistent-field KKR-CPA calculations in the atomic-sphere approximations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, P.P. Gonis, A.; de Fontaine, D.
1991-12-03
We present a formulation of the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) for the treatment of substitutionally disordered alloys within the KKR atomic-sphere approximations (ASA). This KKR-ASA-CPA represents the first step toward the implementation of a full cell potential CPA, and combines the accuracy of the KKR-CPA method with the flexibility of treating complex crystal structures. The accuracy of this approach has been tested by comparing the self-consistent-field (SCF) KKR-ASA-CPA calculations of Cu-Pd alloys with experimental results and previous SCF-KKR-CPA calculations.
Electronic properties of excess Cr at Fe site in FeCr{sub 0.02}Se alloy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumar, Sandeep, E-mail: sandeepk.iitb@gmail.com; Singh, Prabhakar P.
2015-06-24
We have studied the effect of substitution of transition-metal chromium (Cr) in excess on Fe sub-lattice in the electronic structure of iron-selenide alloys, FeCr{sub 0.02}Se. In our calculations, we used Korringa-Kohn-Rostoker coherent potential approximation method in the atomic sphere approximation (KKR-ASA-CPA). We obtained different band structure of this alloy with respect to the parent FeSe and this may be reason of changing their superconducting properties. We did unpolarized calculations for FeCr{sub 0.02}Se alloy in terms of density of states (DOS) and Fermi surfaces. The local density approximation (LDA) is used in terms of exchange correlation potential.
First-principles study of electronic properties of Si doped FeSe{sub 0.9} alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumar, Sandeep, E-mail: sandeep@phy.iitb.ac.in; Singh, Prabhakar P.
2016-05-23
We have performed first-principles study of electronic and superconducting properties of FeSe{sub 0.9-x}Si{sub x} (x = 0.0, 0.05) alloys using Korringa-Kohn-Rostoker Atomic Sphere Approximation within the coherent potential approximation (KKR-ASA-CPA). In our calculations, we used the local density approximation (LDA) for the exchange correlation potential. Our calculations show that these alloys are nonmagnetic in nature. We found that the substitution of Si at Se site into FeSe{sub 0.9} made subtle affects in the electronic structure with respect to the parent FeSe. The results have been analyzed in terms of changes in the density of states (DOS), band structures, Fermi surfacesmore » and the superconducting transition temperature of FeSe{sub 0.9} and FeSe{sub 0.85}Si{sub 0.05} alloys.« less
First-principles study of electronic properties of FeSe{sub 1-x}S{sub x} alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumar, Sandeep, E-mail: sandeep@phy.iitb.ac.in; Singh, Prabhakar P.
2016-05-06
We have studied the electronic and superconducting properties of FeSe{sub 1-x}S{sub x} (x = 0.0, 0.04) alloys by first-principles calculations using the Korringa-Kohn-Rostoker Atomic Sphere Approximation within the coherent potential approximation (KKR-ASA-CPA). The electronic structure calculations show the ground states of S-doped FeSe to be nonmagnetic. We present the results of our unpolarized calculations for these alloys in terms of density of states (DOS), band structures, Fermi surfaces and the superconducting transition temperature of FeSe and FeSe{sub 0.96}S{sub 0.04} alloys. We find that the substitution of S at Se site into FeSe exhibit the subtle changes in the electronic structuremore » with respect to the parent FeSe. We have also estimated bare Sommerfeld constant (γ{sub b}), electron-phonon coupling constant (λ) and the superconducting transition temperature (T{sub c}) for these alloys, which were found to be in good agreement with experiments.« less
The All-Sky Automated Survey for Supernovae (ASAS-SN) Light Curve Server v1.0
NASA Astrophysics Data System (ADS)
Kochanek, C. S.; Shappee, B. J.; Stanek, K. Z.; Holoien, T. W.-S.; Thompson, Todd A.; Prieto, J. L.; Dong, Subo; Shields, J. V.; Will, D.; Britt, C.; Perzanowski, D.; Pojmański, G.
2017-10-01
The All-Sky Automated Survey for Supernovae (ASAS-SN) is working toward imaging the entire visible sky every night to a depth of V˜ 17 mag. The present data covers the sky and spans ˜2-5 years with ˜100-400 epochs of observation. The data should contain some ˜1 million variable sources, and the ultimate goal is to have a database of these observations publicly accessible. We describe here a first step, a simple but unprecedented web interface https://asas-sn.osu.edu/ that provides an up to date aperture photometry light curve for any user-selected sky coordinate. The V band photometry is obtained using a two-pixel (16.″0) radius aperture and is calibrated against the APASS catalog. Because the light curves are produced in real time, this web tool is relatively slow and can only be used for small samples of objects. However, it also imposes no selection bias on the part of the ASAS-SN team, allowing the user to obtain a light curve for any point on the celestial sphere. We present the tool, describe its capabilities, limitations, and known issues, and provide a few illustrative examples.
Band structure of the quaternary Heusler alloys ScMnFeSn and ScFeCoAl
NASA Astrophysics Data System (ADS)
Shanthi, N.; Teja, Y. N.; Shaji, Shephine M.; Hosamani, Shashikala; Divya, H. S.
2018-04-01
In our quest for materials with specific applications, a theoretical study plays an important role in predicting the properties of compounds. Heusler alloys or compounds are the most studied in this context. More recently, a lot of quaternary Heusler compounds are investigated for potential applications in fields like Spintronics. We report here our preliminary study of the alloys ScMnFeSn and ScFeCoAl, using the ab-initio linear muffin-tin orbital method within the atomic sphere approximation (LMTO-ASA). The alloy ScMnFeSn shows perfect half-metallicity, namely, one of the spins shows a metallic behaviour and the other spin shows semi-conducting behaviour. Such materials find application in devices such as the spin-transfer torque random access memory (STT-MRAM). In addition, the alloy ScMnFeSn is found to have an integral magnetic moment of 4 µB, as predicted by the Slater-Pauling rule. The alloy ScFeCoAl does not show half-metallicity.
Cuffari, Carmen; Pierce, David; Korczowski, Bartosz; Fyderek, Krzysztof; Van Heusen, Heather; Hossack, Stuart; Wan, Hong; Edwards, Alena Y Z; Martin, Patrick
2016-01-01
Limited data are available on mesalamine (5-aminosalicylic acid; 5-ASA) use in pediatric ulcerative colitis (UC). To evaluate pharmacokinetic and safety profiles of 5-ASA and metabolite acetyl-5-ASA (Ac-5-ASA) after once-daily, oral administration of multimatrix mesalamine to children and adolescents with UC. Participants (5-17 years of age; 18-82 kg, stratified by weight) with UC received multi-matrix mesalamine 30, 60, or 100 mg/kg/day once daily (to 4,800 mg/day) for 7 days. Blood samples were collected pre-dose on days 5 and 6. On days 7 and 8, blood and urine samples were collected and safety was evaluated. 5-ASA and Ac-5-ASA plasma and urine concentrations were analyzed by non-compartmental methods and used to develop a population pharmacokinetic model. Fifty-two subjects (21 [30 mg/kg]; 22 [60 mg/kg]; 9 [100 mg/kg]) were randomized. On day 7, systemic exposures of 5-ASA and Ac-5-ASA exhibited a dose-proportional increase between 30 and 60 mg/kg/day cohorts. For 30, 60, and 100 mg/kg/day doses, mean percentages of 5-ASA absorbed were 29.4%, 27.0%, and 22.1%, respectively. Simulated steady-state exposures and variabilities for 5-ASA and Ac-5-ASA (coefficient of variation approximately 50% and 40%-45%, respectively) were similar to those observed previously in adults at comparable doses. Treatment-emergent adverse events were reported by ten subjects. Events were similar among different doses and age groups with no new safety signals identified. Children and adolescents with UC receiving multimatrix mesalamine demonstrated 5-ASA and Ac-5-ASA pharmacokinetic profiles similar to historical adult data. Multimatrix mesalamine was well tolerated across all dose and age groups. ClinicalTrials.gov Identifier: NCT01130844.
Letter: The clinical course of patients with analgesic nephropathy.
Gault, M. H.
1975-01-01
Thirty-four patients with analgesic nephropathy were followed at intervals of 1 to 3 months with measurements of creatinine clearance and serum concentration of acetylsalicylic acid (ASA) for a total of 105 patient-years. Diagnostic criteria included total consumption of at least 2 kg of phenacetin and 3 kg of ASA, compatible tissue abnormality on biopsy and evidence of papillary necrosis on an intravenous pyelogram. Nephropathy was induced by the same compound analgesic containing ASA, pehnacetin, caffeine and codeine (APC&C) in 30. Phenacetin was removed from this preparation in 1970 and replaced by an approximately equal amount of ASA (ACC). Creatinine clearance remained unchanged or improved in 11 of 15 patients who stopped taking analgesics containing phenacetin or ASA and in 10 of 11 of those who continued to take the ACC preparation. In contrast, renal function deteriorated in seven of eight patients who continued to abuse APC&C analgesics. The results suggest that phenacetin is necessary for the major nephrotoxic effect of this APC&C combination, but that ASA is not absolved of some nephrotoxicity. PMID:1139519
Oberwittler, H; Baccara-Dinet, M
2006-06-01
Nicotinic acid (NA) is highly effective and widely used in the management of dyslipidaemia. For many patients, the side effect of flushing of the face and upper body leads to discontinuation. Flushing with NA is mediated by prostaglandins, and as acetyl salicylic acid (ASA, 'aspirin') is a highly effective inhibitor of prostaglandin synthesis, there is a rationale for its use to prevent or reduce the severity of NA-related flushing. This literature survey identified four studies specifically exploring the utility of ASA in preventing NA-related flushing in healthy volunteers. Twenty-three NA studies, where ASA was mandatory or optional within the protocol, and four studies, where background ASA therapy was reported in most participants, were also identified. Although the incidence of flushing in studies using ASA was often high, discontinuation rates due to flushing were low (mean 7.7%). This figure compares favourably with discontinuation rates with NA commonly reported in the literature (up to approximately 40%). There is good supportive evidence for the use of ASA in reducing the severity of NA-related flushing.
Cuffari, Carmen; Pierce, David; Korczowski, Bartosz; Fyderek, Krzysztof; Van Heusen, Heather; Hossack, Stuart; Wan, Hong; Edwards, Alena YZ; Martin, Patrick
2016-01-01
Background Limited data are available on mesalamine (5-aminosalicylic acid; 5-ASA) use in pediatric ulcerative colitis (UC). Aim To evaluate pharmacokinetic and safety profiles of 5-ASA and metabolite acetyl-5-ASA (Ac-5-ASA) after once-daily, oral administration of multimatrix mesalamine to children and adolescents with UC. Methods Participants (5–17 years of age; 18–82 kg, stratified by weight) with UC received multi-matrix mesalamine 30, 60, or 100 mg/kg/day once daily (to 4,800 mg/day) for 7 days. Blood samples were collected pre-dose on days 5 and 6. On days 7 and 8, blood and urine samples were collected and safety was evaluated. 5-ASA and Ac-5-ASA plasma and urine concentrations were analyzed by non-compartmental methods and used to develop a population pharmacokinetic model. Results Fifty-two subjects (21 [30 mg/kg]; 22 [60 mg/kg]; 9 [100 mg/kg]) were randomized. On day 7, systemic exposures of 5-ASA and Ac-5-ASA exhibited a dose-proportional increase between 30 and 60 mg/kg/day cohorts. For 30, 60, and 100 mg/kg/day doses, mean percentages of 5-ASA absorbed were 29.4%, 27.0%, and 22.1%, respectively. Simulated steady-state exposures and variabilities for 5-ASA and Ac-5-ASA (coefficient of variation approximately 50% and 40%–45%, respectively) were similar to those observed previously in adults at comparable doses. Treatment-emergent adverse events were reported by ten subjects. Events were similar among different doses and age groups with no new safety signals identified. Conclusion Children and adolescents with UC receiving multimatrix mesalamine demonstrated 5-ASA and Ac-5-ASA pharmacokinetic profiles similar to historical adult data. Multimatrix mesalamine was well tolerated across all dose and age groups. ClinicalTrials.gov Identifier: NCT01130844. PMID:26893546
Finite-size radiation force correction for inviscid spheres in standing waves.
Marston, Philip L
2017-09-01
Yosioka and Kawasima gave a widely used approximation for the acoustic radiation force on small liquid spheres surrounded by an immiscible liquid in 1955. Considering the liquids to be inviscid with negligible thermal dissipation, in their approximation the force on the sphere is proportional to the sphere's volume and the levitation position in a vertical standing wave becomes independent of the size. The analysis given here introduces a small correction term proportional to the square of the sphere's radius relative to the aforementioned small-sphere force. The significance of this term also depends on the relative density and sound velocity of the sphere. The improved approximation is supported by comparison with the exact partial-wave-series based radiation force for ideal fluid spheres in ideal fluids.
Li, Ruizhi; Fries, Susanne; Li, Xuanwen; Grosser, Tilo; Diamond, Scott L
2013-08-01
Microfluidic devices can create hemodynamic conditions for platelet assays. We validated an 8-channel device in a study of interdonor response to acetylsalicylic acid (ASA, aspirin) with whole blood from 28 healthy individuals. Platelet deposition was assessed before treatment or 24 h after ingestion of 325 mg ASA. Whole blood (plus 100 μmol/L H-d-Phe-Pro-Arg-chloromethylketone to inhibit thrombin) was further treated ex vivo with ASA (0-500 μmol/L) and perfused over fibrillar collagen for 300 s at a venous wall shear rate (200 s(-1)). Ex vivo ASA addition to blood drawn before aspirin ingestion caused a reduction in platelet deposition [half-maximal inhibitory concentration (IC50) approximately 10-20 μmol/L], especially between 150 and 300 s of perfusion, when secondary aggregation mediated by thromboxane was expected. Twenty-seven of 28 individuals displayed smaller deposits (45% mean reduction; range 10%-90%; P < 0.001) from blood obtained 24 h after ASA ingestion (no ASA added ex vivo). In replicate tests, an R value to score secondary aggregation [deposition rate from 150 to 300 s normalized by rate from 60 to 150 s] showed R < 1 in only 2 of 28 individuals without ASA ingestion, with R > 1 in only 3 of 28 individuals after 500 μmol/L ASA addition ex vivo. At 24 h after ASA ingestion, 21 of 28 individuals displayed poor secondary aggregation (R < 1) without ex vivo ASA addition, whereas the 7 individuals with residual secondary aggregation (R > 1) displayed insensitivity to ex vivo ASA addition. Platelet deposition was not correlated with platelet count. Ex vivo ASA addition caused similar inhibition at venous and arterial wall shear rates. Microfluidic devices quantified platelet deposition after ingestion or ex vivo addition of aspirin.
Lidar cross-sections of soot fractal aggregates: Assessment of equivalent-sphere models
NASA Astrophysics Data System (ADS)
Ceolato, Romain; Gaudfrin, Florian; Pujol, Olivier; Riviere, Nicolas; Berg, Matthew J.; Sorensen, Christopher M.
2018-06-01
This work assesses the ability of equivalent-sphere models to reproduce the optical properties of soot aggregates relevant for lidar remote sensing, i.e. the backscattering and extinction cross sections. Lidar cross-sections are computed with a spectral discrete dipole approximation model over the visible-to-infrared (400-5000 nm) spectrum and compared with equivalent-sphere approximations. It is shown that the equivalent-sphere approximation, applied to fractal aggregates, has a limited ability to calculate such cross-sections well. The approximation should thus be used with caution for the computation of broadband lidar cross-sections, especially backscattering, at small and intermediate wavelengths (e.g. UV to visible).
Henriquez, Natalia; Faúndez, Mario; Torres, Gloria; Castillo, Christian; Escanilla, Sebastián; Kemmerling, Ulrike; Morello, Antonio; López-Muñoz, Rodrigo A.; Maya, Juan D.
2013-01-01
Chagas' disease, produced by Trypanosoma cruzi, affects more than 8 million people, producing approximately 10,000 deaths each year in Latin America. Migration of people from endemic regions to developed countries has expanded the risk of infection, transforming this disease into a globally emerging problem. PGE2 and other eicosanoids contribute to cardiac functional deficits after infection with T. cruzi. Thus, the inhibition of host cyclooxygenase (COX) enzyme emerges as a potential therapeutic target. In vivo studies about the effect of acetylsalicylic acid (ASA) upon T. cruzi infection are controversial, and always report the effect of ASA at a single dose. Therefore, we aimed to analyze the effect of ASA at different doses in an in vivo model of infection and correlate it with the production of arachidonic acid metabolites. ASA decreased mortality, parasitemia, and heart damage in T. cruzi (Dm28c) infected mice, at the low doses of 25 and 50 mg/Kg. However, this effect disappeared when the high ASA doses of 75 and 100 mg/Kg were used. We explored whether this observation was related to the metabolic shift toward the production of 5-lipoxygenase derivatives, and although we did not observe an increase in LTB4 production in infected RAW cells and mice infected, we did find an increase in 15-epi-LXA4 (an ASA-triggered lipoxin). We also found high levels of 15-epi-LXA4 in T. cruzi infected mice treated with the low doses of ASA, while the high ASA doses decreased 15-epi-LXA4 levels. Importantly, 15-epi-LXA4 prevented parasitemia, mortality, and cardiac changes in vivo and restored the protective role in the treatment with a high dose of ASA. This is the first report showing the production of ASA-triggered lipoxins in T. cruzi infected mice, which demonstrates the role of this lipid as an anti-inflammatory molecule in the acute phase of the disease. PMID:23638194
On approximate formulas for the electrostatic force between two conducting spheres
NASA Astrophysics Data System (ADS)
Sliško, Josip; Brito-Orta, Raúl A.
1998-04-01
A series expression for the electrostatic force between two charged conducting spheres having equal radii and charges is derived using the method of electrical images. This expression is a special case of that for two spheres with arbitrary charges and radii, found by Maxwell using zonal harmonics. Keeping in mind the use of approximate formulas for the interpretation of classroom measurements of the electrostatic force between spheres, we comment on two incorrect approximate formulas and examine the contribution of the first few non-Coulomb terms of the correct formula by comparing with values obtained using a computational approach.
Schulz, Christian; Konrad, Ildiko; Sauer, Susanne; Orschiedt, Lena; Koellnberger, Maria; Lorenz, Reinhard; Walter, Ulrich; Massberg, Steffen
2008-01-01
Acetylsalicylic acid (ASA) and the thienopyridine clopidogrel are established anti-platelet drugs that significantly reduce secondary cardiovascular events in patients with manifest atherosclerosis. However, their impact on atherosclerotic lesion development remains controversial. Four-week-old ApoE-deficient mice were randomly assigned to four groups receiving a cholesterol diet together with either ASA (5 mg/kg), or clopidogrel (25 mg/kg), or a combination of both ASA and clopidogrel, or vehicle for 8-12 weeks. Using intravital microscopy we found that daily administration of ASA in combination with clopidogrel reduces platelet thrombus formation following rupture of atherosclerotic plaque in vivo by approximately 50%. However, therapy with ASA or clopidogrel alone, or in combination for a period of 8-12 weeks had no significant effect on adhesion of platelets to dysfunctional endothelial cells or on atherosclerotic lesion formation in the aortic root or the carotid artery. In conclusion, anti-platelet therapy is effective in reducing platelet adhesion and subsequent thrombus formation following rupture of atherosclerotic plaque in vivo. However, our data do not support a role of either drug in the primary prevention of atherosclerosis in ApoE-deficient mice.
Measurement of the Casimir Force between Two Spheres
NASA Astrophysics Data System (ADS)
Garrett, Joseph L.; Somers, David A. T.; Munday, Jeremy N.
2018-01-01
Complex interaction geometries offer a unique opportunity to modify the strength and sign of the Casimir force. However, measurements have traditionally been limited to sphere-plate or plate-plate configurations. Prior attempts to extend measurements to different geometries relied on either nanofabrication techniques that are limited to only a few materials or slight modifications of the sphere-plate geometry due to alignment difficulties of more intricate configurations. Here, we overcome this obstacle to present measurements of the Casimir force between two gold spheres using an atomic force microscope. Force measurements are alternated with topographical scans in the x -y plane to maintain alignment of the two spheres to within approximately 400 nm (˜1 % of the sphere radii). Our experimental results are consistent with Lifshitz's theory using the proximity force approximation (PFA), and corrections to the PFA are bounded using nine sphere-sphere and three sphere-plate measurements with spheres of varying radii.
Black-sphere approximation to nuclei and its application to reactions with neutron-rich nuclei
NASA Astrophysics Data System (ADS)
Kohama, Akihisa; Iida, Kei; Oyamatsu, Kazuhiro
2013-09-01
We briefly review our formula for a proton-nucleus total reaction cross section, σR, constructed in the black-sphere approximation of nuclei, in which a nucleus is viewed as a "black" sphere of radius "a". An extension to reactions involving neutron-rich nuclei is also reported.
Swimming of a linear chain with a cargo in an incompressible viscous fluid with inertia
NASA Astrophysics Data System (ADS)
Felderhof, B. U.
2017-01-01
An approximation to the added mass matrix of an assembly of spheres is constructed on the basis of potential flow theory for situations where one sphere is much larger than the others. In the approximation, the flow potential near a small sphere is assumed to be dipolar, but near the large sphere it involves all higher order multipoles. The analysis is based on an exact result for the potential of a magnetic dipole in the presence of a superconducting sphere. Subsequently, the approximate added mass hydrodynamic interactions are used in a calculation of the swimming velocity and rate of dissipation of linear chain structures consisting of a number of small spheres and a single large one, with account also of frictional hydrodynamic interactions. The results derived for periodic swimming on the basis of a kinematic approach are compared with the bilinear theory, valid for small amplitude of stroke, and with the numerical solution of the approximate equations of motion. The calculations interpolate over the whole range of scale number between the friction-dominated Stokes limit and the inertia-dominated regime.
Kandula, Mahesh; Sunil Kumar, K B; Palanichamy, Sivanesan; Rampal, Ashok
2016-11-01
Mesalamine (5-ASA) is one of the drugs indicated as first line therapy in ulcerative colitis for induction and maintenance of remission. Sulfasalazine and formulations of 5-ASA (pH-dependent and controlled release formulations) were developed to minimize the systemic absorption and maximize the delivery of the mesalamine to colon. Although, its efficacy and safety is well documented there are approximately 30% nonresponders to 5-ASA therapy. This necessitates the need for novel therapeutic options to improve the efficacy and safety of the currently available 5-ASA therapy. CLX-103 is a novel, patented prodrug molecular conjugate of mesalamine, eicosapentaenoic acid and caprylic acid designed to offer incremental benefits over the currently approved 5-ASA formulations. Results of in vitro and in vivo studies showed that CLX-103, was stable in simulated gastric fluid, but undergoes enzymatic hydrolysis in the small/large intestines to release the active moiety. Our data also showed that the active moiety is retained in the targeted intestinal tissues (ileum and colon) over a longer period of time in relation to sulfasalazine. The in vitro data supports the observed in vivo plasma kinetics of 5-ASA characterized by longer T max , low C max after the oral administration of CLX-103. Efficacy study of CLX-103 in acute dextran sodium sulfate (DSS) mouse colitis model showed improved potency measured as Disease Activity Index (DAI) and histological scores in the colon as compared to sulfasalazine. These findings indicate that CLX-103 could offer a differentiated drug product which is more efficacious and safer than the currently approved 5-ASA formulations in the treatment of inflammatory bowel diseases. Copyright © 2016 Elsevier B.V. All rights reserved.
Simple heuristic for the viscosity of polydisperse hard spheres
NASA Astrophysics Data System (ADS)
Farr, Robert S.
2014-12-01
We build on the work of Mooney [Colloids Sci. 6, 162 (1951)] to obtain an heuristic analytic approximation to the viscosity of a suspension any size distribution of hard spheres in a Newtonian solvent. The result agrees reasonably well with rheological data on monodispserse and bidisperse hard spheres, and also provides an approximation to the random close packing fraction of polydisperse spheres. The implied packing fraction is less accurate than that obtained by Farr and Groot [J. Chem. Phys. 131(24), 244104 (2009)], but has the advantage of being quick and simple to evaluate.
Lindén, Fredrik; Cederquist, Henrik; Zettergren, Henning
2016-11-21
We present exact analytical solutions for charge transfer reactions between two arbitrarily charged hard dielectric spheres. These solutions, and the corresponding exact ones for sphere-sphere interaction energies, include sums that describe polarization effects to infinite orders in the inverse of the distance between the sphere centers. In addition, we show that these exact solutions may be approximated by much simpler analytical expressions that are useful for many practical applications. This is exemplified through calculations of Langevin type cross sections for forming a compound system of two colliding spheres and through calculations of electron transfer cross sections. We find that it is important to account for dielectric properties and finite sphere sizes in such calculations, which for example may be useful for describing the evolution, growth, and dynamics of nanometer sized dielectric objects such as molecular clusters or dust grains in different environments including astrophysical ones.
Beyond-proximity-force-approximation Casimir force between two spheres at finite temperature
NASA Astrophysics Data System (ADS)
Bimonte, Giuseppe
2018-04-01
A recent experiment [J. L. Garrett, D. A. T. Somers, and J. N. Munday, Phys. Rev. Lett. 120, 040401 (2018), 10.1103/PhysRevLett.120.040401] measured for the first time the gradient of the Casimir force between two gold spheres at room temperature. The theoretical analysis of the data was carried out using the standard proximity force approximation (PFA). A fit of the data, using a parametrization of the force valid for the sphere-plate geometry, was used by the authors to place a bound on deviations from PFA. Motivated by this work, we compute the Casimir force between two gold spheres at finite temperature. The semianalytic formula for the Casimir force that we construct is valid for all separations, and can be easily used to interpret future experiments in both the sphere-plate and sphere-sphere configurations. We describe the correct parametrization of the corrections to PFA for two spheres that should be used in data analysis.
Can we use the equivalent sphere model to approximate organ doses in space radiation environments?
NASA Astrophysics Data System (ADS)
Lin, Zi-Wei
For space radiation protection one often calculates the dose or dose equivalent in blood forming organs (BFO). It has been customary to use a 5cm equivalent sphere to approximate the BFO dose. However, previous studies have concluded that a 5cm sphere gives a very different dose from the exact BFO dose. One study concludes that a 9cm sphere is a reasonable approximation for the BFO dose in solar particle event (SPE) environments. In this study we investigate the reason behind these observations and extend earlier studies by studying whether BFO, eyes or the skin can be approximated by the equivalent sphere model in different space radiation environments such as solar particle events and galactic cosmic ray (GCR) environments. We take the thickness distribution functions of the organs from the CAM (Computerized Anatomical Man) model, then use a deterministic radiation transport to calculate organ doses in different space radiation environments. The organ doses have been evaluated with a water or aluminum shielding from 0 to 20 g/cm2. We then compare these exact doses with results from the equivalent sphere model and determine in which cases and at what radius parameters the equivalent sphere model is a reasonable approximation. Furthermore, we propose to use a modified equivalent sphere model with two radius parameters to represent the skin or eyes. For solar particle events, we find that the radius parameters for the organ dose equivalent increase significantly with the shielding thickness, and the model works marginally for BFO but is unacceptable for eyes or the skin. For galactic cosmic rays environments, the equivalent sphere model with one organ-specific radius parameter works well for the BFO dose equivalent, marginally well for the BFO dose and the dose equivalent of eyes or the skin, but is unacceptable for the dose of eyes or the skin. The BFO radius parameters are found to be significantly larger than 5 cm in all cases, consistent with the conclusion of an earlier study. The radius parameters for the dose equivalent in GCR environments are approximately between 10 and 11 cm for the BFO, 3.7 to 4.8 cm for eyes, and 3.5 to 5.6 cm for the skin; while the radius parameters are between 10 and 13 cm for the BFO dose. In the proposed modified equivalent sphere model, the range of each of the two radius parameters for the skin (or eyes) is much tighter than that in the equivalent sphere model with one radius parameter. Our results thus show that the equivalent sphere model works better in galactic cosmic rays environments than in solar particle events. The model works well or marginally well for BFO but usually does not work for eyes or the skin. A modified model with two radius parameters works much better in approximating the dose and dose equivalent in eyes or the skin.
NASA Technical Reports Server (NTRS)
Jaeckel, Louis A.
1988-01-01
In Kanerva's Sparse Distributed Memory, writing to and reading from the memory are done in relation to spheres in an n-dimensional binary vector space. Thus it is important to know how many points are in the intersection of two spheres in this space. Two proofs are given of Wang's formula for spheres of unequal radii, and an integral approximation for the intersection in this case.
Ulcerative proctitis: an update on the pharmacotherapy and management.
Gecse, Krisztina B; Lakatos, Peter L
2014-08-01
Ulcerative colitis (UC) presents as proctitis in approximately a quarter of the patients. It may progress into left-sided or extensive colitis in up to 50% of cases upon long-term follow-up. Currently available data on ulcerative proctitis are summarized and critically reviewed. Extensive literature search (MEDLINE) was performed to identify relevant articles up to March 2014. The short-term goal of the treatment in UC is to induce remission, whereas long-term goals are to maintain remission and prevent disease progression. Topically administered 5-aminosalicylates (5-ASA) and corticosteroids are effective in the treatment of proctitis, although they seem to be underused in everyday practice. Locally administered 5-ASA preparations are more effective than oral compounds. The combination of topical and oral 5-ASA and steroids should be considered for escalation of treatment. Refractory patients should be re-evaluated to exclude for compliance failures, infections or proximal disease extent. True refractory or steroid-dependent patients may require immunomodulators or biological therapy. Alternative medicine can be used complementarily, while experimental approaches are reserved for patients failing conventional medication. Proctocolectomy may be the last resort of treatment. Upon long-term, 5-ASA maintenance treatment is indicated in all UC cases to prevent relapse and disease progression.
An asymptotically consistent approximant method with application to soft- and hard-sphere fluids.
Barlow, N S; Schultz, A J; Weinstein, S J; Kofke, D A
2012-11-28
A modified Padé approximant is used to construct an equation of state, which has the same large-density asymptotic behavior as the model fluid being described, while still retaining the low-density behavior of the virial equation of state (virial series). Within this framework, all sequences of rational functions that are analytic in the physical domain converge to the correct behavior at the same rate, eliminating the ambiguity of choosing the correct form of Padé approximant. The method is applied to fluids composed of "soft" spherical particles with separation distance r interacting through an inverse-power pair potential, φ = ε(σ∕r)(n), where ε and σ are model parameters and n is the "hardness" of the spheres. For n < 9, the approximants provide a significant improvement over the 8-term virial series, when compared against molecular simulation data. For n ≥ 9, both the approximants and the 8-term virial series give an accurate description of the fluid behavior, when compared with simulation data. When taking the limit as n → ∞, an equation of state for hard spheres is obtained, which is closer to simulation data than the 10-term virial series for hard spheres, and is comparable in accuracy to other recently proposed equations of state. By applying a least square fit to the approximants, we obtain a general and accurate soft-sphere equation of state as a function of n, valid over the full range of density in the fluid phase.
Donovan, David Patrick; Quante, Markus; Schlimme, Ingo; Macke, Andreas
2004-09-01
The effect of ice crystal size and shape on the relation between radar reflectivity and optical extinction is examined. Discrete-dipole approximation calculations of 95-GHz radar reflectivity and ray-tracing calculations are applied to ice crystals of various habits and sizes. Ray tracing was used primarily to calculate optical extinction and to provide approximate information on the lidar backscatter cross section. The results of the combined calculations are compared with Mie calculations applied to collections of different types of equivalent spheres. Various equivalent sphere formulations are considered, including equivalent radar-lidar spheres; equivalent maximum dimension spheres; equivalent area spheres, and equivalent volume and equivalent effective radius spheres. Marked differences are found with respect to the accuracy of different formulations, and certain types of equivalent spheres can be used for useful prediction of both the radar reflectivity at 95 GHz and the optical extinction (but not lidar backscatter cross section) over a wide range of particle sizes. The implications of these results on combined lidar-radar ice cloud remote sensing are discussed.
NASA Astrophysics Data System (ADS)
Sitek, M.; Pojmański, G.
2014-06-01
This paper presents the results of our extensive search for the bright variable stars in approximately 30 000 square degrees of the south sky in the I-band data collected by 9o×9o camera of the All Sky Automated Survey between 2002 and 2009. Lists of over 27 000 variable stars brighter than 9 mag at maximum light, with amplitudes ranging from 0.02 mag to 7 mag and variability time-scales from hours to years, as well as corresponding light curves are provided. Automated classification algorithm based on stellar properties (period, Fourier coefficients, 2MASS J, H, K, colors, ASAS V-band data) was used to roughly classify objects. Despite low spatial resolution of the ASAS data (≍15'') we cross-identified all objects with other available data sources. Coordinates of the most probable 2MASS counterparts are provided. 27 705 stars brighter than I=9 mag were found to be variable, of which 7842 objects were detected to be variable for the first time. Brief statistics and discussion of the presented data is provided. All the photometric data is available over the Internet at http://www.astrouw.edu.pl/ gp/asas/AsasBrightI.html
Inhomogeneous fluid of penetrable-spheres: Application of the random phase approximation
NASA Astrophysics Data System (ADS)
Xiang, Yan; Frydel, Derek
2017-05-01
The focus of the present work is the application of the random phase approximation (RPA), derived for inhomogeneous fluids [Frydel and Ma, Phys. Rev. E 93, 062112 (2016)], to penetrable-spheres. As penetrable-spheres transform into hard-spheres with increasing interactions, they provide an interesting case for exploring the RPA, its shortcomings, and limitations, the weak- versus the strong-coupling limit. Two scenarios taken up by the present study are a one-component and a two-component fluid with symmetric interactions. In the latter case, the mean-field contributions cancel out and any contributions from particle interactions are accounted for by correlations. The accuracy of the RPA for this case is the result of a somewhat lucky cancellation of errors.
Structure and effective interactions in three-component hard sphere liquids.
König, A; Ashcroft, N W
2001-04-01
Complete and simple analytical expressions for the partial structure factors of the ternary hard sphere mixture are obtained within the Percus-Yevick approximation and presented as functions of relative packing fractions and relative hard sphere diameters. These solutions follow from the Laplace transform method as applied to multicomponent systems by Lebowitz [Phys. Rev. 133, A895 (1964)]. As an important application, we examine effective interactions in hard sphere liquid mixtures using the microscopic information contained in their partial structure factors. Thus the ensuring pair potential for an effective one-component system is obtained from the correlation functions by using an approximate inversion, and examples of effective potentials for three-component hard sphere mixtures are given. These mixtures may be of particular interest for the study of the packing aspects of melts that form glasses or quasicrystals, since noncrystalline solids often emerge from melts with at least three atomic constituents.
Effects of Mesalamine Treatment on Gut Barrier Integrity After Burn Injury.
Cannon, Abigail R; Akhtar, Suhail; Hammer, Adam M; Morris, Niya L; Javorski, Michael J; Li, Xiaoling; Kennedy, Richard H; Gamelli, Richard L; Choudhry, Mashkoor A
2016-01-01
Gut barrier disruption is often implicated in pathogenesis associated with burn and other traumatic injuries. In this study, the authors examined whether therapeutic intervention with mesalamine (5-aminosalicylic acid [5-ASA]), a common anti-inflammatory treatment for patients with inflammatory bowel disease, reduces intestinal inflammation and maintains normal barrier integrity after burn injury. Male C57BL/6 mice were administered an approximately 20% TBSA dorsal scald burn and resuscitated with either 1 ml normal saline or 100 mg/kg of 5-ASA dissolved in saline. The authors examined intestinal transit and permeability along with the levels of small intestine epithelial cell proinflammatory cytokines and tight junction protein expression 1 day after burn injury in the presence or absence of 5-ASA. A significant decrease in intestinal transit was observed 1 day after burn injury, which accompanied a significant increase in gut permeability. The authors found a substantial increase in the levels of interleukin (IL)-6 (by ~1.5-fold) and IL-18 (by ~2.5-fold) in the small intestine epithelial cells 1 day after injury. Furthermore, burn injury decreases the expression of the tight junction proteins claudin-4, claudin-8, and occludin. Treatment with 5-ASA after burn injury prevented the burn-induced increase in permeability, partially restored normal intestinal transit, normalized the levels of the proinflammatory cytokines IL-6 and IL-18, and restored tight junction protein expression of claudin-4 and occludin compared with that of sham levels. Together these findings suggest that 5-ASA can potentially be used as treatment to decrease intestinal inflammation and normalize intestinal function after burn injury.
Brzozowski, T; Konturek, P C; Konturek, S J; Ernst, H; Stachura, J; Hahn, E G
1995-01-01
Gastric adaptation to injury during repeated doses of acetyl salicylic acid (ASA) is a well documented finding but it is not known whether this adaptation affects the tolerance of the mucosa to other strong irritants. Gastric adaptation was induced by repeated daily doses of acidified ASA (100 mg/kg in 1.5 ml of 0.2 N HCl) given intragastrically (series A rats). Control rats with an intact stomach were given daily intragastric vehicle only (1.5 ml of 0.2 N HCl) (series B). After full adaptation to ASA (5 days), rats were challenged again with acidified ASA or, for comparison, with strong irritants such as 100% ethanol, 200 mM acidified taurocholate, or 25% NaCl for 1 hour or with water immersion and restraint for 3.5 hours. The first dose of ASA produced numerous gastric lesions and deep histological necrosis accompanied by a fall in the gastric blood flow, negligible expression of epidermal growth factor (EGF) and transforming growth factor alpha (TGF alpha) or their receptors, and no evidence of mucosal proliferation. As adaptation to ASA developed, however, the areas of gastric lesions were reduced by more than 80% and there was a noticeable decrease in deep necrosis, a partial restoration of gastric blood flow, an approximately four-fold increase in EGF expression (but not in TGF alpha) and its receptors, and an appreciable increase in mucosal cell proliferation compared with vehicle treated rats. Increases in the mucosal expression of EGF receptors and the luminal content of EGF were also found in ASA adapted animals. In ASA adapted rats subsequently challenged with 100% ethanol, 200 mM TC, 25% NaCl, or stress, the area of the gastric lesions and deep histological necrosis were appreciably reduced compared with values in vehicle treated rats. This increased mucosal tolerance to strong irritants was also accompanied by the return of the gastric blood flow towards control levels and further significant increases in the mucosal expression of EGF receptors and mucosal cell proliferation. Gastric adaptation to ASA enhances the mucosal resistance to injury by strong irritants probably as a result of the restoration of the gastric blood flow and increased cell proliferation that may result from increased mucosal expression of EGF and its receptors. Images Figure 1 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:8537043
Can the Equivalent Sphere Model Approximate Organ Doses in Space Radiation Environments?
NASA Technical Reports Server (NTRS)
Zi-Wei, Lin
2007-01-01
In space radiation calculations it is often useful to calculate the dose or dose equivalent in blood-forming organs (BFO). the skin or the eye. It has been customary to use a 5cm equivalent sphere to approximate the BFO dose. However previous studies have shown that a 5cm sphere gives conservative dose values for BFO. In this study we use a deterministic radiation transport with the Computerized Anatomical Man model to investigate whether the equivalent sphere model can approximate organ doses in space radiation environments. We find that for galactic cosmic rays environments the equivalent sphere model with an organ-specific constant radius parameter works well for the BFO dose equivalent and marginally well for the BFO dose and the dose equivalent of the eye or the skin. For solar particle events the radius parameters for the organ dose equivalent increase with the shielding thickness, and the model works marginally for BFO but is unacceptable for the eye or the skin The ranges of the radius parameters are also shown and the BFO radius parameters are found to be significantly larger than 5 cm in all eases.
Absorption and scattering by fractal aggregates and by their equivalent coated spheres
NASA Astrophysics Data System (ADS)
Kandilian, Razmig; Heng, Ri-Liang; Pilon, Laurent
2015-01-01
This paper demonstrates that the absorption and scattering cross-sections and the asymmetry factor of randomly oriented fractal aggregates of spherical monomers can be rapidly estimated as those of coated spheres with equivalent volume and average projected area. This was established for fractal aggregates with fractal dimension ranging from 2.0 to 3.0 and composed of up to 1000 monodisperse or polydisperse monomers with a wide range of size parameter and relative complex index of refraction. This equivalent coated sphere approximation was able to capture the effects of both multiple scattering and shading among constituent monomers on the integral radiation characteristics of the aggregates. It was shown to be superior to the Rayleigh-Debye-Gans approximation and to the equivalent coated sphere approximation proposed by Latimer. However, the scattering matrix element ratios of equivalent coated spheres featured large angular oscillations caused by internal reflection in the coating which were not observed in those of the corresponding fractal aggregates. Finally, the scattering phase function and the scattering matrix elements of aggregates with large monomer size parameter were found to have unique features that could be used in remote sensing applications.
Can the Equivalent Sphere Model Approximate Organ Doses in Space?
NASA Technical Reports Server (NTRS)
Lin, Zi-Wei
2007-01-01
For space radiation protection it is often useful to calculate dose or dose,equivalent in blood forming organs (BFO). It has been customary to use a 5cm equivalent sphere to. simulate the BFO dose. However, many previous studies have concluded that a 5cm sphere gives very different dose values from the exact BFO values. One study [1] . concludes that a 9 cm sphere is a reasonable approximation for BFO'doses in solar particle event environments. In this study we use a deterministic radiation transport [2] to investigate the reason behind these observations and to extend earlier studies. We take different space radiation environments, including seven galactic cosmic ray environments and six large solar particle events, and calculate the dose and dose equivalent in the skin, eyes and BFO using their thickness distribution functions from the CAM (Computerized Anatomical Man) model [3] The organ doses have been evaluated with a water or aluminum shielding of an areal density from 0 to 20 g/sq cm. We then compare with results from the equivalent sphere model and determine in which cases and at what radius parameters the equivalent sphere model is a reasonable approximation. Furthermore, we address why the equivalent sphere model is not a good approximation in some cases. For solar particle events, we find that the radius parameters for the organ dose equivalent increase significantly with the shielding thickness, and the model works marginally for BFO but is unacceptable for the eye or the skin. For galactic cosmic rays environments, the equivalent sphere model with an organ-specific constant radius parameter works well for the BFO dose equivalent, marginally well for the BFO dose and the dose equivalent of the eye or the skin, but is unacceptable for the dose of the eye or the skin. The ranges of the radius parameters are also being investigated, and the BFO radius parameters are found to be significantly, larger than 5 cm in all cases, consistent with the conclusion of an earlier study [I]. The radius parameters for the dose equivalent in GCR environments are approximately between 10 and I I cm for the BFO, 3.7 to 4.8 cm for the eye, and 3.5 to 5.6 cm for the skin; while the radius parameters are between 10 and 13 cm for the BFO dose.
Cutting-edge issues in autoimmune orchitis.
Silva, Clovis A; Cocuzza, Marcello; Borba, Eduardo F; Bonfá, Eloísa
2012-04-01
Autoimmune orchitis is a relevant cause of decreased fecundity in males, and it is defined as a direct aggression to the testis with the concomitant presence of anti-sperm antibodies (ASA). The presence of these specific antibodies has been observed in approximately 5-12% of infertile male partners. Primary autoimmune orchitis is defined by isolated infertility with ASA but without evidence of a systemic disease. Secondary causes of orchitis and/or testicular vasculitis are uniformly associated with autoimmune diseases, mainly in primary vasculitis such as polyarteritis nodosa, Behçet's disease, and Henoch-Schönlein purpura. The overall frequencies of acute orchitis and ASA in rheumatic diseases are 2-31% and 0-50%, respectively. The pathogenesis of primary/secondary autoimmune orchitis is not completely understood but probably involves the access of immune cells to the testicular microenvironment due to inflammation, infection or trauma, leading to apoptosis of spermatocytes and spermatids. Glucocorticoids and immunosuppressive drugs are indicated in autoimmune orchitis-associated active systemic autoimmune diseases. However, there are no standardized treatment options, and the real significance of ASA in infertile men is still controversial. Assisted reproductive technologies such as intrauterine insemination, in vitro fertilization, and intracytoplasmic sperm injection (ICSI) are therapeutic options for male infertility associated with these autoantibodies. ICSI is considered to be the best choice for patients with severe sperm autoimmunity, particularly in males with low semen counts or motility.
Local thermodynamic mapping for effective liquid density-functional theory
NASA Technical Reports Server (NTRS)
Kyrlidis, Agathagelos; Brown, Robert A.
1992-01-01
The structural-mapping approximation introduced by Lutsko and Baus (1990) in the generalized effective-liquid approximation is extended to include a local thermodynamic mapping based on a spatially dependent effective density for approximating the solid phase in terms of the uniform liquid. This latter approximation, called the local generalized effective-liquid approximation (LGELA) yields excellent predictions for the free energy of hard-sphere solids and for the conditions of coexistence of a hard-sphere fcc solid with a liquid. Moreover, the predicted free energy remains single valued for calculations with more loosely packed crystalline structures, such as the diamond lattice. The spatial dependence of the weighted density makes the LGELA useful in the study of inhomogeneous solids.
Han, B H; Suh, D Y; Yang, H O; Park, Y H; Kang, Y H; Kim, Y C
1994-10-01
A new compound, aspalatone (acetylsalicylic acid maltol ester), was synthesized by esterification of acetylsalicylic acid (ASA) and maltol, an antioxidant, and studied for its bleeding time prolongation effect in rats, for its antiplatelet aggregation activity in vitro and ex vivo in rats, and for its antithrombotic activity in vivo using the mouse thromboembolism test. Aspalatone treatment (15 mg/kg p.o.) for 10 days prolonged bleeding time by 57% (p < 0.005) in Sprague-Dawley rats vs control, while ASA treatment (15 mg/kg p.o.) prolonged by 44%. At the low dose of 15 mg/kg p.o. at least 8 days of treatment were necessary for aspalatone and ASA to prolong the bleeding time significantly. On the other hand, salicylic acid maltol ester which lacks the acetyl group did not significantly affect bleeding time at a dose of 15 mg/kg. Aspalatone produced a potent inhibition of collagen-induced platelet aggregation in vitro with IC50 of 1.8 x 10(-4) mol/l, but, similar to ASA, did not significantly inhibit ADP-induced aggregation. The ability of oral aspalatone to inhibit platelet aggregation in rats ex vivo was compared with other reference antiplatelet drugs. Relative potency was ASA > dipyridamole approximately equal to aspalatone > ticlopidine. A single dose of aspalatone potently prevented death due to collagen-induced platelet aggregation in mice in vivo with ED50 value of 32 mg/kg p.o., but failed to prevent death due to ADP-induced platelet aggregation. When given for 10 days, aspalatone prevented collagen-induced death by 90% (p < 0.001) at 20 mg/kg, and this antithrombotic effect lasted after 4 days of wash-out period.(ABSTRACT TRUNCATED AT 250 WORDS)
Pushing the glass transition towards random close packing using self-propelled hard spheres
NASA Astrophysics Data System (ADS)
Ni, Ran; Stuart, Martien A. Cohen; Dijkstra, Marjolein
2013-10-01
Although the concept of random close packing with an almost universal packing fraction of approximately 0.64 for hard spheres was introduced more than half a century ago, there are still ongoing debates. The main difficulty in searching the densest packing is that states with packing fractions beyond the glass transition at approximately 0.58 are inherently non-equilibrium systems, where the dynamics slows down with a structural relaxation time diverging with density; hence, the random close packing is inaccessible. Here we perform simulations of self-propelled hard spheres, and we find that with increasing activity the relaxation dynamics can be sped up by orders of magnitude. The glass transition shifts to higher packing fractions upon increasing the activity, allowing the study of sphere packings with fluid-like dynamics at packing fractions close to RCP. Our study opens new possibilities of investigating dense packings and the glass transition in systems of hard particles.
NASA Astrophysics Data System (ADS)
Kalyuzhnyi, Yurij V.; Cummings, Peter T.
2006-03-01
The Blum-Høye [J. Stat. Phys. 19 317 (1978)] solution of the mean spherical approximation for a multicomponent multi-Yukawa hard-sphere fluid is extended to a polydisperse multi-Yukawa hard-sphere fluid. Our extension is based on the application of the orthogonal polynomial expansion method of Lado [Phys. Rev. E 54, 4411 (1996)]. Closed form analytical expressions for the structural and thermodynamic properties of the model are presented. They are given in terms of the parameters that follow directly from the solution. By way of illustration the method of solution is applied to describe the thermodynamic properties of the one- and two-Yukawa versions of the model.
Bounds on the conductivity of a suspension of random impenetrable spheres
NASA Astrophysics Data System (ADS)
Beasley, J. D.; Torquato, S.
1986-11-01
We compare the general Beran bounds on the effective electrical conductivity of a two-phase composite to the bounds derived by Torquato for the specific model of spheres distributed throughout a matrix phase. For the case of impenetrable spheres, these bounds are shown to be identical and to depend on the microstructure through the sphere volume fraction φ2 and a three-point parameter ζ2, which is an integral over a three-point correlation function. We evaluate ζ2 exactly through third order in φ2 for distributions of impenetrable spheres. This expansion is compared to the analogous results of Felderhof and of Torquato and Lado, all of whom employed the superposition approximation for the three-particle distribution function involved in ζ2. The results indicate that the exact ζ2 will be greater than the value calculated under the superposition approximation. For reasons of mathematical analogy, the results obtained here apply as well to the determination of the thermal conductivity, dielectric constant, and magnetic permeability of composite media and the diffusion coefficient of porous media.
Dunlap, Tareisha; Abdul-Hay, Samer; Chandrasena, R. Esala P.; Hagos, Ghenet K; Sinha, Vaishali; Wang, Zhiqiang; Wang, Huali; Thatcher, Gregory R. J.
2008-01-01
Properties of the NO-ASA family of NO-donating NSAIDs (NO-NSAIDs), notably NCX 4016 (mNO-ASA) and NCX 4040 (pNO-ASA), reported in more than a hundred publications, have included positive preclinical data in cancer chemoprevention and therapy. Evidence is presented that the antiproliferative, the chemopreventive (antioxidant/electrophile response element (ARE) activation), and the anti-inflammatory activity of NO-ASA in cell cultures is replicated by X-ASA derivatives that are incapable of acting as NO donors. pBr-ASA and mBr-ASA are conisogenic with NO-ASA, but are not NO donors. The biological activity of pNO-ASA is replicated by pBr-ASA; and both pNO-ASA and pBr-ASA are bioactivated to the same quinone methide electrophile. The biological activity of mNO-ASA is replicated by mBr-ASA; mNO-ASA and mBr-ASA are bioactivated to different benzyl electrophiles. The observed activity is likely initiated by trapping of thiol biomolecules by the quinone and benzyl electrophiles, leading to depletion of GSH and modification of Cys-containing sensor proteins. Whereas all NO-NSAIDs containing the same structural “linker” as NCX 4040 and NCX 4016 are anticipated to possess activity resulting from bioactivation to electrophilic metabolites, this expectation does not extend to other linker structures. Nitrates require metabolic bioactivation to liberate NO bioactivity, which is often poorly replicated in vitro, and NO bioactivity provided by NO-NSAIDs in vivo provides proven therapeutic benefits in mitigation of NSAID gastrotoxicity. The in vivo properties of X-ASA drugs await discovery. PMID:18485921
Dunlap, Tareisha; Abdul-Hay, Samer O; Chandrasena, R Esala P; Hagos, Ghenet K; Sinha, Vaishali; Wang, Zhiqiang; Wang, Huali; Thatcher, Gregory R J
2008-09-01
Properties of the NO-ASA family of NO-donating NSAIDs (NO-NSAIDs), notably NCX 4016 (mNO-ASA) and NCX 4040 (pNO-ASA), reported in more than one hundred publications, have included positive preclinical data in cancer chemoprevention and therapy. Evidence is presented that the antiproliferative, the chemopreventive (antioxidant/electrophile response element (ARE) activation), and the anti-inflammatory activity of NO-ASA in cell cultures is replicated by X-ASA derivatives that are incapable of acting as NO donors. pBr-ASA and mBr-ASA are conisogenic with NO-ASA, but are not NO donors. The biological activity of pNO-ASA is replicated by pBr-ASA; and both pNO-ASA and pBr-ASA are bioactivated to the same quinone methide electrophile. The biological activity of mNO-ASA is replicated by mBr-ASA; mNO-ASA and mBr-ASA are bioactivated to different benzyl electrophiles. The observed activity is likely initiated by trapping of thiol biomolecules by the quinone and benzyl electrophiles, leading to depletion of GSH and modification of Cys-containing sensor proteins. Whereas all NO-NSAIDs containing the same structural "linker" as NCX 4040 and NCX 4016 are anticipated to possess activity resulting from bioactivation to electrophilic metabolites, this expectation does not extend to other linker structures. Nitrates require metabolic bioactivation to liberate NO bioactivity, which is often poorly replicated in vitro, and NO bioactivity provided by NO-NSAIDs in vivo provides proven therapeutic benefits in mitigation of NSAID gastrotoxicity. The in vivo properties of X-ASA drugs await discovery.
Asiago spectroscopic classification of ASAS-SN18ck, ASAS-SN18cp, ASAS-SN18cq and ASASSN-18cj
NASA Astrophysics Data System (ADS)
Tomasella, L.; Benetti, S.; Cappellaro, E.; Turatto, M.
2018-02-01
The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classification of ASAS-SN18ck, ASAS-SN18cp, ASAS-SN18cq and ASASSN-18cj, discovered during the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014, Atel #11178).
Aspirin Allergy Desensitization in Cerebrovascular Disease
Zuckerman, Scott L; Seder, David B; Tsujiura, Crystiana; Cushing, Deborah; Gallup, Holly; Mocco, J; Hanel, Richard A; Ecker, Robert D
2014-01-01
Summary Aspirin (ASA) is the mainstay of treatment in cerebrovascular and systemic vascular disease. ASA hypersensitivity can pose a challenge to achieving optimum medical management prior to and after neurointerventional treatment. Desensitization to ASA is well described in the allergy and cardiovascular literature, but there are no similar discussions specific to neurointervention. The purpose of our study was to describe our experience with ASA hypersensitivity management and review the relevant literature. Two cases of patients with symptomatic cerebrovascular disease requiring neurointervention who were successfully desensitized to their ASA hypersensitivity prior to treatment are described. The subsequent literature is reviewed. Several ASA desensitization protocols exist and have been proven to successfully treat ASA hypersensitivity and allow for ASA therapy to be safely initiated. We describe several previously published protocols. ASA desensitization is a safe and simple way to manage ASA hypersensitivity. We provide comprehensive management guidelines for the neurointerventionalist engaging in ASA desensitization. PMID:24556294
Effective transport properties of composites of spheres
NASA Astrophysics Data System (ADS)
Felderhof, B. U.
1994-06-01
The effective linear transport properties of composites of spheres may be studied by the methods of statistical physics. The analysis leads to an exact cluster expansion. The resulting expression for the transport coefficients may be evaluated approximately as the sum of a mean field contribution and correction terms, given by cluster integrals over two-sphere and three-sphere correlation functions. Calculations of this nature have been performed for the effective dielectric constant, as well as the effective elastic constants of composites of spheres. Accurate numerical data for the effective properties may be obtained by computer simulation. An efficient formulation uses multiple expansion in Cartesian coordinates and periodic boundary conditions. Extensive numerical results have been obtained for the effective dielectric constant of a suspension of randomly distributed spheres.
Inhibitory activity of aspirin on von Willebrand factor-induced platelet aggregation.
Homoncik, M; Jilma, B; Eichelberger, B; Panzer, S
2000-09-01
The effect of aspirin (ASA) on vWF induced platelet - platelet interaction is unknown. We therefore tested the response of platelets to von Willebrand factor (vWF) coated beads induced platelet aggregation before and after i.v. and oral ASA. 1000 mg ASA was infused to 10 healthy individuals and after a wash-out period 7 volunteers received 100 mg ASA orally over a period of 11 days. Prior to ASA and in regular intervals thereafter we tested the reactivity to vWF-coated beads to assess platelet adhesion/aggregation and the fade-out time of ASA effects on platelets. Considerable interindividual variability in response to vWF-coated beads was observed, both before ASA and after treatment with ASA. The maximal response to vWF-coated beads (Tmax), the time lag, and the slope of the curve were significantly affected by i.v. ASA, whereas 100 mg of ASA had only inconstant effect on Tmax and slope. The absolute reduction of Tmax after ASA depended on the pre-ASA level, while the percentage of the reduction was similar in all individuals. Thus, platelet aggregation induced by vWF-coated beads is impaired by ASA. Furthermore, our data indicate a large interindividual variability of the response to ASA shortly after treatment induction, which becomes more constant after prolonged treatment.
Long-distance transport of L-ascorbic acid in potato
Tedone, Luigi; Hancock, Robert D; Alberino, Salvatore; Haupt, Sophie; Viola, Roberto
2004-01-01
Background Following on from recent advances in plant AsA biosynthesis there is increasing interest in elucidating the factors contributing to the L-ascorbic acid (AsA) content of edible crops. One main objective is to establish whether in sink organs such as fruits and tubers, AsA is synthesised in situ from imported photoassimilates or synthesised in source tissues and translocated via the phloem. In the current work we test the hypothesis that long-distance transport is involved in AsA accumulation within the potato tuber, the most significant source of AsA in the European diet. Results Using the EDTA exudation technique we confirm the presence of AsA in the phloem of potato plants and demonstrate a correlation between changes in the AsA content of source leaves and that of phloem exudates. Comparison of carboxyflourescein and AgNO3 staining is suggestive of symplastic unloading of AsA in developing tubers. This hypothesis was further supported by the changes in AsA distribution during tuber development which closely resembled those of imported photoassimilates. Manipulation of leaf AsA content by supply of precursors to source leaves resulted in increased AsA content of developing tubers. Conclusion Our data provide strong support to the hypothesis that long-distance transport of AsA occurs in potato. We also show that phloem AsA content and AsA accumulation in sink organs can be directly increased via manipulation of AsA content in the foliage. We are now attempting to establish the quantitative contribution of imported AsA to overall AsA accumulation in developing potato tubers via transgenic approaches. PMID:15377389
NASA Astrophysics Data System (ADS)
Kandilian, Razmig; Pruvost, Jérémy; Artu, Arnaud; Lemasson, Camille; Legrand, Jack; Pilon, Laurent
2016-05-01
This paper aims to experimentally and directly validate a recent theoretical method for predicting the radiation characteristics of photosynthetic microorganisms. Such predictions would facilitate light transfer analysis in photobioreactors (PBRs) to control their operation and to maximize their production of biofuel and other high-value products. The state of the art experimental method can be applied to microorganisms of any shape and inherently accounts for their non-spherical and heterogeneous nature. On the other hand, the theoretical method treats the microorganisms as polydisperse homogeneous spheres with some effective optical properties. The absorption index is expressed as the weighted sum of the pigment mass absorption cross-sections and the refractive index is estimated based on the subtractive Kramers-Kronig relationship given an anchor refractive index and wavelength. Here, particular attention was paid to green microalgae Chlamydomonas reinhardtii grown under nitrogen-replete and nitrogen-limited conditions and to Chlorella vulgaris grown under nitrogen-replete conditions. First, relatively good agreement was found between the two methods for determining the mass absorption and scattering cross-sections and the asymmetry factor of both nitrogen-replete and nitrogen-limited C. reinhardtii with the proper anchor point. However, the homogeneous sphere approximation significantly overestimated the absorption cross-section of C. vulgaris cells. The latter were instead modeled as polydisperse coated spheres consisting of an absorbing core containing pigments and a non-absorbing but strongly refracting wall made of sporopollenin. The coated sphere approximation gave good predictions of the experimentally measured integral radiation characteristics of C. vulgaris. In both cases, the homogeneous and coated sphere approximations predicted resonance in the scattering phase function that were not observed experimentally. However, these approximations were sufficiently accurate to predict the fluence rate and local rate of photon absorption in PBRs.
Smetanová, Libuše; Stětinová, Věra; Kholová, Dagmar; Kuneš, Martin; Nobilis, Milan; Svoboda, Zbyněk; Květina, Jaroslav
2013-09-01
The aim of the study was 1) to estimate permeability of 5-aminosalicylic acid (5-ASA), 2) to categorize 5-ASA according to BCS (Biopharmaceutics Classification System), and 3) to contribute to determination of 5-ASA transintestinal transport and biotransformation mechanisms. The in situ rat intestine perfusion was used as an initial method to study 5-ASA transport. The amount of 5-ASA (released from tablet) transferred into portal circulation reached 5.79 ± 0.24%. During this transport, the intestinal formation of 5-ASA main metabolite (N-ac-5-ASA) occurred. N-ac-5-ASA was found in perfusate both from intestinal lumen and from v. portae. In in vitro Caco-2 monolayers, transport of 5-ASA (10-1000 µmol/l) was studied in apical-basolateral and basolateral-apical direction (iso-pH 7.4 conditions). The transport of total 5-ASA (parent drug plus intracellularly formed N-ac-5-ASA) was linear with time, concentration- and direction-dependent. Higher basolateral-apical (secretory) transport was mainly caused by higher transport of the metabolite (suggesting metabolite efflux transport). Transport of 5-ASA (only parent drug) was saturable (transepithelial carrier-mediated) at low doses, dominated by passive, paracellular process in higher doses which was confirmed by increased 5-ASA transport using Ca2+-free transport medium. The estimated low 5-ASA permeability and its low solubility enable to classify 5-ASA as BCS class IV.
Zuckerman, Scott L; Seder, David B; Tsujiura, Crystiana; Cushing, Deborah; Gallup, Holly; Mocco, J; Hanel, Richard A; Ecker, Robert D
2014-01-01
Aspirin (ASA) is the mainstay of treatment in cerebrovascular and systemic vascular disease. ASA hypersensitivity can pose a challenge to achieving optimum medical management prior to and after neurointerventional treatment. Desensitization to ASA is well described in the allergy and cardiovascular literature, but there are no similar discussions specific to neurointervention. The purpose of our study was to describe our experience with ASA hypersensitivity management and review the relevant literature. Two cases of patients with symptomatic cerebrovascular disease requiring neurointervention who were successfully desensitized to their ASA hypersensitivity prior to treatment are described. The subsequent literature is reviewed. Several ASA desensitization protocols exist and have been proven to successfully treat ASA hypersensitivity and allow for ASA therapy to be safely initiated. We describe several previously published protocols. ASA desensitization is a safe and simple way to manage ASA hypersensitivity. We provide comprehensive management guidelines for the neurointerventionalist engaging in ASA desensitization.
Radial distribution function for hard spheres in fractal dimensions: A heuristic approximation.
Santos, Andrés; de Haro, Mariano López
2016-06-01
Analytic approximations for the radial distribution function, the structure factor, and the equation of state of hard-core fluids in fractal dimension d (1≤d≤3) are developed as heuristic interpolations from the knowledge of the exact and Percus-Yevick results for the hard-rod and hard-sphere fluids, respectively. In order to assess their value, such approximate results are compared with those of recent Monte Carlo simulations and numerical solutions of the Percus-Yevick equation for a fractal dimension [M. Heinen et al., Phys. Rev. Lett. 115, 097801 (2015)PRLTAO0031-900710.1103/PhysRevLett.115.097801], a good agreement being observed.
Hu, Qingsong; Liu, Yuling; Gu, Xueyuan; Zhao, Yaping
2017-08-01
Arsenic pollution poses severe threat to human health, therefore dealing with the problem of arsenic contamination in water bodies is extremely important. The adsorption behaviors of different arsenic species, such as arsenate (As(V)), p-arsanilic acid (p-ASA), roxarsone (ROX), dimethylarsenate (DMA) from water using mesoporous bimetal oxide magnetic manganese ferrite nanoparticles (MnFe 2 O 4 ) have been detailedly investigated. The adsorbent was synthesized via a facile co-precipitation approach and recovered conveniently owing to its strong magnetic properties. The obtained MnFe 2 O 4 with large surface area and abundant hydroxyly functional groups exhibited excellent adsorption performance for As(V) and p-ASA, in contrast to ROX and DMA with the maximum adsorption capacities of As(V), p-ASA, ROX and DMA of 68.25 mg g -1 , 59.45 mg g -1 , 51.49 mg g -1 , and 35.77 mg g -1 , respectively. The Langmuir model and the pseudo-second-order kinetic model correlated satisfactorily with the adsorption thermodynamics and kinetics, and thermodynamic parameters depicted the spontaneous endothermic nature for the adsorption of different arsenic species. The adsorption mechanism of different arsenic species onto MnFe 2 O 4 nanoparticles at various pH values could be explained by surface complexation and molecular structural variations. Attenuated Total internal Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) further proved that arsenic species were bonded to the surface of MnFe 2 O 4 through the formation of an inner-sphere complex between the arsenic acid moiety and surface metal centers. The results would help to know the interaction of arsenic species with iron-manganese minerals and the mobility of arsenic species in natural environments. Copyright © 2017 Elsevier Ltd. All rights reserved.
Goren, Amir; Liu, Xianchen; Gupta, Shaloo; Simon, Teresa A; Phatak, Hemant
2015-01-01
Vitamin K antagonist (VKA) and aspirin (ASA) are recommended for stroke prevention in patients with atrial fibrillation (AF). This study examined VKA and ASA use and their clinical correlates, including CHADS2 stroke risk scores, among adult patients with AF in the general population. Participants included 1290 (1.72%) adults reporting diagnosis with AF (mean age, 64.9 years; 65% men) from the 2009 US National Health and Wellness Survey, an online, self-administered, nationwide, stratified random sample survey of 75,000 adults. Antithrombotic use patterns, including VKA, ASA, VKA+ASA, and non-VKA/ASA, and their correlates were examined using logistic regressions. Respondents with AF were treated with VKA (26.6%), ASA (34.5%), VKA+ASA (15.4%), or neither (23.5%). Among those with CHADS2 ≥1, 19.3% did not report use of VKA or ASA. Among those with CHADS2 ≥2, 35.7% were treated only with ASA. Adjusting for covariates in logistic regressions, CHADS2 ≥1 was associated with VKA and/or ASA (vs. non-VKA/ASA) use (P ≤ 0.02), but CHADS2 score did not differentiate VKA versus ASA use (P > 0.4). Comorbidities were associated with ASA versus VKA use (P ≤ 0.01). Older age, male gender, married status, and obesity were each associated with use of at least one of the treatments investigated (all P < 0.05). One-in-five AF patients with CHADS2 ≥1 were untreated and more than one-third with CHADS2 ≥2 treated with only ASA for stroke prevention. Our findings suggest that although patient characteristics including CHADS2 score were associated with either VKA or ASA use, CHADS2 score was unrelated to VKA versus ASA treatment.
Menke, H; John, K D; Klein, A; Lorenz, W; Junginger, T
1992-12-01
The value of ASA classification in assessment of perioperative risk, i.e. especially postoperative morbidity, was analyzed prospectively using the data of 2937 patients. The analysis took into account the criteria validity, reliability, and sensitivity. The incidence of post-operative morbidity after elective surgery rose from 3.9% in ASA class I to 36% in ASA class IV. Mortality was 0.6% in ASA class II, whereas 9.3% died in ASA class IV. Morbidity, mortality respectively, after emergency surgery was 10.2% in ASA class II compared to 69% in class IV, mortality 1.4% compared to 21.5%. Differences between the ASA classes were confirmed (p-value < 0.05) considering separate kinds of complications and different periods. Furthermore, ASA classification was a valuable reference to length of stay and severity of necessary therapy at the ICU.
Pallanca, Jane E.; Smirnoff, Nicholas
1999-01-01
l-Ascorbic acid (AsA) accumulates in pea (Pisum sativum L.) seedlings during germination, with the most rapid phase of accumulation coinciding with radicle emergence. Monodehydroascorbate reductase and dehydroascorbic acid reductase were active in the embryonic axes before AsA accumulation started, whereas AsA oxidase and AsA peroxidase activities increased in parallel with AsA. Excised embryonic axes were used to investigate the osone pathway of AsA biosynthesis, in which d-glucosone and l-sorbosone are the proposed intermediates. [U-14C]Glucosone was incorporated into AsA and inhibited the incorporation of [U-14C]glucose (Glc) into AsA. A higher d-glucosone concentration (5 mm) inhibited AsA accumulation. l-Sorbosone did not affect AsA pool size but caused a small inhibition in the incorporation of [U-14C]Glc into AsA. Oxidase and dehydrogenase activities capable of converting Glc or Glc-6-phosphate to glucosone were not detected in embryonic axis extracts. The osones are therefore unlikely to be physiological intermediates of AsA biosynthesis. l-Galactono-1,4-lactone, recently proposed as the AsA precursor (G.L. Wheeler, M.A. Jones, N. Smirnoff [1998] Nature 393: 365–369), was readily converted to AsA by pea embryonic axes. Although l-galactono-1,4-lactone did not inhibit [14C]Glc incorporation into AsA, this does not mean that it is not a precursor, because competition between endogenous and exogenous pools was minimized by its very small pool size and rapid metabolism. PMID:10364396
Viganò, G; Garagiola, U; Gaspari, F
1991-01-01
A single-blind, randomized, crossover pharmacokinetic study was carried out to investigate the bioavailability of a new oral buffered 325 mg acetylsalicylic acid (ASA) formulation (ASPIRINA 03) in comparison with a 325 mg plain tablet. Twelve healthy volunteers of both sexes, aged between 20 and 37 years, received buffered or plain ASA on two separate occasions with a wash-out interval of at least two weeks. ASA and salicylic acid (SA) plasma levels were determined by a chromatographic method. The results showed no difference between the area under concentration time curve (AUC0-infinity) ASA values of both formulations (p = 0.19), and buffered ASA relative bioavailability was 102.49% (= bioequivalence). A significant difference was found between the AUC0-30 min ASA values: 90.5 micrograms. min/ml with buffered and 67.7 micrograms. min/ml with the plain tablet (p less than 0.05). The buffered ASA time of maximum concentration was shorter (28 +/- 8 min) than the plain one (38 +/- 19 min, p less than 0.05). The plasma concentrations and pharmacokinetic parameters of SA were not significantly different after the administration of the two ASA formulations. The plain ASA tablet had a significantly lower (p less than 0.05) dissolution rate than buffered ASA tablet. Moreover, the buffered ASA tablet significantly (p less than 0.01) increased the pH by 0.5 units. In conclusion, the bioavailability of the new oral buffered ASA was equivalent to that of plain ASA, but the plasma concentration peak was reached in a shorter time.
Veselka, Josef; Zemánek, David; Jahnlová, Denisa; Krejčí, Jan; Januška, Jaroslav; Dabrowski, Maciej; Bartel, Thomas; Tomašov, Pavol
2015-10-01
Because the final myocardial scar might be theoretically associated with an increased risk of sudden cardiac death, the long-term clinical course of patients who undergo alcohol septal ablation (ASA) is still a matter of debate. In this retrospective multicentre study, we report outcomes after ASA, including survival, analysis of causes of deaths, and association between time and cause of death. We enrolled 366 consecutive patients (58 ± 12 years, 54% women) who were treated using ASA and followed-up for 5.1 ± 4.5 years. The in-hospital and 30-day mortality were 0.5% and 0.8%, respectively; the ASA-related morbidity was < 20%. Overall, 52 patients died during 1867 patient-years, which means the all-cause mortality rate was 2.8% per year. The mortality rates of sudden death and sudden death with an appropriate implantable cardioverter-defibrillator (ICD) discharge were 0.4% and 1% per year, respectively. Patients with sudden death or appropriate ICD discharge experienced these mortality events at younger age than patients who died of other hypertrophic obstructive cardiomyopathy-related causes (60.8 years [range, 52-71.5 years] vs 72.4 years [range, 64.2-75.2 years]; P = 0.048). A total of 292 patients (80%) had an outflow gradient ≤ 30 mm Hg, and 327 patients (89%) were in New York Heart Association class ≤ II at the last clinical check-up. ASA had low procedure-related mortality, with subsequent 1% occurrence of sudden mortality events per year and 2.8% mortality rate per year in the long-term follow-up. Patients with sudden death or ICD discharge experienced the mortality events approximately 1 decade earlier than patients who died from other causes not related to hypertrophic cardiomyopathy. Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
Aspirin upregulates αB-Crystallin to protect the myocardium against heat stress in broiler chickens
Tang, Shu; Yin, Bin; Song, Erbao; Chen, Hongbo; Cheng, Yanfen; Zhang, Xiaohui; Bao, Endong; Hartung, Joerg
2016-01-01
We established in vivo and in vitro models to investigate the role of αB-Crystallin (CryAB) and assess the ability of aspirin (ASA) to protect the myocardium during prolonged heat stress. Thirty-day-old chickens were divided into three groups (n = 90): heat stress (HS, 40±1 °C); ASA(−)HS(+), 1 mg/kg ASA orally 2 h before heat stress; and ASA(+)HS(−), pretreated with aspirin, no heat stress (25 °C). Hearts were excised after 0, 1, 2, 3, 5, 7, 10, 15 and 24 h. Heat stress increased body temperature, though the ASA(−)HS(+) group had significantly higher temperatures than the ASA(+)HS(+) group at all time points. Compared to ASA(+)HS(+), the ASA(−)HS(+) group displayed increased sensitivity to heat stress. Pathological analysis revealed the ASA (+)HS(+) myocardium showed less severe changes (narrowed, chaotic fibers; fewer necrotic cells) than the ASA(−)HS(+) group (bleeding and extensive cell death). In vitro, ASA-pretreatment significantly increased primary chicken myocardial cell survival during heat stress. ELISAs indicated ASA induced CryAB in vivo to protect against heat stress-induced myocardial damage, but ASA did not induce CryAB in primary chicken myocardial cells. The mechanisms by which ASA induces the expression of CryAB in vivo and protects the myocardium during heat stress merit further research. PMID:27857180
The user interface for all 2016 versions of ASA24, including ASA24-Canada-2016 and ASA24-Australia-2016, employs a responsive design, meaning that these latest versions of the ASA24 system can be used on sm artphones and tablets, in addition to laptops and desktops.
ASA24-2014, 2012, and 2011, all versions (no longer available)
Researchers can no longer register new studies to use ASA24-2014, ASA24-Canada-2014 and ASA24-2011; however, all of these versions of the ASA24® system are available for data collection until March 2017.
Smectic phases in hard particle mixtures: Koda's theory
NASA Astrophysics Data System (ADS)
Vesely, Franz J.
Mixtures of parallel linear particles and spheres tend to demix upon compression. The linear species usually concentrates in regular layers, thus forming a smectic phase. With increasing concentration of spheres this 'smectic demixing' transition occurs at ever lower packing densities. For the specific case of hard spherocylinders and spheres Koda et al. [T. Koda, M. Numajiri, S. Ikeda, J. Phys. Jap., 65, 3551 (1996)] have explained the layering effect in terms of a second virial approximation to the free energy. We extend this approach from spherocylinders to other linear particles, namely fused spheres, ellipsoids and sphero-ellipsoids.
Hollow carbon spheres in microwaves: Bio inspired absorbing coating
NASA Astrophysics Data System (ADS)
Bychanok, D.; Li, S.; Sanchez-Sanchez, A.; Gorokhov, G.; Kuzhir, P.; Ogrin, F. Y.; Pasc, A.; Ballweg, T.; Mandel, K.; Szczurek, A.; Fierro, V.; Celzard, A.
2016-01-01
The electromagnetic response of a heterostructure based on a monolayer of hollow glassy carbon spheres packed in 2D was experimentally surveyed with respect to its response to microwaves, namely, the Ka-band (26-37 GHz) frequency range. Such an ordered monolayer of spheres mimics the well-known "moth-eye"-like coating structures, which are widely used for designing anti-reflective surfaces, and was modelled with the long-wave approximation. Based on the experimental and modelling results, we demonstrate that carbon hollow spheres may be used for building an extremely lightweight, almost perfectly absorbing, coating for Ka-band applications.
Lectures on the scattering of light. [by dielectric sphere
NASA Technical Reports Server (NTRS)
Saxon, D. S.
1974-01-01
The exact (Mie) theory for the scattering of a plane wave by a dielectric sphere is presented. Since this infinite series solution is computationally impractical for large spheres, another formulation is given in terms of an integral equation valid for a bounded, but otherwise general array of scatterers. This equation is applied to the scattering by a single sphere, and several methods are suggested for approximating the scattering cross section in closed form. A tensor scattering matrix is introduced, in terms of which some general scattering theorems are derived. The application of the formalism to multiple scattering is briefly considered.
SCF-Xα-SW electron densities with the overlapping sphere approximation
NASA Astrophysics Data System (ADS)
McMaster, Blair N.; Smith, Vedene H., Jr.; Salahub, Dennis R.
Self consistent field-Xα-scattered wave (SCF-Xα-SW) calculations have been performed for a series of eight first and second row homonuclear diatomic molecules using both the touching (TS) and 25 per cent overlapping sphere (OS) versions. The OS deformation density maps exhibit much better quantitative agreement with those from other Xα methods, which do not employ the spherical muffin-tin (MT) potential approximation, than do the TS maps. The OS version thus compensates very effectively for the errors involved in the MT approximation in computing electron densities. A detailed comparison between the TS- and OS-Xα-SW orbitals reveals that the reasons for this improvement are surprisingly specific. The dominant effect of the OS approximation is to increase substantially the electron density near the midpoint of bonding σ orbitals, with a consequent reduction of the density behind the atoms. A similar effect occurs for the bonding π orbitals but is less pronounced. These effects are due to a change in hybridization of the orbitals, with the OS approximation increasing the proportion of the subdominant partial waves and hence changing the shapes of the orbitals. It is this increased orbital polarization which so effectively compensates for the lack of (non-spherically symmetric) polarization components in the MT potential, when overlapping spheres are used.
2008-03-25
primary point person for this initiative is ASA for Installations and Environment (ASA- I& E ). 9 * There are 11 major commands, only 1 shown on...FM&C) DCS G-8 DCS G-8 ASA (I& E ) ASA (I& E ) ASA (M&RA) ASA (M&RA) DCS G-1 DCS G-1 CIO/ G-6 CIO/ G-6 DCS G-2 DCS G-2 DCS G-3 DCS G-3 DASDAS ACSIM/ IMCOM...Army Ch of Staff Army Figure 1 – Army Stakeholders in Policy Process18 The Office of the ASA-I& E has responsibility for policy development
Dankner, R E; Wedner, H J
1983-11-01
A patient with a history of asthma induced by acetylsalicylic acid (ASA) was found to be ASA sensitive when orally challenged with ASA. She was successfully desensitized using incremental doses of ASA given orally and maintained on ASA or other nonsteroidal antiinflammatory (NSAI) agents for the treatment of arthritis. After 6 months of uninterrupted therapy the patient developed asthmatic symptoms that were related to ASA and NSAI drug therapy. Although desensitization may be achieved in patients with ASA-sensitive asthma, sensitivity may recur despite continuous therapy.
Gautier, Hélène; Massot, Capucine; Stevens, Rebecca; Sérino, Sylvie; Génard, Michel
2009-02-01
The mechanisms involving light control of vitamin C content in fruits are not yet fully understood. The present study aimed to evaluate the impact of fruit and leaf shading on ascorbate (AsA) accumulation in tomato fruit and to determine how fruit sugar content (as an AsA precursor) affected AsA content. Cherry tomato plants were grown in a glasshouse. The control treatment (normally irradiated fruits and irradiated leaves) was compared with the whole-plant shading treatment and with leaf or fruit shading treatments in fruits harvested at breaker stage. In a second experiment, the correlation between sugars and AsA was studied during ripening. Fruit shading was the most effective treatment in reducing fruit AsA content. Under normal conditions, AsA and sugar content were correlated and increased with the ripening stage. Reducing fruit irradiance strongly decreased the reduced AsA content (-74 %), without affecting sugars, so that sugar and reduced AsA were no longer correlated. Leaf shading delayed fruit ripening: it increased the accumulation of oxidized AsA in green fruits (+98 %), whereas it decreased the reduced AsA content in orange fruits (-19 %), suggesting that fruit AsA metabolism also depends on leaf irradiance. Under fruit shading only, the absence of a correlation between sugars and reduced AsA content indicated that fruit AsA content was not limited by leaf photosynthesis or sugar substrate, but strongly depended on fruit irradiance. Leaf shading most probably affected fruit AsA content by delaying fruit ripening, and suggested a complex regulation of AsA metabolism which depends on both fruit and leaf irradiance and fruit ripening stage.
Raschka, C; Koch, H J
2001-01-01
We studied the ASA pharmacokinetics of single doses of 500 mg and 1000 mg of D,L-lysine-monoacetylsalicylate (Lys-ASA) administered both orally (Delgesic) and 500 mg parenterally (Aspisol) as well as 500 mg acetylsalicylate (ASA, Aspirin) in 13 healthy volunteers. Blood samples were taken before and at defined times up to 48 h after application of Lys-ASA and ASA. Analysis for ASA and its metabolite salicylic acid were performed by HPLC. All concentration versus time data were presented descriptively. As far as ASA was concerned, differences were assessed by means of ANOVA according to Friedman including post hoc Wilcoxon tests for each time point. Pharmacokinetic parameters were calculated based on a one-compartment model. The concentration vs. time curves after oral intake of 500 mg of ASA and Lys-ASA differed significantly (p < 0.001). Peak serum ASA concentrations (Cmax) were 6.8 mg/l for oral Lys-ASA and 2.7 mg/l for ASA per os. The corresponding tmax-values were 14.2 and 38.0 min. Absolute bioavailabilities for 500 mg doses were 75.4 and 63.4 pour cent, respectively. After intake of 100 mg and 1000 mg oral doses of Lys-ASA Cmax was 2.7 mg/l and 15.9 mg/l, tmax being 14.2 min for the 1000 mg dose. The shortest half-life was found after i.v. injection with 7.5 min. Metabolism was fast with maximum rise of salicylic acid concentration after injection of Lys-ASS. We conclude that concerning time dimension oral administration of Lys-ASA is almost equivalent to i.v. Lys-ASA and may be an alternative for i.v. administration in cases of acute heart attacks.
Gautier, Hélène; Massot, Capucine; Stevens, Rebecca; Sérino, Sylvie; Génard, Michel
2009-01-01
Background and Aims The mechanisms involving light control of vitamin C content in fruits are not yet fully understood. The present study aimed to evaluate the impact of fruit and leaf shading on ascorbate (AsA) accumulation in tomato fruit and to determine how fruit sugar content (as an AsA precursor) affected AsA content. Methods Cherry tomato plants were grown in a glasshouse. The control treatment (normally irradiated fruits and irradiated leaves) was compared with the whole-plant shading treatment and with leaf or fruit shading treatments in fruits harvested at breaker stage. In a second experiment, the correlation between sugars and AsA was studied during ripening. Key Results Fruit shading was the most effective treatment in reducing fruit AsA content. Under normal conditions, AsA and sugar content were correlated and increased with the ripening stage. Reducing fruit irradiance strongly decreased the reduced AsA content (−74 %), without affecting sugars, so that sugar and reduced AsA were no longer correlated. Leaf shading delayed fruit ripening: it increased the accumulation of oxidized AsA in green fruits (+98 %), whereas it decreased the reduced AsA content in orange fruits (−19 %), suggesting that fruit AsA metabolism also depends on leaf irradiance. Conclusions Under fruit shading only, the absence of a correlation between sugars and reduced AsA content indicated that fruit AsA content was not limited by leaf photosynthesis or sugar substrate, but strongly depended on fruit irradiance. Leaf shading most probably affected fruit AsA content by delaying fruit ripening, and suggested a complex regulation of AsA metabolism which depends on both fruit and leaf irradiance and fruit ripening stage. PMID:19033285
McMullan, Kathryn L; Wedner, H James
2013-01-01
Aspirin (ASA) is the drug of choice in patients with coronary artery disease for primary and secondary prevention. This poses a problem for those patients reporting hypersensitivity to this drug or class of drugs. Desensitization to ASA may be carried out safely and effectively in patients with reported ASA or nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity needing ASA for cardiac indications. Our 7-step protocol is one choice for a rapid desensitization protocol. A retrospective chart review was conducted evaluating ASA desensitization in patients with reported ASA or NSAID hypersensitivity and a cardiac indication for ASA. In 160 evaluations over 15 years, 89 desensitizations were performed in both the inpatient and outpatient setting with only 16 reactions (18%). Eleven of these 16 patients (68.7%) were able to take daily ASA. Twenty-six desensitization procedures were performed with our 7-step rapid desensitization protocol in 10 inpatients and 16 outpatients with 3 reactions (18.75% of reactions). Initial reaction to ASA involving angioedema and reacting to ASA within the past year increased the risk of having a reaction to desensitization. Desensitization may be safely performed in patients with reported ASA or NSAID hypersensitivity and a cardiac indication for ASA. Our 7-step rapid protocol may be used in both the inpatient and outpatient setting to desensitize these patients. Patients who had angioedema with ASA ingestion or a reaction to ASA within the past year are at higher risk for reaction during the desensitization protocol. The authors have no funding, financial relationships, or conflicts of interest to disclose. © 2012 Wiley Periodicals, Inc.
Gehrke, Iris; Razavi, Regina; Poll-Wolbeck, Simon Jonas; Berkessel, Albrecht; Hallek, Michael; Kreuzer, Karl-Anton
2011-10-01
Chronic Lymphocytic Leukemia (CLL) is not curable in patients that are not eligible for allogeneic stem cell transplantation. Therefore, new treatment options are highly desirable. Chemically modified nonsteroidal anti-inflammatory drugs (NSAIDs), such as nitric-oxide-donating acetylsalicylic acid (NO-ASA), have been described to possess antineoplastic capacity. Recently, we could demonstrate a potent apoptosis induction in primary CLL cells in vitro and tumor growth inhibition by para-NO-ASA in a xenograft mouse model. However, little is known about the impact of positional isomerism of NO-ASA on its antineoplastic capacity in CLL. Primary CLL cells were treated with the meta-or para-isomer of NO-ASA at varying concentrations and durations. Viability was assessed flow cytometrically by annexin V-FITC/PI staining and by CellTiter-Glo luminescence cell viability assay. Caspase and PARP cleavage as well as involvement of β-catenin/Lef-1 signaling was determined by immunoblotting. For caspase inhibition, BD™ ApoBlock was used. Nude mice were xenografted with JVM3 cells and treated with meta-NO-ASA, para-NO-ASA or vehicle control. The meta-isomer was entirely ineffective in inducing CLL cell apoptosis in concentrations up to 100 μM, while para-NO-ASA acted in the low micromolar range. meta-NO-ASA, in contrast to para-NO-ASA, did not alter caspase activity. While para-NO-ASA action involved inhibition of β-catenin/Lef-1 signaling, meta-NO-ASA did not show any impact on this signaling pathway. Further, meta-NO-ASA did not significantly reduce tumor growth in a CLL xenograft mouse model, while para-NO-ASA was highly potent. We conclude that positional isomerism is crucial for the antineoplastic effect of NO-ASA in CLL. It can be suggested that the para-isomer, but not the meta-isomer, generates a chemical structure which is essential for the neoplastic effect of NO-ASA.
Frequency of Atrial Septal Aneurysms in Patients with Cerebral Ischemic Events
NASA Technical Reports Server (NTRS)
Agmon, Yoram; Khandheria, Bijoy K.; Meissner, Irene; Gentile, Federico; Whisnant, Jack P.; Sicks, JoRean D.; O'Fallon, W. Michael; Covalt, Jody L.; Wiebers, David O.; Seward, James B.
1999-01-01
Background-Atrial septal aneurysm (ASA) is a putative risk factor for cardioembolism. However, the frequency of ASA in the general population has not been adequately determined. Therefore, the frequency in patients with cerebral ischemic events, compared with the frequency in the general population, is poorly defined. We sought to determine the frequency of ASA in the general population and to compare the frequency of ASA in patients with cerebral ischemic events with the frequency in the general population. Methods and Results-The frequency of ASA in the population was determined in 363 subjects, a sample of the participants in the Stroke Prevention: Assessment of Risk in a Community study (control subjects), and was compared with the frequency in 355 age- and sex-matched patients undergoing transesophageal echocardiography in search of a cardiac source of embolism after a focal cerebral ischemic event. The proportion with ASA was 7.9% in patients versus 2.2% in control subjects (P=0.002; odds ratio of ASA, 3.65; 95% CI, 1.64 to 8.13, in patients versus control subjects). Patent foramen ovale (PFO) was detected with contrast injections in 56% of subjects with ASA. The presence of ASA predicted the presence of PFO (odds ratio of PFO, 4.57; 95% CI, 2.18 to 9.57, in subjects with versus those without ASA). In 86% of subjects with ASA and cerebral ischemia, transesophageal echocardiography did not detect an alternative source of cardioembolism other than an associated PFO. Conclusions-The prevalence of ASA based on this population-based study is 2.2%. The frequency of ASA is relatively higher in patients evaluated with transesophageal echocardiography after a cerebral ischemic event. ASA is frequently associated with PFO, suggesting paradoxical embolism as a mechanism of cardioembolism. In patients with cerebral ischemia and ASA, ASA (with or without PFO) commonly is the only potential cardioembolic source detected with transesophageal echocardiography.
Gehrke, Iris; Razavi, Regina; Poll-Wolbeck, Simon Jonas; Berkessel, Albrecht; Hallek, Michael; Kreuzer, Karl-Anton
2011-01-01
Background: Chronic Lymphocytic Leukemia (CLL) is not curable in patients that are not eligible for allogeneic stem cell transplantation. Therefore, new treatment options are highly desirable. Chemically modified nonsteroidal anti-inflammatory drugs (NSAIDs), such as nitric-oxide-donating acetylsalicylic acid (NO-ASA), have been described to possess antineoplastic capacity. Recently, we could demonstrate a potent apoptosis induction in primary CLL cells in vitro and tumor growth inhibition by para-NO-ASA in a xenograft mouse model. However, little is known about the impact of positional isomerism of NO-ASA on its antineoplastic capacity in CLL. Methods: Primary CLL cells were treated with the meta-or para-isomer of NO-ASA at varying concentrations and durations. Viability was assessed flow cytometrically by annexin V-FITC/PI staining and by CellTiter-Glo luminescence cell viability assay. Caspase and PARP cleavage as well as involvement of β-catenin/Lef-1 signaling was determined by immunoblotting. For caspase inhibition, BD™ ApoBlock was used. Nude mice were xenografted with JVM3 cells and treated with meta-NO-ASA, para-NO-ASA or vehicle control. Results: The meta-isomer was entirely ineffective in inducing CLL cell apoptosis in concentrations up to 100 μM, while para-NO-ASA acted in the low micromolar range. meta-NO-ASA, in contrast to para-NO-ASA, did not alter caspase activity. While para-NO-ASA action involved inhibition of β-catenin/Lef-1 signaling, meta-NO-ASA did not show any impact on this signaling pathway. Further, meta-NO-ASA did not significantly reduce tumor growth in a CLL xenograft mouse model, while para-NO-ASA was highly potent. Conclusion: We conclude that positional isomerism is crucial for the antineoplastic effect of NO-ASA in CLL. It can be suggested that the para-isomer, but not the meta-isomer, generates a chemical structure which is essential for the neoplastic effect of NO-ASA. PMID:23556096
NASA Astrophysics Data System (ADS)
Qiao, Yu; Liu, Xuejiao; Chen, Minxin; Lu, Benzhuo
2016-04-01
The hard sphere repulsion among ions can be considered in the Poisson-Nernst-Planck (PNP) equations by combining the fundamental measure theory (FMT). To reduce the nonlocal computational complexity in 3D simulation of biological systems, a local approximation of FMT is derived, which forms a local hard sphere PNP (LHSPNP) model. In the derivation, the excess chemical potential from hard sphere repulsion is obtained with the FMT and has six integration components. For the integrands and weighted densities in each component, Taylor expansions are performed and the lowest order approximations are taken, which result in the final local hard sphere (LHS) excess chemical potential with four components. By plugging the LHS excess chemical potential into the ionic flux expression in the Nernst-Planck equation, the three dimensional LHSPNP is obtained. It is interestingly found that the essential part of free energy term of the previous size modified model (Borukhov et al. in Phys Rev Lett 79:435-438, 1997; Kilic et al. in Phys Rev E 75:021502, 2007; Lu and Zhou in Biophys J 100:2475-2485, 2011; Liu and Eisenberg in J Chem Phys 141:22D532, 2014) has a very similar form to one term of the LHS model, but LHSPNP has more additional terms accounting for size effects. Equation of state for one component homogeneous fluid is studied for the local hard sphere approximation of FMT and is proved to be exact for the first two virial coefficients, while the previous size modified model only presents the first virial coefficient accurately. To investigate the effects of LHS model and the competitions among different counterion species, numerical experiments are performed for the traditional PNP model, the LHSPNP model, the previous size modified PNP (SMPNP) model and the Monte Carlo simulation. It's observed that in steady state the LHSPNP results are quite different from the PNP results, but are close to the SMPNP results under a wide range of boundary conditions. Besides, in both LHSPNP and SMPNP models the stratification of one counterion species can be observed under certain bulk concentrations.
Capture and separation of l-histidine through optimized zinc-decorated magnetic silica spheres.
Cardoso, Vanessa F; Sebastián, Víctor; Silva, Carlos J R; Botelho, Gabriela; Lanceros-Méndez, Senentxu
2017-09-01
Zinc-decorated magnetic silica spheres were developed, optimized and tested for the capture and separation of l-histidine. The magnetic silica spheres were prepared using a simple sol-gel method and show excellent magnetic characteristics, adsorption capacity toward metal ions, and stability in aqueous solution in a wide pH range. The binding capacity of zinc-decorated magnetic silica spheres to histidine proved to be strongly influenced by the morphology, composition and concentration of metal at the surface of the magnetic silica spheres and therefore these parameters should be carefully controlled in order to maximize the performance for protein purification purposes. Optimized zinc-decorated magnetic silica spheres demonstrate a binding capacity to l-histidine of approximately 44mgg -1 at the optimum binding pH buffer. Copyright © 2017 Elsevier B.V. All rights reserved.
Kim, Chohui; Choi, Hongsik; Kim, Jae Ik; Lee, Sangheon; Kim, Jinhyun; Lee, Woojin; Hwang, Taehyun; Kang, Suji; Moon, Taeho; Park, Byungwoo
2014-01-01
A scattering layer is utilized by mixing nanoporous spheres and nanoparticles in ZnO-based dye-sensitized solar cells. Hundred-nanometer-sized ZnO spheres consisting of approximately 35-nm-sized nanoparticles provide not only effective light scattering but also a large surface area. Furthermore, ZnO nanoparticles are added to the scattering layer to facilitate charge transport and increase the surface area as filling up large voids. The mixed scattering layer of nanoparticles and nanoporous spheres on top of the nanoparticle-based electrode (bilayer geometry) improves solar cell efficiency by enhancing both the short-circuit current (J sc) and fill factor (FF), compared to the layer consisting of only nanoparticles or nanoporous spheres.
Huang, Ming; Xu, Qiang; Deng, Xiu-Xin
2014-09-01
Chestnut rose (Rosa roxburghii Tratt) is a fruit crop that contains unusually high levels of l-ascorbic acid (AsA; ∼1300 mg 100g(-1) FW). To explore the mechanisms underlying AsA metabolism, we investigated the distribution and abundance of AsA during fruit development. We also analyzed gene expression patterns, enzyme activities, and content of metabolites related to AsA biosynthesis and recycling. AsA first accumulated during late fruit development and continued to accumulate during ripening, with the highest accumulation rate near fruit maturity. The redox state of AsA in fruit was also enhanced during late fruit development, while leaf and other tissues had much lower levels of AsA and the redox state of AsA was lower. In mature fruit, AsA was mainly distributed in the cytoplasm of the mesocarp. Correlation analysis suggested that the gene expression patterns, enzyme activities, and related metabolite concentrations involved in the l-galactose pathway showed relatively high correlations with the accumulation rate of AsA. The gene expression pattern and activity of dehydroascorbate reductase (DHAR, EC 1.8.5.1) correlated strongly with AsA concentration, possibly indicating the crucial role of DHAR in the accumulation of high levels of AsA in chestnut rose fruit. Over expression of DHAR in Arabidopsis significantly increased the reduced AsA content and redox state. This was more effective than over expression of the l-galactose pathway gene GDP-d-mannose-3,5-epimerase (EC 5.1.3.18). These findings will enhance understanding of the molecular mechanisms regulating accumulation of AsA in chestnut rose. Copyright © 2014 Elsevier GmbH. All rights reserved.
Sandor, B; Papp, J; Mozsik, Gy; Szolcsanyi, J; Keszthelyi, Zs; Juricskay, I; Toth, K; Habon, Tamas
2014-12-01
Capsaicin is a well-known component of red pepper. Recent studies have shown that capsaicin could prevent gastric ulcer provoked by various NSAID-s like acetylsalicylic acid (ASA). Primary objective of this human clinical phase I trial was to investigate whether two different doses of capsaicin co-administered with ASA could alter the inhibitory effect of ASA on platelet aggregation. 15 healthy male subjects were involved in the study and treated orally with 400 μg capsaicin, 800 μg capsaicin, 500 mg ASA, 400 μg capsaicin+500 mg ASA and 800 μg capsaicin+500 mg ASA. Blood was drawn before and 1, 2, 6 and 24 hours after the drug administration. After that epinephrine induced platelet aggregation was measured by optical aggregometry. Between treatments, volunteers had a 6-day wash-out period. Our results showed that capsaicin had no effect on platelet aggregation, while as expected, ASA monotherapy resulted in a significant and clinically effective platelet aggregation inhibition (p ≤ 0.001). The combined ASA-capsaicin therapies reached equivalent effectiveness in platelet aggregation inhibition as ASA monotherapy. Our investigation proved that capsaicin did not influence the inhibitory effect of ASA on platelet aggregation, thus the capsaicin-ASA treatment would combine the antiplatelet effect of ASA with the possible gastroprotection of capsaicin.
Shin, Yoshimura; Kentaro, Kawano; Ryusuke, Matsumura; Narumi, Sugihara; Koji, Furuno
2009-01-01
N-acetyl 5-aminosalicylic acid (5-AcASA) that was intracellularly formed from 5-aminosalicylic acid (5-ASA) at 200 μM was discharged 5.3, 7.1, and 8.1-fold higher into the apical site than into the basolateral site during 1, 2, and 4-hour incubations, respectively, in Caco-2 cells grown in Transwells. The addition of flavonols (100 μM) such as fisetin and quercetin with 5-ASA remarkably decreased the apically directed efflux of 5-AcASA. When 5-ASA (200 μM) was added to Caco-2 cells grown in tissue culture dishes, the formation of 5-AcASA decreased, and, in addition, the formed 5-AcASA was found to be accumulated within the cells in the presence of such flavonols. Thus, the decrease in 5-AcASA efflux by such flavonols was attributed not only to the inhibition of N-acetyl-conjugation of 5-ASA but to the predominant cellular accumulation of 5-AcASA. Various flavonoids also had both of the effects with potencies that depend on their specific structures. The essential structure of flavonoids was an absence of a hydroxyl substitution at the C5 position on the A-ring of flavone structure for the inhibitory effect on the N-acetyl-conjugation of 5-ASA, and a presence of hydroxyl substitutions at the C3′ or C4′ position on the B-ring of flavone structure for the promoting effect on the cellular accumulation of 5-AcASA. Both the decrease in 5-AcASA apical efflux and the increase in 5-AcASA cellular accumulation were also caused by MK571 and indomethacin, inhibitors of MRPs, but not by quinidine, cyclosporin A, P-glycoprotein inhibitors, and mitoxantrone, a BCRP substrate. These results suggest that certain flavonoids suppress the apical efflux of 5-AcASA possibly by inhibiting MRPs pumps located on apical membranes in Caco-2 cells. PMID:19688110
Bulley, Sean M; Rassam, Maysoon; Hoser, Dana; Otto, Wolfgang; Schünemann, Nicole; Wright, Michele; MacRae, Elspeth; Gleave, Andrew; Laing, William
2009-01-01
Vitamin C (L-ascorbic acid, AsA) is an essential metabolite for plants and animals. Kiwifruit (Actinidia spp.) are a rich dietary source of AsA for humans. To understand AsA biosynthesis in kiwifruit, AsA levels and the relative expression of genes putatively involved in AsA biosynthesis, regeneration, and transport were correlated by quantitative polymerase chain reaction in leaves and during fruit development in four kiwifruit genotypes (three species; A. eriantha, A. chinensis, and A. deliciosa). During fruit development, fruit AsA concentration peaked between 4 and 6 weeks after anthesis with A. eriantha having 3-16-fold higher AsA than other genotypes. The rise in AsA concentration typically occurred close to the peak in expression of the L-galactose pathway biosynthetic genes, particularly the GDP-L-galactose guanyltransferase gene. The high concentration of AsA found in the fruit of A. eriantha is probably due to higher expression of the GDP-mannose-3',5'-epimerase and GDP-L-galactose guanyltransferase genes. Over-expression of the kiwifruit GDP-L-galactose guanyltransferase gene in Arabidopsis resulted in up to a 4-fold increase in AsA, while up to a 7-fold increase in AsA was observed in transient expression studies where both GDP-L-galactose guanyltransferase and GDP-mannose-3',5'-epimerase genes were co-expressed. These studies show the importance of GDP-L-galactose guanyltransferase as a rate-limiting step to AsA, and demonstrate how AsA can be significantly increased in plants.
NASA Astrophysics Data System (ADS)
Klatt, Michael A.; Torquato, Salvatore
2018-01-01
In the first two papers of this series, we characterized the structure of maximally random jammed (MRJ) sphere packings across length scales by computing a variety of different correlation functions, spectral functions, hole probabilities, and local density fluctuations. From the remarkable structural features of the MRJ packings, especially its disordered hyperuniformity, exceptional physical properties can be expected. Here we employ these structural descriptors to estimate effective transport and electromagnetic properties via rigorous bounds, exact expansions, and accurate analytical approximation formulas. These property formulas include interfacial bounds as well as universal scaling laws for the mean survival time and the fluid permeability. We also estimate the principal relaxation time associated with Brownian motion among perfectly absorbing traps. For the propagation of electromagnetic waves in the long-wavelength limit, we show that a dispersion of dielectric MRJ spheres within a matrix of another dielectric material forms, to a very good approximation, a dissipationless disordered and isotropic two-phase medium for any phase dielectric contrast ratio. We compare the effective properties of the MRJ sphere packings to those of overlapping spheres, equilibrium hard-sphere packings, and lattices of hard spheres. Moreover, we generalize results to micro- and macroscopically anisotropic packings of spheroids with tensorial effective properties. The analytic bounds predict the qualitative trend in the physical properties associated with these structures, which provides guidance to more time-consuming simulations and experiments. They especially provide impetus for experiments to design materials with unique bulk properties resulting from hyperuniformity, including structural-color and color-sensing applications.
Correa-Basurto, José; Rosales Hernández, Martha Cecilia; Padilla Martínez, Itzia Irene; Mendieta-Wejebe, Jessica Elena
2016-01-01
5-[(4-carboxybutanoyl)amino]-2-hydroxybenzoic acid (C2) is a novel synthetic derivative of 5-aminosalicylic acid (5-ASA), which is currently being evaluated ex vivo as an anti-inflammatory agent and has shown satisfactory results. This study aimed to obtain the pharmacokinetic profiles, tissue distribution and plasma protein binding of C2 in Wistar Rats. Additionally, an HPLC method was developed and validated to quantify C2 in rat plasma. The pharmacokinetic profiles of intragastric, intravenous and intraperitoneal administration routes at singles doses of 100, 50, and 100 mg/kg, respectively, were studied in Wistar rats. The elimination half-life of intravenously administered C2 was approximately 33 min. The maximum plasma level of C2 was reached approximately 24 min after intragastric administration, with a Cmax value of 2.5 g/mL and an AUCtot value of 157 μg min-1/mL; the oral bioavailability was approximately 13%. Following a single intragastric or oral dose (100 mg/kg), C2 was distributed and detected in all examined tissues (including the brain and colon). The results showed that C2 accumulates over time. The plasma protein binding results indicated that the unbound fraction of C2 at concentrations of 1 to 20 μg/mL ranged from 89.8% to 92.5%, meaning that this fraction of C2 is available to cross tissues. Finally, the blood-plasma partitioning (BP ratio) of C2 in rat plasma was 0.71 and 0.6 at concentrations of 5 and 10 μg/mL, respectively, which indicates that C2 is free in the plasmatic phase and not inside blood cells. The results of this study suggest that a fraction of the administered C2 dose is absorbed in the stomach, and the fraction that is not absorbed reaches the small intestine and colon. This distribution constitutes the main advantage of C2 compared with 5-ASA for the treatment of ulcerative colitis (UC) and Crohn's disease (CD). PMID:27454774
Oral 5-aminosalicylic acid for induction of remission in ulcerative colitis.
Feagan, Brian G; Macdonald, John K
2012-10-17
Oral 5-aminosalicylic acid (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs in doses of at least 2 g/day, were more effective than placebo but no more effective than SASP for inducing remission in ulcerative colitis. This updated review includes more recent studies and evaluates the efficacy and safety of 5-ASA preparations used for the treatment of mild to moderately active ulcerative colitis. The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for induction of remission in active ulcerative colitis. A secondary objective of this systematic review was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens. A computer-assisted literature search for relevant studies (inception to January 20, 2012) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies. Studies were accepted for analysis if they were randomized controlled clinical trials of parallel design, with a minimum treatment duration of four weeks. Studies of oral 5-ASA therapy for treatment of patients with active ulcerative colitis compared with placebo, SASP or other formulations of 5-ASA were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA (two or three times daily) and 5-ASA dose ranging studies were also considered for inclusion. The outcomes of interest were the failure to induce global/clinical remission, global/clinical improvement, endoscopic remission, endoscopic improvement, adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. SASP-controlled trials were subgrouped by 5-ASA/SASP mass ratios. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol, Claversal, Salofalk and Pentasa). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the relative risk (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention to treat basis. Forty-eight studies (7776 patients) were included. The majority of included studies were rated as low risk of bias. 5-ASA was significantly superior to placebo with regard to all measured outcome variables. Seventy-two per cent of 5-ASA patients failed to enter clinical remission compared to 85% of placebo patients (RR 0.86, 95% CI 0.81 to 0.91). A dose-response trend for 5-ASA was also observed. No statistically significant differences in efficacy were found between 5-ASA and SASP. Fifty-four per cent of 5-ASA patients failed to enter remission compared to 58% of SASP patients (RR 0.90, 95% CI 0.77 to 1.04). No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Forty-two per cent of once daily patients failed to enter clinical remission compared to 44% of conventionally dosed patients (RR 0.95, 95% CI 0.82 to 1.10). Eight per cent of patients dosed once daily failed to adhere to their medication regimen compared to 6% of conventionally dosed patients (RR 1.36, 95% CI 0.64 to 2.86). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Forty-eight per cent of patients in the 5-ASA group failed to enter remission compared to 50% of patients in the 5-ASA comparator group (RR 0.94, 95% CI 0.86 to 1.03). A pooled analysis of the ASCEND (I, II and III, n = 1459 patients) studies found no statistically significant difference in clinical improvement between Asacol 4.8 g/day and 2.4 g/day used for the treatment of moderately active ulcerative colitis. Thirty-seven per cent of patients in the 4.8 g/day group failed to improve clinically compared to 41% of patients in the 2.4 g/day group (RR 0.89; 95% CI 0.78 to 1.01). Subgroup analysis indicated that patients with moderate disease may benefit from the higher dose of 4.8 g/day. One study compared (n = 123 patients) Pentasa 4 g/day to 2.25 g/day in patients with moderate disease. Twenty-five per cent of patients in the 4 g/day group failed to improve clinically compared to 57% of patients in the 2.25 g/day group (RR 0.44; 95% CI 0.27 to 0.71). A pooled analysis of two studies comparing MMX mesalamine 4.8 g/day to 2.4 g/day found no statistically significant difference in efficacy (RR 1.03, 95% CI 0.82 to 1.29). 5-ASA was generally safe and common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache and worsening ulcerative colitis. There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulation and 5-ASA dose ranging (high dose versus low dose) studies. SASP was not as well tolerated as 5-ASA. Twenty-nine percent of SASP patients experienced an adverse event compared to 15% of 5-ASA patients (RR 0.48, 95% CI 0.37 to 0.63). 5-ASA was superior to placebo and no more effective than SASP. Considering their relative costs, a clinical advantage to using oral 5-ASA in place of SASP appears unlikely. 5-ASA dosed once daily appears to be as efficacious and safe as conventionally dosed 5-ASA. Adherence does not appear to be enhanced by once daily dosing in the clinical trial setting. It is unknown if once daily dosing of 5-ASA improves adherence in a community-based setting. There do not appear to be any differences in efficacy or safety among the various 5-ASA formulations. A daily dosage of 2.4 g appears to be a safe and effective induction therapy for patients with mild to moderately active ulcerative colitis. Patients with moderate disease may benefit from an initial dose of 4.8 g/day.
Everall, Neil J; Priestnall, Ian M; Clarke, Fiona; Jayes, Linda; Poulter, Graham; Coombs, David; George, Michael W
2009-03-01
This paper describes preliminary investigations into the spatial resolution of macro attenuated total reflection (ATR) Fourier transform infrared (FT-IR) imaging and the distortions that arise when imaging intact, convex domains, using spheres as an extreme example. The competing effects of shallow evanescent wave penetration and blurring due to finite spatial resolution meant that spheres within the range 20-140 microm all appeared to be approximately the same size ( approximately 30-35 microm) when imaged with a numerical aperture (NA) of approximately 0.2. A very simple model was developed that predicted this extreme insensitivity to particle size. On the basis of these studies, it is anticipated that ATR imaging at this NA will be insensitive to the size of intact highly convex objects. A higher numerical aperture device should give a better estimate of the size of small spheres, owing to superior spatial resolution, but large spheres should still appear undersized due to the shallow sampling depth. An estimate of the point spread function (PSF) was required in order to develop and apply the model. The PSF was measured by imaging a sharp interface; assuming an Airy profile, the PSF width (distance from central maximum to first minimum) was estimated to be approximately 20 and 30 microm for IR bands at 1600 and 1000 cm(-1), respectively. This work has two significant limitations. First, underestimation of domain size only arises when imaging intact convex objects; if surfaces are prepared that randomly and representatively section through domains, the images can be analyzed to calculate parameters such as domain size, area, and volume. Second, the model ignores reflection and refraction and assumes weak absorption; hence, the predicted intensity profiles are not expected to be accurate; they merely give a rough estimate of the apparent sphere size. Much further work is required to place the field of quantitative ATR-FT-IR imaging on a sound basis.
Note: equation of state and the freezing point in the hard-sphere model.
Robles, Miguel; López de Haro, Mariano; Santos, Andrés
2014-04-07
The merits of different analytical equations of state for the hard-sphere system with respect to the recently computed high-accuracy value of the freezing-point packing fraction are assessed. It is found that the Carnahan-Starling-Kolafa and the branch-point approximant equations of state yield the best performance.
A numerical approximation to the elastic properties of sphere-reinforced composites
NASA Astrophysics Data System (ADS)
Segurado, J.; Llorca, J.
2002-10-01
Three-dimensional cubic unit cells containing 30 non-overlapping identical spheres randomly distributed were generated using a new, modified random sequential adsortion algorithm suitable for particle volume fractions of up to 50%. The elastic constants of the ensemble of spheres embedded in a continuous and isotropic elastic matrix were computed through the finite element analysis of the three-dimensional periodic unit cells, whose size was chosen as a compromise between the minimum size required to obtain accurate results in the statistical sense and the maximum one imposed by the computational cost. Three types of materials were studied: rigid spheres and spherical voids in an elastic matrix and a typical composite made up of glass spheres in an epoxy resin. The moduli obtained for different unit cells showed very little scatter, and the average values obtained from the analysis of four unit cells could be considered very close to the "exact" solution to the problem, in agreement with the results of Drugan and Willis (J. Mech. Phys. Solids 44 (1996) 497) referring to the size of the representative volume element for elastic composites. They were used to assess the accuracy of three classical analytical models: the Mori-Tanaka mean-field analysis, the generalized self-consistent method, and Torquato's third-order approximation.
Effective cluster model of dielectric enhancement in metal-insulator composites
NASA Astrophysics Data System (ADS)
Doyle, W. T.; Jacobs, I. S.
1990-11-01
The electrical permittivity of a suspension of conducting spheres at high volume loading exhibits a large enhancement above the value predicted by the Clausius-Mossotti approximation. The permittivity enhancement is a dielectric anomaly accompanying a metallization transition that occurs when conducting particles are close packed. In disordered suspensions, close encounters can cause a permittivity enhancement at any volume loading. We attribute the permittivity enhancements typically observed in monodisperse disordered suspensions of conducting spheres to local metallized regions of high density produced by density fluctuations. We model a disordered suspension as a mixture, or mesosuspension, of isolated spheres and random close-packed spherical clusters of arbitrary size. Multipole interactions within the clusters are treated exactly. External interactions between clusters and isolated spheres are treated in the dipole approximation. Model permittivities are compared with Guillien's experimental permittivity measurements [Ann. Phys. (Paris) Ser. 11, 16, 205 (1941)] on liquid suspensions of Hg droplets in oil and with Turner's conductivity measurements [Chem. Eng. Sci. 31, 487 (1976)] on fluidized bed suspensions of ion-exchange resin beads in aqueous solution. New permittivity measurements at 10 GHz on solid suspensions of monodisperse metal spheres in polyurethane are presented and compared with the model permittivities. The effective spherical cluster model is in excellent agreement with the experiments over the entire accessible range of volume loading.
Sector and Sphere: the design and implementation of a high-performance data cloud
Gu, Yunhong; Grossman, Robert L.
2009-01-01
Cloud computing has demonstrated that processing very large datasets over commodity clusters can be done simply, given the right programming model and infrastructure. In this paper, we describe the design and implementation of the Sector storage cloud and the Sphere compute cloud. By contrast with the existing storage and compute clouds, Sector can manage data not only within a data centre, but also across geographically distributed data centres. Similarly, the Sphere compute cloud supports user-defined functions (UDFs) over data both within and across data centres. As a special case, MapReduce-style programming can be implemented in Sphere by using a Map UDF followed by a Reduce UDF. We describe some experimental studies comparing Sector/Sphere and Hadoop using the Terasort benchmark. In these studies, Sector is approximately twice as fast as Hadoop. Sector/Sphere is open source. PMID:19451100
Controllable Fabrication and Optical Properties of Uniform Gadolinium Oxysulfate Hollow Spheres
Chen, Fashen; Chen, Gen; Liu, Tao; Zhang, Ning; Liu, Xiaohe; Luo, Hongmei; Li, Junhui; Chen, Limiao; Ma, Renzhi; Qiu, Guanzhou
2015-01-01
Uniform gadolinium oxysulfate (Gd2O2SO4) hollow spheres were successfully fabricated by calcination of corresponding Gd-organic precursor obtained via a facile hydrothermal process. The Gd2O2SO4 hollow spheres have a mean diameter of approximately 550 nm and shell thickness in the range of 30–70 nm. The sizes and morphologies of as-prepared Gd2O2SO4 hollow spheres could be deliberately controlled by adjusting the experimental parameters. Eu-doped Gd2O2SO4 hollow spheres have also been prepared for the property modification and practical applications. The structure, morphology, and properties of as-prepared products were characterized by XRD, TEM, HRTEM, SEM and fluorescence spectrophotometer. Excited with ultraviolet (UV) pump laser, successful downconversion (DC) could be achieved for Eu-doped Gd2O2SO4 hollow spheres. PMID:26671661
Bulley, Sean M.; Rassam, Maysoon; Hoser, Dana; Otto, Wolfgang; Schünemann, Nicole; Wright, Michele; MacRae, Elspeth; Gleave, Andrew; Laing, William
2009-01-01
Vitamin C (L-ascorbic acid, AsA) is an essential metabolite for plants and animals. Kiwifruit (Actinidia spp.) are a rich dietary source of AsA for humans. To understand AsA biosynthesis in kiwifruit, AsA levels and the relative expression of genes putatively involved in AsA biosynthesis, regeneration, and transport were correlated by quantitative polymerase chain reaction in leaves and during fruit development in four kiwifruit genotypes (three species; A. eriantha, A. chinensis, and A. deliciosa). During fruit development, fruit AsA concentration peaked between 4 and 6 weeks after anthesis with A. eriantha having 3–16-fold higher AsA than other genotypes. The rise in AsA concentration typically occurred close to the peak in expression of the L-galactose pathway biosynthetic genes, particularly the GDP-L-galactose guanyltransferase gene. The high concentration of AsA found in the fruit of A. eriantha is probably due to higher expression of the GDP-mannose-3′,5′-epimerase and GDP-L-galactose guanyltransferase genes. Over-expression of the kiwifruit GDP-L-galactose guanyltransferase gene in Arabidopsis resulted in up to a 4-fold increase in AsA, while up to a 7-fold increase in AsA was observed in transient expression studies where both GDP-L-galactose guanyltransferase and GDP-mannose-3′,5′-epimerase genes were co-expressed. These studies show the importance of GDP-L-galactose guanyltransferase as a rate-limiting step to AsA, and demonstrate how AsA can be significantly increased in plants. PMID:19129165
Antibiotic resistance due to an unusual ColE1-type replicon plasmid in Aeromonas salmonicida.
Vincent, Antony T; Emond-Rheault, Jean-Guillaume; Barbeau, Xavier; Attéré, Sabrina A; Frenette, Michel; Lagüe, Patrick; Charette, Steve J
2016-06-01
Aeromonas salmonicida subsp. salmonicida is a fish pathogen known to have a rich plasmidome. In the present study, we discovered an isolate of this bacterium bearing an additional unidentified small plasmid. After having sequenced the DNA of that isolate by next-generation sequencing, it appeared that the new small plasmid is a ColE1-type replicon plasmid, named here pAsa7. This plasmid bears a functional chloramphenicol-acetyltransferase-encoding gene (cat-pAsa7) previously unknown in A. salmonicida and responsible for resistance to chloramphenicol. A comparison of pAsa7 with pAsa2, the only known ColE1-type replicon plasmid usually found in A. salmonicida subsp. salmonicida, revealed that even if both plasmids share a high structural similarity, it is still unclear if pAsa7 is a derivative of pAsa2 since they showed several mutations at the nucleotide level. Transcriptomic analysis revealed that the cat-pAsa4 gene, another chloramphenicol-acetyltransferase-encoding gene, found on the large plasmid pAsa4, was significantly more transcribed than cat-pAsa7. This was correlated with a higher chloramphenicol resistance for isolates bearing pAsa4 compared with the one having pAsa7. Finally, a phylogenetic analysis showed that both CAT-pAsa4 and CAT-pAsa7 proteins were in different clusters. The clustering was supported by the identity of residues involved in the catalytic site. In addition, to give a better understanding of the large drug-resistance panel of A. salmonicida, this study reinforces the hypothesis that A. salmonicida subsp. salmonicida is a considerable reservoir for mobile genetic elements such as plasmids.
Ford, Alexander C; Khan, Khurram J; Achkar, Jean-Paul; Moayyedi, Paul
2012-02-01
Efficacy of 5-aminosalicylic acids (5-ASAs) in ulcerative colitis (UC) has been studied previously in meta-analyses. However, no recent meta-analysis has studied the relative efficacies of differing routes of administration. MEDLINE, EMBASE, and the Cochrane central register of controlled trials were searched (through May 2011). Eligible trials recruited adults with mildly to moderately active UC, or quiescent UC, and compared oral 5-ASAs with either topical 5-ASAs or a combination of oral and topical 5-ASAs. Dichotomous data were pooled to obtain relative risk (RR) of failure to achieve remission in active UC, and RR of relapse of disease activity in quiescent UC, with a 95% confidence interval (CI). The number needed to treat (NNT) was calculated from the reciprocal of the risk difference. The search identified 3,061 citations, and 12 randomized controlled trials (RCTs) were eligible. Four compared topical with oral 5-ASAs in active UC remission, with an RR of no remission with topical 5-ASAs of 0.82 (95% CI=0.52-1.28). Four trials compared combined with oral 5-ASAs in active UC (RR of no remission=0.65; 95% CI=0.47-0.91; NNT=5). Three RCTs compared intermittent topical with oral 5-ASAs in preventing relapse of quiescent UC (RR=0.64; 95% CI=0.43-0.95; NNT=4), and two compared combined with oral 5-ASAs (RR of relapse=0.48; 95% CI=0.17-1.38). Combined 5-ASA therapy appeared superior to oral 5-ASAs for induction of remission of mildly to moderately active UC. Intermittent topical 5-ASAs appeared superior to oral 5-ASAs for preventing relapse of quiescent UC.
Freezing of soft spheres: A critical test for weighted-density-functional theories
NASA Astrophysics Data System (ADS)
Laird, Brian B.; Kroll, D. M.
1990-10-01
We study the freezing properties of systems with inverse-power and Yukawa interactions (soft spheres), using recently developed weighted-density-functional theories. We find that the modified weighted-density-functional approximation (MWDA) of Denton and Ashcroft yields results for the liquid to face-centered-cubic (fcc) structure transition that represent a significant improvement over those of earlier ``second-order'' density-functional freezing theories; however, this theory, like the earlier ones, fails to predict any liquid to body-centered-cubic (bcc) transition, even under conditions where the computer simulations indicate that this should be the equilibrium solid structure. In addition, we show that both the modified effective-liquid approximation (MELA) of Baus [J. Phys. Condens. Matter 2, 2111 (1990)] and the generalized effective-liquid approximation of Lutsko and Baus [Phys. Rev. Lett. 64, 761 (1990)], while giving excellent results for the freezing of hard spheres, fail completely to predict freezing into either fcc or bcc solid phases for soft inverse-power potentials. We also give an alternate derivation of the MWDA that makes clearer its connection to earlier theories.
Oral 5-aminosalicylic acid for induction of remission in ulcerative colitis.
Wang, Yongjun; Parker, Claire E; Bhanji, Tania; Feagan, Brian G; MacDonald, John K
2016-04-21
Oral 5-aminosalicylic acid (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs in doses of at least 2 g/day, were more effective than placebo but no more effective than SASP for inducing remission in ulcerative colitis. This updated review includes more recent studies and evaluates the efficacy and safety of 5-ASA preparations used for the treatment of mild to moderately active ulcerative colitis. The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for induction of remission in active ulcerative colitis. A secondary objective of this systematic review was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens. A computer-assisted literature search for relevant studies (inception to July 9, 2015) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies. Studies were accepted for analysis if they were randomized controlled clinical trials of parallel design, with a minimum treatment duration of four weeks. Studies of oral 5-ASA therapy for treatment of patients with active ulcerative colitis compared with placebo, SASP or other formulations of 5-ASA were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA (two or three times daily) and 5-ASA dose ranging studies were also considered for inclusion. The outcomes of interest were the failure to induce global/clinical remission, global/clinical improvement, endoscopic remission, endoscopic improvement, adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. SASP-controlled trials were subgrouped by 5-ASA/SASP mass ratios. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol, Claversal, Salofalk and Pentasa). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the relative risk (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention-to-treat basis. Fifty-three studies (8548 patients) were included. The majority of included studies were rated as low risk of bias. 5-ASA was significantly superior to placebo with regard to all measured outcome variables. Seventy-one per cent of 5-ASA patients failed to enter clinical remission compared to 83% of placebo patients (RR 0.86, 95% CI 0.82 to 0.89). A dose-response trend for 5-ASA was also observed. No statistically significant differences in efficacy were found between 5-ASA and SASP. Fifty-four per cent of 5-ASA patients failed to enter remission compared to 58% of SASP patients (RR 0.90, 95% CI 0.77 to 1.04). No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Forty-five per cent of once daily patients failed to enter clinical remission compared to 48% of conventionally dosed patients (RR 0.94, 95% CI 0.83 to 1.07). Eight per cent of patients dosed once daily failed to adhere to their medication regimen compared to 6% of conventionally dosed patients (RR 1.36, 95% CI 0.64 to 2.86). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Fifty per cent of patients in the 5-ASA group failed to enter remission compared to 52% of patients in the 5-ASA comparator group (RR 0.94, 95% CI 0.86 to 1.02). A pooled analysis of 3 studies (n = 1459 patients) studies found no statistically significant difference in clinical improvement between Asacol 4.8 g/day and 2.4 g/day used for the treatment of moderately active ulcerative colitis. Thirty-seven per cent of patients in the 4.8 g/day group failed to improve clinically compared to 41% of patients in the 2.4 g/day group (RR 0.89; 95% CI 0.78 to 1.01). Subgroup analysis indicated that patients with moderate disease may benefit from the higher dose of 4.8 g/day. One study compared (n = 123 patients) Pentasa 4 g/day to 2.25 g/day in patients with moderate disease. Twenty-five per cent of patients in the 4 g/day group failed to improve clinically compared to 57% of patients in the 2.25 g/day group (RR 0.44; 95% CI 0.27 to 0.71). A pooled analysis of two studies comparing MMX mesalamine 4.8 g/day to 2.4 g/day found no statistically significant difference in efficacy (RR 1.03, 95% CI 0.82 to 1.29). There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulation and 5-ASA dose ranging (high dose versus low dose) studies. Common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache and worsening ulcerative colitis. SASP was not as well tolerated as 5-ASA. Twenty-nine percent of SASP patients experienced an adverse event compared to 15% of 5-ASA patients (RR 0.48, 95% CI 0.37 to 0.63). 5-ASA was superior to placebo and no more effective than SASP. Considering their relative costs, a clinical advantage to using oral 5-ASA in place of SASP appears unlikely. 5-ASA dosed once daily appears to be as efficacious and safe as conventionally dosed 5-ASA. Adherence does not appear to be enhanced by once daily dosing in the clinical trial setting. It is unknown if once daily dosing of 5-ASA improves adherence in a community-based setting. There do not appear to be any differences in efficacy or safety among the various 5-ASA formulations. A daily dosage of 2.4 g appears to be a safe and effective induction therapy for patients with mild to moderately active ulcerative colitis. Patients with moderate disease may benefit from an initial dose of 4.8 g/day.
Development of paclitaxel-TyroSpheres for topical skin treatment
Kilfoyle, Brian E.; Sheihet, Larisa; Zhang, Zheng; Laohoo, Marissa; Kohn, Joachim; Michniak-Kohn, Bozena B.
2012-01-01
A potential topical psoriasis therapy has been developed consisting of tyrosine-derived nanospheres (TyroSpheres) with encapsulated anti-proliferative paclitaxel. TyroSpheres provide enhancement of paclitaxel solubility (almost 4,000 times greater than PBS) by effective encapsulation and enable sustained, dose-controlled release over 72 hours under conditions mimicking skin permeation. TyroSpheres offer potential in the treatment of psoriasis, a disease resulting from over-proliferation of keratinocytes in the basal layer of the epidermis, by (a) enabling delivery of paclitaxel into the epidermis at concentrations >100 ng/cm2 of skin surface area and (b) enhancing the cytotoxicity of loaded paclitaxel to human keratinocytes (IC50 of paclitaxel-TyroSpheres was approximately 45% lower than that of free paclitaxel). TyroSpheres were incorporated into a gel-like viscous formulation to improve their flow characteristics with no impact on homogeneity, release or skin distribution of the payload. The findings reported here confirm that the TyroSpheres provide a platform for paclitaxel topical administration allowing skin drug localization and minimal systemic escape. PMID:22732474
Singhatanadgit, Weerachai; Varodomrujiranon, Manatsanan
2013-12-01
The present study aimed to investigate the osteogenic potency of scaffold-free 3-dimensional (3D) spheres of periodontal ligament stem cells (PDLSCs). The osteogenic potency of PDLSC spheres was determined by the ability to form mineralization and to express key osteogenesis-associated genes. The alkaline phosphatase (ALP) activity and the protein content of PDLSC spheres were also measured. The 3D sphere developed its osteogenic potency in a time-dependent manner, containing approximately 10-fold higher mineralization, 5-fold higher protein content, and 4-fold greater ALP activity than those in the controls. The expression of key osteogenic genes was also upregulated in the 3D PDLSC spheres. Cellular outgrowth was observed when reintroduced into 2D culture. PDLSCs were able to undergo osteogenic differentiation in a scaffold-free 3D culture, producing bonelike mineralization in vitro. This suggests, at least in vitro, the osteogenic potency of the 3D PDLSC spheres. Copyright © 2013 Elsevier Inc. All rights reserved.
High-pressure polymorphism of acetylsalicylic acid (aspirin): Raman spectroscopy
NASA Astrophysics Data System (ADS)
Crowell, Ethan L.; Dreger, Zbigniew A.; Gupta, Yogendra M.
2015-02-01
Micro-Raman spectroscopy was used to elucidate the high-pressure polymorphic behavior of acetylsalicylic acid (ASA), an important pharmaceutical compound known as aspirin. Using a diamond anvil cell (DAC), single crystals of the two polymorphic phases of aspirin existing at ambient conditions (ASA-I and ASA-II) were compressed to 10 GPa. We found that ASA-I does not transform to ASA-II, but instead transforms to a new phase (ASA-III) above ∼2 GPa. It is demonstrated that this transformation primarily introduces structural changes in the bonding and arrangement of the acetyl groups and is reversible upon the release of pressure. In contrast, a less dense ASA-II shows no transition in the pressure range studied, though it appears to exhibit a disordered structure above 7 GPa. Our results suggest that ASA-III is the most stable polymorph of aspirin at high pressures.
Self-assembled clusters of spheres related to spherical codes.
Phillips, Carolyn L; Jankowski, Eric; Marval, Michelle; Glotzer, Sharon C
2012-10-01
We consider the thermodynamically driven self-assembly of spheres onto the surface of a central sphere. This assembly process forms self-limiting, or terminal, anisotropic clusters (N-clusters) with well-defined structures. We use Brownian dynamics to model the assembly of N-clusters varying in size from two to twelve outer spheres and free energy calculations to predict the expected cluster sizes and shapes as a function of temperature and inner particle diameter. We show that the arrangements of outer spheres at finite temperatures are related to spherical codes, an ideal mathematical sequence of points corresponding to the densest possible sphere packings. We demonstrate that temperature and the ratio of the diameters of the inner and outer spheres dictate cluster morphology. We present a surprising result for the equilibrium structure of a 5-cluster, for which the square pyramid arrangement is preferred over a more symmetric structure. We show this result using Brownian dynamics, a Monte Carlo simulation, and a free energy approximation. Our results suggest a promising way to assemble anisotropic building blocks from constituent colloidal spheres.
Chemical association in simple models of molecular and ionic fluids. III. The cavity function
NASA Astrophysics Data System (ADS)
Zhou, Yaoqi; Stell, George
1992-01-01
Exact equations which relate the cavity function to excess solvation free energies and equilibrium association constants are rederived by using a thermodynamic cycle. A zeroth-order approximation, derived previously by us as a simple interpolation scheme, is found to be very accurate if the associative bonding occurs on or near the surface of the repulsive core of the interaction potential. If the bonding radius is substantially less than the core radius, the approximation overestimates the association degree and the association constant. For binary association, the zeroth-order approximation is equivalent to the first-order thermodynamic perturbation theory (TPT) of Wertheim. For n-particle association, the combination of the zeroth-order approximation with a ``linear'' approximation (for n-particle distribution functions in terms of the two-particle function) yields the first-order TPT result. Using our exact equations to go beyond TPT, near-exact analytic results for binary hard-sphere association are obtained. Solvent effects on binary hard-sphere association and ionic association are also investigated. A new rule which generalizes Le Chatelier's principle is used to describe the three distinct forms of behaviors involving solvent effects that we find. The replacement of the dielectric-continuum solvent model by a dipolar hard-sphere model leads to improved agreement with an experimental observation. Finally, equation of state for an n-particle flexible linear-chain fluid is derived on the basis of a one-parameter approximation that interpolates between the generalized Kirkwood superposition approximation and the linear approximation. A value of the parameter that appears to be near optimal in the context of this application is obtained from comparison with computer-simulation data.
Gantwerker, Eric A; Bannos, Cassandra; Cunningham, Michael J; Rahbar, Reza
2017-01-01
To describe a surgical categorization system to create a universal nomenclature, delineating patient complexity as a first step toward developing a true risk stratification system. Retrospective database review of all otolaryngology surgical procedures performed in a tertiary pediatric hospital system over one academic year (July 2012-June 2013). All otolaryngology surgical procedures were reviewed, encompassing 8478 procedures on 5711 patients. The attending otolaryngologist assigned surgical scheduling category (SSCS) at the time of case booking based on an institution specific guidelines. The guidelines are as follow: Category I was assigned to American Society of Anesthesiologists physical status classification (ASA) I/II patients, designating them appropriate for institution's suburban ambulatory surgery centers; Category II was ASA I/II patients with social or transportation issues; Category III was ASA I/II patients who required case coordination with other medical or surgical departments; Category IV was reserved for patients of any ASA class whom the surgeon designated to be of a higher complexity. 8478 total procedures analyzed with 7198 having complete records. 48% were Category I, 13.6% were Category II, 1.9% were Category III and 36.5% were Category IV. The ASA were 34.7% ASA I, 50% ASA II, 13.39% ASA III, and 1.9% ASA IV. Although the largest proportion of patients were ASA II (50%), 39.6% of all ASA II were Category IV. Category IV was split into 54.2% ASA II and 34% ASA III and shows that peri-operative surgical concerns were not encompassed by the ASA system. This surgical categorization system streamlines surgical scheduling in a tertiary pediatric hospital system, particularly with respect to the designation of cases as ambulatory surgery center or main operating room appropriate. The case mix complexity is also readily apparent, enhancing recognition of the coordination and attention required for the perioperative management of high complexity patients. The SSCS helps convey concerns not addressed by ASA physical status alone. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Umamaheswari, R.; Yogeswari, M.; Kalpana, G.
2013-02-01
Self-consistent scalar relativistic band structure calculations for AMO (A=Li, Na, K and Rb; M=Ag and Cu) compounds have been performed using the tight-binding linear muffin-tin orbital (TB-LMTO) method within the local density approximation (LDA). At ambient conditions, these compounds are found to crystallize in tetragonal KAgO-type structure with two different space group I-4m2 and I4/mmm. Nowadays, hypothetical structures are being considered to look for new functional materials. AMO compounds have stoichiometry similar to eight-electron half-Heusler materials of type I-I-VI which crystallizes in cubic (C1b) MgAgAs-type structure with space group F-43m. For all these compounds, by interchanging the positions of atoms in the hypothetical cubic structure, three phases (α, β and γ) are formed. The energy-volume relation for these compounds in tetragonal KAgO-type structure and cubic α, β and γ phases of related structure have been obtained. Under ambient conditions these compounds are more stable in tetragonal KAgO-type (I4/mmm) structure. The total energies calculated within the atomic sphere approximation (ASA) were used to determine the ground state properties such as equilibrium lattice parameters, c/a ratio, bulk modulus, cohesive energy and are compared with the available experimental results. The results of the electronic band structure calculations at ambient condition show that LiCuO and NaMO are indirect band gap semiconductors whereas KMO and RbMO are direct band gap semiconductors. At high pressure the band gap decreases and the phenomenon of band overlap metallization occur. Also these compounds undergo structural phase transition from tetragonal I-4m2 phase to cubic α-phase and transition pressures were calculated.
Accelerating the coupled-cluster singles and doubles method using the chain-of-sphere approximation
NASA Astrophysics Data System (ADS)
Dutta, Achintya Kumar; Neese, Frank; Izsák, Róbert
2018-06-01
In this paper, we present a chain-of-sphere implementation of the external exchange term, the computational bottleneck of coupled-cluster calculations at the singles and doubles level. This implementation is compared to standard molecular orbital, atomic orbital and resolution of identity implementations of the same term within the ORCA package and turns out to be the most efficient one for larger molecules, with a better accuracy than the resolution-of-identity approximation. Furthermore, it becomes possible to perform a canonical CC calculation on a tetramer of nucleobases in 17 days, 20 hours.
Alós, Enriqueta; Rodrigo, María J; Zacarías, Lorenzo
2013-06-01
Sweet pepper (Capsicum annuum L.) is widely recognized among the vegetables with high content of ascorbic acid (AsA). However, the metabolic pathways involved in the biosynthesis, recycling and degradation of AsA and their relative contribution to the concentration of AsA have not been established yet. In the present work, the expression levels of selected genes involved in the AsA biosynthesis, degradation and recycling pathways were analyzed during development and ripening of pepper fruit cv. Palermo and in mature fruit of four cultivars (Lipari, C-116, Surrentino and Italverde) with different AsA concentrations. An inverse correlation was found between the expression of the biosynthetic genes and AsA concentrations, which could indicate that a feedback mechanism regulates AsA homeostasis in pepper fruits. Interestingly, analysis of mRNA levels of ascorbate oxidase, involved in the degradation of AsA, suggests that this enzyme plays a critical role in the regulation of the AsA pool during fruit development and ripening. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
2012-01-01
Background To gain insight into the regulation of fruit ascorbic acid (AsA) pool in tomatoes, a combination of metabolite analyses, non-labelled and radiolabelled substrate feeding experiments, enzyme activity measurements and gene expression studies were carried out in fruits of the ‘low-’ and ‘high-AsA’ tomato cultivars ‘Ailsa Craig’ and ‘Santorini’ respectively. Results The two cultivars exhibited different profiles of total AsA (totAsA, AsA + dehydroascorbate) and AsA accumulation during ripening, but both displayed a characteristic peak in concentrations at the breaker stage. Substrate feeding experiments demonstrated that the L-galactose pathway is the main AsA biosynthetic route in tomato fruits, but that substrates from alternative pathways can increase the AsA pool at specific developmental stages. In addition, we show that young fruits display a higher AsA biosynthetic capacity than mature ones, but this does not lead to higher AsA concentrations due to either enhanced rates of AsA breakdown (‘Ailsa Craig’) or decreased rates of AsA recycling (‘Santorini’), depending on the cultivar. In the later stages of ripening, differences in fruit totAsA-AsA concentrations of the two cultivars can be explained by differences in the rate of AsA recycling activities. Analysis of the expression of AsA metabolic genes showed that only the expression of one orthologue of GDP-L-galactose phosphorylase (SlGGP1), and of two monodehydroascorbate reductases (SlMDHAR1 and SlMDHAR3) correlated with the changes in fruit totAsA-AsA concentrations during fruit ripening in ‘Ailsa Craig’, and that only the expression of SlGGP1 was linked to the high AsA concentrations found in red ripe ‘Santorini’ fruits. Conclusions Results indicate that ‘Ailsa Craig’ and ‘Santorini’ use complementary mechanisms to maintain the fruit AsA pool. In the low-AsA cultivar (‘Ailsa Craig’), alternative routes of AsA biosynthesis may supplement biosynthesis via L-galactose, while in the high-AsA cultivar (‘Santorini’), enhanced AsA recycling activities appear to be responsible for AsA accumulation in the later stages of ripening. Gene expression studies indicate that expression of SlGGP1 and two orthologues of SlMDHAR are closely correlated with totAsA-AsA concentrations during ripening and are potentially good candidates for marker development for breeding and selection. PMID:23245200
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wells, C.E.; Tichenor, D.A.; Martin, D.C.
1963-01-01
Freshly picked strawberries were irradiated in a gamma source and ascorbic acid (ASA) and its oxidative breakdown products were measured at intervals during 3 to 6 months' storage. Reduced ASA, dehydroascorbic acid (DHA), diketogulonic acid (DKA), and total ASA were determined in unirradiated strawberries and in strawberries receiving 0.3 and 0.8 Mrad. Irradiation caused a significant loss of total ASA. Storage at 35 un. Concent 85% F for 180 days resulted in further losses, most of which occurred during the first 95 days. Addition of a glucose oxidase packet to atmospheric packs did not affect retention of total ASA. Amore » significant amount of reduced ASA was destroyed by irradiation, the loss being greater at the higher level used. Relatively large amounts er irradiation in the presence of almost complete retention of total ASA indicated that the degradation followed the usual pattern: reduced ASA to DHA to DKA. After 180 days storage, practically all of the reduced ASA was destroyed in air-packed irradiated samples, but comparable glucose-oxidase-packed samples retained 33 to 47% of their original reduced ASA. Measurement of the Gardner a color value revealed a significant able color variability among samples. Color losses were higher at higher doses. (H.R.D.)« less
Exploring the impact of wounding and jasmonates on ascorbate metabolism
Suza, Walter P.; Avila, Carlos A.; Carruthers, Kelly; Kulkarni, Shashank; Goggin, Fiona L.; Lorence, Argelia
2010-01-01
Vitamin C (ascorbate, AsA) is the most abundant water-soluble antioxidant in plants. Ascorbate provides the first line of defense against damaging reactive oxygen species (ROS), and helps protect plant cells from many factors that induce oxidative stress, including wounding, ozone, high salinity, and pathogen attack. Plant defenses against these stresses are also dependent upon jasmonates (JAs), a class of plant hormones that promote ROS accumulation. Here, we review evidence showing that wounding and JAs influence AsA accumulation in various plant species, and we report new data from Arabidopsis and tomato testing the influence of JAs on AsA levels in wounded and unwounded plants. In both species, certain mutations that impair JA metabolism and signaling influence foliar AsA levels, suggesting that endogenous JAs may regulate steady-state AsA. However, the impact of wounding on AsA accumulation was similar in JA mutants and wild type controls, indicating that this wound response does not require JAs. Our findings also indicate that the effects of wounding and JAs on AsA accumulation differ between species; these factors both enhanced AsA accumulation in Arabidopsis, but depressed AsA levels in tomato. These results underscore the importance of obtaining data from more than one model species, and demonstrate the complexity of AsA regulation. PMID:20346686
Ascorbic acid metabolism during bilberry (Vaccinium myrtillus L.) fruit development.
Cocetta, Giacomo; Karppinen, Katja; Suokas, Marko; Hohtola, Anja; Häggman, Hely; Spinardi, Anna; Mignani, Ilaria; Jaakola, Laura
2012-07-15
Bilberry (Vaccinium myrtillus L.) possesses a high antioxidant capacity in berries due to the presence of anthocyanins and ascorbic acid (AsA). Accumulation of AsA and the expression of the genes encoding the enzymes of the main AsA biosynthetic route and of the ascorbate-glutathione cycle, as well as the activities of the enzymes involved in AsA oxidation and recycling were investigated for the first time during the development and ripening of bilberry fruit. The results showed that the AsA level remained relatively stable during fruit maturation. The expression of the genes encoding the key enzymes in the AsA main biosynthetic route showed consistent trends with each other as well as with AsA levels, especially during the first stages of fruit ripening. The expression of genes and activities of the enzyme involved in the AsA oxidation and recycling route showed more prominent developmental stage-dependent changes during the ripening process. Different patterns of activity were found among the studied enzymes and the results were, for some enzymes, in accordance with AsA levels. In fully ripe berries, both AsA content and gene expression were significantly higher in skin than in pulp. Copyright © 2012 Elsevier GmbH. All rights reserved.
Interaction between the LMWH reviparin and aspirin in healthy volunteers
Klinkhardt, Ute; Breddin, Hans Klaus; Esslinger, Heinz Ulrich; Haas, Silvia; Kalatzis, Andreas; Harder, Sebastian
2000-01-01
Aims To investigate potential interactions between reviparin and acetylsalicylic acid (ASA 300 mg o.d. from day 1–5). Methods In an open, randomized, three-way-cross over study nine healthy volunteers received reviparin (s.c. injection of 6300 anti-Xa units) or placebo from days 3 to 5 and acetylsalicylic acid (ASA 300 mg) or placebo from days 1 to 5. Assessments included bleeding time (BT), collagen (1 µg ml−1) induced platelet aggregation (CAG), heptest, plasma antifactor Xa-activity and activated partial thromboplastin time (aPTT). Results Median bleeding time at day 5 was 5.5 min after reverparin alone and after ASA alone and was 9.6 min after the combination of reviparin and ASA. ASA treatment reduced CAG from 84% to 40 to 50% of Amax; values after combined treatment of reviparin with ASA were not different from those after ASA alone. aPTT was prolonged to 32 s after reviparin; this effect was not modified if subjects received ASA. Combined treatment with ASA and reviparin had no effect on plasma anti-Xa-activity and heptest compared with reviparin alone. Conclusions We could not entirely exclude a small interaction between reviparin and ASA on bleeding time, but the effect is probably without clinical significance. PMID:10759689
ASA24-Kids (no longer available)
ASA24-Kids-2014 was released in February 2014 and until March 2017, researchers can register new studies in this version of the ASA24® system. Funding is not currently available for a mobile accessible version for kids, such as ASA24-2016.
Oral 5-aminosalicylic acid for maintenance of remission in ulcerative colitis.
Wang, Yongjun; Parker, Claire E; Feagan, Brian G; MacDonald, John K
2016-05-09
Oral 5-aminosalicylic (5-ASA) preparations were intended to avoid the adverse effects of sulfasalazine (SASP) while maintaining its therapeutic benefits. Previously, it was found that 5-ASA drugs were more effective than placebo but had a statistically significant therapeutic inferiority relative to SASP. This updated review includes more recent studies and evaluates the effectiveness, dose-responsiveness, and safety of 5-ASA preparations used for maintenance of remission in quiescent ulcerative colitis. The primary objectives were to assess the efficacy, dose-responsiveness and safety of oral 5-ASA compared to placebo, SASP, or 5-ASA comparators for maintenance of remission in quiescent ulcerative colitis. A secondary objective was to compare the efficacy and safety of once daily dosing of oral 5-ASA with conventional (two or three times daily) dosing regimens. A literature search for relevant studies (inception to 9 July 2015) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies. Studies were accepted for analysis if they were randomized controlled trials with a minimum treatment duration of six months. Studies of oral 5-ASA therapy for treatment of patients with quiescent ulcerative colitis compared with placebo, SASP or other 5-ASA formulations were considered for inclusion. Studies that compared once daily 5-ASA treatment with conventional dosing of 5-ASA and 5-ASA dose ranging studies were also considered for inclusion. The primary outcome was the failure to maintain clinical or endoscopic remission. Secondary outcomes included adherence, adverse events, withdrawals due to adverse events, and withdrawals or exclusions after entry. Trials were separated into five comparison groups: 5-ASA versus placebo, 5-ASA versus sulfasalazine, once daily dosing versus conventional dosing, 5-ASA versus comparator 5-ASA formulation, and 5-ASA dose-ranging. Placebo-controlled trials were subgrouped by dosage. Once daily versus conventional dosing studies were subgrouped by formulation. 5-ASA-controlled trials were subgrouped by common 5-ASA comparators (e.g. Asacol and Salofalk). Dose-ranging studies were subgrouped by 5-ASA formulation. We calculated the risk ratio (RR) and 95% confidence intervals (95% CI) for each outcome. Data were analyzed on an intention-to-treat basis. Forty-one studies (8928 patients) were included. The majority of included studies were rated as low risk of bias. Ten studies were rated at high risk of bias. Seven of these studies were single-blind and three studies were open-label. However, two open-label studies and four of the single-blind studies utilized investigator performed endoscopy as an endpoint, which may protect against bias. 5-ASA was significantly superior to placebo for maintenance of clinical or endoscopic remission. Forty-one per cent of 5-ASA patients relapsed compared to 58% of placebo patients (7 studies, 1298 patients; RR 0.69, 95% CI 0.62 to 0.77). There was a trend towards greater efficacy with higher doses of 5-ASA with a statistically significant benefit for the 1 to 1.9 g/day (RR 0.65; 95% CI 0.56 to 0.76) and the > 2 g/day subgroups (RR 0.73, 95% CI 0.60 to 0.89). SASP was significantly superior to 5-ASA for maintenance of remission. Forty-eight per cent of 5-ASA patients relapsed compared to 43% of SASP patients (12 studies, 1655 patients; RR 1.14, 95% CI 1.03 to 1.27). A GRADE analysis indicated that the overall quality of the evidence for the primary outcome for the placebo and SASP-controlled studies was high. No statistically significant differences in efficacy or adherence were found between once daily and conventionally dosed 5-ASA. Twenty-nine per cent of once daily patients relapsed over 12 months compared to 31% of conventionally dosed patients (8 studies, 3127 patients; RR 0.91, 95% CI 0.82 to 1.01). Eleven per cent of patients in the once daily group failed to adhere to their medication regimen compared to 9% of patients in the conventional dosing group (6 studies, 1462 patients; RR 1.22, 95% CI 0.91 to 1.64). There does not appear to be any difference in efficacy among the various 5-ASA formulations. Forty-four per cent of patients in the 5-ASA group relapsed compared to 41% of patients in the 5-ASA comparator group (6 studies, 707 patients; RR 1.08, 95% CI 0.91 to 1.28). A pooled analysis of two studies showed no statistically significant difference in efficacy between Balsalazide 6 g and 3 g/day. Twenty-three per cent of patients in the 6 g/day group relapsed compared to 33% of patients in the 3 g/day group (216 patients; RR 0.76; 95% CI 0.45 to 2.79). One study found Balsalazide 4 g to be superior to 2 g/day. Thirty-seven per cent of patients in the 4 g/day Balsalazide group relapsed compared to 55% of patients in the 2 g/day group (133 patients; RR 0.66; 95% CI 0.45 to 0.97). One study found a statistically significant difference between Salofalk granules 3 g and 1.5 g/day. Twenty-five per cent of patients in the Salofalk 3 g/day group relapsed compared to 39% of patients in the 1.5 g/day group (429 patients; RR 0.65; 95% CI 0.49 to 0.86). Common adverse events included flatulence, abdominal pain, nausea, diarrhea, headache, dyspepsia, and nasopharyngitis. There were no statistically significant differences in the incidence of adverse events between 5-ASA and placebo, 5-ASA and SASP, once daily and conventionally dosed 5-ASA, 5-ASA and comparator 5-ASA formulations and 5-ASA dose ranging studies. The trials that compared 5-ASA and SASP may have been biased in favour of SASP because most trials enrolled patients known to be tolerant to SASP which may have minimized SASP-related adverse events. 5-ASA was superior to placebo for maintenance therapy in ulcerative colitis. However, 5-ASA had a statistically significant therapeutic inferiority relative to SASP. Oral 5-ASA administered once daily is as effective and safe as conventional dosing for maintenance of remission in quiescent ulcerative colitis. There does not appear to be any difference in efficacy or safety between the various formulations of 5-ASA. Patients with extensive ulcerative colitis or with frequent relapses may benefit from a higher dose of maintenance therapy. High dose therapy appears to be as safe as low dose and is not associated with a higher incidence of adverse events.
Geng, Anjing; Wang, Xu; Wu, Lishu; Wang, Fuhua; Wu, Zhichao; Yang, Hui; Chen, Yan; Wen, Dian; Liu, Xiangxiang
2018-08-30
Organoarsenic arsanilic acid (ASA) contamination of paddy soil is a serious but less concerned hazard to agriculture and health of people consuming rice as staple food, for rice is one major pathway of arsenic (As) exposure to human food. To date little research has studied the effect of ASA on biochemical process of rice. Silicon (Si) application is able to reduce the toxicities of heavy metals in numerous plants, but little information about ASA. This work investigated whether and how Si influenced alleviation of ASA toxicity in rice at biochemical level to have a better understanding of defense mechanism by Si against ASA stress. Results showed that ASA reduced rice growth, disturbed protein metabolism, increased lipid peroxidation but decreased the efficiencies of antioxidant activities compared to control plants, more severe in roots than in shoots. The addition of Si in ASA-stressed rice plants noticeably increased growth and development as well as soluble protein contents, but decreased malondialdehyde (MDA) contents in ASA-stressed rice plants, suggesting that Si did have critical roles in ASA detoxification in rice. Furthermore, increased superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities along with elevated glutathione (GSH) and ascorbic acid (AsA) contents implied the active involvement of ROS scavenging and played, at least in part, to Si-mediated alleviation of ASA toxicity in rice, and these changes were related to rice genotypes and tissues. The study provided physio-chemical mechanistic evidence on the beneficial effect of Si on organoarsenic ASA toxicity in rice seedlings. Copyright © 2018. Published by Elsevier Inc.
Matthis, Andrea L; Zhang, Bin; Denson, Lee A; Yacyshyn, Bruce R; Aihara, Eitaro; Montrose, Marshall H
2016-08-01
5-aminosalicylic acid (5-ASA) is a classic anti-inflammatory drug for the treatment of ulcerative colitis. N-acetyltransferase (NAT) enzymes convert 5-ASA to its metabolite N-acetyl-5-ASA, and it is unresolved whether 5-ASA or N-acetyl-5-ASA is the effective therapeutic molecule. We previously demonstrated that colonic production of N-acetyl-5-ASA (NAT activity) is decreased in dextran sulfate sodium-induced colitis. Our hypothesis is that 5-ASA is the therapeutic molecule to improve colitis, with the corollary that altered NAT activity affects drug efficacy. Since varying clinical effectiveness of 5-ASA has been reported, we also ask if NAT activity varies with inflammation in pediatric or adult patients. Acute colonic inflammation was induced in C57BL/6 NAT wild-type (WT) or knockout mice, using 3.5% dextran sulfate sodium (w/v) concurrent with 5-ASA treatment. Adult and pediatric rectosigmoid biopsies were collected from control or patients with ulcerative colitis. Tissue was analyzed for NAT and myeloperoxidase activity. Dextran sulfate sodium-induced colitis was of similar severity in both NAT WT and knockout mice, and NAT activity was significantly decreased in NAT WT mice. In the setting of colitis, 5-ASA significantly restored colon length and decreased myeloperoxidase activity in NAT knockout but not in WT mice. Myeloperoxidase activity negatively correlated with NAT activity in pediatric patients, but correlation was not observed in adult patients. Inflammation decreases NAT activity in the colon of mice and human pediatric patients. Decreased NAT activity enhances the therapeutic effect of 5-ASA in mice. A NAT activity assay could be useful to help predict the efficacy of 5-ASA therapy.
Ben-Horin, Shomron; Andrews, Jane M; Katsanos, Konstantinos H; Rieder, Florian; Steinwurz, Flavio; Karmiris, Konstantinos; Cheon, Jae Hee; Moran, Gordon William; Cesarini, Monica; Stone, Christian D; Schwartz, Doron; Protic, Marijana; Roblin, Xavier; Roda, Giulia; Chen, Min-Hu; Har-Noy, Ofir; Bernstein, Charles N
2017-04-28
To examine treatment decisions of gastroenterologists regarding the choice of prescribing 5-aminosalycilates (5ASA) with corticosteroids (CS) versus corticosteroids alone for patients with active ulcerative colitis (UC). A cross-sectional questionnaire exploring physicians' attitude toward 5ASA + CS combination therapy vs CS alone was developed and validated. The questionnaire was distributed to gastroenterology experts in twelve countries in five continents. Respondents' agreement with stated treatment choices were assessed by standardized Likert scale. Background professional characteristics of respondents were analyzed for correlation with responses. Six hundred and sixty-four questionnaires were distributed and 349 received (52.6% response rate). Of 340 eligible respondents, 221 (65%) would continue 5ASA in a patient hospitalized for intravenous CS treatment due to a moderate-severe UC flare, while 108 (32%) would stop the 5ASA ( P < 0.001), and 11 (3%) are undecided. Similarly, 62% would continue 5ASA in an out-patient starting oral CS. However, only 140/340 (41%) would proactively start 5ASA in a hospitalized patient not receiving 5ASA before admission. Most (94%) physicians consider the safety profile of 5ASA as very good. Only 52% consider them inexpensive, 35% perceive them to be expensive and 12% are undecided. On multi-variable analysis, less years of practice and perception of a plausible additive mechanistic effect of 5ASA + CS were positively associated with the decision to continue 5ASA with CS. Despite the absence of data supporting its benefit, most gastroenterologists endorse combination of 5ASA + CS for patients with active moderate-to-severe UC. Randomized controlled trials are needed to assess if 5ASA confer any benefit for these patients.
Amino acid derivatives of 5-ASA as novel prodrugs for intestinal drug delivery.
Clerici, C; Gentili, G; Boschetti, E; Santucci, C; Aburbeh, A G; Natalini, B; Pellicciari, R; Morelli, A
1994-12-01
In an attempt to obtain site-specific delivery of 5-ASA in the intestinal tract, we have determined the extent of absorption and metabolism of a number of novel 5-ASA derivatives, namely, (N-L-glutamyl)-amino-2-salicylic acid (1), (N-L-aspartyl)-amino-2-salicylic-acid (2), 5-aminosalicyl-L-proline-L-leucine (3), and 5-(N-L-glutamyl)-aminosalicyl-L-proline-L-leucine (4), which are selectively cleaved by intestinal brush border aminopeptidase A and carboxypeptidases. These novel prodrugs, 5-ASA, and sulfasalazine were administered to adult Fisher rats (N = 30) and to animals that had undergone prior colostomy (N = 30). Urine and feces were collected at timed intervals for 48 hr and the metabolites, 5-ASA, and N-acetyl-5-ASA were measured by high-performance liquid chromatography. The absorption and metabolism of all compounds were essentially identical in colostomized and normal animals. 5-ASA exhibited a rapid proximal intestinal absorption as evidenced by the high cumulative urinary excretion (> 65%) and low fecal excretion. Sulfasalazine, as expected, exhibited a lower urinary recovery (< 35%) and higher fecal excretion of 5-ASA and its metabolite. The novel glutamate and aspartate derivatives (1 and 2) behaved similarly to sulfasalazine, while administration of the proline-leucine derivative (3) resulted in urinary and fecal recovery values intermediate with respect to those observed with 5-ASA and sulfasalazine. 5-(N-L-Glutamyl)-aminosalicyl-L-proline-L-leucine yielded the highest fecal recovery of 5-ASA and its N-acetyl derivative, indicating a more efficient delivery to the distal bowel. Amino acid derivatives of 5-ASA appear to be potentially useful prodrugs for the site-specific delivery of 5-ASA to different regions of the intestinal tract.
Serebruany, Victor L; Malinin, Alex I; Ziai, Wendy; Pokov, Alex N; Bhatt, Deepak L; Alberts, Mark J; Hanley, Dan F
2005-10-01
Clopidogrel is widely used in patients after recent ischemic stroke; however, its ability to yield additional antiplatelet protection on top of aspirin has never been explored in a controlled study. To determine whether clopidogrel with aspirin (C+ASA) will produce more potent platelet inhibition than aspirin alone (ASA) in patients after ischemic stroke, we conducted the Plavix Use for Treatment of Stroke trial. Seventy patients after ischemic stroke were randomly assigned to C+ASA or ASA groups. Platelet studies included aggregometry; cartridge-based analyzers; expression of PECAM-1, P-selectin, GP IIb/IIIa (antigen and activity), vitronectin receptor, and formation of platelet-leukocyte microparticles by flow cytometry. Platelet tests were performed at baseline and after 30 days after randomization. There were no deaths, hospitalizations, or serious adverse events. There were no differences in the baseline platelet characteristics between C+ASA and ASA groups, or significant changes in platelet parameters in the ASA group, except diminished collagen-induced aggregation (P=0.001). In contrast, therapy with C+ASA resulted in a significant inhibition of platelet activity assessed by ADP- (P=0.00001) and collagen-induced (P=0.02) aggregation; closure time prolongation (P=0.03), and reduction of platelet activation units with Ultegra (P=0.00001); expression of PECAM-1 (P=0.01), and GP IIb/IIIa activity with PAC-1 (P=0.02) when compared with ASA group. Therapy with C+ASA also resulted in the reduced formation of platelet-leukocyte microparticles (P=0.02). Treatment with C+ASA for 1 month provides significantly greater inhibition of platelet activity than ASA alone in patients after recent ischemic stroke in the frame of the small randomized trial.
Mesalamine modulates intercellular adhesion through inhibition of p-21 activated kinase-1
Khare, Vineeta; Lyakhovich, Alex; Dammann, Kyle; Lang, Michaela; Borgmann, Melanie; Tichy, Boris; Pospisilova, Sarka; Luciani, Gloria; Campregher, Christoph; Evstatiev, Rayko; Pflueger, Maren; Hundsberger, Harald; Gasche, Christoph
2013-01-01
Mesalamine (5-ASA) is widely used for the treatment of ulcerative colitis, a remitting condition characterized by chronic inflammation of the colon. Knowledge about the molecular and cellular targets of 5-ASA is limited and a clear understanding of its activity in intestinal homeostasis and interference with neoplastic progression is lacking. We sought to identify molecular pathways interfered by 5-ASA, using CRC cell lines with different genetic background. Microarray was performed for gene expression profile of 5-ASA-treated and untreated cells (HCT116 and HT29). Filtering and analysis of data identified three oncogenic pathways interfered by 5-ASA: MAPK/ERK pathway, cell adhesion and β-catenin/Wnt signaling. PAK1 emerged as a consensus target of 5-ASA, orchestrating these pathways. We further investigated the effect of 5-ASA on cell adhesion. 5-ASA increased cell adhesion which was measured by cell adhesion assay and transcellular-resistance measurement. Moreover, 5-ASA treatment restored membranous expression of adhesion molecules E-cadherin and β-catenin. Role of PAK1 as a mediator of mesalamine activity was validated in vitro and in vivo. Inhibition of PAK1 by RNA interference also increased cell adhesion. PAK1 expression was elevated in APCmin polyps and 5-ASA treatment reduced its expression. Our data demonstrates novel pharmacological mechanism of mesalamine in modulation of cell adhesion and role of PAK1 in APCmin polyposis. We propose that inhibition of PAK1 expression by 5-ASA can impede with neoplastic progression in colorectal carcinogenesis. The mechanism of PAK1 inhibition and induction of membranous translocation of adhesion proteins by 5-ASA might be independent of its known anti-inflammatory action. PMID:23146664
Mesalamine modulates intercellular adhesion through inhibition of p-21 activated kinase-1.
Khare, Vineeta; Lyakhovich, Alex; Dammann, Kyle; Lang, Michaela; Borgmann, Melanie; Tichy, Boris; Pospisilova, Sarka; Luciani, Gloria; Campregher, Christoph; Evstatiev, Rayko; Pflueger, Maren; Hundsberger, Harald; Gasche, Christoph
2013-01-15
Mesalamine (5-ASA) is widely used for the treatment of ulcerative colitis, a remitting condition characterized by chronic inflammation of the colon. Knowledge about the molecular and cellular targets of 5-ASA is limited and a clear understanding of its activity in intestinal homeostasis and interference with neoplastic progression is lacking. We sought to identify molecular pathways interfered by 5-ASA, using CRC cell lines with different genetic background. Microarray was performed for gene expression profile of 5-ASA-treated and untreated cells (HCT116 and HT29). Filtering and analysis of data identified three oncogenic pathways interfered by 5-ASA: MAPK/ERK pathway, cell adhesion and β-catenin/Wnt signaling. PAK1 emerged as a consensus target of 5-ASA, orchestrating these pathways. We further investigated the effect of 5-ASA on cell adhesion. 5-ASA increased cell adhesion which was measured by cell adhesion assay and transcellular-resistance measurement. Moreover, 5-ASA treatment restored membranous expression of adhesion molecules E-cadherin and β-catenin. Role of PAK1 as a mediator of mesalamine activity was validated in vitro and in vivo. Inhibition of PAK1 by RNA interference also increased cell adhesion. PAK1 expression was elevated in APC(min) polyps and 5-ASA treatment reduced its expression. Our data demonstrates novel pharmacological mechanism of mesalamine in modulation of cell adhesion and role of PAK1 in APC(min) polyposis. We propose that inhibition of PAK1 expression by 5-ASA can impede with neoplastic progression in colorectal carcinogenesis. The mechanism of PAK1 inhibition and induction of membranous translocation of adhesion proteins by 5-ASA might be independent of its known anti-inflammatory action. Copyright © 2012 Elsevier Inc. All rights reserved.
Emami, Niloufar Hedayati; Lafout, Farzaneh Mahmoudi; Mohammadghasemi, Fahimeh
2018-01-01
Objective(s): Melatonin, an important hormone secreted by the epiphysis, is a powerful anti-oxidant with a high potential to neutralize medical toxins. The goal of this study was to demonstrate the beneficial effect of melatonin on epididymal sperm and reproductive parameters in mice treated with acetylsalicylic acid (ASA). Materials and Methods: Male adult mice were divided into four treatment groups: control, ASA, melatonin, and ASA+melatonin. Mice were administered ASA (50 mg/kg, orally) and/or melatonin (10 mg/kg, intraperitoneally), or vehicle control, for 14 days. Sperm count, sperm motility, and sperm morphology were evaluated to assess fertility. A colorimetric assay was used to measure serum total antioxidant capacity (TAC). A sperm chromatin dispersion (SCD) test was used to assess sperm chromatin integrity. Sex hormone levels were measured by ELISA. Results: Compared to the control group, ASA treatment resulted in a significant decrease in sperm parameters (P<0.05), as well as a decrease in the integrity of sperm chromatin (P<0.01). ASA treatment also reduced serum testosterone and TAC levels (P<0.05). Co-administration of melatonin with ASA significantly improved epididymal sperm parameters and increased serum testosterone and TAC levels compared to the ASA-treated group. LH level was not different in the combined treatment group compared to control or ASA treatment. Conclusion: Short-term administration of ASA (50 mg/kg) has adverse effects on male reproductive function in mice. Co-administration of melatonin protects against ASA-induced impairment of male reproductive function by preventing the reduction in serum TAC and testosterone levels seen with ASA treatment alone. PMID:29456808
A spectroscopic study of phenylbutazone and aspirin bound to serum albumin in rheumatoid diseases
NASA Astrophysics Data System (ADS)
Maciążek-Jurczyk, M.; Sułkowska, A.; Bojko, B.; Równicka-Zubik, J.; Sułkowski, W. W.
2011-11-01
Interaction of phenylbutazone (PBZ) and aspirin (ASA), two drugs recommended in rheumatoid diseases (RDs), when binding to human (HSA) and bovine (BSA) serum albumins, has been studied by quenching of fluorescence and proton nuclear magnetic resonance ( 1HNMR) techniques. On the basis of spectrofluorescence measurements high affinity binding sites of PBZ and ASA on albumin as well as their interaction within the binding sites were described. A low affinity binding site has been studied by proton nuclear magnetic resonance spectroscopy. Using fluorescence spectroscopy the location of binding site in serum albumin (SA) for PBZ and ASA was found. Association constants Ka were determined for binary (i.e. PBZ-SA and ASA-SA) and ternary complexes (i.e. PBZ-[ASA]-SA and ASA-[PBZ]-SA). PBZ and ASA change the affinity of each other to the binding site in serum albumin (SA). The presence of ASA causes the increase of association constants KaI of PBZ-SA complex. Similarly, PBZ influences KaI of ASA-SA complex. This phenomenon shows that the strength of binding and the stability of the complexes increase in the presence of the second drug. The decrease of KaII values suggests that the competition between PBZ and ASA in binding to serum albumin in the second class of binding sites occurs. The analysis of 1HNMR spectral parameters i.e. changes of chemical shifts and relaxation times of the drug indicate that the presence of ASA weakens the interaction of PBZ with albumin. Similarly PBZ weakens the interaction of ASA with albumin. This conclusion points to the necessity of using a monitoring therapy owning to the possible increase of uncontrolled toxic effects.
Ouyang, Nengtai; Williams, Jennie L.; Rigas, Basil
2008-01-01
The inhibitory effect of NO-donating aspirin (NO-ASA) on colon cancer has been demonstrated in vivo and in vitro but its mechanism is still obscure. We investigated the effect of NO-ASA on angiogenesis. Four groups of athymic mice (N = 12) bearing subcutaneous xenotransplants of HT-29 human colon cancer cells were injected intratumorally twice a week for 3 weeks with vehicle or m-NO-ASA or p-NO-ASA; the fourth group received no injections. The necrotic area of tumors, expressed as percentage of total area, was similar in the non-injected and vehicle-injected groups (51.8 ± 2.8 versus 52.2 ± 4.1, P > 0.05; mean ± SEM for these and subsequent values). Compared with the vehicle group, the necrotic area of tumors was higher in the m-NO-ASA-treated (61.0 ± 2.7, P < 0.02) and p-NO-ASA (65.8 ± 2.4, P < 0.001)-treated groups. NO-ASA decreased microvessel density: vehicle = 11.7 ± 0.8; m-NO-ASA = 7.8 ± 0.6 (P = 0.0003 versus vehicle) and p-NO-ASA 6.2 ± 0.7 (P = 0.0001 versus vehicle). The expression of vascular endothelial growth factor (VEGF) was significantly reduced in response to NO-ASA, with the p- isomer being more potent than the m-. NO-ASA altered the spatial distribution of VGEF expression, with 16.7% of the vehicle-treated xenografts displaying diminished VEGF in the inner region of the area between necrosis and the outer perimeter of the tumor, compared with those treated with m- (58.3%) or p-NO-ASA (75%, P < 0.01 for both versus control). Our findings indicate that NO-ASA suppresses the expression of VEGF, which leads to suppressed angiogenesis. The antiangiogenic activity of NO-ASA may be part of its antineoplastic effect. PMID:18544566
The influence of ascorbic acid on root growth and the root apical meristem in Arabidopsis thaliana.
Kka, Noura; Rookes, James; Cahill, David
2018-06-08
Cell division is a fundamental biological process governed by molecular networks that are initiated in the apical meristems of plants. l-ascorbic acid (AsA) commonly known as vitamin C is a crucial molecular modulator involved in cell proliferation. In this study, we used AsA application to Arabidopsis and four AsA pathway mutants to investigate the influence of AsA on the root apical meristem (RAM) and root growth. Treatment of seeds of wild-type Col-0 with AsA prior to sowing showed a significant increase in the activity of cell division of the RAM, root growth rate and root length when compared with untreated seeds. Seedlings of the AsA pathway mutant vtc1-1 showed a significant reduction in the level of AsA and a significant increase in the number of quiescent cells in the RAM when compared with Col-0. Cell proliferation was reduced in the AsA pathway mutants vtc1-1, dhar1, vtc5-1, apx1, respectively, however, root growth decreased significantly only in vtc1-1 when compared with Col-0. In addition, hydrogen peroxide (H 2 O 2 ) levels were shown to increase in the AsA pathway mutants, with the highest level of H 2 O 2 found in vtc1-1. AsA is also shown to have an indirect influence in inducing periclinal division as a reduced level was found in vtc1-1. Therefore, in this study, we found that AsA had an influence on cell proliferation and root growth and VTC1 was shown to be a key modulator of H 2 O 2 levels. These findings open the door for further studies to reveal the involvement of AsA in cell proliferation and the interaction between AsA and H 2 O 2 on cell polarity in the RAM and potentially the shoot apical meristem. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Geometrical-optics approximation of forward scattering by gradient-index spheres.
Li, Xiangzhen; Han, Xiang'e; Li, Renxian; Jiang, Huifen
2007-08-01
By means of geometrical optics we present an approximation method for acceleration of the computation of the scattering intensity distribution within a forward angular range (0-60 degrees ) for gradient-index spheres illuminated by a plane wave. The incident angle of reflected light is determined by the scattering angle, thus improving the approximation accuracy. The scattering angle and the optical path length are numerically integrated by a general-purpose integrator. With some special index models, the scattering angle and the optical path length can be expressed by a unique function and the calculation is faster. This method is proved effective for transparent particles with size parameters greater than 50. It fails to give good approximation results at scattering angles whose refractive rays are in the backward direction. For different index models, the geometrical-optics approximation is effective only for forward angles, typically those less than 60 degrees or when the refractive-index difference of a particle is less than a certain value.
Kuza, Catherine M; Hatzakis, George; Nahmias, Jeffry T
2017-12-01
The American Society of Anesthesiologists (ASA) physical status (PS) classification system assesses the preoperative health of patients. Previous studies demonstrated poor interrater reliability and variable ASA PS scores, especially in trauma scenarios. There are few studies that evaluated the assignment of ASA PS scores in trauma patients and no studies that evaluated ASA PS assignment in severely injured adult polytrauma patients. Our objective was to assess interrater reliability and identify sources of discrepancy among anesthesiologists and trauma surgeons in designating ASA PS scores to adult polytrauma patients. A link to an online survey containing questions assessing attitudes regarding ASA PS classification, demographic information, and 8 fictional trauma cases was e-mailed to anesthesiologists and trauma surgeons. The participants were asked to assign an ASA PS score to each scenario and explain their choice. Rater-versus-reference and interrater reliability, beyond that expected by chance, among respondents was analyzed using the Fleiss kappa analysis. A total of 349 participants completed the survey. All 8 cases had inconsistent ASA PS scores; several cases had scores ranging from I to VI and variable emergency (E) designations. Using weighted kappa (Kw) analysis for a subset of 201 respondents (101 trauma surgeons [S] and 100 anesthesiologists [A]), we found moderate (Kw = 0.63; SE = 0.024; 95% confidence interval, 0.594-0.666; P < .001) interrater-versus-reference reliability. The interrater reliability was fair (Kw = 0.43; SE = 0.037; 95% confidence interval, 0.360-0.491; P < .001). This study demonstrates fair interrater reliability beyond that expected by chance of the ASA PS scores among anesthesiologists and trauma surgeons when assessing adult polytrauma patients. Although the ASA PS is used in some trauma risk stratification models, discrepancies of ASA PS scores assigned to trauma cases exist. Future modifications of the ASA PS guidelines should aim to improve the interrater reliability of ASA PS scores in trauma patients. Further studies are warranted to determine the value of the ASA PS score as a trauma prognostic metric.
Veselka, Josef; Jensen, Morten Kvistholm; Liebregts, Max; Januska, Jaroslav; Krejci, Jan; Bartel, Thomas; Dabrowski, Maciej; Hansen, Peter Riis; Almaas, Vibeke Marie; Seggewiss, Hubert; Horstkotte, Dieter; Tomasov, Pavol; Adlova, Radka; Bundgaard, Henning; Steggerda, Robbert; Ten Berg, Jurriën; Faber, Lothar
2016-05-14
The first cases of alcohol septal ablation (ASA) for obstructive hypertrophic cardiomyopathy (HCM) were published two decades ago. Although the outcomes of single-centre and national ASA registries have been published, the long-term survival and clinical outcome of the procedure are still debated. We report long-term outcomes from the as yet largest multinational ASA registry (the Euro-ASA registry). A total of 1275 (58 ± 14 years, median follow-up 5.7 years) highly symptomatic patients treated with ASA were included. The 30-day post-ASA mortality was 1%. Overall, 171 (13%) patients died during follow-up, corresponding to a post-ASA all-cause mortality rate of 2.42 deaths per 100 patient-years. Survival rates at 1, 5, and 10 years after ASA were 98% (95% CI 96-98%), 89% (95% CI 87-91%), and 77% (95% CI 73-80%), respectively. In multivariable analysis, independent predictors of all-cause mortality were age at ASA (P < 0.01), septum thickness before ASA (P < 0.01), NYHA class before ASA (P = 0.047), and the left ventricular (LV) outflow tract gradient at the last clinical check-up (P = 0.048). Alcohol septal ablation reduced the LV outflow tract gradient from 67 ± 36 to 16 ± 21 mmHg (P < 0.01) and NYHA class from 2.9 ± 0.5 to 1.6 ± 0.7 (P < 0.01). At the last check-up, 89% of patients reported dyspnoea of NYHA class ≤2, which was independently associated with LV outflow tract gradient (P < 0.01). The Euro-ASA registry demonstrated low peri-procedural and long-term mortality after ASA. This intervention provided durable relief of symptoms and a reduction of LV outflow tract obstruction in selected and highly symptomatic patients with obstructive HCM. As the post-procedural obstruction seems to be associated with both worse functional status and prognosis, optimal therapy should be focused on the elimination of LV outflow tract gradient. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.
Korosec, Peter; Tisler, Ursa; Bajrovic, Nissera; Silar, Mira; Mrhar, Ales; Kosnik, Mitja
2011-10-01
Exposure to acetylsalicylic acid (ASA) may exacerbate respiratory or skin diseases or induce anaphylactoid reactions in apparently healthy individuals. We wanted to evaluate the clinical and diagnostic utility of measuring ASA-induced 15-hydroxyeicosatetraenoic acid (15-HETE) generation. We performed a prospective single-blind study with 26 subjects undergoing clinical evaluation and/or ASA provocation testing. We also included 12 control subjects. Peripheral blood leukocytes were incubated with 500 μM ASA and 15-HETE release was measured by competitive ELISA. We found that 18 subjects were ASA-tolerant and 8 were ASA-intolerant. The mean increase in 15-HETE in intolerant subjects was 34% and this was comparable to the mean increase of 30% observed in ASA-tolerant subjects. A similar mean increase was also observed in control subjects. The ROC calculation showed that the optimal diagnostic threshold would be an increase of greater than 33%. However, the sensitivity of this increase was only 63% and the specificity was 50%. Our data suggest that further studies are needed before the ASA-induced 15-HETE test can be used in clinical practice. Copyright © 2011 Elsevier Ltd. All rights reserved.
Combustion of a Polymer (PMMA) Sphere in Microgravity
NASA Technical Reports Server (NTRS)
Yang, Jiann C.; Hamins, Anthony; Donnelly, Michelle K.
1999-01-01
A series of low gravity, aircraft-based, experiments was conducted to investigate the combustion of supported thermoplastic polymer spheres under varying ambient conditions. The three types of thermoplastic investigated were polymethylmethacrylate (PMMA), polypropylene (PP). and polystyrene (PS). Spheres with diameters ranging from 2 mm to 6.35 mm were tested. The total initial pressure varied from 0.05 MPa to 0. 15 MPa whereas the ambient oxygen concentration varied from 19 % to 30 % (by volume). The ignition system consisted of a pair of retractable energized coils. Two CCD cameras recorded the burning histories of the spheres. The video sequences revealed a number of dynamic events including bubbling and sputtering, as well as soot shell formation and break-up during combustion of the spheres at reduced gravity. The ejection of combusting material from the burning spheres represents a fire hazard that must be considered at reduced gravity. The ejection process was found to be sensitive to polymer type. All average burning rates were measured to increase with initial sphere diameter and oxygen concentration, whereas the initial pressure had little effect. The three thermoplastic types exhibited different burning characteristics. For the same initial conditions, the burning rate of PP was slower than PMMA, whereas the burning rate of PS was comparable to PMMA. The transient diameter of the burning thermoplastic exhibited two distinct periods: an initial period (enduring approximately half of the total burn duration) when the diameter remained approximately constant, and a final period when the square of the diameter linearly decreased with time. A simple homogeneous two-phase model was developed to understand the changing diameter of the burning sphere. Its value is based on a competition between diameter reduction due to mass loss from burning and sputtering, and diameter expansion due to the processes of swelling (density decrease with heating) and bubble growth. The model relies on empirical parameters for input, such as the burning rate and the duration of the initial and final burning periods.
Rolland, B; Fovet, T; Poissy, J; Eichholtzer, C; Lesage, M; Thomas, P; Jourdain, M
2018-04-01
Acute states of agitation (ASAs) are frequent in daily medical practice. However, training on real ASAs raises technical and ethical issues, whereas lecture-based teaching hardly addresses some educational objectives, e.g., improving relational skills and team-based coordination. Simulation-based medical education (SBME) is a promising medium to train students on managing ASAs. We have recently implemented a role-playing training module on ASAs. In this scenario, four to five students play the role of the staff, while a trained professional actor plays the agitated patient. A subsequent standardized debriefing is conducted by a senior psychiatrist. A first wave of 219 students participated in a one-session training of this ASA module in June 2015. They completed pre-session and post-session questionnaires aiming to collect "proof-of-concept" data. The pre-session questionnaire investigated: previous experience of ASA among students during their clinical training; previous participation in a role-playing SBME; and perceived knowledge of the good practice rules for managing ASAs. The post-session questionnaire investigated among the students if: they thought having been able to appropriately manage the simulated ASA; they found the SBME medium more fitted for training than real situations; they found that the SBME session faithfully reproduced a real ASA; and the session was found useful for transmitting the skills on correct management of ASA. The average level of stress induced by the training was assessed using a numerical rating scale (0-10). Two hundred and six of the 219 students completed the pre-session questionnaire (63% females; response rate 96.7%). A hundred and thirty four students played the scenario and completed the post-session questionnaire (65.7% females; response rate 100%). 38.3% of the responders reported having previously experienced a situation of ASA in their practice, and 31.1% deemed to know the good practices rules for managing an ASA. In post-session, 29.9% of the participants considered that they appropriately managed the ASA, 79.9% deemed that the role-playing session faithfully reproduced a real ASA, and 97% deemed that this SBME was more fitted and useful than a real clinical situation to improve their medical skills. Bivariate analyses revealed that the post-session responses and level of stress were not influenced by previous experience on ASA, previous participation in a SBME role-playing session, or thinking to know the rules for managing ASAs. SBME role-playing training appears a promising, realistic, and well-accepted method for teaching the management of ASA. Copyright © 2017 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.
A kinetic theory description of the viscosity of dense fluids consisting of chain molecules.
de Wijn, Astrid S; Vesovic, Velisa; Jackson, George; Trusler, J P Martin
2008-05-28
An expression for the viscosity of a dense fluid is presented that includes the effect of molecular shape. The molecules of the fluid are approximated by chains of equal-sized, tangentially jointed, rigid spheres. It is assumed that the collision dynamics in such a fluid can be approximated by instantaneous collisions between two rigid spheres belonging to different chains. The approach is thus analogous to that of Enskog for a fluid consisting of rigid spheres. The description is developed in terms of two molecular parameters, the diameter sigma of the spherical segment and the chain length (number of segments) m. It is demonstrated that an analysis of viscosity data of a particular pure fluid alone cannot be used to obtain independently effective values of both sigma and m. Nevertheless, the chain lengths of n-alkanes are determined by assuming that the diameter of each rigid sphere making up the chain can be represented by the diameter of a methane molecule. The effective chain lengths of n-alkanes are found to increase linearly with the number C of carbon atoms present. The dependence can be approximated by a simple relationship m=1+(C-1)3. The same relationship was reported within the context of a statistical associating fluid theory equation of state treatment of the fluid, indicating that both the equilibrium thermodynamic properties and viscosity yield the same value for the chain lengths of n-alkanes.
Kimiagar, Itzhak; Kalmanovich-Avnery, Shani; Gonen, Ofer M; Sacagiu, Zvika; Shevtzov, Evelina; Levite, Ronen; Weinstein, Jochay; Bartal, Avigail; Aroesty, Rina; Bhonkar, Sarah; Tal, Sigal; Leonov, Youval; Blatt, Alex; Haitov, Zoya; Bar-Hayim, Samuel; Armon, Carmel
2016-10-15
Use of TPA to treat patients with acute ischemic stroke was introduced in Assaf Harofeh Medical Center (AHMC) in Israel in November 2007 initially with strict adherence to the inclusion/exclusion criteria of the pivotal NINDS TPA studies published in 1995. The treatment window was expanded in 2010 to 4.5h following the results of ECASS-III. Application of the 2013 AHA/ASA Guidelines resulted in further expanded inclusion and relaxed exclusion criteria. A retrospective chart review was conducted of patients who received TPA at AHMC to evaluate the additional impact of applying the 2013 guidelines. Number of patients treated, outcomes at discharge, and safety were compared between two periods: May 2011-January 2013 (the 21months preceding the 2013 Guidelines); and February 2013-October 2014 (the 21months after publication of the 2013 Guidelines). Statistical analysis was done using z-tests for differences between proportions, and t-tests to compare means. 63 patients were treated during the immediate pre-2013 Guideline period (36/year, or approximately 5% of patients with ischemic stroke), and 105 during the post-2013 Guidelines period (60/year, approximately 8.3% of patients with ischemic stroke) (p<0.001). During the two periods, respectively: discharges home were 22(34%) and 55(52%) (p<0.05); facility discharges were 29(46%) and 33(31%); and inter-hospital transfers were 6(9%), and 11(10% of treated patients). Most transfers were for endovascular treatment. Total treatment-related symptomatic bleeds in the two periods, respectively, was: 4(6%) and 4(4%), and the number of in-hospital deaths was 6 (9%) and 6 (6%) (unchanged). Application of the 2013 AHA/ASA Guidelines resulted in a 64% increase in the number of acute ischemic stroke patients treated with TPA at AHMC with no worsening of aggregate outcomes and no increase in bleeds or deaths. Copyright © 2016 Elsevier B.V. All rights reserved.
Christian, Eric L; Anderson, Vernon E.; Harris, Michael E
2011-01-01
Quantitative analysis of metal ion-phosphodiester interactions is a significant experimental challenge due to the complexities introduced by inner-sphere, outer-sphere (H-bonding with coordinated water), and electrostatic interactions that are difficult to isolate in solution studies. Here, we provide evidence that inner-sphere, H-bonding and electrostatic interactions between ions and dimethyl phosphate can be deconvoluted through peak fitting in the region of the Raman spectrum for the symmetric stretch of non-bridging phosphate oxygens (νsPO 2-). An approximation of the change in vibrational spectra due to different interaction modes is achieved using ions capable of all or a subset of the three forms of metal ion interaction. Contribution of electrostatic interactions to ion-induced changes to the Raman νsPO2- signal could be modeled by monitoring attenuation of νsPO2- in the presence of tetramethylammonium, while contribution of H-bonding and inner-sphere coordination could be approximated from the intensities of altered νsPO2- vibrational modes created by an interaction with ammonia, monovalent or divalent ions. A model is proposed in which discrete spectroscopic signals for inner-sphere, H-bonding, and electrostatic interactions are sufficient to account for the total observed change in νsPO2- signal due to interaction with a specific ion capable of all three modes of interaction. Importantly, the quantitative results are consistent with relative levels of coordination predicted from absolute electronegativity and absolute hardness of alkali and alkaline earth metals. PMID:21334281
Strong and weak adsorptions of polyelectrolyte chains onto oppositely charged spheres
NASA Astrophysics Data System (ADS)
Cherstvy, A. G.; Winkler, R. G.
2006-08-01
We investigate the complexation of long thin polyelectrolyte (PE) chains with oppositely charged spheres. In the limit of strong adsorption, when strongly charged PE chains adapt a definite wrapped conformation on the sphere surface, we analytically solve the linear Poisson-Boltzmann equation and calculate the electrostatic potential and the energy of the complex. We discuss some biological applications of the obtained results. For weak adsorption, when a flexible weakly charged PE chain is localized next to the sphere in solution, we solve the Edwards equation for PE conformations in the Hulthén potential, which is used as an approximation for the screened Debye-Hückel potential of the sphere. We predict the critical conditions for PE adsorption. We find that the critical sphere charge density exhibits a distinctively different dependence on the Debye screening length than for PE adsorption onto a flat surface. We compare our findings with experimental measurements on complexation of various PEs with oppositely charged colloidal particles. We also present some numerical results of the coupled Poisson-Boltzmann and self-consistent field equation for PE adsorption in an assembly of oppositely charged spheres.
Volumes and surface areas of pendular rings
Rose, W.
1958-01-01
A packing of spheres is taken as a suitable model of porous media. The packing may be regular and the sphere size may be uniform, but in general, both should be random. Approximations are developed to give the volumes and surface areas of pendular rings that exist at points of sphere contact. From these, the total free volume and interfacial specific surface area are derived as expressive of the textural character of the packing. It was found that the log-log plot of volumes and surface areas of pendular rings vary linearly with the angle made by the line joining the sphere centers and the line from the center of the largest sphere to the closest edge of the pendular ring. The relationship, moreover, was found not to be very sensitive to variation in the size ratio of the spheres in contact. It also was found that the addition of pendular ring material to various sphere packings results in an unexpected decrease in the surface area of the boundaries that confine the resulting pore space. ?? 1958 The American Institute of Physics.
Three-Dimensional Visualization of Wave Functions for Rotating Molecule: Plot of Spherical Harmonics
ERIC Educational Resources Information Center
Nagaoka, Shin-ichi; Teramae, Hiroyuki; Nagashima, Umpei
2013-01-01
At an early stage of learning quantum chemistry, undergraduate students usually encounter the concepts of the particle in a box, the harmonic oscillator, and then the particle on a sphere. Rotational levels of a diatomic molecule can be well approximated by the energy levels of the particle on a sphere. Wave functions for the particle in a…
Pore-scale modeling of saturated permeabilities in random sphere packings.
Pan, C; Hilpert, M; Miller, C T
2001-12-01
We use two pore-scale approaches, lattice-Boltzmann (LB) and pore-network modeling, to simulate single-phase flow in simulated sphere packings that vary in porosity and sphere-size distribution. For both modeling approaches, we determine the size of the representative elementary volume with respect to the permeability. Permeabilities obtained by LB modeling agree well with Rumpf and Gupte's experiments in sphere packings for small Reynolds numbers. The LB simulations agree well with the empirical Ergun equation for intermediate but not for small Reynolds numbers. We suggest a modified form of Ergun's equation to describe both low and intermediate Reynolds number flows. The pore-network simulations agree well with predictions from the effective-medium approximation but underestimate the permeability due to the simplified representation of the porous media. Based on LB simulations in packings with log-normal sphere-size distributions, we suggest a permeability relation with respect to the porosity, as well as the mean and standard deviation of the sphere diameter.
ASAS 095221-4329.8 und ASAS 123034-7703.9 - zwei R-CrB-Stern-Kandidaten aus der ASAS-Datenbank
NASA Astrophysics Data System (ADS)
Huemmerich, Stefan
2011-04-01
During an examination of ASAS Misc-type objects, the stars ASAS 095221-4329.8 GSC 07706-00560, 09:52:21.38 -43:29:40.5) and ASAS 123034-7703.9 (GSC 09416-00380, 12:30:34.22 -77:03:52.7) - both of which show semi-regular variability - were found to exhibit significant obscuration events in their V-band lightcurves. Both stars are likely to be red giants undergoing fading events, possibly of DY Per-type. However, spectroscopy of both stars is needed for a conclusive classification. The corresponding entries in the International Variable Star Index (VSX) have been revised accordingly; variability type was set to "RCB:".
NASA Astrophysics Data System (ADS)
Takagi, Hideo D.; Swaddle, Thomas W.
1996-01-01
The outer-sphere contribution to the volume of activation of homogeneous electron exchange reactions is estimated for selected solvents on the basis of the mean spherical approximation (MSA), and the calculated values are compared with those estimated by the Strank-Hush-Marcus (SHM) theory and with activation volumes obtained experimentally for the electron exchange reaction between tris(hexafluoroacetylacetonato)ruthenium(III) and -(II) in acetone, acetonitrile, methanol and chloroform. The MSA treatment, which recognizes the molecular nature of the solvent, does not improve significantly upon the continuous-dielectric SHM theory, which represents the experimental data adequately for the more polar solvents.
Urinalysis of MMX-mesalazine as a tool to monitor 5-ASA adherence in daily IBD practice.
Römkens, Tessa E H; Te Morsche, Rene; Peters, Wilbert; Burger, David M; Hoentjen, Frank; Drenth, Joost P H
2018-03-01
Adherence is pivotal but challenging in ulcerative colitis (UC) treatment. Many methods to assess adherence are subjective or have limitations. (Nac-)5-aminosalicylic acid (5-ASA) urinalysis by high-performance liquid chromatography (HPLC) seems feasible and reproducible in healthy volunteers. We performed a prospective study in adult quiescent UC patients to evaluate the feasibility of spot (Nac-)5-ASA urinalysis by HPLC to assess adherence in daily inflammatory bowel disease (IBD) care. Twenty-nine patients (51.7% male, mean age 52 ± 11 years) were included (median FU 9 months) and weekly spot urine samples were collected. We found large variation in spot (Nac-)5-ASA urinary excretion that was unrelated to brand, dosing schedule or dosage of 5-ASA. In conclusion, spot (Nac-)5-ASA urinalysis is not applicable to assess 5-ASA adherence in daily IBD care. © 2017 The British Pharmacological Society.
Ulcerative proctitis: a review of pharmacotherapy and management.
Lakatos, Peter Laszlo; Lakatos, Laszlo
2008-04-01
Ulcerative proctitis (UP) is a common presentation of ulcerative colitis (UC). To summarize available literature on up-to-date management and pharmacotherapy of UP patients. Extensive Medline/Embase literature search was performed to identify relevant articles. Topical medication with rectally administered 5-aminosalicylic acid (5-ASA)/corticosteroid suppositories or enemas is effective treatment for most UP patients. Locally administered 5-ASA is more efficacious than oral compounds. The combination of topical 5-ASA and oral 5-ASA or topical steroids should be considered for escalation of treatment. Maintenance treatment is indicated in all UC cases. 5-ASA suppositories are suggested as first-line maintenance therapy if accepted by patients, although oral 5-ASA as maintenance therapy might prevent proximal extension of the disease. After re-assessment, chronically active patients refractory or intolerant to 5-ASAs and corticosteroids may require immunomodulators or biological therapy. Exceptional cases may require a proctocolectomy.
Control Aspects of Highly Constrained Guidance Techniques
1978-02-01
cycle. The advantages of this approach are (1) it requires only one time- consuming computation of the platform-to-body transformation matrix from...of steering gain corresponding to the three autopilot configurations, Kchange is KFCS change 2 0.0006 5 0.00156 8 0.00256 2.7 Terminal Steering As...a time- consuming process that it is desirable to consider ways of reducing the com- putation time by approximating the elements of B and/or updating
A Multiple Sphere T-Matrix Fortran Code for Use on Parallel Computer Clusters
NASA Technical Reports Server (NTRS)
Mackowski, D. W.; Mishchenko, M. I.
2011-01-01
A general-purpose Fortran-90 code for calculation of the electromagnetic scattering and absorption properties of multiple sphere clusters is described. The code can calculate the efficiency factors and scattering matrix elements of the cluster for either fixed or random orientation with respect to the incident beam and for plane wave or localized- approximation Gaussian incident fields. In addition, the code can calculate maps of the electric field both interior and exterior to the spheres.The code is written with message passing interface instructions to enable the use on distributed memory compute clusters, and for such platforms the code can make feasible the calculation of absorption, scattering, and general EM characteristics of systems containing several thousand spheres.
Squeeze flow between a sphere and a textured wall
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chastel, T.; Mongruel, A., E-mail: anne.mongruel@upmc.fr
2016-02-15
The motion of a millimetric sphere, translating in a viscous fluid towards a wettable textured wall, is investigated experimentally. The textures consist of square arrays of cylindrical or square micro-pillars, the height, width, and spacing of which are varied, keeping the periodicity small compared to the sphere radius. An interferometric device is used to measure the sphere vertical displacement, for distances between the sphere and the base of the pillars smaller than 0.1 sphere radius, and with a resolution of 200 nm. At a given distance from the top of the pillars, the sphere velocity is found to be significantlymore » larger than the corresponding velocity for a smooth solid wall. A squeeze flow model of two adjacent fluid layers is developed in the lubrication approximation, one fluid layer having an effective viscosity that reflects the viscous dissipation through the array of pillars. The pressure field in the gap between the sphere and the textured surface is then used to obtain the drag force on the sphere and hence its velocity. Adjustment of the model to the velocity measurements yields the effective viscosity for a given texture. Finally, a correlation between the effective viscosity and the geometry of the pillar array is proposed.« less
Variation of ascorbic acid concentration in fruits of cultivated and wild apples.
Fang, Ting; Zhen, Qiaoling; Liao, Liao; Owiti, Albert; Zhao, Li; Korban, Schuyler S; Han, Yuepeng
2017-06-15
Ascorbic acid (AsA) content in mature fruits of 457 apple accessions were measured, and a great variation in AsA concentration was detected. Wild fruits showed significantly higher level of AsA than cultivated fruits. Fruit AsA content was positively correlated with malic acid content, but negatively correlated with fruit weight and soluble solid content. Thus, the difference in AsA content between the wild and cultivated fruits could be attributed to an indirect consequence of human selection for larger fruit size, less acidity, and increased sweetness during apple domestication. Additionally, AsA concentration was extremely high in fruit at the juvenile stage, but dramatically decreased at the expanding and mature stages. The expression levels of three genes controlling AsA accumulation, MdGGP1, MdDHAR3-3, and MdNAT7-2, were significantly negatively correlated with AsA contents in fruits, suggesting a feedback regulation mechanism in AsA-related gene expression. Our results could be helpful for future apple breeding. Copyright © 2017 Elsevier Ltd. All rights reserved.
Hydrocortisone effect of arylsulfatase A in primary mouse brain cell cultures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marcelo, A.; Pieringer, R.A.
The primary goal of this study was to study the mechanism of action of hydrocortisone (HC) on arylsulfatase A (ASA) in primary cultures of cells that were dissociated from the brains of embryonic mice. Cells were cultured in a defined medium in the absence or in the presence of 3 ..mu..M HC. The specific activity of ASA in nontreated cells was 1.297 U/mg (U = ..mu..mol/hr) while the value for the HC-treated cells was 0.783 U/mg. The authors data shows that HC inhibits ASA activity in these cultures cells (p < 0.001). The determination of the ASA enzyme activity wasmore » assayed primarily with the artificial substrate p-nitrocatechol sulfate. However, the natural substrate (cerebroside /sup 35/S-sulfate) also as active and correlated linearly with the activity of p-nitrocatechol sulfate. Purified ASA was isolated from calf brains and used to generate an antibody (Ab) against ASA. The specificity of the Ab for the ASA protein of cell cultures was tested in Ouchterlony double immunodiffusion studies. The Ab was used in a competitive enzyme-linked immunosorbent assay to quantify the number of ASA molecules in the cell extracts from the embryonic mouse cell cultures. Preliminary data suggest that HC decreases the number of ASA molecules.« less
Meals, Clifton; Roy, Siddharth; Medvedev, Gleb; Wallace, Matthew; Neviaser, Robert J; O'Brien, Joseph
2016-01-01
To identify and potentially modify the risk of pulmonary complications in a group of older patients with hip fracture, the authors obtained speech and language pathology consultations for these patients. Then they performed a retrospective chart review of all patients 65 years and older who were admitted to their institution between June 2011 and July 2013 with acute hip fracture, were treated surgically, and had a speech and language pathology evaluation in the immediate perioperative period. The authors identified 52 patients who met the study criteria. According to the American Society of Anesthesiologists (ASA) classification system, at the time of surgery, 1 patient (2%) was classified as ASA I, 12 patients (23%) were ASA II, 26 (50%) were ASA III, and 12 (23%) were ASA IV. Based on a speech and language pathology evaluation, 22 patients (42%) were diagnosed with dysphagia. Statistical analysis showed that ASA III status and ASA IV status were meaningful predictors of dysphagia and that dysphagia itself was a strong risk factor for pulmonary aspiration, pneumonia, and aspiration pneumonitis. Evaluation by a speech and language pathologist, particularly of patients classified as ASA III or ASA IV, may be an efficient means of averting pulmonary morbidity that is common in older patients with hip fracture. Copyright 2016, SLACK Incorporated.
Synthesis of L-ascorbic acid in the phloem
Hancock, Robert D; McRae, Diane; Haupt, Sophie; Viola, Roberto
2003-01-01
Background Although plants are the main source of vitamin C in the human diet, we still have a limited understanding of how plants synthesise L-ascorbic acid (AsA) and what regulates its concentration in different plant tissues. In particular, the enormous variability in the vitamin C content of storage organs from different plants remains unexplained. Possible sources of AsA in plant storage organs include in situ synthesis and long-distance transport of AsA synthesised in other tissues via the phloem. In this paper we examine a third possibility, that of synthesis within the phloem. Results We provide evidence for the presence of AsA in the phloem sap of a wide range of crop species using aphid stylectomy and histochemical approaches. The activity of almost all the enzymes of the primary AsA biosynthetic pathway were detected in phloem-rich vascular exudates from Cucurbita pepo fruits and AsA biosynthesis was demonstrated in isolated phloem strands from Apium graveolens petioles incubated with a range of precursors (D-glucose, D-mannose, L-galactose and L-galactono-1,4-lactone). Phloem uptake of D-[U-14C]mannose and L-[1-14C]galactose (intermediates of the AsA biosynthetic pathway) as well as L-[1-14C]AsA and L-[1-14C]DHA, was observed in Nicotiana benthamiana leaf discs. Conclusions We present the novel finding that active AsA biosynthesis occurs in the phloem. This process must now be considered in the context of mechanisms implicated in whole plant AsA distribution. This work should provoke studies aimed at elucidation of the in vivo substrates for phloem AsA biosynthesis and its contribution to AsA accumulation in plant storage organs. PMID:14633288
Nirogi, Ramakrishna; Kandikere, Vishwottam; Mudigonda, Koteshwara; Ajjala, Devender; Suraneni, Ramakrishna; Thoddi, Parthasarathi
2011-01-01
A simple analytical method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in atmospheric chemical ionization mode (APCI) for the simultaneous estimation of acetylsalicylic acid (ASA, CAS 50-78-2) and its active metabolite salicylic acid (SA, CAS 69-72-7) in human plasma has been developed and validated. ASA and SA were analyzed simultaneously despite differences in plasma concentration ranges of ASA and SA after oral administration of ASA. In spite of having different chemical, ionization and chromatographic properties, ASA and SA were extracted simultaneously from the plasma sample using acetonitrile protein precipitation followed by liquid-liquid extraction. The analytes were separated on a reversed phase column with rapid gradient program using mobile phase consisting of ammonium acetate buffer and methanol. The structural analogue diclofenac was used as an internal standard. The multiple reaction monitoring (MRM) transitions m/z 179 --> 137 for ASA, m/z 137 --> 65 for SA and m/z 294 --> 250 for IS were used. The assay exhibited a linear dynamic range of 0.02-10 microg/mL for ASA and 0.1-50 microg/mL for SA. The between-batch precision (%CV) ranged from 2.1 to 7.9% for ASA and from 0.2 to 5.2% for SA. The between-batch accuracy ranged from 95.4 to 96.7% for ASA and from 94.6 to 111.3% for SA. The validated method was successfully applied for the evaluation of pharmacokinetics of ASA after single oral administration of 650 mg test formulation versus two 325 mg reference formulations of ASA in human subjects.
ASAS definition for sacroiliitis on MRI in SpA: applicable to children?
Herregods, Nele; Dehoorne, Joke; Van den Bosch, Filip; Jaremko, Jacob Lester; Van Vlaenderen, Joke; Joos, Rik; Baraliakos, Xenofon; Varkas, Gaëlle; Verstraete, Koenraad; Elewaut, Dirk; Jans, Lennart
2017-04-11
The Assessment of Spondyloarthritis International Society (ASAS) definition for a 'positive' Magnetic Resonance Imaging (MRI) for sacroiliitis is well studied and validated in adults, but studies about the value of this definition in children are lacking. The aim of this study is to evaluate whether the adult ASAS definition of a positive MRI of the sacroiliac joints can be applied to children with a clinical suspicion of Juvenile Spondyloarthritis (JSpA). Two pediatric musculoskeletal radiologists blinded to clinical data independently retrospectively reviewed sacroiliac (SI) joint MRI in 109 children suspected of sacroiliitis. They recorded global impression (sacroiliitis yes/no) and whether the adult ASAS definition for sacroiliitis was met at each joint. This was compared to gold-standard clinical diagnosis of JSpA. Additionally, MRI were scored according to'adapted' ASAS definitions including other features of sacroiliitis on MRI. JSpA was diagnosed clinically in 47/109 (43%) patients. On MRI, sacroiliitis was diagnosed by global assessment in 30/109 patients, of whom 14 also fulfilled ASAS criteria. No patients with negative global assessment for sacroiliitis fulfilled ASAS criteria. Sensitivity (SN) for JSpA was higher for global assessment (SN = 49%) than for ASAS definition (SN = 26%), but the ASAS definition was more specific (SP = 97% vs. 89%). Modifying adult ASAS criteria to allow bone marrow edema (BME) lesions seen on only one slice, synovitis or capsulitis, increased SN to 36%, 32% and 32% respectively, only slightly lowering SP. Including structural lesions increased SN to 28%, but lowered specificity to 95%. The adult ASAS definition for sacroiliitis has low sensitivity in children. A pediatric-specific definition of MRI-positive sacroiliitis including BME lesions visible on one slice only, synovitis and/or capsulitis may improve diagnostic utility, and increase relevance of MRI in pediatric rheumatology practice.
Boult, Margaret; Cowled, Prue; Barnes, Mary; Fitridge, Robert A
2017-09-01
Although the American Society of Anesthesiologists (ASA) grade was established for statistical purposes, it is often used prognostically. However, older patients undergoing elective surgery are typically ASA III, which limits patient stratification. We look at the prognostic effect on early complications and survival of using ASA and self-reported physical fitness to stratify patients undergoing endovascular repair of abdominal aortic aneurysms. Data were extracted from a trial database. All patients were assigned a fitness level (A (fit) or B (unfit)) based on their self-reported ability to walk briskly for 1 km or climb two flights of stairs. Fitness was used to stratify ASA III patients, with fitter patients assigned ASA IIIA and less fit patients ASA IIIB. Outcomes assessed included survival, reinterventions, endoleak, all early and late complications and early operative complications. A combined ASA/fitness scale (II, IIIA, IIIB and IV) correlated with 1- and 3-year survival (1-year P = 0.001, 3-year P = 0.001) and early and late complications (P = 0.001 and P = 0.05). On its own, ASA predicted early complications (P = 0.0004) and survival (1-year P = 0.01, 3-year P = 0.01). Fitness alone was predictive for survival (1-year P = 0.001, 3-year P = 0.001) and late complications (P = 0.009). This study shows that even a superficial assessment of fitness is reflected in surgical outcomes, with fitter ASA III patients showing survival patterns similar to ASA II patients. Physicians should be alert to differences in fitness between patients in the ASA III group, despite similarities based on preexisting severe systemic disease. © 2017 Royal Australasian College of Surgeons.
Serebruany, Victor L; Malinin, Alex I; Pokov, Alex; Barsness, Gregory; Hanley, Dan F
2008-01-01
Clopidogrel is widely used in diabetic patients after vascular events; however, the ability of this thienopyridine to yield additional antiplatelet protection on top of aspirin has never been explored in a controlled study with comprehensive assessment of platelet activity. The objective of this study was to compare the antiplatelet profiles of clopidogrel + aspirin in combination (C + ASA) versus aspirin alone (ASA) in patients with type 2 diabetes mellitus. Seventy patients with documented diabetes already treated with antecedent aspirin were randomly assigned to receive C + ASA or ASA in the PLUTO-Diabetes trial. Platelet studies included adenosine diphosphate-, collagen-, and arachidonic acid-induced aggregometry; PFA-100 (Dade-Behring, Miami, FL) and Ultegra (Accumetrics, San Diego, CA) analyzers; and expression of 6 major receptors by flow cytometry at baseline and at day 30 after randomization. There were no differences in the baseline clinical and platelet characteristics between the C + ASA and ASA groups, or subsequent significant changes in platelet biomarkers in the ASA group, except for diminished collagen-induced aggregation (P = .02). In contrast, when compared with the ASA group, therapy with C + ASA resulted in significant inhibition of platelet activity assessed by adenosine diphosphate aggregation (P = .0001); closure time prolongation (P = .0003) and reduction of platelet activation units with Ultegra (P = .0001); and expression of platelet/endothelial cell adhesion molecule 1 (P = .002), glycoprotein IIb/IIIa antigen (P = .0002), and activity (P = .0001). Treatment with C + ASA for 1 month provides significantly greater inhibition of platelet activity than ASA alone in diabetic patients in this small randomized trial. However, despite dual antiplatelet regimen, diabetic patients exhibit high residual activity of some platelet biomarkers, including unaffected protease-activated receptor 1 receptor expression.
Matsuzawa, S; Hoshina, K; Sueyoshi, S; Miyata, Y; Manita, S; Ooie, T; Yasue, T; Sasahara, T
2012-12-01
A combination of low-dose aspirin (ASA) and a phosphodiesterase inhibitor has been clinically tried for the secondary prevention of atherothrombotic diseases. The in vivo antithrombotic property of ibudilast (CAS 50847-11-5), a phosphodiesterase 4 (PDE4) inhibitor, was evaluated in a photochemically-induced guinea pig carotid artery thrombosis model in combination with low-dose ASA. The time required to decrease the carotid artery blood flow to the reading "zero" was defined as the time to occlusion (TTO) of the artery through thrombogenesis. Each independent use of ASA (300 mg/kg, p.o.) and ibudilast (3 and 10 mg/kg, p.o.) significantly prolonged the TTO, and ASA (300 mg/kg) significantly increased bleeding time (BT) and gastric mucosal injury. A selective PDE4 inhibitor rolipram (1 and 5 mg/kg, p.o.) tended to prolong the TTO without extending BT. ASA (100 mg/kg) plus ibudilast (3 mg/kg) and ASA (100 mg/kg) plus rolipram (5 mg/kg) markedly prolonged the TTO compared with each agent alone. Interestingly, ASA (100 mg/kg) plus ibudilast (3 mg/kg) caused a longer TTO than ASA (300 mg/kg) alone, without significant extension of BT and gastric mucosal injury as observed in ASA (300 mg/kg). These results indicate that the combination of low-dose ASA and ibudilast has a more potent antithrombotic effect than ASA alone without increasing bleeding tendency and gastric mucosal injury. The potent in vivo antithrombotic effect of this combination may be brought about by an action that is associated with PDE4 inhibition of ibudilast. © Georg Thieme Verlag KG Stuttgart · New York.
Regulation of L-ascorbic acid content in strawberry fruits
Cruz-Rus, Eduardo; Amaya, Iraida; Sánchez-Sevilla, José F.; Botella, Miguel A.; Valpuesta, Victoriano
2011-01-01
Plants have several L-ascorbic acid (AsA) biosynthetic pathways, but the contribution of each one to the synthesis of AsA varyies between different species, organs, and developmental stages. Strawberry (Fragaria×ananassa) fruits are rich in AsA. The pathway that uses D-galacturonate as the initial substrate is functional in ripe fruits, but the contribution of other pathways to AsA biosynthesis has not been studied. The transcription of genes encoding biosynthetic enzymes such as D-galacturonate reductase (FaGalUR) and myo-inositol oxygenase (FaMIOX), and the AsA recycling enzyme monodehydroascorbate reductase (FaMDHAR) were positively correlated with the increase in AsA during fruit ripening. Fruit storage for 72 h in a cold room reduced the AsA content by 30%. Under an ozone atmosphere, this reduction was 15%. Ozone treatment increased the expression of the FaGalUR, FaMIOX, and L-galactose-1-phosphate phosphatase (FaGIPP) genes, and transcription of the L-galactono-1,4-lactone dehydrogenase (FaGLDH) and FAMDHAR genes was higher in the ozone-stored than in the air-stored fruits. Analysis of AsA content in a segregating population from two strawberry cultivars showed high variability, which did not correlate with the transcription of any of the genes studied. Study of GalUR protein in diverse cultivars of strawberry and different Fragaria species showed that a correlation between GalUR and AsA content was apparent in most cases, but it was not general. Three alleles were identified in strawberry, but any sequence effect on the AsA variability was eliminated by analysis of the allele-specific expression. Taken together, these results indicate that FaGalUR shares the control of AsA levels with other enzymes and regulatory elements in strawberry fruit. PMID:21561953
Murray, F E; Hudson, N; Atherton, J C; Cole, A T; Scheck, F; Hawkey, C J
1996-01-01
Calcium carbasalate is a therapeutically active salicylate which seems to cause less gastroduodenal mucosal damage than aspirin in laboratory animals. This endoscopist-blinded, randomised, cross over trial aimed to compare acute gastric mucosal damage in 20 healthy volunteers treated with acetyl salicylic acid (ASA) (650 mg three times daily) and effervescent calcium carbasalate (ECC) (826.8 mg three times daily) bioequivalent to 650 mg ASA over a five day period. Endoscopy was performed immediately before treatment and on day 5 of each treatment. Serum salicylate, thromboxane B2, and gastric mucosal prostaglandin E2 (PGE2) concentrations were measured after endoscopy. ECC caused fewer gastric mucosal erosions than ASA. The total number of gastric erosions was 23.8 (16.1) in the ASA treated subjects compared with 9.1 (8.7) in ECC treated subjects (p = 0.004). Differences between ASA and ECC were significant for both the gastric antrum and body, and for both haemorrhagic and non-haemorrhagic erosions. The mean gastric body Lanza score for mucosal damage was lower after ECC than ASA (p = 0.003). The visual analogue score for gastric body damage was lower for ECC (16.9 mm (15.9)) than for ASA (32.7 mm (20.8)), p = 0.008. Serum salicylate concentrations were similar after both preparations (ASA: 66 (23) mg/l, versus ECC: 58 (17) mg/l, NS). Serum thromboxane B2 was similarly reduced using both preparations-97.2 (3.5)% inhibition with ASA, 95.2 (5.5)% inhibition with calcium carbasalate (NS). Suppression of gastric mucosal PGE2 synthesis was similar with both preparations (ASA: 83.4 (17.1)%; ECC 84.3 (12.9)%; NS). It is concluded that ECC causes significantly less gastroduodenal mucosal damage than ASA administered at bioequivalent doses as judged by serum salicylate, serum thromboxane, and mucosal PGE2 values. ECC may therefore be a less harmful alternative treatment to plain ASA. PMID:8566836
Kavitha, Chandagirikoppal V.; Agarwal, Chapla; Agarwal, Rajesh; Deep, Gagan
2011-01-01
Malignant gliomas are one of the most devastating and incurable tumors. Sustained excessive angiogenesis by glioma cells is the major reason for their uncontrolled growth and resistance toward conventional therapies resulting in high mortality. Therefore, targeting angiogenesis should be a logical strategy to prevent or control glioma cell growth. Earlier studies have shown that Asiatic Acid (AsA), a pentacyclic triterpenoid, is effective against glioma and other cancer cells; however, its efficacy against angiogenesis remains unknown. In the present study, we examined the anti-angiogenic efficacy of AsA using human umbilical vein endothelial cells (HUVEC) and human brain microvascular endothelial cells (HBMEC). Our results showed that AsA (5–20 µM) inhibits HUVEC growth and induces apoptotic cell death by activating caspases (3 and 9) and modulating the expression of apoptosis regulators Bad, survivin and pAkt-ser473. Further, AsA showed a dose-dependent inhibition of HUVEC migration, invasion and capillary tube formation, and disintegrated preformed capillary network. AsA also inhibited the VEGF-stimulated growth and capillary tube formation by HUVEC and HBMEC. Next, we analyzed the angiogenic potential of conditioned media collected from human glioma LN18 and U87-MG cells treated with either DMSO (control conditioned media, CCM) or AsA 20 µM (AsA20 conditioned media, AsA20CM). CCM from glioma cells significantly enhanced the capillary tube formation in both HUVEC and HBMEC, while capillary tube formation in both endothelial cell lines was greatly compromised in the presence of AsA20CM. Consistent with these results, VEGF expression was lesser in AsA20CM compared to CCM, and indeed AsA strongly inhibited VEGF level (both cellular and secreted) in glioma cells. AsA also showed dose-dependent anti-angiogenic efficacy in Matrigel plug assay, and inhibited the glioma cells potential to attract HUVEC/HBMEC. Overall, the present study clearly showed the strong anti-angiogenic potential of AsA and suggests its usefulness against malignant gliomas. PMID:21826202
Diagnosis of a Poorly Performing Liquid Hydrogen Bulk Storage Sphere
NASA Technical Reports Server (NTRS)
Krenn, Angela G.
2011-01-01
There are two 850,000 gallon Liquid Hydrogen (LH2) storage spheres used to support the Space Shuttle Program; one residing at Launch Pad A and the other at Launch Pad B. The LH2 Sphere at Pad B has had a high boiloff rate since being brought into service in the 1960's. The daily commodity loss was estimated to be approximately double that of the Pad A sphere, and well above the minimum required by the sphere's specification. Additionally, after being re-painted in the late 1990's a "cold spot" appeared on the outer sphere which resulted in a poor paint bond, and mold formation. Thermography was used to characterize the area, and the boiloff rate was continually evaluated. All evidence suggested that the high boiloff rate was caused by an excessive heat leak into the inner sphere due to an insulation void in the annulus. Pad B was recently taken out of Space Shuttle program service which provided a unique opportunity to diagnose the sphere's poor performance. The sphere was drained and inerted, and then opened from the annular relief device on the top where a series of boroscoping operations were accomplished. Boroscoping revealed a large Perlite insulation void in the region of the sphere where the cold spot was apparent. Perlite was then trucked in and off-loaded into the annular void region until the annulus was full. The sphere has not yet been brought back into service.
Ramírez-Alcántara, Verónica
2014-01-01
Pharmacotherapy based on 5-aminosalicylic acid (5-ASA) is a preferred treatment for ulcerative colitis, but variable patient response to this therapy is observed. Inflammation can affect therapeutic outcomes by regulating the expression and activity of drug-metabolizing enzymes; its effect on 5-ASA metabolism by the colonic arylamine N-acetyltransferase (NAT) enzyme isoforms is not firmly established. We examined if inflammation affects the capacity for colonic 5-ASA metabolism and NAT enzyme expression. 5-ASA metabolism by colonic mucosal homogenates was directly measured with a novel fluorimetric rate assay. 5-ASA metabolism reported by the assay was dependent on Ac-CoA, inhibited by alternative NAT substrates (isoniazid, p-aminobenzoylglutamate), and saturable with Km (5-ASA) = 5.8 μM. A mouse model of acute dextran sulfate sodium (DSS) colitis caused pronounced inflammation in central and distal colon, and modest inflammation of proximal colon, defined by myeloperoxidase activity and histology. DSS colitis reduced capacity for 5-ASA metabolism in central and distal colon segments by 52 and 51%, respectively. Use of selective substrates of NAT isoforms to inhibit 5-ASA metabolism suggested that mNAT2 mediated 5-ASA metabolism in normal and colitis conditions. Western blot and real-time RT-PCR identified that proximal and distal mucosa had a decreased mNAT2 protein-to-mRNA ratio after DSS. In conclusion, an acute colonic inflammation impairs the expression and function of mNAT2 enzyme, thereby diminishing the capacity for 5-ASA metabolism by colonic mucosa. PMID:24742986
NASA Astrophysics Data System (ADS)
Bathaie, S. Z.; Nikfarjam, L.; Rahmanpour, R.; Moosavi-Movahedi, A. A.
2010-12-01
Among different biological effects of acetylsalicylic acid (ASA), its anticancer property is controversial. Since ASA hydrolyzes rapidly to salicylic acid (SA), especially in the blood, interaction of both ASA and SA (as the small molecules) with ctDNA, oligo(dA·dT) 15 and oligo(dG·dC) 15, as a possible mechanism of their action, is investigated here. The results show that the rate of ASA hydrolysis in the absence and presence of ctDNA is similar. The spectrophotometric results indicate that both ASA and SA cooperatively bind to ctDNA. The binding constants ( K) are (1.7 ± 0.7) × 10 3 M -1 and (6.7 ± 0.2) × 10 3 M -1 for ASA and SA, respectively. Both ligands quench the fluorescence emission of ethidium bromide (Et)-ctDNA complex. The Scatchard plots indicate the non-displacement based quenching (non-intercalative binding). The circular dichroism (CD) spectra of ASA- or SA-ctDsNA complexes show the minor distortion of ctDNA structure, with no characteristic peaks for intercalation of ligands. Tm of ctDNA is decreased up to 3 °C upon ASA binding. The CD results also indicate more distortions on oligo(dG·dC) 15 structure due to the binding of both ASA and SA in comparison with oligo(dA·dT) 15. All data indicate the more affinity for SA binding with DNA minor groove in comparison with ASA which has more hydrophobic character.
Clough, S; Shehabi, Z; Morgan, C
2016-02-12
Medical risk assessment is essential to safe patient management and the delivery of appropriate dental care. The American Society of Anesthesiologists Physical Status (ASA PS) Classification is widely used within medicine and dentistry, but has received significant criticism. This is the first UK survey to assess the consistency of medical risk assessment in dentistry. (i) To determine the use and consistency of the ASA PS among dentists and anaesthetists. (ii) To consider the appropriateness of the ASA PS in relation to dental treatment planning and delivery of care. A cross-sectional online questionnaire was distributed to anaesthetists and dental practitioners in general practice, community and hospital dental services. Questions focused on professional backgrounds, use of the ASA PS, alternative approaches to risk assessment in everyday practice and scoring of eight hypothetical patients using ASA PS. There were 101 responses, 82 were complete. Anaesthetists recorded ASA PS score more frequently than dental practitioners and found it more useful. Inconsistencies were evident in the assignment of ASA PS scores both between and within professional groups. Many dental practitioners did not use or find ASA PS helpful, with significant inconsistencies in its use. An awareness of alternative assessment scales may be useful across settings. Accepting its limitations, it would be helpful for all dentists to be educated in ASA PS and its use in medical risk assessment, particularly in relation to conscious sedation.
Genetic evidence for the role of GDP-mannose in plant ascorbic acid (vitamin C) biosynthesis
Conklin, Patricia L.; Norris, Susan R.; Wheeler, Glen L.; Williams, Elizabeth H.; Smirnoff, Nicholas; Last, Robert L.
1999-01-01
Vitamin C (l-ascorbic acid; AsA) acts as a potent antioxidant and cellular reductant in plants and animals. AsA has long been known to have many critical physiological roles in plants, yet its biosynthesis is only currently being defined. A pathway for AsA biosynthesis that features GDP-mannose and l-galactose has recently been proposed for plants. We have isolated a collection of AsA-deficient mutants of Arabidopsis thaliana that are valuable tools for testing of an AsA biosynthetic pathway. The best-characterized of these mutants (vtc1) contains ≈25% of wild-type AsA and is defective in AsA biosynthesis. By using a combination of biochemical, molecular, and genetic techniques, we have demonstrated that the VTC1 locus encodes a GDP-mannose pyrophosphorylase (mannose-1-P guanyltransferase). This enzyme provides GDP-mannose, which is used for cell wall carbohydrate biosynthesis and protein glycosylation as well as for AsA biosynthesis. In addition to genetically defining the first locus involved in AsA biosynthesis, this work highlights the power of using traditional mutagenesis techniques coupled with the Arabidopsis Genome Initiative to rapidly clone physiologically important genes. PMID:10097187
Critical Dimensions of Water-tamped Slabs and Spheres of Active Material
DOE R&D Accomplishments Database
Greuling, E.; Argo, H.: Chew, G.; Frankel, M. E.; Konopinski, E.J.; Marvin, C.; Teller, E.
1946-08-06
The magnitude and distribution of the fission rate per unit area produced by three energy groups of moderated neutrons reflected from a water tamper into one side of an infinite slab of active material is calculated approximately in section II. This rate is directly proportional to the current density of fast neutrons from the active material incident on the water tamper. The critical slab thickness is obtained in section III by solving an inhomogeneous transport integral equation for the fast-neutron current density into the tamper. Extensive use is made of the formulae derived in "The Mathematical Development of the End-Point Method" by Frankel and Goldberg. In section IV slight alterations in the theory outlined in sections II and III were made so that one could approximately compute the critical radius of a water-tamper sphere of active material. The derived formulae were applied to calculate the critical dimensions of water-tamped slabs and spheres of solid UF{sub 6} leaving various (25) isotope enrichment fractions. Decl. Dec. 16, 1955.
Shin, Bich Na; Ahn, Ji Hyeon; Kim, In Hye; Lee, Jae-Chul; Yoo, Ki-Yeon; Hwang, In Koo; Choi, Jung Hoon; Park, Jeong Ho; Lee, Yun Lyul; Suh, Hong-Won; Jun, Jong-Gab; Kwon, Young-Guen; Kim, Young-Myeong; Kwon, Seung-Hae; Her, Song; Kim, Jin Su; Hyun, Byung-Hwa; Kim, Chul-Kyu; Cho, Jun Hwi; Lee, Choong Hyun; Won, Moo-Ho
2013-01-01
Stroke is the second leading cause of death. Experimental animal models of cerebral ischemia are widely used for researching mechanisms of ischemic damage and developing new drugs for the prevention and treatment of stroke. The present study aimed to comparatively investigate neuroprotective effects of aspirin (ASA), decursinol (DA) and new synthetic aspirin-decursinol adduct (ASA-DA) against transient focal and global cerebral ischemic damage. We found that treatment with 20 mg/kg, not 10 mg/kg, ASA-DA protected against ischemia-induced neuronal death after transient focal and global ischemic damage, and its neuroprotective effect was much better than that of ASA or DA alone. In addition, 20 mg/kg ASA-DA treatment reduced the ischemia-induced gliosis and maintained antioxidants levels in the corresponding injury regions. In brief, ASA-DA, a new synthetic drug, dramatically protected neurons from ischemic damage, and neuroprotective effects of ASA-DA may be closely related to the attenuation of ischemia-induced gliosis and maintenance of antioxidants. PMID:24073226
Yan, Bing Chun; Park, Joon Ha; Shin, Bich Na; Ahn, Ji Hyeon; Kim, In Hye; Lee, Jae-Chul; Yoo, Ki-Yeon; Hwang, In Koo; Choi, Jung Hoon; Park, Jeong Ho; Lee, Yun Lyul; Suh, Hong-Won; Jun, Jong-Gab; Kwon, Young-Guen; Kim, Young-Myeong; Kwon, Seung-Hae; Her, Song; Kim, Jin Su; Hyun, Byung-Hwa; Kim, Chul-Kyu; Cho, Jun Hwi; Lee, Choong Hyun; Won, Moo-Ho
2013-01-01
Stroke is the second leading cause of death. Experimental animal models of cerebral ischemia are widely used for researching mechanisms of ischemic damage and developing new drugs for the prevention and treatment of stroke. The present study aimed to comparatively investigate neuroprotective effects of aspirin (ASA), decursinol (DA) and new synthetic aspirin-decursinol adduct (ASA-DA) against transient focal and global cerebral ischemic damage. We found that treatment with 20 mg/kg, not 10 mg/kg, ASA-DA protected against ischemia-induced neuronal death after transient focal and global ischemic damage, and its neuroprotective effect was much better than that of ASA or DA alone. In addition, 20 mg/kg ASA-DA treatment reduced the ischemia-induced gliosis and maintained antioxidants levels in the corresponding injury regions. In brief, ASA-DA, a new synthetic drug, dramatically protected neurons from ischemic damage, and neuroprotective effects of ASA-DA may be closely related to the attenuation of ischemia-induced gliosis and maintenance of antioxidants.
Inhibition of cyclooxygenase-independent platelet aggregation by sodium salicylate.
Violi, F; Alessandri, C; Praticò, D; Guzzo, A; Ghiselli, A; Balsano, F
1989-06-15
The effect of acetylsalicylic acid (ASA) on platelet aggregation (PA) and thromboxane A2 (TxA2) formation was investigated in vitro and ex vivo after 1 g or 300 mg ASA administration to healthy subjects. 50-100 microM ASA inhibited PA by single aggregating agent such as platelet aggregating factor (PAF) or epinephrine and reduced to less than or equal to 5% of control platelet TxB2 formation, but did not influence PA by epinephrine plus PAF. The latter was inhibited by increasing ASA concentration. In samples incubated with 100 microM ASA and stimulated with epinephrine plus PAF, PA could be inhibited by the addition of 100-300 microM sodium salicylate. After 300 mg-1 g ASA administration to healthy subjects, the inhibition of PA by epinephrine plus PAF was more marked by highest doses of ASA. This study suggests that aspirin inhibits PA with a cyclooxygenase-independent mechanism; this effect is mediated, at least in vitro, by salicylic acid.
2012-01-01
Background One of the most important biological characteristics of Glioblastoma multiforme (GBM) is high vascular density. Vadimezan (ASA404, DMXAA) belongs to the class of small molecule vascular disrupting agents (VDA) that cause disruption of established tumor vessels and subsequent tumor hemorrhagic necrosis. Its selective antivascular effect is mediated by intratumoral induction of several cytokines including tumor necrosis factor-α (TNF-α), granulocyte-colony-stimulating factor (G-CSF), interleukin 6 (IL-6) and macrophage inflammatory protein 1α (MIP-1α). Preclinical studies have demonstrated that ASA404 acts synergistically with taxanes. In this study, we investigated if treatment of mice bearing U251 human glioblastoma xenografts with ASA404 and taxol may be synergistic. Therapy response was evaluated by measuring changes in tumor size and metabolic activity using 18F-FDG PET (Fluorodeoxyglucose - positron emision tomography) imaging. Methods U251 cells were inoculated s.c. in the right hind limb of NMRI-Foxn1nu athymic female nude mice. Animals were randomly assigned into 4 groups (7–9 animals/group) for treatment: control, taxol, ASA404, and ASA404 plus taxol. The animals received either a single dose of taxol (10 mg/kg), ASA404 (27.5 mg/kg), or taxol (10 mg/kg) plus ASA404 (27.5 mg/kg) administered i.p.; ASA404 was administred 24 h after the treatment with taxol. 4 and 24 h after treatment with ASA404 (28 and 48 h hours after treatment with taxol) 18 F-FDG PET scans were performed. Results The treatment with taxol did not affect the tumor growth in comparison to untreated controls. The treatment of animals with single dose ASA404 alone or in combination with taxol caused a significant delay in tumor growth. The combined treatment did not decrease the growth of the xenografts significantly more than ASA404 alone, but early changes in tumor 18 F-FDG uptake preceded subsequent growth inhibition. The tumor weights, which were determined at the end of treatment, were lower in case of combined treatment. Conclusions The treatment with ASA404 alone or in combination with taxol showed antitumoral effects in our glioblastoma model probably through destruction of blood vessels. The implications for the anticancer effect of this compound warrant further preclinical studies. 18F-FDG PET appears to be a promising tool to monitor treatment with ASA404 early in the course of therapy. PMID:22695475
Bakker, Pauline; Moltó, Anna; Etcheto, Adrien; Van den Bosch, Filip; Landewé, Robert; van Gaalen, Floris; Dougados, Maxime; van der Heijde, Désirée
2017-05-16
In this study, we sought to compare the performance of spondyloarthritis (SpA) classification criteria sets in an international SpA cohort with patients included from five continents around the world. Data from the (ASAS) COMOrbidities in SPondyloArthritis (ASAS-COMOSPA) study were used. ASAS-COMOSPA is a multinational, cross-sectional study with consecutive patients diagnosed with SpA by rheumatologists worldwide. Patients were classified according to the European Spondyloarthropathy Study Group (ESSG), modified European Spondyloarthropathy Study Group (mESSG), Amor, modified Amor, Assessment of SpondyloArthritis international Society (ASAS) axial Spondyloarthritis (axSpA), ASAS peripheral spondyloarthritis (pSpA) and ClASsification criteria for Psoriatic Arthritis (CASPAR) criteria. Overlap between the classification criteria sets was assessed for patients with and without back pain. Furthermore, patients fulfilling different arms of the ASAS axSpA criteria (imaging arm, clinical arm, both arms) were compared on the presence of SpA features. A total of 3942 patients (5 continents, 26 countries) were included. The mean age was 43.6 years, 65.0% were male, 56.2% were human leucocyte antigen B27-positive and 64.4% had radiographic sacroiliitis (based on modified New York criteria). Of the patients, 85.5% were classified by the ASAS SpA criteria (87.7% ASAS axSpA, 12.3% ASAS pSpA). Fulfilment of the Amor, ESSG and CASPAR criteria was present in 83.3%, 88.4% and 21.6% of patients, respectively. Of the patients with back pain (n = 3227), most were classified by all three of Amor, ESSG and ASAS axSpA criteria (71.4%). Patients fulfilling the imaging arm and the clinical arm of the ASAS axSpA criteria had similar presentations of SpA features. In patients without back pain, overlap between classification criteria sets was seen, although to a lesser extent. Most patients with a clinical diagnosis of axial SpA in the worldwide ASAS-COMOSPA study fulfil several classification criteria sets, and a substantial overlap between different criteria sets is seen, which suggests a high level of credibility of the criteria. Large inter-regional differences in the fulfilment of classification criteria were not found. Patients fulfilling the clinical arm were remarkably similar to patients fulfilling the imaging arm with respect to the presence of most SpA features.
Li, Jian-Ping; Guo, Jian-Ming; Shang, Er-Xin; Zhu, Zhen-Hua; Liu, Yang; Zhao, Bu-Chang; Zhao, Jing; Tang, Zhi-Shu; Duan, Jin-Ao
2017-05-10
Acetylsalicylic acid (Aspirin, ASA) is a famous drug for cardiovascular diseases in recent years. Effects of ASA dosage on the metabolic profile have not been fully understood. The purpose of our study is to establish a rapid and reliable method to quantify ASA metabolites in biological matrices, especially for glucuronide metabolites whose standards are not commercially available. Then we applied this method to evaluate the effects of ASA dosage on the metabolic and excretion profile of ASA metabolites in rat urine. Salicylic acid (SA), gentisic acid (GA) and salicyluric acid (SUA) were determined directly by UHPLC-MS/MS, while salicyl phenolic glucuronide (SAPG) and salicyluric acid phenolic glucuronide (SUAPG) were quantified indirectly by measuring the released SA and SUA from SAPG and SUAPG after β-glucuronidase digestion. SUA and SUAPG were the major metabolites of ASA in rat urine 24h after ASA administration, which accounted for 50% (SUA) and 26% (SUAPG). When ASA dosage was increased, the contributions dropped to 32% and 18%, respectively. The excretion of other three metabolites (GA, SA and SAPG) however showed remarkable increases by 16%, 6% and 4%, respectively. In addition, SUA and SUAPG were mainly excreted in the time period of 12-24h, while GA was excreted in the earlier time periods (0-4h and 4-8h). SA was mainly excreted in the time period of 0-4h and 12-24h. And the excretion of SAPG was equally distributed in the four time periods. We went further to show that the excretion of five metabolites in rat urine was delayed when ASA dosage was increased. In conclusion, we have developed a rapid and sensitive method to determine the five ASA metabolites (SA, GA, SUA, SAPG and SUAPG) in rat urine. We showed that ASA dosage could significantly influence the metabolic and excretion profile of ASA metabolites in rat urine. Copyright © 2016 Elsevier B.V. All rights reserved.
Approximate analysis of the formation of a buoyant solid sphere in a supercooled melt
DOE Office of Scientific and Technical Information (OSTI.GOV)
Solomon, A.D.; Wilson, D.G.; Alexiades, V.
1986-03-01
A mathematical model is presented for the idealized formation and development of a buoyant sphere solidifying in an infinite pool of supercooled liquid. The solid and liquid are of the same pure material and the solid is less dense than the liquid. Initially the liquid is at a uniform temperature that is below its equilibrium freezing temperature, T/sub cr/, but above the so called hypercooled temperature, T/sub cr/ - H/c/sub L/. Here H and c/sub L/ are the latent heat of solidification and the specific heat of the liquid, respectively. An approximate solution is derived based on the Megerlin approximationmore » method. 11 refs.« less
Sáez, María E; González-Pérez, Antonio; Johansson, Saga; Himmelmann, Anders; García Rodríguez, Luis A
2016-07-01
In secondary cardiovascular prevention, discontinuation of acetylsalicylic acid (ASA) is associated with an increased risk of cardiovascular events. This study assessed the impact of ASA reinitiation on the risk of myocardial infarction and coronary heart disease death. Patients prescribed ASA for secondary cardiovascular prevention and who had had a period of ASA discontinuation of ≥90 days in 2000-2007 were identified from The Health Improvement Network (N = 10,453). Incidence of myocardial infarction/coronary heart disease death was calculated. Survival analyses using adjusted Cox proportional hazard models were performed to calculate hazard ratios and 95% confidence intervals for the risk of myocardial infarction/coronary heart disease death associated with ASA use patterns after the initial period of discontinuation. Individuals who were prescribed ASA during follow-up were considered reinitiators. The incidence of myocardial infarction/coronary heart disease death was 8.90 cases per 1000 person-years. Risk of myocardial infarction/coronary heart disease death was similar for current ASA users, who had been continuously exposed since reinitiation, and patients who had not reinitiated ASA (hazard ratio 1.27, 95% confidence interval 0.93-1.73). Among reinitiators, an additional period of ASA discontinuation was associated with increased risk of myocardial infarction/coronary heart disease death compared with no reinitiation (current users: hazard ratio 1.46, 95% confidence interval 1.13-1.90; noncurrent users: hazard ratio 1.70, 95% confidence interval 1.31-2.21). ASA reinitiation was not associated with a decreased risk of myocardial infarction/coronary heart disease death. This may be explained by confounding by indication/comorbidity, whereby higher-risk patients are more likely to reinitiate therapy. An additional period of ASA discontinuation among reinitiators was associated with an increased risk of myocardial infarction/coronary heart disease death. © The European Society of Cardiology 2015.
Release of 5-Aminosalicylic Acid (5-ASA) from Mesalamine Formulations at Various pH Levels.
Abinusawa, Adeyinka; Tenjarla, Srini
2015-05-01
Oral formulations of 5-aminosalicylic acid (5-ASA) for treatment of ulcerative colitis have been developed to minimize absorption prior to the drug reaching the colon. In this study, we investigate the release of 5-ASA from available oral mesalamine formulations in physiologically relevant pH conditions. Release of 5-ASA from 6 mesalamine formulations (APRISO®, Salix Pharmaceuticals, Inc., USA; ASACOL® MR, Procter & Gamble Pharmaceuticals UK Ltd.; ASACOL® HD, Procter & Gamble Pharmaceuticals, USA; MEZAVANT XL®, Shire US Inc.; PENTASA®, Ferring Pharmaceuticals, Ltd., UK; SALOFALK®, Dr. Falk Pharma UK Ltd.) was evaluated using United States Pharmacopeia apparatus I and II at pH values of 1.0 (2 h), 6.0 (1 h), and 6.8 (8 h). Dissolution profiles were determined for each formulation, respectively. Of the tested formulations, only the PENTASA formulation demonstrated release of 5-ASA at pH 1.0 (48%), with 56% cumulative release after exposure to pH 6.0 and 92% 5-ASA release after 6-8 h at pH 6.8. No other mesalamine formulation showed >1% drug release at pH 1.0. The APRISO formulation revealed 36% 5-ASA release at pH 6.0, with 100% release after 3 h at pH 6.8. The SALOFALK formulation revealed 11% 5-ASA release at pH 6.0, with 100% release after 1 h at pH 6.8. No 5-ASA was released by the ASACOL MR, ASACOL HD, and MEZAVANT XL formulations at pH 6.0. At pH 6.8, the ASACOL MR and ASACOL HD formulations exhibited complete release of 5-ASA after 4 and 2 h, respectively, and the MEZAVANT XL formulation demonstrated complete 5-ASA release over 6-7 h. 5-Aminosalicylic acid release profiles were variable among various commercially available formulations. Shire Development LLC.
Li, Mingjun; Ma, Fengwang; Liang, Dong; Li, Juan; Wang, Yanlei
2010-12-09
Ascorbic acid (AsA) is a unique antioxidant as well as an enzyme cofactor. Although it has multiple roles in plants, it is unclear how its accumulation is controlled at the expression level, especially in sink tissues. Kiwifruit (Actinidia) is well-known for its high ascorbate content. Our objective was to determine whether AsA accumulates in the fruits primarily through biosynthesis or because it is imported from the foliage. We systematically investigated AsA levels, biosynthetic capacity, and mRNA expression of genes involved in AsA biosynthesis in kiwi (A. deliciosa cv. Qinmei). Recycling and AsA localization were also monitored during fruit development and among different tissue types. Over time, the amount of AsA, with its capacity for higher biosynthesis and lower recycling, peaked at 30 days after anthesis (DAA), and then decreased markedly up to 60 DAA before declining more slowly. Expression of key genes showed similar patterns of change, except for L-galactono-1,4-lactone dehydrogenase and L-galactose-1-phosphate phosphatase (GPP). However, GPP had good correlation with the rate of AsA accumulation. The expression of these genes could be detected in phloem of stem as well as petiole of leaf and fruit. Additionally, fruit petioles had greater ascorbate amounts, although that was the site of lowest expression by most genes. Fruit microtubule tissues also had higher AsA. However, exogenous applications of AsA to those petioles did not lead to its transport into fruits, and distribution of ascorbate was cell-specific in the fruits, with more accumulation occurring in larger cells. These results suggest that AsA biosynthesis in kiwi during early fruit development is the main reason for its accumulation in the fruits. We also postulate here that GPP is a good candidate for regulating AsA biosynthesis whereas GDP-L-galactose-1-phosphate phosphorylase is not.
Iwao, Yasunori; Tomiguchi, Izumi; Domura, Ayaka; Mantaira, Yusuke; Minami, Akira; Suzuki, Takashi; Ikawa, Takashi; Kimura, Shin-Ichiro; Itai, Shigeru
2018-04-01
To develop a new strategy for inflamed site-specific drug delivery in the colon for the treatment of ulcerative colitis (UC), we leveraged on the interaction between myeloperoxidase (MPO) and human serum albumin (HSA) and prepared nanoparticles (HSA NPs) conjugated with 5-aminosalicylic acid (5-ASA). The 5-ASA-HSA NPs (nine molecules of 5-ASA per HSA molecule) were uniform particles with an average particle size of 190 nm, a zeta potential of --11.8 mV, and a polydispersity index of 0.35. This was considered a suitable particle characteristic to pass through the mucus layer and accumulate into the mucosa. The specific interaction between the 5-ASA-HSA NPs and MPO was observed using quartz crystal microbalance analysis in vitro. In addition, the 5-ASA-HSA NPs group containing one thousandth of the dose of the 5-ASA (75 μg/kg) showed significantly lower disease activity index values and colon weight/length ratios in UC model mice as similar to large amount of neat 5-ASA group (75 mg/kg), indicating that the therapeutic effect of the 5-ASA-HSA NP formulation was confirmed in vivo. Microscopic images of tissue sections of colon extracted from UC model mice demonstrated that HSA NPs and MPO were both localized in the colon, and this specific interaction between HSA NPs and MPO would be involved the in the therapeutic effect in vivo. Furthermore, in the 5-ASA and 5-ASA-HSA NPs groups, some inflammatory damage was observed in the colon, but the degree of damage was mild compared with the control and HSA NPs groups, suggesting mucosal repair and replacement with fibrous granulation tissue had occurred. Therefore, these data demonstrated that an HSA NP formulation has the potential to specifically deliver 5-ASA to an inflamed site where MPO is highly expressed. Copyright © 2018 Elsevier B.V. All rights reserved.
Boado, Ruben J; Lu, Jeff Zhiqiang; Hui, Eric K-W; Sumbria, Rachita K; Pardridge, William M
2013-05-01
Metachromatic leukodystrophy (MLD) is a lysosomal storage disorder of the brain caused by mutations in the gene encoding the lysosomal sulfatase, arylsulfatase A (ASA). It is not possible to treat the brain in MLD with recombinant ASA, because the enzyme does not cross the blood-brain barrier (BBB). In the present investigation, a BBB-penetrating IgG-ASA fusion protein is engineered and expressed, where the ASA monomer is fused to the carboxyl terminus of each heavy chain of an engineered monoclonal antibody (MAb) against the human insulin receptor (HIR). The HIRMAb crosses the BBB via receptor-mediated transport on the endogenous BBB insulin receptor, and acts as a molecular Trojan horse to ferry the ASA into brain from blood. The HIRMAb-ASA is expressed in stably transfected Chinese hamster ovary cells grown in serum free medium, and purified by protein A affinity chromatography. The fusion protein retains high affinity binding to the HIR, EC50 = 0.34 ± 0.11 nM, and retains high ASA enzyme activity, 20 ± 1 units/mg. The HIRMAb-ASA fusion protein is endocytosed and triaged to the lysosomal compartment in MLD fibroblasts. The fusion protein was radio-labeled with the Bolton-Hunter reagent, and the [(125) I]-HIRMAb-ASA rapidly penetrates the brain in the Rhesus monkey following intravenous administration. Film and emulsion autoradiography of primate brain shows global distribution of the fusion protein throughout the monkey brain. These studies describe a new biological entity that is designed to treat the brain of humans with MLD following non-invasive, intravenous infusion of an IgG-ASA fusion protein. Copyright © 2012 Wiley Periodicals, Inc.
Takabayashi, Nobuyoshi; Murata, Kyoko; Tanaka, Shiro; Kawakami, Koji
2015-10-01
Low-dose aspirin (ASA) is effective for secondary prevention of ischemic stroke but can increase the risks of hemorrhagic stroke, upper gastrointestinal bleeding (UGIB), and dyspepsia. Prophylactic administration of proton pump inhibitors (PPIs) reduces the risks of these digestive symptoms. We investigated the cost effectiveness of adding a PPI to ASA therapy for ischemic stroke patients in Japan. A Markov state-transition model was developed to compare the cost effectiveness of ASA monotherapy with ASA plus PPI co-therapy in patients with histories of upper gastrointestinal ulcers and ischemic stroke. The model takes into account ASA adherence rate and adverse effects due to ASA, including hemorrhagic stroke and UGIB. The analysis was performed from the perspective of healthcare payers in 2013. In the base case, total life-years by PPI co-therapy and monotherapy were 16.005 and 15.932, respectively. The difference in duration of no therapy (no ASA or PPI) between the therapies was 558.5 days, which would prevent 30.3 recurrences of ischemic stroke per 1000 person-years. The incremental cost-effectiveness ratio of PPI co-therapy relative to monotherapy was ¥1,191,665 (US$11,458) per life-year gained. In a one-way sensitivity analysis, PPI co-therapy was consistently cost effective at a willingness to pay of ¥5,000,000 (US$48,077) per life-year gained. In a probabilistic sensitivity analysis, the probability that PPI co-therapy was cost effective was 89.74% at the willingness to pay. Co-therapy with ASA plus PPI appears to be cost-effective compared with ASA monotherapy. The addition of PPI also appeared to prolong the duration of ASA therapy, thereby reducing the risk of ischemic stroke.
Shams ara, Ali; Sheibani, Vahid; Esmaeilpour, Khadije; Eslaminejad, Touba; Nematollahi-Mahani, Seyed N
2015-09-01
Ischemic stroke is an acute brain insult that induces dramatic changes in the neurons. Treatment of brain stroke is one of the main therapeutic targets of neuroprotective therapies. The aim of this study was to evaluate the protective potential of implanted human umbilical cord mesenchymal stem (hUCMs) cells with/without aspirin (ASA) against focal cerebral ischemia. We assessed the migration and distribution of PKH26-labeled cells after transplantation. After day 10 of transient occlusion, we evaluated the effect of ASA and hUCMs on the recovery of learning and memory in rats by Morris water maze. Afterward, animals were sacrificed, and the infarct area in the brain was evaluated using 2, 3, 5-triphenyltetrazolium chloride staining and also by hematoxylin and eosin. The recovery of learning and memory in ischemic animals that received ASA and hUCM cells improved significantly compared with the untreated ischemic animals. Coadministration of ASA and hUCM cells did not improve the outcome at a comparable rate with ASA and hUCM cells alone. PKH26-labeled cells were detectable in the ischemic area of the brain tissue sections. 2,3,5-Triphenyltetrazolium chloride staining and histologic examinations showed that treatment with ASA and hUCM cells could significantly alter the ischemic area. The results of the present study suggest that ASA and hUCM cells can withstand degenerative changes induced by artificial stroke in the rat. Also the learning and memory disturbance in the ASA and cell-treated animals is less pronounced than ischemic animals. Coadministration of ASA and hUCM cells did not raise the outcome higher than administration of ASA and hUCM cells alone. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.
Silove, D M; Tay, A K; Tol, W A; Tam, N; Dos Reis, N; da Costa, Z; Soares, C; Rees, S
2016-11-15
Adult separation anxiety (ASA) symptoms are prevalent amongst young women in low and middle-income countries and symptoms may be common in pregnancy. No studies have focused on defining distinctive patterns of ASA symptoms amongst pregnant women in these settings or possible associations with trauma exposure and ongoing stressors. In a consecutive sample of 1672 women attending antenatal clinics in Dili, Timor-Leste (96% response), we assessed traumatic events of conflict, ongoing adversity, intimate partner violence (IPV), ASA, post-traumatic stress disorder (PTSD) and severe psychological distress. Latent Class Analysis was used to identify classes of women based on their distinctive profiles of ASA symptoms, comparisons then being made with key covariates including trauma domains of conflict, intimate partner violence (IPV) and ongoing stressors. LCA yielded three classes, comprising a core ASA (4%), a limited ASA (25%) and a low symptom class (61%). The core ASA class reported exposure to multiple traumatic losses and IPV and showed a pattern of comorbidity with PTSD; the limited ASA class predominantly reported exposure to ongoing stressors and was comorbid with severe psychological distress; the low symptom class reported relatively low levels of exposure to trauma and stressors. The study is cross-sectional, cautioning against inferring causal inferences. The core ASA group may be in need of immediate intervention given the high rate of exposure to IPV amongst this class. A larger number of women experiencing a limited array of non-specific ASA symptoms may need assistance to address the immediate stressors of pregnancy. Copyright © 2016 Elsevier B.V. All rights reserved.
Sandborn, William J.; Rubin, David T.; Harper, Joseph R.
2016-01-01
Background: Rectal budesonide foam is a second-generation corticosteroid efficacious for active mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis. This subgroup analysis examined the impact of baseline oral 5-aminosalicylic acid (5-ASA) on the efficacy and safety of budesonide foam in patients with mild to moderate ulcerative proctitis or ulcerative proctosigmoiditis. Methods: Patients received budesonide foam 2 mg/25 mL twice daily for 2 weeks, then once daily for 4 weeks, or placebo, with or without continued stable dosing of baseline oral 5-ASAs, for remission induction at week 6 (primary endpoint) in 2 identically designed, randomized, double-blind, phase 3 studies. Results: Of the 267 and 279 patients randomized to treatment with budesonide foam or placebo (pooled population), 55.1% and 55.2%, respectively, reported baseline 5-ASA use. A significantly greater percentage of patients achieved remission with budesonide foam versus placebo, either with (42.2% versus 31.8%, respectively; P = 0.03) or without (40.0% versus 14.4%; P < 0.0001) baseline 5-ASA use at week 6. A significantly greater percentage of patients achieved a Modified Mayo Disease Activity Index rectal bleeding subscale score of 0 at week 6, regardless of baseline 5-ASA use (5-ASA, 50.3% versus 35.7%; P = 0.003: no 5-ASA, 45.8% versus 19.2%; P < 0.0001). The frequency of adverse events was comparable between groups, regardless of baseline 5-ASA use. Conclusions: Budesonide foam was efficacious and safe for induction of remission of mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis in patients receiving oral 5-ASA at baseline and those who were not (Clinicaltrials.gov: NCT01008410 and NCT01008423). PMID:27416045
Massot, Capucine; Bancel, Doriane; Lopez Lauri, Félicie; Truffault, Vincent; Baldet, Pierre; Stevens, Rebecca; Gautier, Hélène
2013-01-01
Understanding how the fruit microclimate affects ascorbate (AsA) biosynthesis, oxidation and recycling is a great challenge in improving fruit nutritional quality. For this purpose, tomatoes at breaker stage were harvested and placed in controlled environment conditions at different temperatures (12, 17, 23, 27 and 31°C) and irradiance regimes (darkness or 150 µmol m-2 s-1). Fruit pericarp tissue was used to assay ascorbate, glutathione, enzymes related to oxidative stress and the AsA/glutathione cycle and follow the expression of genes coding for 5 enzymes of the AsA biosynthesis pathway (GME, VTC2, GPP, L-GalDH, GLDH). The AsA pool size in pericarp tissue was significantly higher under light at temperatures below 27°C. In addition, light promoted glutathione accumulation at low and high temperatures. At 12°C, increased AsA content was correlated with the enhanced expression of all genes of the biosynthesis pathway studied, combined with higher DHAR and MDHAR activities and increased enzymatic activities related to oxidative stress (CAT and APX). In contrast, at 31°C, MDHAR and GR activities were significantly reduced under light indicating that enzymes of the AsA/glutathione cycle may limit AsA recycling and pool size in fruit pericarp, despite enhanced expression of genes coding for AsA biosynthesis enzymes. In conclusion, this study confirms the important role of fruit microclimate in the regulation of fruit pericarp AsA content, as under oxidative conditions (12°C, light) total fruit pericarp AsA content increased up to 71%. Moreover, it reveals that light and temperature interact to regulate both AsA biosynthesis gene expression in tomato fruits and AsA oxidation and recycling. PMID:24367665
Bosworth, Brian P; Sandborn, William J; Rubin, David T; Harper, Joseph R
2016-08-01
Rectal budesonide foam is a second-generation corticosteroid efficacious for active mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis. This subgroup analysis examined the impact of baseline oral 5-aminosalicylic acid (5-ASA) on the efficacy and safety of budesonide foam in patients with mild to moderate ulcerative proctitis or ulcerative proctosigmoiditis. Patients received budesonide foam 2 mg/25 mL twice daily for 2 weeks, then once daily for 4 weeks, or placebo, with or without continued stable dosing of baseline oral 5-ASAs, for remission induction at week 6 (primary endpoint) in 2 identically designed, randomized, double-blind, phase 3 studies. Of the 267 and 279 patients randomized to treatment with budesonide foam or placebo (pooled population), 55.1% and 55.2%, respectively, reported baseline 5-ASA use. A significantly greater percentage of patients achieved remission with budesonide foam versus placebo, either with (42.2% versus 31.8%, respectively; P = 0.03) or without (40.0% versus 14.4%; P < 0.0001) baseline 5-ASA use at week 6. A significantly greater percentage of patients achieved a Modified Mayo Disease Activity Index rectal bleeding subscale score of 0 at week 6, regardless of baseline 5-ASA use (5-ASA, 50.3% versus 35.7%; P = 0.003: no 5-ASA, 45.8% versus 19.2%; P < 0.0001). The frequency of adverse events was comparable between groups, regardless of baseline 5-ASA use. Budesonide foam was efficacious and safe for induction of remission of mild to moderate ulcerative proctitis and ulcerative proctosigmoiditis in patients receiving oral 5-ASA at baseline and those who were not (Clinicaltrials.gov: NCT01008410 and NCT01008423).
Massot, Capucine; Bancel, Doriane; Lopez Lauri, Félicie; Truffault, Vincent; Baldet, Pierre; Stevens, Rebecca; Gautier, Hélène
2013-01-01
Understanding how the fruit microclimate affects ascorbate (AsA) biosynthesis, oxidation and recycling is a great challenge in improving fruit nutritional quality. For this purpose, tomatoes at breaker stage were harvested and placed in controlled environment conditions at different temperatures (12, 17, 23, 27 and 31 °C) and irradiance regimes (darkness or 150 µmol m(-2) s(-1)). Fruit pericarp tissue was used to assay ascorbate, glutathione, enzymes related to oxidative stress and the AsA/glutathione cycle and follow the expression of genes coding for 5 enzymes of the AsA biosynthesis pathway (GME, VTC2, GPP, L-GalDH, GLDH). The AsA pool size in pericarp tissue was significantly higher under light at temperatures below 27 °C. In addition, light promoted glutathione accumulation at low and high temperatures. At 12 °C, increased AsA content was correlated with the enhanced expression of all genes of the biosynthesis pathway studied, combined with higher DHAR and MDHAR activities and increased enzymatic activities related to oxidative stress (CAT and APX). In contrast, at 31 °C, MDHAR and GR activities were significantly reduced under light indicating that enzymes of the AsA/glutathione cycle may limit AsA recycling and pool size in fruit pericarp, despite enhanced expression of genes coding for AsA biosynthesis enzymes. In conclusion, this study confirms the important role of fruit microclimate in the regulation of fruit pericarp AsA content, as under oxidative conditions (12 °C, light) total fruit pericarp AsA content increased up to 71%. Moreover, it reveals that light and temperature interact to regulate both AsA biosynthesis gene expression in tomato fruits and AsA oxidation and recycling.
Vorapaxar and optimal aspirin dose: The FDA outlook.
Serebruany, Victor L; Fortmann, Seth D; Kim, Moo Hyun
2016-01-15
Vorapaxar, a novel thrombin PAR-1 inhibitor, approved for post-myocardial infarction, and peripheral artery disease indications has been tested in 2 major clinical trials. In the successful TRA2P, antecedent aspirin (ASA) has been used in 94% of patients, and in failed TRACER in over 96% of patients. However, both trial publications were silent on the impact of ASA dose on clinical outcomes after voraparax. We determined which ASA dose range should be used in combination with voraparax based on the TRA2P and TRACER secondary FDA review. The data suggest that for both voraparax trials, younger patients, males, and diabetics received higher ASA doses. The interactions between voraparax efficacy and ASA dose ≥ 300 mg was marginally significant by Cox regressions for TRA2P (CI=1.00-1.61; p=0.048) and strongly trended in TRACER (CI=0.98-1.47; p=0.073). Bleeding rates were overall slightly higher with voraparax than with placebo, and were the highest in patients receiving ASA dosages ≥ 300 mg. However, there were no interactions between ASA dose and GUSTO moderate/severe bleeding. In conclusion, the efficacy of voraparax in TRA2P and TRACER, was slightly worse while bleeding was substantially worse with the higher over 300 mg/day of ASA dosages. Voraparax label should recommend ASA daily use in 75 to 100mg range for concomitant use. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
The ASAS-SN bright supernova catalogue – I. 2013–2014
Holoien, T. W. -S.; Stanek, K. Z.; Kochanek, C. S.; ...
2016-09-12
We present basic statistics for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during its first year-and-a-half of operations, spanning 2013 and 2014. We also present the same information for all other bright (m V ≤ 17), spectroscopically confirmed supernovae discovered from 2014 May 1 through the end of 2014, providing a comparison to the ASAS-SN sample starting from the point where ASAS-SN became operational in both hemispheres. In addition, we present collected redshifts and near-UV through IR magnitudes, where available, for all host galaxies of the bright supernovae in both samples. This work represents a comprehensivemore » catalogue of bright supernovae and their hosts from multiple professional and amateur sources, allowing for population studies that were not previously possible because the all-sky emphasis of ASAS-SN redresses many previously existing biases. In particular, ASAS-SN systematically finds bright supernovae closer to the centres of host galaxies than either other professional surveys or amateurs, a remarkable result given ASAS-SN's poorer angular resolution. In conclusion, this is the first of a series of yearly papers on bright supernovae and their hosts that will be released by the ASAS-SN team.« less
Regulation of ascorbic acid metabolism by blue LED light irradiation in citrus juice sacs.
Zhang, Lancui; Ma, Gang; Yamawaki, Kazuki; Ikoma, Yoshinori; Matsumoto, Hikaru; Yoshioka, Terutaka; Ohta, Satoshi; Kato, Masaya
2015-04-01
In the present study, the effects of red and blue LED lights on the accumulation of ascorbic acid (AsA) were investigated in the juice sacs of three citrus varieties, Satsuma mandarin, Valencia orange, and Lisbon lemon. The results showed that the blue LED light treatment effectively increased the AsA content in the juice sacs of the three citrus varieties, whereas the red LED light treatment did not. By increasing the blue LED light intensity, the juice sacs of the three citrus varieties accumulated more AsA. Moreover, continuous irradiation with blue LED light was more effective than pulsed irradiation for increasing the AsA content in the juice sacs of the three citrus varieties. Gene expression results showed that the modulation of AsA accumulation by blue LED light was highly regulated at the transcription level. The up-regulation of AsA biosynthetic genes (CitVTC1, CitVTC2, CitVTC4, and CitGLDH), AsA regeneration genes (CitMDAR1, CitMDAR2, and CitDHAR) and two GSH-producing genes (CitGR and CitchGR) contributed to these increases in the AsA content in the three citrus varieties. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Allgayer, H; Sonnenbichler, J; Kruis, W; Paumgartner, G
1985-01-01
Sulphasalazine (SASP), used in the treatment of inflammatory bowel disease, is split into sulphapyridine (SP) and 5-aminosalicylic acid (5-ASA) in the colon. Lower plasma levels of SASP and 5-ASA as compared to those of SP may be due to different absorption rates from the colon because of different pK values and pH dependent lipid-water partition coefficients. In this study we determined the pK values of 5-ASA and its major metabolite, N-acetyl amino-salicylic acid (AcASA), by 13C-NMR spectroscopy and compared the pH dependent apparent benzene-water partition coefficients (Papp) of SASP, SP and 5-ASA with respect to their different plasma levels. The COOH group of 5-ASA had a pK value of 3.0, the -NH3+ group had 6.0, the -OH group 13.9; the -COOH group of AcASA had 2.7 and the -OH group 12.9; The Papp of SASP (0.042 +/- 0.004) and 5-ASA (0.059 +/- 0.01) were significantly lower than that of SP (0.092 +/- 0.03) (at pH 5.5).
Structure of ternary additive hard-sphere fluid mixtures.
Malijevský, Alexander; Malijevský, Anatol; Yuste, Santos B; Santos, Andrés; López de Haro, Mariano
2002-12-01
Monte Carlo simulations on the structural properties of ternary fluid mixtures of additive hard spheres are reported. The results are compared with those obtained from a recent analytical approximation [S. B. Yuste, A. Santos, and M. López de Haro, J. Chem. Phys. 108, 3683 (1998)] to the radial distribution functions of hard-sphere mixtures and with the results derived from the solution of the Ornstein-Zernike integral equation with both the Martynov-Sarkisov and the Percus-Yevick closures. Very good agreement between the results of the first two approaches and simulation is observed, with a noticeable improvement over the Percus-Yevick predictions especially near contact.
Rectal 5-aminosalicylic acid for maintenance of remission in ulcerative colitis.
Marshall, John K; Thabane, Marroon; Steinhart, A Hillary; Newman, Jamie R; Anand, Anju; Irvine, E Jan
2012-11-14
5-Aminosalicylic acid (5-ASA) is a first-line therapy for inducing and maintaining remission of mild and moderately active ulcerative colitis (UC). When the proximal margin of inflammation is distal to the splenic flexure, 5-ASA therapy can be delivered as a rectal suppository, foam or liquid enema. The primary objective was to assess the efficacy and safety of rectal 5-ASA for maintaining remission of distal UC. We searched MEDLINE (1966 to August 2012), the Cochrane Library (August 2012), abstracts from major gastroenterology meetings (1997-2011) and bibliographies of relevant publications to identify relevant studies. Eligible studies were randomized controlled trials comparing rectal 5-ASA to placebo or another active treatment for a minimum duration of six months. Symptom scores needed to be assessed in at least one study outcome. Patients had to be at least 12 years of age with disease extent less than 60 cm from the anal verge or distal to the splenic flexure, as determined by barium enema, colonoscopy or sigmoidoscopy. Patients were expected to be in remission prior to the treatment trial. Study eligibility was independently assessed by three authors. Data were extracted using standardized forms by two independent reviewers, with inter-rater agreement assessed using Cohen's Kappa and disagreements resolved by consensus. In cases where clarification of study results or methodology was needed, corresponding authors were contacted. The methodological quality of each trial was assessed by the Cochrane risk of bias tool and by a 30-point scale developed and used previously by the authors. Pooled risk ratios (RR) and corresponding 95% confidence intervals (CI) for continued clinical, endoscopic and histologic remission were estimated for comparisons between rectal 5-ASA and placebo or oral 5-ASA, and for comparisons among 5-ASA doses. Heterogeneity was assessed using the Chi(2) test and visual inspection of forest plots. If no significant heterogeneity was identified (P > 0.10 for Chi(2)) a fixed-effect model (Mantel-Haenstzel) was used. If heterogeneity was significant, a random-effects model was used. Nine studies (484 patients) met the pre-specified inclusion criteria (Kappa 1.00). Six studies were rated as low risk of bias. Three studies were rated as high risk of bias due to blinding (two open label and one single-blind). The total daily dose of rectal 5-ASA ranged from 0.5 g to 4 g, and dose frequency ranged from once to three times daily. 5-ASA was delivered as liquid enema in five studies or as a suppository in four studies. Follow-up ranged from 6 to 24 months. Rectal 5-ASA was significantly superior to placebo for maintenance of symptomatic remission over a period of 12 months.Sixty-two per cent of patients in the rectal 5-ASA group maintained symptomatic remission compared to 30% of patients in the placebo group (4 studies; 301 patients; RR 2.22, 95% CI 1.26 to 3.90; I(2) = 67%; P < 0.01). A GRADE analysis indicated that the overall quality of the evidence for the primary outcome was low due to imprecision (i.e. sparse data 144 events) and inconsistency (i.e. unexplained heterogeneity). Rectal 5-ASA was significantly superior to placebo for maintenance of endoscopic remission over a 12 month period. Seventy-five per cent of patients in the rectal 5-ASA group maintained endoscopic remission compared to 15% of patients in the placebo group (1 study; 25 patients; RR 4.88, 95% CI 1.31 to 18.18; P < 0.05). There was no statistically significant difference in the proportion of patients who experienced at least one adverse event. Sixteen per cent of patients in the rectal 5-ASA group experienced at least one adverse compared to 12% of placebo patients (2 studies; 160 patients; RR 1.35, 95% CI 0.63 to 2.89; I(2) = 0%; P = 0.44). The most commonly reported adverse events were anal irritation and abdominal pain. No statistically significant differences between rectal and oral 5-ASA were identified for either symptomatic or endoscopic remission over a period of six months. Eighty per cent of patients in the rectal 5-ASA group maintained symptomatic remission compared to 65% of patients in the oral 5-ASA group (2 studies; 69 patients; RR 1.24, 95% CI 0.92 to 1.66; I(2) = 0%; P = 0.15). A GRADE analysis indicated that the overall quality of the evidence for the primary outcome was low due to imprecision (i.e. sparse data 50 events) and high risk of bias (i.e. both studies in the pooled analysis were open label). Eighty per cent of patients in the rectal 5-ASA group maintained endoscopic remission compared to 70% of patients in the oral 5-ASA group (2 studies; 91 patients; RR 1.14, 95% CI 0.90 to 1.45; I(2) = 0%; P = 0.26). In two small trials, one comparing 2 g/day 5-ASA enemas to 4 g/day 5-ASA enemas and the other comparing 0.5 g/day 5-ASA suppositories to 1 g/day 5-ASA suppositories no dose response relationship was observed. The limited data available suggest that rectal 5-ASA is effective and safe for maintenance of remission of mild to moderately active distal UC. Well designed randomized trials are needed to establish the optimal dosing regimen for rectal 5-ASA, to compare rectal 5-ASA with rectal corticosteroids and to identify subgroups of patients who are more or less responsive to specific rectal 5-ASA regimens. The combination of oral and rectal 5-ASA appears to be more effective than either oral or rectal monotherapy for induction of remission. The efficacy of combination therapy for maintenance of remission has not been assessed and could be evaluated in future trials.
NASA Astrophysics Data System (ADS)
Stewart, J. B.
2018-02-01
This paper presents experimental data on incident overpressures and the corresponding impulses obtained in the test section of an explosively driven 10° (full angle) conical shock tube. Due to the shock tube's steel walls approximating the boundary conditions seen by a spherical sector cut out of a detonating sphere of energetic material, a 5.3-g pentolite shock tube driver charge produces peak overpressures corresponding to a free-field detonation from an 816-g sphere of pentolite. The four test section geometries investigated in this paper (open air, cylindrical, 10° inscribed square frustum, and 10° circumscribed square frustum) provide a variety of different time histories for the incident overpressures and impulses, with a circumscribed square frustum yielding the best approximation of the estimated blast environment that would have been produced by a free-field detonation.
Kim, Kook Hyun; Kim, Tae Nyeun; Jang, Byung Ik
2007-12-01
Oral 5-aminosalicylic acid (5-ASA) has been known as a first-choice drug for ulcerative colitis. However, hypersensitivity reactions, including pancreatitis, hepatitis, and skin rash, have been reported with 5-ASA. Topical formulations of 5-ASA like suppositories have been rarely reported to induce adverse reactions because of their limited absorption rate. We recently experienced a case of acute pancreatitis caused by 5-ASA suppositories in a patient with ulcerative colitis. A 26-year-old male was admitted with abdominal pain and diagnosed as ulcerative colitis. Acute pancreatitis occurred soon after 24 hours of treatment with oral mesalazine. Drug-induced pancreatitis was suspected and administration of mesalazine was discontinued. Then 5-ASA suppositories were started instead of oral mesalazine. Twenty-four hours after taking 5-ASA suppositories, he experienced severe abdominal pain, fever, and elevation of amylase levels. The suppositories were immediately stopped and symptoms resolved over next 48 hours. Herein, we suggest that, in patients treated with 5-ASA suppositories who complain of severe abdominal pain, drug-induced pancreatitis should be suspected.
Canakçi, S
2003-01-01
The effects of 100, 250, and 500 ppm acetylsalicylic acid solutions treatments on weight alteration, pigment and protein amounts in discs from the primary leaves of one month old bean (Phaseolus vulgaris L.) seedlings produced tinder greenhouse conditions are presented. The experiments show that: 100 ppm ASA had no significant influence (P > 0.05) but 250 and 500 ppm ASA caused an increase on weight loss (P < 0.01); ASA at higher concentrations (250 and 500 ppm), generally, caused a decrease on pigment amounts (P < 0.05-P < 0.01) but 100 ppm ASA had no considerably significant influence on them (P > 0.05), none of the ASA treatments caused a statistically significant influence on carotenoid amount (P > 0.05); 100 and 250 ppm ASA treatments did not cause a significant influence on protein amount (P > 0.05). however 500 ppm ASA treatment caused an increase on protein injury (P < 0.05). Consequently, it is supposed that wet weight loss, pigment and protein injury have somewhat increased on leaf discs. depending on the toxic effect of high acetylsalicylic acid concentrations.
Isolation of saprophytic Leptospira spp. from a selected environmental water source of Argentina.
Scialfa, Exequiel; Grune, Sylvia; Brihuega, Bibiana; Aguirre, Pablo; Rivero, Marina
2017-11-29
Ten Leptospira spp. strains were isolated from water samples from Nievas stream, Olavarría, Buenos Aires province (Argentina). The isolates showed the typical motility and morphology of the genus Leptospira under dark field microscopy, developing in liquid EMJH medium after eight days of incubation at 13°C and 30°C. All isolates were negative by the Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). Molecular identification by 16S rRNA gene sequencing identified all isolates as nonpathogenic leptospires. Four isolates showed a genetic profile identical to that of the reference strain Leptospira biflexa serovar Patoc, and six isolates revealed sequence similarities within the 97-98% range, closely related to Leptospira yanagawae and Leptospira meyeri, respectively. Strains ScialfaASA42, ScialfaASA45, ScialfaASA44, ScialfaASA47, ScialfaASA49, ScialfaASA50 and ScialfaASA51 possibly represent a novel species of the genus Leptospira. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.
Overview of the ASA24® Researcher Website
The ASA24 Researcher Website allows researchers, clinicians, and teachers to register to use the ASA24 system for research, clinical practice, or teaching; to manage logistics of data collection; and to obtain analytic output files.
Ueber den Nachweis von Exoplaneten in der ASAS-3 Datenbank
NASA Astrophysics Data System (ADS)
Huemmerich, Stefan; Bernhard, Klaus
2015-02-01
Under favourable circumstances, transits of known exoplanets with large amplitudes like WASP-18 b can be observed in the ASAS-3 database. An attempt to search for exoplanets using ASAS-3 data is discussed.
ERIC Educational Resources Information Center
Maldonado, Carmen
In an audit of the records and procedures for ASA Institute of Computer and Business Technology, Inc. (ASA), the New York Office of the State Comptroller determined that ASA was overpaid $696,352 because school officials incorrectly certified certain students as eligible for Tuition Assistance Program (TAP) awards. This error was discovered using…
The ASAS-SN Catalog of Variable Stars I: The Serendipitous Survey
NASA Astrophysics Data System (ADS)
Jayasinghe, T.; Kochanek, C. S.; Stanek, K. Z.; Shappee, B. J.; Holoien, T. W.-S.; Thompson, Todd A.; Prieto, J. L.; Dong, Subo; Pawlak, M.; Shields, J. V.; Pojmanski, G.; Otero, S.; Britt, C. A.; Will, D.
2018-04-01
The All-Sky Automated Survey for Supernovae (ASAS-SN) is the first optical survey to routinely monitor the whole sky with a cadence of ˜2 - 3 days down to V≲ 17 mag. ASAS-SN has monitored the whole sky since 2014, collecting ˜100 - 500 epochs of observations per field. The V-band light curves for candidate variables identified during the search for supernovae are classified using a random forest classifier and visually verified. We present a catalog of 66,533 bright, new variable stars discovered during our search for supernovae, including 27,753 periodic variables and 38,780 irregular variables. V-band light curves for the ASAS-SN variables are available through the ASAS-SN variable stars database (https://asas-sn.osu.edu/variables). The database will begin to include the light curves of known variable stars in the near future along with the results for a systematic, all-sky variability survey.
NASA Astrophysics Data System (ADS)
Goerens, Christian; Fokwa, Boniface P. T.
2012-08-01
Polycrystalline samples and single crystals of the new complex boride Ti1+xRh2-x+yIr3-yB3 (x=0.68; y=1.06) were synthesized by arc-melting the elements in a water-cooled copper crucible under an argon atmosphere and characterized by X-Ray diffraction as well as EDX measurements. The crystal structure was refined on the basis of single crystal data. The new phase, which represents a new structure type containing trans zigzag B4 fragments as well as isolated boron atoms crystallizes in the orthorhombic space group Pbam (Nr. 55) with the lattice parameters a=8.620(1) Å, b=14.995(2) Å and c=3.234(1) Å. First-principles density functional theory calculations using the Vienna ab-initio simulation package (VASP) were performed on an appropriate structural model (using a supercell approach) and the experimental crystallographic data could be reproduced accurately. Based on this model, the density of states and crystal orbital Hamilton population (for bonding analysis) were calculated, using the linear muffin-tin orbital atomic sphere approximation (LMTO-ASA) method. According to these calculations, this metal-rich compound should be metallic, as expected. Furthermore, very strong boron-boron interactions are observed in the trans zigzag B4 fragment, which induce a clear differentiation of two types of metal-boron contacts with different strength. The observed three-dimensional metal-metal interaction is in good agreement with the predicted metallic behavior.
A note about Gaussian statistics on a sphere
NASA Astrophysics Data System (ADS)
Chave, Alan D.
2015-11-01
The statistics of directional data on a sphere can be modelled either using the Fisher distribution that is conditioned on the magnitude being unity, in which case the sample space is confined to the unit sphere, or using the latitude-longitude marginal distribution derived from a trivariate Gaussian model that places no constraint on the magnitude. These two distributions are derived from first principles and compared. The Fisher distribution more closely approximates the uniform distribution on a sphere for a given small value of the concentration parameter, while the latitude-longitude marginal distribution is always slightly larger than the Fisher distribution at small off-axis angles for large values of the concentration parameter. Asymptotic analysis shows that the two distributions only become equivalent in the limit of large concentration parameter and very small off-axis angle.
Discovery of a Frank-Kasper [sigma] Phase in Sphere-Forming Block Copolymer Melts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Sangwoo; Bluemle, Michael J.; Bates, Frank S.
Sphere-forming block copolymers are known to self-assemble into body-centered cubic crystals near the order-disorder transition temperature. Small-angle x-ray scattering and transmission electron microscopy experiments on diblock and tetrablock copolymer melts have revealed an equilibrium phase characterized by a large tetragonal unit cell containing 30 microphase-separated spheres. This structure, referred to as the sigma ({sigma}) phase by Frank and Kasper more than 50 years ago, nucleates and grows from the body-centered cubic phase similar to its occurrence in metal alloys and is a crystal approximant to dodecagonal quasicrystals. Formation of the {sigma} phase in undiluted linear block copolymers (and certain branchedmore » dendrimers) appears to be mediated by macromolecular packing frustration, an entropic contribution to the interparticle interactions that control the sphere-packing geometry.« less
Kamenova, Maria; Nevzati, Edin; Lutz, Katharina; Dolp, Armando; Fandino, Javier; Mariani, Luigi; Soleman, Jehuda
2017-04-01
Chronic subdural hematoma (cSDH) is one of the most common neurosurgical diseases typically affecting older people. Many of these patients have coronary artery disease and receive antiplatelet therapy, usually acetylsalicylic acid (ASA). Despite growing clinical relevance, there is still a lack of data focusing on the perioperative management of such patients. The aim of this study is to compare the perioperative and postoperative bleeding and cardiovascular complication rates of patients undergoing burr-hole drainage for cSDH with and without discontinuation of low-dose ASA. Of 963 consecutive patients undergoing burr-hole drainage for cSDH, 198 (20.5%) patients were receiving low-dose ASA treatment. In 26 patients (13.1%), ASA was not discontinued (ASA group; ASA discontinuation ≤7 days); in the remaining patients (n = 172; 86.9%), ASA was discontinued at least for 7 days (control group). The primary outcome measure was recurrent cSDH that required revision surgery owing to clinical symptoms, whereas secondary outcome measures were postoperative cardiovascular and thromboembolic events, other complications, operation and hospitalization time, morbidity, and mortality. No statistically significant difference was observed between the 2 groups regarding recurrence of cSDH (P = 1). Cardiovascular event rates, surgical morbidity, and mortality did not significantly differ between patients with and without discontinuation of low-dose ASA. Given the lack of guidelines regarding perioperative management with antiplatelet therapy, our findings elucidate one issue, showing comparable recurrence rates with and without discontinuation of low-dose ASA in patients undergoing burr-hole drainage for cSDH. Copyright © 2017 Elsevier Inc. All rights reserved.
Ho, C W; Tse, Y K; Wu, B; Mulder, C J J; Chan, F K L
2013-04-01
Poor adherence to gastroprotective agents (GPAs) is common among users of nonsteroidal anti-inflammatory drugs (NSAIDs) or low-dose aspirin (ASA). There are little data on the utilization of GPAs among NSAID and ASA users complicated by ulcer bleeding. To study the utilization of GPA among NSAID and ASA ulcers before the onset of ulcer bleeding. We conducted a cross-sectional study to determine the exposure to NSAIDs, ASA, and GPAs within 4 weeks before endoscopically confirmed ulcer bleeding. Sensitivity analysis was performed to study how improving adherence to GPA use would reduce the risk of ulcer bleeding in high-risk users. Between 2000 and 2009, 1093 and 2277 patients had NSAID- and ASA-associated ulcer bleeding respectively. The incidence of NSAID-associated ulcer bleeding declined by 40%, whereas that of ASA-associated ulcer bleeding increased by 46%. Thirty-nine per cent of NSAID users and 75% of ASA users belonged to high ulcer risk category. Although GPA prescription rate has increased over time, only 41.6% and 30.6% of high-risk NSAID and ASA users received GPAs before ulcer bleeding respectively. Sensitivity analysis showed that if GPAs could reduce bleeding risk by 50%, improving adherence would prevent up to 35% of ulcer bleeding in high-risk users. A substantial proportion of high-risk NSAID and ASA users had not received prophylaxis with gastroprotective agents before ulcer bleeding. These bleeding episodes may be preventable with better adherence to gastroprotective agent use. © 2013 Blackwell Publishing Ltd.
Römkens, Tessa E H; Kampschreur, Milou T; Drenth, Joost P H; van Oijen, Martijn G H; de Jong, Dirk J
2012-11-01
Recently, mucosal healing (MH) is regarded as an important treatment goal in ulcerative colitis (UC). 5-Aminosalicylates (5-ASA) are the standard treatment in mild-to-moderate UC, but the effect on MH is less known. The aim of this study was to systematically review the medical literature in order to compare different preparations of 5-ASA for the effect on MH. We conducted a structured search of PubMed and the Cochrane Central Register of Controlled Trials to identify randomized controlled clinical trials with 5-ASA in UC providing data about MH. We calculated the sample size-weighted pooled proportion of patients with MH, and performed meta-analysis of head-to-head comparisons. Out of 645 hits, we included 90 treatment arms, involving 3977 patients using oral 5-ASA (granulate and tablets) and 2513 patients using rectal 5-ASA (suppositories, enema, and foam). Overall, 43,7% of 5-ASA treated patients achieved MH (oral 36,9%; rectal 50,3%). In oral studies, 49% of patients using granulate (7 treatment-arms) achieved MH compared to 34,9% using tablets (43 treatment-arms). In rectal studies the proportion of MH was 62% for suppositories (eight treatment arms), 51% for foam (nine treatment arms), and 46% for enema (23 treatment arms), respectively. 5-ASA preparations achieved MH in nearly 50% of UC patients. There were no significant differences in MH between the various 5-ASA agents, either in the oral or the rectal treatment groups. Copyright © 2012 Crohn's & Colitis Foundation of America, Inc.
Soleman, Jehuda; Kamenova, Maria; Guzman, Raphael; Mariani, Luigi
2017-11-01
The aim of this international survey was to investigate the current management of patients undergoing surgery for chronic subdural hematoma (cSDH) treated with low-dose acetylsalicylic acid (ASA). We administered a survey via e-mail to neurosurgeons with questions relating to the surgical treatment of cSDH, emphasizing their practices with patients treated with low-dose ASA. We received 157 responses, with a response rate of 22.4%. Almost 80% of the responders discontinue ASA treatment at least 5 days before surgery and 80.7% resume treatment after 5 days or more, and 27.6% discontinue treatment for at least 30 days. The main factor influencing ASA resumption time is the indication for ASA (54.5%), and postoperative imaging is concluded in 71.7%, Postoperative thrombosis prophylaxis is administered by 60% of the responders, and 50% apply it 24 hours after surgery. Almost 95% of the responders believe that better evidence is needed for the management of patients with cSDH treated with ASA. Guidelines for these patients exist in only 24.3% of the institutes. Most neurosurgeons discontinue ASA treatment for at least 7 days in the perioperative period of surgical evacuation of cSDH, even though recent studies show that early ASA resumption might be safe. Thrombosis prophylaxis is administered by only 60%, even though patients with cSDH are at high risk of developing thromboembolic complications. Better evidence and guidelines are warranted because the incidence of patients with cSDH under the treatment of ASA is increasing. Copyright © 2017 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Attard, Phil
The second moment of the Lennard-Jones local field distribution in a hard-sphere fluid is evaluated using the PY3 three-particle distribution function. An approximation due to Lado that avoids the explicit calculation of the latter is shown to be accurate. Partial results are also given for certain cavity-hard-sphere radial distribution functions that occur in a closest particle expansion for the local field.
Zhang, Chanjuan; Ouyang, Bo; Yang, Changxian; Zhang, Xiaohui; Liu, Hui; Zhang, Yuyang; Zhang, Junhong; Li, Hanxia; Ye, Zhibiao
2013-01-01
As a vital antioxidant, L-ascorbic acid (AsA) affects diverse biological processes in higher plants. Lack of AsA in cell impairs plant development. In the present study, we manipulated a gene of GDP-mannose pyrophosphorylase which catalyzes the conversion of D-mannose-1-P to GDP-D-mannose in AsA biosynthetic pathway and found out the phenotype alteration of tomato. In the tomato genome, there are four members of GMP gene family and they constitutively expressed in various tissues in distinct expression patterns. As expected, over-expression of SlGMP3 increased total AsA contents and enhanced the tolerance to oxidative stress in tomato. On the contrary, knock-down of SlGMP3 significantly decreased AsA contents below the threshold level and altered the phenotype of tomato plants with lesions and further senescence. Further analysis indicated the causes for this symptom could result from failing to instantly deplete the reactive oxygen species (ROS) as decline of free radical scavenging activity. More ROS accumulated in the leaves and then triggered expressions of defence-related genes and mimic symptom occurred on the leaves similar to hypersensitive responses against pathogens. Consequently, the photosynthesis of leaves was dramatically fallen. These results suggested the vital roles of AsA as an antioxidant in leaf function and defence response of tomato.
Genetic control of ascorbic acid biosynthesis and recycling in horticultural crops
NASA Astrophysics Data System (ADS)
Mellidou, Ifigeneia; Kanellis, Angelos K.
2017-07-01
Ascorbic acid (AsA) is an essential compound present in almost all living organisms that has important functions in several aspects of plant growth and development, hormone signalling, as well as stress defense networks. In recent years, the genetic regulation of AsA metabolic pathways has received much attention due to its beneficial role in human diet. Despite the great variability within species, genotypes, tissues and developmental stages, AsA accumulation is considered to be controlled by the fine orchestration of net biosynthesis, recycling, degradation/oxidation, and/or intercellular and intracellular transport. To date, several structural genes from the AsA metabolic pathways and transcription factors are considered to significantly affect AsA in plant tissues, either at the level of activity, transcription or translation via feedback inhibition. Yet, all the emerging studies support the notion that the steps proceeding through GDP-L-galactose phosphorylase and to a lesser extent through GDP-D-mannose-3,5-epimerase are control points in governing AsA pool size in several species. In this mini review, we discuss the current consensus of the genetic regulation of AsA biosynthesis and recycling, with a focus on horticultural crops. The aspects of AsA degradation and transport are not discussed herein. Novel insights of how this multifaceted trait is regulated are critical to prioritize candidate genes for follow-up studies towards improving the nutritional value of fruits and vegetables.
5-ASA in ulcerative colitis: improving treatment compliance.
Prantera, Cosimo; Rizzi, Marina
2009-09-21
5-Aminosalicylic acid (5-ASA) compounds are a highly effective treatment for ulcerative colitis (UC). While UC patient compliance in clinical studies is over 90%, only 40% of patients in every day life take their prescribed therapy. Adherence to medication has been emphasized recently by a Cochrane meta-analysis that has suggested that future trials of 5-ASA in UC should look at patient compliance rather than drug efficacy. Better compliance can be obtained by reducing the number of tablets and times of administration. Given that the 5-ASA formulations have different delivery systems that split the active moiety in various regions of the intestine, it is particularly important that an adequate dose of the drug arrives at the inflamed part of the colon. 5-ASA Multi matrix (MMx) is a novel, high strength (1.2 g), oral formulation designed for once-daily dosing. It releases the active moiety throughout the colon. Different studies with this compound have shown that it is as effective as 5-ASA enema in the treatment of mild-to-moderate, left-sided UC, and is comparable to a pH-dependent, delayed release 5-ASA (Asacol), even if given once daily. Recently, the effectiveness in the acute phase of UC has been confirmed also in maintenance. In conclusion, at present, 5-ASA MMx seems theoretically the best agent for maintaining patient compliance, and consequently, treatment effectiveness.
Guo, Yue; Su, Zheng-Yuan; Zhang, Chengyue; Gaspar, John M; Wang, Rui; Hart, Ronald P; Verzi, Michael P; Kong, Ah-Ng Tony
2017-07-01
Colorectal cancer (CRC) remains the leading cause of cancer-related death in the world. Aspirin (ASA) and curcumin (CUR) are widely investigated chemopreventive candidates for CRC. However, the precise mechanisms of their action and their combinatorial effects have not been evaluated. The purpose of the present study was to determine the effect of ASA, CUR, and their combination in azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis-accelerated colorectal cancer (CAC). We also aimed to characterize the differential gene expression profiles in AOM/DSS-induced tumors as well as in tumors modulated by ASA and CUR using RNA-seq. Diets supplemented with 0.02% ASA, 2% CUR or 0.01% ASA+1% CUR were given to mice from 1week prior to the AOM injection until the experiment was terminated 22weeks after AOM initiation. Our results showed that CUR had a superior inhibitory effect in colon tumorigenesis compared to that of ASA. The combination of ASA and CUR at a lower dose exhibited similar efficacy to that of a higher dose of CUR at 2%. RNA isolated from colonic tissue from the control group and from tumor samples from the experimental groups was subjected to RNA-seq. Transcriptomic analysis suggested that the low-dose combination of ASA and CUR modulated larger gene sets than the single treatment. These differentially expressed genes were situated in several canonical pathways important in the inflammatory network and liver metastasis in CAC. We identified a small subset of genes as potential molecular targets involved in the preventive action of the combination of ASA and CUR. Taken together, the current results provide the first evidence in support of the chemopreventive effect of a low-dose combination of ASA and CUR in CAC. Moreover, the transcriptional profile obtained in our study may provide a framework for identifying the mechanisms underlying the carcinogenesis process from normal colonic tissue to tumor development as well as the cancer inhibitory effects and potential molecular targets of ASA and CUR. Copyright © 2017 Elsevier Inc. All rights reserved.
Lima-Silva, Viviana; Rosado, Abel; Amorim-Silva, Vitor; Muñoz-Mérida, Antonio; Pons, Clara; Bombarely, Aureliano; Trelles, Oswaldo; Fernández-Muñoz, Rafael; Granell, Antonio; Valpuesta, Victoriano; Botella, Miguel Ángel
2012-05-14
L-ascorbic acid (AsA; vitamin C) is essential for all living plants where it functions as the main hydrosoluble antioxidant. It has diverse roles in the regulation of plant cell growth and expansion, photosynthesis, and hormone-regulated processes. AsA is also an essential component of the human diet, being tomato fruit one of the main sources of this vitamin. To identify genes responsible for AsA content in tomato fruit, transcriptomic studies followed by clustering analysis were applied to two groups of fruits with contrasting AsA content. These fruits were identified after AsA profiling of an F8 Recombinant Inbred Line (RIL) population generated from a cross between the domesticated species Solanum lycopersicum and the wild relative Solanum pimpinellifollium. We found large variability in AsA content within the RIL population with individual RILs with up to 4-fold difference in AsA content. Transcriptomic analysis identified genes whose expression correlated either positively (PVC genes) or negatively (NVC genes) with the AsA content of the fruits. Cluster analysis using SOTA allowed the identification of subsets of co-regulated genes mainly involved in hormones signaling, such as ethylene, ABA, gibberellin and auxin, rather than any of the known AsA biosynthetic genes. Data mining of the corresponding PVC and NVC orthologs in Arabidopis databases identified flagellin and other ROS-producing processes as cues resulting in differential regulation of a high percentage of the genes from both groups of co-regulated genes; more specifically, 26.6% of the orthologous PVC genes, and 15.5% of the orthologous NVC genes were induced and repressed, respectively, under flagellin22 treatment in Arabidopsis thaliana. Results here reported indicate that the content of AsA in red tomato fruit from our selected RILs are not correlated with the expression of genes involved in its biosynthesis. On the contrary, the data presented here supports that AsA content in tomato fruit co-regulates with genes involved in hormone signaling and they are dependent on the oxidative status of the fruit.
NASA Astrophysics Data System (ADS)
Shao, Hongbing
Software testing with scientific software systems often suffers from test oracle problem, i.e., lack of test oracles. Amsterdam discrete dipole approximation code (ADDA) is a scientific software system that can be used to simulate light scattering of scatterers of various types. Testing of ADDA suffers from "test oracle problem". In this thesis work, I established a testing framework to test scientific software systems and evaluated this framework using ADDA as a case study. To test ADDA, I first used CMMIE code as the pseudo oracle to test ADDA in simulating light scattering of a homogeneous sphere scatterer. Comparable results were obtained between ADDA and CMMIE code. This validated ADDA for use with homogeneous sphere scatterers. Then I used experimental result obtained for light scattering of a homogeneous sphere to validate use of ADDA with sphere scatterers. ADDA produced light scattering simulation comparable to the experimentally measured result. This further validated the use of ADDA for simulating light scattering of sphere scatterers. Then I used metamorphic testing to generate test cases covering scatterers of various geometries, orientations, homogeneity or non-homogeneity. ADDA was tested under each of these test cases and all tests passed. The use of statistical analysis together with metamorphic testing is discussed as a future direction. In short, using ADDA as a case study, I established a testing framework, including use of pseudo oracles, experimental results and the metamorphic testing techniques to test scientific software systems that suffer from test oracle problems. Each of these techniques is necessary and contributes to the testing of the software under test.
Citing ASA24® Dietary Assessment Tool in Publications & Presentations
In order to show and maintain support for ASA24, documenting its use in through publications is extremely useful to the National Cancer Institute (NCI). Please cite ASA24 as follows, depending on the version used in your study.
Transient kinetics of the rapid shape change of unstirred human blood platelets stimulated with ADP.
Deranleau, D A; Dubler, D; Rothen, C; Lüscher, E F
1982-01-01
Unstirred (isotropic) suspensions of human blood platelets stimulated with ADP in a stopped-flow laser turbidimeter exhibit a distinct extinction maximum during the course of the classical rapid conversion of initially smooth flat discoid cells to smaller-body spiny spheres. This implies the existence of a transient intermediate having a larger average light scattering cross section (extinction coefficient) than either the disc or the spiny sphere. Monophasic extinction increases reaching the same final value were observed when either discoid or spiny sphere platelets were converted to smooth spheres by treatment with chlorpromazine, and sphering of discoid cells was accompanied by a larger total extinction change than the retraction of pseudopods by already spherical cells. These and other results suggest that the ADP-induced transient state represents platelets that are approximately as "spherical" as the irregular spiny sphere but lack the characteristic long pseudopods and as a consequence are larger bodied. Fitting the ADP progress curves to the series reaction A leads to B leads to C by means of the light scattering equivalent of the Beer-Lambert law yielded scattering cross sections that are consistent with this explanation. The rate constants for the two reaction steps were identical, indicating that ADP activation corresponds to a continuous random (Poisson) process with successive apparent states "disc," "sphere," and "spiny sphere," whose individual probabilities are determined by a single rate-limiting step. PMID:6961409
de Graaf, P; de Boer, NKH; Wong, DR; Karner, S; Jharap, B; Hooymans, PM; Veldkamp, AI; Mulder, CJJ; van Bodegraven, AA; Schwab, M
2010-01-01
Background and purpose: 5-aminosalicylate (5-ASA) raises levels of 6-thioguanine nucleotides (6-TGN), the active metabolites of thiopurines such as azathioprine (AZA). Changes in levels of each individual TGN – 6-thioguanosine mono-, di- and triphosphate (6-TGMP, 6-TGDP, 6-TGTP) – and of 6-methylmercaptopurine ribonucleotides (6-MMPR) after 5-ASA are not known. Experimental approach: Effects of increasing 5-ASA doses on AZA metabolites were investigated prospectively in 22 patients with inflammatory bowel disease in 4-week study periods. Patients started with 2 g 5-ASA daily, and then were increased to 4 g daily and followed by a washout period. Thiopurine doses remained unchanged throughout the entire study. Levels of 6-TGMP, 6-TGDP, 6-TGTP and 6-MMPR as well as of 5-ASA and N-acetyl-5-aminosalicylic acid (N-Ac-5-ASA) were determined each study period. Key results: Median baseline levels in 17 patients of 6-TGDP, 6-TGTP and 6-MMPR were 52, 319 and 1676 pmol per 8 × 108 red blood cells respectively. After co-administration of 2 g 5-ASA daily, median 6-TGDP and 6-TGTP levels increased but median 6-MMPR levels were unchanged. Increasing 5-ASA to 4 g daily did not affect median 6-TGDP and 6-TGTP levels, but median 6-MMPR levels decreased. After discontinuation of 5-ASA, both 6-TGDP and 6-TGTP levels decreased and median 6-MMPR levels increased. The 6-TGTP/(6-TGDP+6-TGTP)-ratio did not change during the study, but 6-MMPR/6-TGN ratios decreased. Conclusions and implications: Individual 6-TGN metabolites increased after addition of 5-ASA, but 6-MMPR-levels and the 6-MMPR/6-TGN ratios decreased. Further studies are needed to decide whether this pharmacokinetic interaction would result in improvement of efficacy and/or increased risk of toxicity of AZA. PMID:20590602
Kamenova, Maria; Lutz, Katharina; Schaedelin, Sabine; Fandino, Javier; Mariani, Luigi; Soleman, Jehuda
2016-11-01
Antiplatelet therapy in patients with chronic subdural hematoma (cSDH) presents significant neurosurgical challenges. Given the lack of guidelines regarding perioperative management with antiplatelet therapy, it is difficult to balance the patient's increased cardiovascular risk and prevalence of cSDH. To better understand the risk and recurrence rates related to resuming low-dose acetylsalicylic acid (ASA) by evaluating our patients' resumption of low-dose ASA at various times after burr-hole drainage of the hematoma. In our retrospective study, 140 consecutive patients taking low-dose ASA undergoing surgical evacuation of cSDH were included. Data included baseline characteristics and rates of recurrence, morbidity, and mortality. A multivariate logistic regression model analyzed the association between ASA resumption time and recurrence rates. No statistically significant association was observed between early postoperative resumption of low-dose ASA and recurrence of cSDH (odds ratio, 1.01; 95% confidence interval, 1.001-1.022; P = .06). Corresponding odds ratios and risk differences for restarting ASA treatment on postoperative days 1, 7, 14, 21, 28, 35, or 42 were estimated at 1.53 and 5.9%, 1.42 and 5.1%, 1.33 and 4.1%, 1.23 and 3.2%, 1.15 and 2.2%, 1.07 and 1.1%, and 1.01 and 0.2%, respectively (P > .05). Cardiovascular event rates, surgical morbidity, and mortality did not significantly differ between patients with or without ASA therapy. Given the few published studies regarding ASA use in cranial neurosurgery, our findings elucidate one issue, showing comparable recurrence rates with early or late resumption of low-dose ASA after burr-hole evacuation of cSDH. ASA, acetylsalicylic acidCAD, coronary artery diseaseCI, confidence intervalcSDH, chronic subdural hematomaGCS, Glasgow Coma ScalemRS, modified Rankin ScaleOR, odds ratioRD, risk difference.
NASA Astrophysics Data System (ADS)
Barrett, Bridget M.
The purpose of this study was to examine the status of antioxidant vitamins in women with premature rupture of the fetal membranes. Specimens of blood and amniotic fluid were obtained from 80 pregnant subjects included both smokers and non-smokers during the third trimester. The concentrations of ascorbic acid (ASA), beta -carotene, retinol and alpha -tocopherol in serum and amniotic fluid were determined. The experimental group consisted of those subjects with PROM while the control subjects were those with normal pregnancy. No statistical differences were found between the PROM and control groups in retinol and vitamin E concentrations in amniotic fluid and serum. Serum ASA concentrations of PROM subjects were not different from controls, but the PROM subjects had significantly lower amniotic fluid ASA concentrations. However, in a study with fewer subjects a lower serum ASA concentration in the PROM subjects was observed. The ratio of amniotic fluid ASA concentration to ASA serum concentration was significantly lower in PROM patients than in controls in both studies. This suggests that low levels of ASA in the amniotic fluid, but not in serum is better associated with PROM. A low amniotic fluid concentration of ASA may reflect an inefficient transfer and/or increased fetal utilization. Alterations in ASA concentration in the amniotic fluid may affect the integrity of the chorioamnion leading to PROM. beta -Carotene was not found in the amniotic fluid. Serum beta-carotene levels were significantly lower in the PROM group compared to the control group. Low concentrations of beta-carotene in maternal serum in smokers not only associated with poor maternal outcome (PROM) but also compromised the fetal outcome (decreased birth weight). Maintenance of adequate serum beta-carotene concentration and amniotic fluid ASA in smokers may result in better maternal and fetal outcome. This study demonstrated that nutrition is an important factor in the prevention of PROM.
Kavitha, Chandagirikoppal V.; Jain, Anil K.; Agarwal, Chapla; Pierce, Angela; Keating, Amy; Huber, Kendra M.; Serkova, Natalie J.; Wempe, Michael F.; Agarwal, Rajesh; Deep, Gagan
2014-01-01
Glioblastoma multiforme (GBM) is an untreatable malignancy. Existing therapeutic options are insufficient, and adversely affect functional and non-cancerous cells in the brain impairing different functions of the body. Therefore, there is an urgent need for additional preventive and therapeutic non-toxic drugs against GBM. Asiatic acid (AsA; 2,3,23-trihydroxy-12-ursen-28-oic acid, C30H48O5) is a natural small molecule widely used to treat various neurological disorders, and the present research investigates AsA’s efficacy against GBM both in vitro and in vivo. Results showed that AsA treatment (10–100 μM) decreased the human GBM cell (LN18, U87MG, and U118MG) viability, with better efficacy than temozolomide at equimolar doses. Orally administered AsA (30 mg/kg/day) strongly decreased tumor volume in mice when administered immediately after ectopic U87MG xenograft implantation (54% decrease, p≤0.05) or in mice with established xenografts (48% decrease, p≤0.05) without any apparent toxicity. Importantly, AsA feeding (30 mg/kg/twice a day) also decreased the orthotopic U87MG xenografts growth in nude mice as measured by magnetic resonance imaging. Using LC/MS-MS methods, AsA was detected in mice plasma and brain tissue, confirming that AsA crosses blood-brain barrier. Mechanistic studies showed that AsA induces apoptotic death by modulating the protein expression of several apoptosis regulators (caspases, Bcl2 family members, and survivin) in GBM cells. Furthermore, AsA induced ER stress (increased GRP78 and Calpain, and decreased Calnexin and IRE1α expression), enhanced free intra-cellular calcium, and damaged cellular organization in GBM cells. These experimental results demonstrate that AsA is effective against GBM, and advocate further pre-clinical and clinical evaluations of AsA against GBM. PMID:25252179
The pharmacological profile and clinical use of mesalazine (5-aminosalicylic acid).
Klotz, U
2012-02-01
For more than 30 years mesalazine (5-aminosalicylic acid; 5-ASA) has been used for the treatment of chronic inflammatory bowel disease (IBD) especially in ulcerative colitis (UC). During this time various rectal and oral formulations have been developed. The modified drug delivery systems were designed to release sufficient 5-ASA at the sites of inflammation. Such a drug targeting strategy is needed for its topical action and especially because local concentrations in the mucosa will determine the clinical outcome. The absorbed part (20-40% of the dose) of 5-ASA is rapidly and presystemically acetylated (t1/2: 1-2.5 h; CL: 300-690 mL/min). Consequently, the systemic exposure of 5-ASA is low and adverse effects are in the range of placebo treatment. The polypotent 5-ASA has a wide spectrum of pharmacological properties and its exact mode of action is not yet clear. Recent meta-analyses of randomized placebo-controlled clinical trials provide convincing data that 5-ASA is the preferred first-line therapy for the acute treatment of mild-to-moderate UC (NNT:6) and for remission management (NNT:4). There is also some clinical benefit for patients with active Crohn's disease (NNT:7) and in the prevention of postsurgical relapse (NNT:10). There is increasing evidence that 5-ASA also has some therapeutic potential for chemoprevention of colorectal cancer, diverticular disease and irritable bowel syndrome. In all clinical studies, the side effects of 5-ASA were very low (5-10%), mild and comparable to placebo. Thus, its use is very safe and 5-ASA will remain an interesting and valuable agent. It is anticipated that more selective drug targeting, including galenic innovations and an optimized dosaging schedule, could result in some improvement of the wide use of 5-ASA. © Georg Thieme Verlag KG Stuttgart · New York.
3D printing of modified-release aminosalicylate (4-ASA and 5-ASA) tablets.
Goyanes, Alvaro; Buanz, Asma B M; Hatton, Grace B; Gaisford, Simon; Basit, Abdul W
2015-01-01
The aim of this study was to explore the potential of fused-deposition 3-dimensional printing (FDM 3DP) to produce modified-release drug loaded tablets. Two aminosalicylate isomers used in the treatment of inflammatory bowel disease (IBD), 5-aminosalicylic acid (5-ASA, mesalazine) and 4-aminosalicylic acid (4-ASA), were selected as model drugs. Commercially produced polyvinyl alcohol (PVA) filaments were loaded with the drugs in an ethanolic drug solution. A final drug-loading of 0.06% w/w and 0.25% w/w was achieved for the 5-ASA and 4-ASA strands, respectively. 10.5mm diameter tablets of both PVA/4-ASA and PVA/5-ASA were subsequently printed using an FDM 3D printer, and varying the weight and densities of the printed tablets was achieved by selecting the infill percentage in the printer software. The tablets were mechanically strong, and the FDM 3D printing was shown to be an effective process for the manufacture of the drug, 5-ASA. Significant thermal degradation of the active 4-ASA (50%) occurred during printing, however, indicating that the method may not be appropriate for drugs when printing at high temperatures exceeding those of the degradation point. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) of the formulated blends confirmed these findings while highlighting the potential of thermal analytical techniques to anticipate drug degradation issues in the 3D printing process. The results of the dissolution tests conducted in modified Hank's bicarbonate buffer showed that release profiles for both drugs were dependent on both the drug itself and on the infill percentage of the tablet. Our work here demonstrates the potential role of FDM 3DP as an efficient and low-cost alternative method of manufacturing individually tailored oral drug dosage, and also for production of modified-release formulations. Copyright © 2014 Elsevier B.V. All rights reserved.
Ascorbic acid metabolism during sweet cherry (Prunus avium) fruit development
Ni, Zhiyou; Lin, Lijin; Tang, Yi; Wang, Zhihui; Wang, Xun; Wang, Jin; Lv, Xiulan; Xia, Hui
2017-01-01
To elucidate metabolism of ascorbic acid (AsA) in sweet cherry fruit (Prunus avium ‘Hongdeng’), we quantified AsA concentration, cloned sequences involved in AsA metabolism and investigated their mRNA expression levels, and determined the activity levels of selected enzymes during fruit development and maturation. We found that AsA concentration was highest at the petal-fall period (0 days after anthesis) and decreased progressively during ripening, but with a slight increase at maturity. AsA did nevertheless continue to accumulate over time because of the increase in fruit fresh weight. Full-length cDNAs of 10 genes involved in the L-galactose pathway of AsA biosynthesis and 10 involved in recycling were obtained. Gene expression patterns of GDP-L-galactose phosphorylase (GGP2), L-galactono-1, 4-lactone dehydrogenase (GalLDH), ascorbate peroxidase (APX3), ascorbate oxidase (AO2), glutathione reductase (GR1), and dehydroascorbate reductase (DHAR1) were in accordance with the AsA concentration pattern during fruit development, indicating that genes involved in ascorbic acid biosynthesis, degradation, and recycling worked in concert to regulate ascorbic acid accumulation in sweet cherry fruit. PMID:28245268
Standards 101: The ASA Standards program
NASA Astrophysics Data System (ADS)
Schomer, Paul
2004-05-01
ASA serves as a standards developer under the auspices of the American National Standards Institute (ANSI). The Standards Program is organized through four technical committees (S1, S2, S3, and S12) and one administrative committee (ASACOS). S1 deals with physical acoustics, S2 deals with shock and vibration, S3 deals with physiological and psychological acoustics and S12 deals with noise. ASACOS is the ASA Committee on Standards. The program has three primary tasks: (1) development of national standards (ANSI Standards), (2) national adoption of international standards (ANSI NAIS Standards), (3) providing the USA input to the development of international standards (ISO and IEC Standards). At every level the main work is accomplished in Working Groups (WG) that are staffed by hundreds of volunteers, mainly ASA members from its various technical committees such as Noise, Physical Acoustics, Architectural Acoustics, Physiological and Psychological Acoustics, etc. Overall, the Standards Program involves more ASA members than does any other single function of the society except meetings. It is the biggest outreach function of ASA affecting the health, welfare, and economic well-being of large sectors of society. It is a main way the ASA diffuses the knowledge of acoustics and its practical application, perhaps the main way.
Atlanta Streets Alive: A Movement Building a Culture of Health in an Urban Environment.
Torres, Andrea; Steward, John; Strasser, Sheryl; Lyn, Rodney; Serna, Rebecca; Stauber, Christine
2016-02-01
Open Streets are community-based programs that promote the use of public space for physical activity (PA), recreation and socialization by closing streets temporarily to motorized vehicles, allowing access to pedestrians. The city of Atlanta hosted its first Open Streets event, Atlanta Streets Alive (ASA), in May 2010. An evaluation of the first 5 ASA events from May 2010 to May 2012 was conducted. The purpose was to learn about the characteristics of ASA participants, the influence of the event on their PA, and perceptions of safety and neighborhood social capital. ASA's evaluation had 2 components: participant counts and a participant survey. Characteristics of participation were compared among the 3 different events in which surveys were conducted using the Pearson χ2 test and F test as appropriate. The estimated participation at ASA increased from nearly 3,500 (ASA 1 to 4) to 12,520 (ASA 5). The number of events increased to 3 per year for a total of 10 events until 2014. Overall, 19.4% of participants met the weekly PA recommendation during 1 event. The expanding diversity of routes, participants, and sponsorships highlights the potential promise such programming offers in terms of establishing an urban culture of health.
[Statins and ASS for primary prevention of cardiovascular and cerebrovascular disease].
Goltz, L; Bodechtel, U; Siepmann, T
2014-02-01
Whereas statins and acetylsalicylic acid (ASA) are considered gold standard for secondary prevention following myocardial infarction or atherotrombotic stroke, there are inconsistent data on the use of these drugs for primary prevention in patients with increased cardiovascular risk. Some meta-analyses indicated that the use of statins and ASA for primary prevention of cardiovascular disease can reduce the risk of cardiovascular events such as ischemic stroke or myocardial infarction. However, the effects of primary prevention with statins and ASA on mortality varied in the data included in these meta-analyses. Therefore the guidelines of the German College of General Practitioners and Family Physicians recommend primary prevention with statins and ASA only in those patients who have a 10-year risk of cardiovascular events which exceeds 20 %. Divergently, primary prevention with ASA is not recommended by the European Society of Cardiology. Observational studies suggested that treatment success of primary prevention with statins and ASA depends on various factors such as adherence to medication and prescription behavior of physicians. This review summarizes the current literature on primary prevention of cardiovascular events with ASA and statins. © Georg Thieme Verlag KG Stuttgart · New York.
Kim, Myeong-Ok; Choe, Min Ho; Yoon, Yi Na; Ahn, Jiyeon; Yoo, Minjin; Jung, Kwan-Young; An, Sungkwan; Hwang, Sang-Gu; Oh, Jeong Su; Kim, Jae-Sung
2017-11-15
Protein phosphatase 2A (PP2A) is a critical tumor suppressor complex responsible for the inactivation of various oncogenes. Recently, PP2A reactivation has emerged asan anticancer strategy. Cancerous inhibitor of protein phosphatase 2A (CIP2A), an endogenous inhibitor of PP2A, is upregulated in many cancer cells, including non-small cell lung cancer (NSCLC) cells. We demonstrated that the antihelminthic drug niclosamide inhibited the expression of CIP2A and reactivated the tumor suppressor PP2A in NSCLC cells. We performed a drug-repurposing screen and identified niclosamide asa CIP2A suppressor in NSCLC cells. Niclosamide inhibited cell proliferation, colony formation, and tumor sphere formation, and induced mitochondrial dysfunction through increased mitochondrial ROS production in NSCLC cells; however, these effects were rescued by CIP2A overexpression, which indicated that the antitumor activity of niclosamide was dependent on CIP2A. We found that niclosamide increased PP2A activity through CIP2A inhibition, which reduced the phosphorylation of several oncogenic proteins. Moreover, we found that a niclosamide analog inhibited CIP2A expression and increased PP2A activity in several types of NSCLC cells. Finally, we showed that other well-known PP2A activators, including forskolin and FTY720, did not inhibit CIP2A and that their activities were not dependent on CIP2A. Collectively, our data suggested that niclosamide effectively suppressed CIP2A expression and subsequently activated PP2A in NSCLC cells. This provided strong evidence for the potential use of niclosamide asa PP2A-activating drug in the clinical treatment of NSCLC. Copyright © 2017 Elsevier Inc. All rights reserved.
Basophil responsiveness and clinical picture of acetylsalicylic acid intolerance.
Korosec, Peter; Mavsar, Nusa; Bajrovic, Nissera; Silar, Mira; Mrhar, Ales; Kosnik, Mitja
2011-01-01
Exposure to acetylsalicylic acid (ASA) may exacerbate respiratory or skin diseases or induce anaphylactoid reactions in apparently healthy individuals. We wanted to evaluate specific responsiveness of basophils to ASA in correlation with the clinical picture. We performed a prospective single-blind study of 59 subjects involved in clinical evaluation and/or ASA provocation testing. Whole blood basophils were stained with anti-CD63/CD123/HLA-DR mAbs after stimulation with 0.25 or 1 mg/ml ASA. We found that 40 subjects were ASA tolerant and 19 were ASA intolerant. Both groups had comparable manifestations of asthma and/or rhinitis (13 in the tolerant and 9 in the intolerant group). Intolerant subjects showed significantly higher basophil responsiveness to ASA in comparison to tolerant subjects, which was concentration-dependent in both groups. The ratio between responses at 1 mg/ml of ASA and at baseline (activation index) was analyzed according to the clinical picture. We demonstrate that the activation index was higher only in the intolerant subjects with anaphylactoid reactions, but not in a subgroup of subjects with asthma/rhinitis. The ROC calculations show that the optimal threshold activation index was more than 2.18. The sensitivity was 80% and the specificity was 83% in the subgroup with anaphylactoid reactions. In the asthma/rhinitis subgroup, the sensitivity was 78% and the specificity was 50%. Our study demonstrates that there is a significantly higher in vitro basophil response to ASA in intolerant as compared to tolerant subjects. ROC analyses suggest that this measurement might only have a diagnostic value in subjects without asthma and/or rhinitis. Copyright © 2011 S. Karger AG, Basel.
Schwarz, K B; Arey, B J; Tolman, K; Mahanty, S
1988-01-01
To investigate the possibility that lipid peroxidation is the mechanism responsible for aspirin-induced liver damage, pure neutralized acetylsalicylic acid (ASA), 0.6-90.9 mM, was added to calcium-aggregated mouse liver microsomes followed by incubation in NADPH buffer at 37 degrees C for 60 min and subsequent measurement of malondialdehyde (MDA). MDA production at ASA concentrations from 1.2 to 4.6 mM was greater than control (P less than 0.004). Peak MDA values were observed with 4.6 mM ASA, 39.58 +/- 6.73 nmol MDA/mg protein vs. 16.16 +/- 2.85 (P less than 0.004). Higher concentrations of ASA were inhibitory compared with the value at 4.6 mM (P less than 0.001). Aspirin had similar effects on MDA production by mouse liver mitochondria. MDA production with either ASA or buffer was completely suppressed by the potent iron-chelating agents desferrioxamine and alpha,alpha' dipyridyl when these were added to the microsomal preparations. Since MDA production in this system is known to be affected by iron-chelating agents (enhanced at low concentration, inhibited at higher concentration), the iron-chelating properties of ASA were investigated. Conductivity titration curves of Fe(OH)3 added to water or ASA suggested that the ASA was complexing with iron. The presence of an iron-ASA complex was established by high pressure liquid chromatographic analysis of the solution from this study. We conclude that aspirin enhances MDA production by hepatic microsomes and mitochondria via an aspirin-iron chelate and that this represents at least one mechanism by which aspirin may produce liver damage. PMID:3335633
Li, Suqi; Xu, Jing; Chen, Wei; Yu, Yingtan; Liu, Zizheng; Li, Jinjun; Wu, Feng
2016-09-01
p-Arsanilic acid (p-ASA) is widely used in China as livestock and poultry feed additive for promoting animal growth. The use of organoarsenics poses a potential threat to the environment because it is mostly excreted by animals in its original form and can be transformed by UV-Vis light excitation. This work examined the initial rate and efficiency of p-ASA phototransformation under UV-C disinfection lamp. Several factors influencing p-ASA phototransformation, namely, pH, initial concentration, temperature, as well as the presence of NaCl, NH4(+), and humic acid, were investigated. Quenching experiments and LC-MS were performed to investigate the mechanism of p-ASA phototransformation. Results show that p-ASA was decomposed to inorganic arsenic (including As(III) and As(V)) and aromatic products by UV-C light through direct photolysis and indirect oxidation. The oxidation efficency of p-ASA by direct photosis was about 32%, and those by HO and (1)O2 were 19% and 49%, respectively. Cleavage of the arsenic-benzene bond through direct photolysis, HO oxidation or (1)O2 oxidation results in simultaneous formation of inorganic As(III), As(IV), and As(V). Inorganic As(III) is oxidized to As(IV) and then to As(V) by (1)O2 or HO. As(IV) can undergo dismutation or simply react with oxygen to produce As(V) as well. Reactions of the organic moieties of p-ASA produce aniline, aminophenol and azobenzene derivatives as main products. The photoconvertible property of p-ASA implies that UV disinfection of wastewaters from poultry and swine farms containing p-ASA poses a potential threat to the ecosystem, especially agricultural environments. Copyright © 2016. Published by Elsevier B.V.
Kanazawa, H; Fujimoto, S; Ohara, A
1994-04-01
Incubation of papain (EC 3.4.22.2) with ascorbic acid (AsA) and Cu2+ in acetate buffer (pH 5.6) results in an irreversible loss of enzyme activity by site-specific generation of free radicals [H. Kanazawa, S. Fujimoto, A. Ohara, Biol. Pharm.Bull., 16, 11 (1993)]. In this study, the effect of some compounds, known free radical scavengers, on the relationship between the inactivation of papain by the Cu(2+)-AsA system and the oxidation of AsA was investigated. Catalase completely protected the enzyme from inactivation by the Cu(2+)-AsA system, although hydrogen peroxide (H2O2) by itself, known to be generated during the autoxidation of AsA, did not inactivate the enzyme. The oxidation of AsA was unaffected by catalase. Both thiourea and sodium thiocyanate completely protected the enzyme from inactivation, while AsA was partially oxidized only in the initial stage. In the presence of potassium iodide, both the inactivation of the enzyme and the oxidation of AsA were characterized by a rapid initial phase followed by a stable phase where no reaction took place and, subsequently, a slower phase. Histidine partially prevented the inactivation of the enzyme and the oxidation of AsA. The present results suggest that H2O2 serves as a source of secondary, highly reactive species, probably hydroxyl radicals, which are responsible for the inactivation, and that the protection from inactivation by some radical scavengers, such as thiourea, sodium thiocyanate, potassium iodide, and histidine, is based on the removal of metal ions (Cu2+ or Cu+) at the specific site of inactivation.
Synergic carcinostatic effects of ascorbic acid and hyperthermia on Ehrlich ascites tumor cell.
Saitoh, Y; Yoshimoto, T; Kato, S; Miwa, N
2015-06-01
In this study, we evaluated the carcinostatic effects of combined ascorbic acid (AsA) and a capacitive-resistive electric transfer (CRet) hyperthermic apparatus-induced hyperthermic treatment on Ehrlich ascites tumor (EAT) cells. EAT cells were exposed to various AsA (0-10 mM) concentrations for 1 h; they subsequently underwent CRet treatment for 15 min at 42 °C. Cell viability was assessed by the WST-8 assay 24 h after the combined treatment. Reactive oxygen species involvement was evaluated using catalase and tempol; caspase-3/7 activation was determined by their fluorescent substrates; cell proliferation were estimated by time-lapse observation. The effect on the cell cycle was analyzed by flow cytometry. Combined AsA and CRet treatment synergistically suppressed cell viability compared with either treatment alone, and these synergistically carcinostatic effects were evident even at noncytotoxic concentrations of AsA alone (≤ 2 mM). The carcinostatic effects of combined AsA and CRet treatment were attenuated in a dose-dependent manner by catalase addition, but not by the superoxide anion radical scavenger tempol. Time-lapse observation revealed that combined AsA and CRet treatment activated caspase-3/7 at 10-24 h after treatment, accompanied by significant cell growth suppression. Cell cycle analysis revealed that the rate of sub-G1-phase (apoptotic) cells was drastically increased at 12 h and 24 h, and that the G2/M-phase cells gradually increased at 6-24 h after treatment. These results indicate that combined AsA and CRet treatment synergistically inhibits EAT cell growth through G2/M arrest and apoptosis induction via H2O2 generation at lower AsA concentrations; this carcinostatic effect cannot be exerted by AsA alone.
Burkholder, Greer A; Tamhane, Ashutosh R; Salinas, Jorge L; Mugavero, Michael J; Raper, James L; Westfall, Andrew O; Saag, Michael S; Willig, James H
2012-12-01
Individuals infected with human immunodeficiency virus (HIV) are at increased risk for cardiovascular disease (CVD) events compared with uninfected persons. However, little is known about HIV provider practices regarding aspirin (ASA) for primary prevention of CVD. A cross-sectional study was conducted among patients attending the University of Alabama at Birmingham 1917 HIV Clinic during 2010 to determine the proportion receiving ASA for primary prevention of CVD and identify factors associated with ASA prescription. Ten-year risk for CVD events was calculated for men aged 45-79 and women aged 55-79. The 2009 US Preventive Services Task Force (USPSTF) guidelines were used to determine those qualifying for primary CVD prevention. Among 397 patients who qualified to receive ASA (mean age, 52.2 years, 94% male, 36% African American), only 66 (17%) were prescribed ASA. In multivariable logistic regression analysis, diabetes mellitus (odds ratio [OR], 2.60; 95% confidence interval [CI], 1.28-5.27), hyperlipidemia (OR, 3.42; 95% CI, 1.55-7.56), and current smoking (OR, 1.87; 95% CI, 1.03-3.41) were significantly associated with ASA prescription. Odds of ASA prescription more than doubled for each additional CVD-related comorbidity present among hypertension, diabetes, hyperlipidemia, and smoking (OR, 2.13, 95% CI, 1.51-2.99). In this HIV-infected cohort, fewer than 1 in 5 patients in need received ASA for primary CVD prevention. Escalating likelihood of ASA prescription with increasing CVD-related comorbidity count suggests that providers may be influenced more by co-occurrence of these diagnoses than by USPSTF guidelines. In the absence of HIV-specific guidelines, interventions to improve HIV provider awareness of and adherence to existing general population guidelines on CVD risk reduction are needed.
Spencer, Frederick A; Santopinto, Jose J; Gore, Joel M; Goldberg, Robert J; Fox, Keith A A; Moscucci, Mauro; White, Kami; Gurfinkel, Enrique P
2002-11-15
The long-term use of aspirin (ASA) reduces the risk of subsequent acute coronary syndromes in patients with coronary artery disease (CAD). It is less clear whether ASA therapy benefits patients who develop an acute coronary syndrome despite its use. Baseline characteristics, type of acute coronary syndrome, and in-hospital events were compared on the basis of previous use of ASA in 11,388 patients with and without a history of CAD presenting to 94 multinational hospitals. A total of 73.0% of patients with a history of CAD (n = 4,974) were previously on long-term ASA therapy compared with 19.4% of patients without a history of CAD (n = 6,414). After multivariate regression analysis controlling for various potentially confounding factors, patients with a history of CAD who were previously taking ASA were significantly less likely to present with ST-segment elevation myocardial infarction (MI) (adjusted odds ratio [OR] 0.52, 95% confidence intervals [CI] 0.44 to 0.61) or die during hospitalization (OR 0.69, 95% CI 0.50 to 0.95) in comparison to patients who were not taking ASA. Patients without a history of CAD and who were previously taking ASA also had a lower risk of developing ST-segment elevation MI (OR 0.35, 95% CI 0.30 to 0.40) and a trend toward a decreased hospital death rate (OR 0.77, 95% CI 0.55 to 1.07). These results demonstrate that patients with a history of CAD who present with an acute coronary syndrome despite prior ASA use have less severe clinical presentation, fewer hospital complications, and lower in-hospital death rates than patients not previously taking ASA.
Jiang, Yumei; Cui, Dong; Du, Yuefeng; Lu, Jun; Yang, Lin; Li, Jinmei; Zhang, Jing; Bai, Xiaojing
2016-11-01
Chronic prostatitis is a risk factor for impaired male fertility potential, and anti-sperm antibodies (ASAs) cause the autoimmune disease immune infertility, which has a negative effect on semen parameters. Current studies have investigated the ASA-positive relationship between chronic prostatitis versus normal controls, but have shown inconsistent results. Hence, we systematic searched the PubMed, EMBASE, Science Direct/Elsevier, Medline, and the Cochrane Library up to October 2015 for case-control studies that involved the ASA-positive relationship between chronic prostatitis patients versus normal controls. The meta-analysis was performed with Review Manager and Stata software. After literature search, six studies were identified, including 721 cases of chronic prostatitis and 160 normal controls. Our results illustrated a significant correlation of the ASA-positive relationship between chronic prostatitis patients versus normal controls. The combined odds ratio of the ASA-positive rate in chronic prostatitis patients and normal controls was 3.26 (1.86-5.71). There was also a significant correlation of the ASA-positive relationship between National Institutes of Health (NIH) III versus normal controls, and the combined OR was 2.46 (1.10-5.51). However, there was no significant correlation of the ASA-positive relationship between National Institutes of Health (NIH) II versus normal controls. The present study illustrates that the positive rate of ASAs in chronic prostatitis patients was significantly higher than in the control group, suggesting that chronic prostatitis has a negative effect on male reproductive function. However, studies with larger samples are needed to better illuminate the correlation between ASAs and chronic prostatitis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Madariaga-Venegas, Francisco; Fernández-Soto, Roberto; Duarte, Luisa Fernanda; Suarez, Nicole; Delgadillo, Daniela; Jara, José A.; Fernández-Ramires, Ricardo; Urzúa, Blanca; Molina-Berríos, Alfredo
2017-01-01
Candida albicans biofilms play a key role in denture stomatitis, one of the most common oral pathologies in elderly people. Because biofilms are highly resistant to antifungals, new pharmacological strategies are needed. Aspirin and nitric oxide-donor molecules have both shown antibiofilm effects on C. albicans, making them promising candidates for treatment. In this study, we evaluated the antifungal/antibiofilm effect of a nitric-oxide releasing aspirin (NO-ASA) on C. albicans isolates from denture stomatitis patients in vitro. Disk diffusion assays showed that while NO-ASA had no antifungal effect, the drug potentiated fluconazole inhibition zone diameters, increasing the effect of fluconazole by 20–30% (p<0.05). The effect of NO-ASA on the morphogenesis of C. albicans was evaluated using light microscopy after inducing hyphae formation. For all clinical strains assayed, 125 μM NO-ASA significantly decreased the number of filamentous cells present (p<0.01). Adhesion to abiotic surfaces, a critical event for biofilm formation, was evaluated in 96-well polystyrene plates using crystal violet assay; 125 μM NO-ASA significantly inhibited adhesion. Biofilms were observed with scanning electron microscopy (SEM) and quantified using XTT reduction assay. NO-ASA decreased biofilm formation (IC50 ranging from 300 μM to 700 μM), consistent with SEM findings of altered biofilm microarchitecture. PGE2 and carboxy-PTIO (an NO scavenger) both blocked the antibiofilm effects of NO-ASA, suggesting that the efficacy of NO-ASA may be associated with both inhibition of PGE2 synthesis and release of NO. NO-ASA is a promising novel antibiofilm agent for treating fluconazole-resistant strains of C. albicans. PMID:28493889
Antolovic, D; Rakow, A; Contin, P; Ulrich, A; Rahbari, N N; Büchler, M W; Weitz, J; Koch, M
2012-02-01
Surgeons are increasingly confronted by patients on long-term low-dose acetylsalicylic acid (ASA). However, owing to a lack of evidence-based data, a widely accepted consensus on the perioperative management of these patients in the setting of non-cardiac surgery has not yet been reached. Primary objective was to evaluate the safety of continuous versus discontinuous use of ASA in the perioperative period in elective general or abdominal surgery. Fifty-two patients undergoing elective cholecystectomy, inguinal hernia repair or colonic/colorectal surgery were recruited to this pilot study. According to cardiological evaluation, non-high-risk patients who were on long-term treatment with low-dose ASA were eligible for inclusion. Patients were allocated randomly to continuous use of ASA or discontinuation of ASA intake for 5 days before until 5 days after surgery. The primary outcome was the incidence of major haemorrhagic and thromboembolic complications within 30 days after surgery. A total of 26 patients were allocated to each study group. One patient (3.8%) in the ASA continuation group required re-operation due to post-operative haemorrhage. In neither study group, further bleeding complications occurred. No clinically apparent thromboembolic events were reported in the ASA continuation and the ASA discontinuation group. Furthermore, there were no significant differences between both study groups in the secondary endpoints. Perioperative intake of ASA does not seem to influence the incidence of severe bleeding in non-high-risk patients undergoing elective general or abdominal surgery. Further, adequately powered trials are required to confirm the findings of this study.
Bruder, Markus; Won, Sae-Yeon; Wagner, Marlies; Brawanski, Nina; Dinc, Nazife; Kashefiolasl, Sepide; Seifert, Volker; Konczalla, Juergen
2018-05-01
Demographic changes are leading to an aging society with a growing number of patients with cardiovascular diseases, relying on antiplatelet drugs like acetylsalicylic acid (ASA). Although antiplatelet agents are suspected to be protective not only in the cardiologic but in the neurovascular field, the alteration of the coagulating process could have a major impact on the course and outcome after rupture of intracranial aneurysms. Between June 1999 and December 2014, 1422 patients were treated for aneurysmal SAH in our institution, 144 (10.1%) with continuous ASA at the time of aneurysm rupture. A matched-pair analysis was performed. The rate of patients with continuous ASA treatment while rupture of the aneurysm is rising significantly (P < 0.01). Those patients were significantly older than patients without ASA (60 vs. 53 years, P < 0.001). ASA-treated patients more often had aneurysmal rebleeding (4.7% vs. 2.3%, P = 0.3) and treatment-related hemorrhagic complications (13.9% vs. 6.2%, P = 0.06). However, rates were not different in microsurgical or endovascular procedures (16.4% vs. 12.2%, P = 0.6). Favorable outcome (Modified Rankin Scale 0-2) was achieved in 49.3% of the ASA group and 52.1% of the control group (P = 0.7). Patients with continuous ASA treatment were significantly older than patients without ASA, but there was no difference in admission status or bleeding pattern. Outcome was not different in the matched-pair analysis. There was no statistical difference in treatment related-complication rates of microsurgical and endovascular procedures. Therefore, ASA use should not influence treatment decision of the ruptured aneurysm. Copyright © 2018 Elsevier Inc. All rights reserved.
5-Aminosalicylic acid and chemoprevention: does it work?
Lopez, Anthony; Peyrin-Biroulet, Laurent
2013-01-01
5-Aminosalicylic acid (5-ASA)-containing drugs are the mainstay of therapy in inflammatory bowel disease (IBD). Intestinal inflammation is the main risk factor for colorectal cancer (CRC) in IBD. Hence, all drugs that are able to induce and maintain mucosal healing (MH) may prevent CRC risk in IBD. In patients with mild to moderate ulcerative colitis (UC), a recent systematic review of 5-ASA trials demonstrated that MH was achieved in nearly 50% of patients. A systematic review including 48 studies linked 5-ASA chemopreventive properties to five distinct pathways: cell cycle progression, scavenging of reactive oxygen- or nitrogen-derived metabolites, TNF-α/TGF-ss signaling, WNT/β-catenin signaling and antibacterial properties. Therefore, in addition to their overall anti-inflammatory activity on the intestinal mucosa, 5-ASA compounds have specific effects on colorectal carcinogenesis at the molecular level. In 2005, a landmark meta-analysis of observational studies found a protective association between 5-ASA and CRC or a combined end point of CRC/dysplasia in UC patients. More recently, a meta-analysis failed to identify a protective effect of 5-ASA on CRC risk in non-referral populations, but in a separate analysis of 9 clinic-based studies, the pooled odds ratio was 0.58 (95% confidence interval: 0.45-0.75), further highlighting the chemopreventive effect of 5-ASA on CRC risk. In conclusion, 5-ASA therapy may reduce CRC risk by healing the mucosa of UC patients and via specific mechanisms of action at the molecular level. Conducting a clinical trial providing the best level of evidence by comparing UC patients receiving 5-ASA treatment versus those included in a placebo arm would be unethical. © 2013 S. Karger AG, Basel.
Madariaga-Venegas, Francisco; Fernández-Soto, Roberto; Duarte, Luisa Fernanda; Suarez, Nicole; Delgadillo, Daniela; Jara, José A; Fernández-Ramires, Ricardo; Urzúa, Blanca; Molina-Berríos, Alfredo
2017-01-01
Candida albicans biofilms play a key role in denture stomatitis, one of the most common oral pathologies in elderly people. Because biofilms are highly resistant to antifungals, new pharmacological strategies are needed. Aspirin and nitric oxide-donor molecules have both shown antibiofilm effects on C. albicans, making them promising candidates for treatment. In this study, we evaluated the antifungal/antibiofilm effect of a nitric-oxide releasing aspirin (NO-ASA) on C. albicans isolates from denture stomatitis patients in vitro. Disk diffusion assays showed that while NO-ASA had no antifungal effect, the drug potentiated fluconazole inhibition zone diameters, increasing the effect of fluconazole by 20-30% (p<0.05). The effect of NO-ASA on the morphogenesis of C. albicans was evaluated using light microscopy after inducing hyphae formation. For all clinical strains assayed, 125 μM NO-ASA significantly decreased the number of filamentous cells present (p<0.01). Adhesion to abiotic surfaces, a critical event for biofilm formation, was evaluated in 96-well polystyrene plates using crystal violet assay; 125 μM NO-ASA significantly inhibited adhesion. Biofilms were observed with scanning electron microscopy (SEM) and quantified using XTT reduction assay. NO-ASA decreased biofilm formation (IC50 ranging from 300 μM to 700 μM), consistent with SEM findings of altered biofilm microarchitecture. PGE2 and carboxy-PTIO (an NO scavenger) both blocked the antibiofilm effects of NO-ASA, suggesting that the efficacy of NO-ASA may be associated with both inhibition of PGE2 synthesis and release of NO. NO-ASA is a promising novel antibiofilm agent for treating fluconazole-resistant strains of C. albicans.
Cortellini, G; Romano, A; Santucci, A; Barbaud, A; Bavbek, S; Bignardi, D; Blanca, M; Bonadonna, P; Costantino, M T; Laguna, J J; Lombardo, C; Losappio, L M; Makowska, J; Nakonechna, A; Quercia, O; Pastorello, E A; Patella, V; Terreehorst, I; Testi, S; Cernadas, J R; Dionicio Elera, J; Lippolis, D; Voltolini, S; Grosseto, D
2017-03-01
Hypersensitivity to acetylsalicylic acid (ASA) constitutes a serious problem for subjects with coronary artery disease. In such subjects, physicians have to choose the more appropriate procedure between challenge and desensitization. As the literature on this issue is sparse, this study aimed to establish in these subjects clinical criteria for eligibility for an ASA challenge and/or desensitization. Collection and analysis of data on ASA challenges and desensitizations from 10 allergy centers, as well as consensus among the related physicians and an expert panel. Altogether, 310 subjects were assessed; 217 had histories of urticaria/angioedema, 50 of anaphylaxis, 26 of nonimmediate cutaneous eruptions, and 17 of bronchospasm related to ASA/nonsteroidal anti-inflammatory drugs (NSAID) intake. Specifically, 119 subjects had index reactions to ASA doses lower than 300 mg. Of the 310 subjects, 138 had an acute coronary syndrome (ACS), 101 of whom underwent desensitizations, whereas 172 suffered from a chronic ischemic heart disease (CIHD), 126 of whom underwent challenges. Overall, 163 subjects underwent challenges and 147 subjects underwent desensitizations; 86 of the latter had index reactions to ASA doses of 300 mg or less. Ten subjects reacted to challenges, seven at doses up to 500 mg, three at a cumulative dose of 110 mg. The desensitization failure rate was 1.4%. In patients with stable CIHD and histories of nonsevere hypersensitivity reactions to ASA/NSAIDs, an ASA challenge is advisable. Patients with an ACS and histories of hypersensitivity reactions to ASA, especially following doses lower than 100 mg, should directly undergo desensitization. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Caffeic acid phenethyl ester protects kidneys against acetylsalicylic acid toxicity in rats.
Bozkurt, Yasar; Bozkurt, Mehtap; Turkçu, Gul; Sancaktutar, Ahmet Ali; Soylemez, Haluk; Penbegul, Necmettin; Atar, Murat; Bodakcı, Mehmet Nuri; Hatipoglu, Namık Kemal; Yuksel, Hatice; Kıbrıslı, Erkan; Yavuz, Celal
2012-01-01
The aim of this study was to investigate the protective effect of caffeic acid phenethyl ester (CAPE) on acetylsalicylic acid (ASA)-induced renal damage in rats. A total of 40 rats were randomly divided into five groups, with eight rats in each group-group 1: control, not receiving any medication; group 2: ASA (50 mg/kg/day); group 3: ASA (50 mg/kg/day) + CAPE (20 μg/kg/day); group 4: ASA (100 mg/kg/day); and group 5: ASA (100 mg/kg/day) + CAPE (20 μg/kg/day). ASA and CAPE were given via orogastric gavage for 5 days. The total oxidant status (TOS), total antioxidant capacity (TAC), and paraoxonase-1 (PON-1) activity of the blood samples and kidney tissues were determined. Histopathological examinations of the kidneys were performed using light microscopic methods. The TOS level in the serum of rats and kidney tissues given ASA (groups 2 and 4) significantly increased, but the levels of TAC and PON-1 in these tissues significantly decreased in group 4 when compared with the control rats (p < 0.05). The levels of TAC and PON-1 in the kidney tissues increased and the levels of TOS decreased in the CAPE treatment groups (groups 3 and 5) when compared with the rats in the no CAPE treatment groups (groups 2 and 4). The PON-1, TAC, and TOS values reverted to normal levels in group 5 when compared to group 4 (p < 0.05). These results were supported by histopathological observation. Oxidative stress plays an important role in ASA-induced nephrotoxicity, and CAPE may protect against ASA-induced nephrotoxicity in rats.
NASA Astrophysics Data System (ADS)
Mao, Zepeng; Zhang, Jun
2018-06-01
The phase morphology of two elastomers (i.e., chlorinated polyethylene (CPE) and polybutadiene rubber (BR)) were devised to be a core-shell structure in acrylonitrile-styrene-acrylate (ASA) resin matrix, via the interfacial tension differences of polymer pairs. Selective extraction test and scanning electron microscopy (SEM) were utilized to verify this special phase morphology. The results demonstrated that the core-shell structure, BR core and CPE shell, significantly contributed to improve the low temperature toughness of ASA/CPE/BR ternary blends, which may be because the nonpolar BR core was segregated from polar ASA by the CPE shell. The CPE shell served dual functions: Not only did it play compatibilizing effect in the interface between BR and ASA matrix, but it also toughened the blends at 25 and 0 °C. The blends of ASA/CPE/BR (100/27/3, w/w/w) and ASA/CPE/BR (100/22/8, w/w/w) showed the peak impact strengths at about 28 and 9 kJ/m2 at 0 and -30 °C, respectively, which were higher than both that of ASA/CPE/BR (100/30/0, w/w/w) and ASA/CPE/BR (100/0/30, w/w/w). Moreover, the impact strength of ternary blends at room temperature kept at 40 kJ/m2 when BR content was lower than 10 phr. Other characterizations including contact angle measurement, dynamic mechanical thermal analysis (DMTA), morphology of impact-fractured surfaces, tensile properties, flexural properties, and Fourier transform infrared spectroscopy (FTIR) were measured as well.
Outer-sphere Pb(II) adsorbed at specific surface sites on single crystal α-alumina
Bargar, John R.; Towle, Steven N.; Brown, Gordon E.; Parks, George A.
1996-01-01
Solvated Pb(II) ions were found to adsorb as structurally well-defined outer-sphere complexes at specific sites on the α-Al2O3 (0001) single crystal surface, as determined by grazing-incidence X-ray absorption fine structure (GI-XAFS) measurements. The XAFS results suggest that the distance between Pb(II) adions and the alumina surface is approximately 4.2 Å. In contrast, Pb(II) adsorbs as more strongly bound inner-sphere complexes on α-Al2O3 (102). The difference in reactivities of the two alumina surfaces has implications for modeling surface complexation reactions of contaminants in natural environments, catalysis, and compositional sector zoning of oxide crystals.
Maxwell's second- and third-order equations of transfer for non-Maxwellian gases
NASA Technical Reports Server (NTRS)
Baganoff, D.
1992-01-01
Condensed algebraic forms for Maxwell's second- and third-order equations of transfer are developed for the case of molecules described by either elastic hard spheres, inverse-power potentials, or by Bird's variable hard-sphere model. These hardly reduced, yet exact, equations provide a new point of origin, when using the moment method, in seeking approximate solutions in the kinetic theory of gases for molecular models that are physically more realistic than that provided by the Maxwell model. An important by-product of the analysis when using these second- and third-order relations is that a clear mathematical connection develops between Bird's variable hard-sphere model and that for the inverse-power potential.
A data base of ASAS digital imagery. [Advanced Solid-state Array Spectroradiometer
NASA Technical Reports Server (NTRS)
Irons, James R.; Meeson, Blanche W.; Dabney, Philip W.; Kovalick, William M.; Graham, David W.; Hahn, Daniel S.
1992-01-01
The Advanced Solid-State Array Spectroradiometer (ASAS) is an airborne, off-nadir tilting, imaging spectroradiometer that acquires digital image data for 29 spectral bands in the visible and near-infrared. The sensor is used principally for studies of the bidirectional distribution of solar radiation scattered by terrestial surfaces. ASAS has acquired data for a number of terrestial ecosystem field experiments and investigators have received over 170 radiometrically corrected, multiangle, digital image data sets. A database of ASAS digital imagery has been established in the Pilot Land Data System (PLDS) at the NASA/Goddard Space Flight Center to provide access to these data by the scientific community. ASAS, its processed data, and the PLDS are described, together with recent improvements to the sensor system.
Asiago spectroscopic classification of ASAS-SN18ao
NASA Astrophysics Data System (ADS)
Tomasella, L.; Benetti, S.; Cappellaro, E.; Turatto, M.
2018-01-01
The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic classification of ASAS-SN18ao (aka AT2018gm, Atel #11178) discovered during the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014).
Rinehart, Jenny K; Yeater, Elizabeth A; Musci, Rashelle J; Letourneau, Elizabeth J; Lenberg, Kathryn L
2014-01-01
An experience of child sexual abuse (CSA) substantially increases women's risk of adult sexual assault (ASA), but the mechanisms underlying this relationship are unclear. Previous research often has not examined the full range of ASA experiences or included the influence of ethnicity, sexual behavior, and sexual attitudes on CSA and severity of ASA. The current study utilized path analysis to explore the relationships among ethnicity, sexual attitudes, number of lifetime sexual partners, CSA, and severity of ASA in emerging adult women. Results indicated a significant relationship between CSA and more severe ASA that was partially explained by having more lifetime sexual partners. Additionally, European American women, relative to Hispanic women, reported more severe victimization, which was fully explained by more positive attitudes toward casual sex and having more lifetime sexual partners. These results have implications in the design and implementation of universal and selective prevention programs aimed at reducing ASA and revictimization among emerging adult women. © The Author(s) 2014.
The ASAS-SN catalogue of variable stars I: The Serendipitous Survey
NASA Astrophysics Data System (ADS)
Jayasinghe, T.; Kochanek, C. S.; Stanek, K. Z.; Shappee, B. J.; Holoien, T. W.-S.; Thompson, Toda A.; Prieto, J. L.; Dong, Subo; Pawlak, M.; Shields, J. V.; Pojmanski, G.; Otero, S.; Britt, C. A.; Will, D.
2018-07-01
The All-Sky Automated Survey for Supernovae (ASAS-SN) is the first optical survey to routinely monitor the whole sky with a cadence of ˜2-3 d down to V ≲ 17 mag. ASAS-SN has monitored the whole sky since 2014, collecting ˜100-500 epochs of observations per field. The V-band light curves for candidate variables identified during the search for supernovae are classified using a random forest classifier and visually verified. We present a catalogue of 66 179 bright, new variable stars discovered during our search for supernovae, including 27 479 periodic variables and 38 700 irregular variables. V-band light curves for the ASAS-SN variables are available through the ASAS-SN variable stars data base (https://asas-sn.osu.edu/variables). The data base will begin to include the light curves of known variable stars in the near future along with the results for a systematic, all-sky variability survey.
Sexual Assault Disclosure and Sexual Functioning: The Role of Trauma Symptomatology.
Staples, Jennifer M; Eakins, Danielle; Neilson, Elizabeth C; George, William H; Davis, Kelly Cue; Norris, Jeanette
2016-10-01
Previous research has demonstrated that a history of adult sexual assault (ASA) is associated with negative outcomes, including trauma symptomatology and fear of sexual intimacy. Disclosing sexual assault might be protective against such negative outcomes. To examine the indirect effect of trauma symptomatology on the association between disclosing ASA and current sexual functioning. Participants included 652 women 21 to 30 years old with a history of ASA recruited from the community. Participants completed self-report measurements on a computer. Separate models were performed, with sexual functioning divided into sexual desire, orgasm, and pain during sex. ASA disclosure was indirectly associated with sexual orgasm and pain during sex by trauma symptomatology. However, there was no indirect effect of trauma symptomatology on the relation between ASA disclosure and sexual desire. Disclosing experiences of ASA could serve a protective function by lessening trauma symptomatology, thereby mitigating impacts on aspects of sexual functioning, such as orgasm and pain. Published by Elsevier Inc.
Aspirin Increases the Solubility of Cholesterol in Lipid Membranes
NASA Astrophysics Data System (ADS)
Alsop, Richard; Barrett, Matthew; Zheng, Sonbo; Dies, Hannah; Rheinstadter, Maikel
2014-03-01
Aspirin (ASA) is often prescribed for patients with high levels of cholesterol for the secondary prevention of myocardial events, a regimen known as the Low-Dose Aspirin Therapy. We have recently shown that Aspirin partitions in lipid bilayers. However, a direct interplay between ASA and cholesterol has not been investigated. Cholesterol is known to insert itself into the membrane in a dispersed state at moderate concentrations (under ~37.5%) and decrease fluidity of membranes. We prepared model lipid membranes containing varying amounts of both ASA and cholesterol molecules. The structure of the bilayers as a function of ASA and cholesterol concentration was determined using high-resolution X-ray diffraction. At cholesterol levels of more than 40mol%, immiscible cholesterol plaques formed. Adding ASA to the membranes was found to dissolve the cholesterol plaques, leading to a fluid lipid bilayer structure. We present first direct evidence for an interaction between ASA and cholesterol on the level of the cell membrane.
Schonberger, Robert B; Dutton, Richard P; Dai, Feng
2016-01-01
Modifications in physician billing patterns have been shown to occur in response to payer incentives, but the phenomenon remains largely unexplored in billing for anesthesia services. Within the field of anesthesiology, Medicare's policy not to provide additional reimbursement for higher ASA physical status scores contrasts with the practices of most private payers, and this pattern of reimbursement introduces a change in billing incentives once patients attain Medicare eligibility. We hypothesized that, coincident with the onset of widespread Medicare eligibility at age 65 years, a discontinuity in reported ASA physical status scores would be observed after controlling for the underlying trend of increasing ASA physical status scores with age. This phenomenon would manifest as a pattern of upcoding of ASA physical status scores for patients younger than 65 years that would become less common in patients age 65 years and older. Using data on age, sex, ASA physical status scores, and type of surgery from the National Anesthesia Clinical Outcomes Registry, we used a quasi-experimental regression discontinuity design to analyze whether there was evidence for a discontinuity in reported ASA physical status scores occurring at age 65 years for the nondeferrable anesthesia services accompanying hip, femur, or lower leg fracture repair. A total of 49,850 records were analyzed. In models designed to detect regression discontinuity at 65 years of age, neither the binary variable "age ≥ 65" nor the interaction term of age × age ≥ 65 was a statistically significant predictor of the outcome of ASA physical status score. The statistical inference was unchanged when ASA physical status scores were reclassified as a binary outcome (I-II vs III-V) and when different bandwidths around age 65 years were used. To test the validity of our study design for detecting regression discontinuity, simulations of the occurrence of deliberate upcoding of ASA physical status scores demonstrated the ability to detect deliberate upcoding occurring at rates exceeding 2% of eligible cases of patients younger than 65 years. We found no evidence for a significant discontinuity in the pattern of ASA physical status scores coincident with Medicare eligibility at age 65 years for the nondeferrable conditions of hip, femur, or lower leg fracture repair. Our data do not support the presence of fraudulent ASA physical status scoring among National Anesthesia Clinical Outcomes Registry contributors. If deliberate upcoding of ASA physical status scores is present in our data, the behavior is either too rare or too insensitive to the removal of payer incentives at age 65 years to be evident in the present analysis.
Application of semiclassical and geometrical optics theories to resonant modes of a coated sphere.
Bambino, Túlio M; Breitschaft, Ana Maria S; Barbosa, Valmar C; Guimarães, Luiz G
2003-03-01
This work deals with some aspects of the resonant scattering of electromagnetic waves by a metallic sphere covered by a dielectric layer, in the weak-absorption approximation. We carry out a geometrical optics treatment of the scattering and develop semiclassical formulas to determine the positions and widths of the system resonances. In addition, we show that the mean lifetime of broad resonances is strongly dependent on the polarization of the incident light.
Light-scattering efficiency of starch acetate pigments as a function of size and packing density.
Penttilä, Antti; Lumme, Kari; Kuutti, Lauri
2006-05-20
We study theoretically the light-scattering efficiency of paper coatings made of starch acetate pigments. For the light-scattering code we use a discrete dipole approximation method. The coating layer is assumed to consists of roughly equal-sized spherical pigments packed either at a packing density of 50% (large cylindrical slabs) or at 37% or 57% (large spheres). Because the scanning electron microscope images of starch acetate samples show either a particulate or a porous structure, we model the coatings in two complementary ways. The material can be either inside the constituent spheres (particulate case) or outside of those (cheeselike, porous medium). For the packing of our spheres we use either a simulated annealing or a dropping code. We can estimate, among other things, that the ideal sphere diameter is in the range 0.25-0.4 microm.
Light-scattering efficiency of starch acetate pigments as a function of size and packing density
NASA Astrophysics Data System (ADS)
Penttilä, Antti; Lumme, Kari; Kuutti, Lauri
2006-05-01
We study theoretically the light-scattering efficiency of paper coatings made of starch acetate pigments. For the light-scattering code we use a discrete dipole approximation method. The coating layer is assumed to consists of roughly equal-sized spherical pigments packed either at a packing density of 50% (large cylindrical slabs) or at 37% or 57% (large spheres). Because the scanning electron microscope images of starch acetate samples show either a particulate or a porous structure, we model the coatings in two complementary ways. The material can be either inside the constituent spheres (particulate case) or outside of those (cheeselike, porous medium). For the packing of our spheres we use either a simulated annealing or a dropping code. We can estimate, among other things, that the ideal sphere diameter is in the range 0.25-0.4 μm.
NASA Astrophysics Data System (ADS)
Carson, James K.
2018-06-01
Glass spheres are often used as filler materials for composites. Comparatively few articles in the literature have been devoted to the measurement or modelling of thermal properties of composites containing glass spheres, and there does not appear to be any reported data on the measurement of thermal diffusivities over a range of filler volume fractions. In this study, the thermal diffusivities of guar-gel/glass sphere composites were measured using a transient comparative method. The addition of the glass beads to the gel increased the thermal diffusivity of the composite, more than doubling the thermal diffusivity of the composite relative to the diffusivity of the gel at the maximum glass volume fraction of approximately 0.57. Thermal conductivities of the composites were derived from the thermal diffusivity measurements, measured densities and estimated specific heat capacities of the composites. Two approaches to modelling the effective thermal diffusivity were considered.
Sendur, Mehmet A N; Aksoy, Sercan; Ozdemir, Nuriye Y; Zengin, Nurullah; Altundag, Kadri
2014-04-01
The impact of acetylsalicylic acid (ASA) on the clinicopathological characteristics of breast cancer has not yet been elucidated in detail; we therefore aimed to investigate the effects of ASA on the clinicopathological characteristics of patients with breast cancer. Patients diagnosed with breast cancer were retrospectively analyzed. Breast cancer patients who were taking ASA at the time of breast cancer diagnosis were enrolled as ASA users (n = 84); matching patients with the same age who were not taking ASA were included as control group (n = 890). The median age was 56 (range 34-82) years in both groups. ASA users had a significantly lower incidence of grade II-III tumors compared to non-users (P = 0.02). The other clinicopathological characteristics and treatment histories were similar in both groups. In patients using ASA, the disease-free survival (DFS) rate was 97.3%, 89.4%, and 79.9% and in non-users it was 94.1%, 81.8%, and 70.9% in the 1rst, 3rd, and 5th year, respectively (P = 0.01). In aspirin users, the overall survival rate was 95.0%, 90.6%, and 87.6% and in non-users it was 98.1%, 91.2%, and 85.5% in the 1rst, 3rd, and 5th year, respectively (P = 0.50). Using ASA at the time of breast cancer diagnosis was associated with significantly improved DFS in breast cancer patients.
Kamble, Pratibha; Selvarajan, Krithika; Narasimhulu, Chandrakala Aluganti; Nandave, Mukesh; Parthasarathy, Sampath
2013-01-01
Based on the rapid hydrolysis of acetyl salicylic acid (ASA, Aspirin) to salicylic acid (SA), the ability of SA to form dihydroxy benzoic acid (DBA), and the latter’s redox reactions to yield hydrogen peroxide (H2O2), we predicted that ASA may have the potential to induce Sirtuin1 (Sirt1) and its downstream effects. We observed that treatment of cultured liver cells with ASA resulted in the induction of Sirt1, peroxisome proliferator-activated receptor-gamma co-activator-1α (PGC-1α), and NAD(P)H quinone oxidoreductase 1 (Nqo1) genes. Paraoxonase 1 (PON1) and Aryl hydrocarbon receptor (AhR) siRNA transfections inhibited the induction of gene expressions by ASA suggesting the need for the acetyl ester hydrolysis and hydroxylation to DHBA. The latter also induced Sirt1, confirming the proposed pathway. As predicted, ASA and SA treatment resulted in the production of H2O2, a known inducer of Sirt1 and confirmed in the current studies. More importantly, ASA treatment resulted in an increase in mitochondria as seen by tracking dyes. We suggest that DHBA, generated from ASA, via its oxidation/reduction reactions mediated by Nqo1 might be involved in the production of O2-. and H2O2. As Sirt1 and PGC-1α profoundly affect mitochondrial metabolism and energy utilization, ASA may have therapeutic potential beyond its ability to inhibit cyclooxygenases. PMID:23228932
Nizankowska, E; Dworski, R; Soja, J; Szczeklik, A
1990-11-01
Aspirin (ASA) and other non-steroidal anti-inflammatory drugs, which are cyclooxygenase (COX) inhibitors, precipitate asthmatic attacks in ASA-intolerant patients, while sodium salicylate, hardly active on COX by itself, is well tolerated by these patients. However, salicylate moiety appears to interfere with aspirin inhibitory action on platelets and vascular COX. Such interaction, if present at the level of respiratory tract, may be of interest to pathogenesis of ASA-induced asthma. We performed a double-blind, placebo-controlled, randomized cross-over study on the effect of choline magnesium trisalicylate (CMT, trilisate) pre-treatment on ASA-induced adverse reactions in nine patients. Pulmonary function tests, nasal symptoms score, PNIF and serum salicylate levels were monitored following challenges with threshold doses of ASA. Trilisate administered at a dose of 3000 mg daily for 3 days, offered a moderate protection against ASA-induced symptoms; it diminished the severity and/or delayed the appearance of FEV1 fall. Maximal decreases in FEV1 as well as reaction intensity indexes were significantly lower (P less than 0.02 and P less than 0.002, respectively) after trilisate pre-treatment as compared to placebo. Trilisate also attenuated nasal symptoms in three out of five patients. Although the precise mechanism of the protective action of trilisate is unknown, our data support the possibility of interaction between salicylate and ASA on cyclo-oxygenase locus in the respiratory tract in ASA-intolerant patients.
Danesh, B J; Nelson, L M; Russell, R I; Docherty, C
1987-02-01
The acetyl moiety in aspirin (acetyl salicylic acid: ASA) is considered to play a major part in the pathogenesis of ASA-induced mucosal injury. At equivalent salicylate doses and pH values, the induction of acute gastric mucosal haemorrhagic erosions in rats by ASA and choline magnesium trisalicylate (CMT), a new non-acetylated salicylate, with and without the potentiating damaging effect of taurodeoxycholic acid (TDCA) were compared. Test solutions were administered by per oral intubation to five groups of fasting Sprague-Dawley rats (n = 24). Gastric mucosa were examined after 4 hours and mucosal injury assessed by a lesion-scoring system. The incidence and severity (median lesion scores with quartiles) of the lesions were 83% and 13 (7:20) respectively for ASA (128 mg kg-1) compared with 17% and 0 (0:0) for CMT (128 mg kg-1) (P less than 0.001 and P less than 0.001). TDCA increased mucosal damage to 100% and 29 (20:34) for ASA compared with 30% and 0 (0:4) for CMT (P less than 0.001) and P less than 0.001). Serum salicylate levels (median values of 1.4 for ASA and 1.5 mmol litre-1 for CMT) were not significantly different. It is concluded that replacing the acetyl moiety in ASA with choline and magnesium moieties reduces the ASA-induced mucosal injury, without affecting blood salicylate concentrations.
78 FR 32477 - ASA Gold and Precious Metals Limited; Notice of Application
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-30
... strategy consistent with its current fundamental investment policy and to achieve its desired portfolio... approval of its shareholders, ASA replaced its fundamental investment policies that, among other things... SECURITIES AND EXCHANGE COMMISSION [Investment Company Act Release No. 30539; 812-13877] ASA Gold...
Nutrient and Food Group Analysis in the 2016 ASA24® System
Researchers, clinicians, and educators can use the ASA24 system to analyze 65 nutrients and 37 food groups (U.S. and Canadian versions) from food recall or record data. Analyses for ASA24-Australia-2016 provide 41 nutrients and no food groups.
NASA Technical Reports Server (NTRS)
Johnston, Christopher O.; Gnoffo, Peter A.; Mazaheri, Alireza
2013-01-01
A review of recently published coupled radiation and ablation capabilities involving the simulation of hypersonic flowfields relevant to Earth, Mars, or Venus entry is presented. The three fundamental mechanisms of radiation coupling are identified as radiative cooling, precursor photochemistry, and ablation-radiation interaction. The impact of these mechanisms are shown to be significant for a 3 m radius sphere entering Earth at hypothetical Mars return conditions (approximately 15 km/s). To estimate the influence precursor absorption on the radiative flux for a wide range of conditions, a simplified approach is developed that requires only the non-precursor solution. Details of a developed coupled ablation approach, which is capable of treating both massively ablating flowfields in the sublimation regime and weakly ablating diffusion Climited oxidation cases, are presented. A review of the two primary uncoupled ablation approximations, identified as the blowing correction and film coefficient approximations, is made and their impact for Earth and Mars entries is shown to be significant for recession and convective heating predictions. Fully coupled ablation and radiation simulations are presented for the Mars return sphere throughout its entire trajectory. Applying to the Mars return sphere the Pioneer- Venus heritage carbon phenolic heatshield, which has properties available in the open literature, the differences between steady state ablation and coupling to a material response code are shown to be significant.
Chong, Simon W; Collins, Neil F; Wu, Christine Y; Liskaser, Grace M; Peyton, Philip J
2016-06-01
Many areas of medicine have shown bias towards the publication of studies with positive results. To estimate publication bias in the anesthesia literature, we reviewed all abstracts presented at the American Society of Anesthesiologists (ASA) annual meetings over a four-year period and compared study results (positive vs negative) with publication outcomes. This review included all abstracts from the 2001-2004 ASA annual meetings performed as randomized-controlled trials in humans. We scored their outcome results as positive or negative and assessed abstract quality using a 13-point scoring system. We then performed a systematic literature search to identify any subsequent publication of the studies and calculated the relative risk (RR) for journal publication by comparing positive vs negative studies. Of 5,918 abstracts reviewed, 1,052 met inclusion criteria, and 564 (53.6%) of the abstracts proceeded to publication. The RR for abstracts with positive results proceeding to journal publication was 1.42 (95% confidence interval, 1.22 to 1.66; P < 0.001). This result did not change significantly after adjusting for study size and abstract quality score during logistic regression modelling. There was no significant difference in the abstract quality score between positive vs negative studies or between abstracts proceeding vs not proceeding to publication. Approximately half of the ASA annual meeting abstracts proceed to publication. After adjustment for study quality and size, abstracts with positive results were more likely to proceed to journal publication than those with negative results, suggesting publication bias in the anesthesia literature.
Ontogenetic changes in vitamin C in selected rice varieties
USDA-ARS?s Scientific Manuscript database
Vitamin C (L-ascorbic acid, AsA) is a key antioxidant for both plants and animals. In plants, AsA is involved in several key physiological processes including photosynthesis, cell expansion, cell division, growth, flowering, and senescence. In addition, AsA is an enzyme cofactor and a regulator of...
ExSPO: A Discovery Class Apodized Square Aperture (ASA) Expo-Planet Imaging Space Telescope Concept
NASA Technical Reports Server (NTRS)
Gezari, D.; Harwit, M.; Lyon, R.; Melnick, G.; Papaliolos, G.; Ridgeway, S.; Woodruff, R.; Nisenson, P.; Oegerle, William (Technical Monitor)
2002-01-01
ExSPO is a Discovery Class (approx. 4 meter) apodized square aperture (ASA) space telescope mission designed for direct imaging of extrasolar Earth-like planets, as a precursor to TPF. The ASA telescope concept, instrument design, capabilities, mission plan and science goals are described.
BOREAS RSS-2 Extracted Reflectance Factors Derived from ASAS Imagery
NASA Technical Reports Server (NTRS)
Russell, C.; Hall, Forrest G. (Editor); Nickerson, Jaime (Editor); Dabney, P.; Kovalick, W.; Graham, D.; Bur, Michael; Irons, James R.; Tierney, M.
2000-01-01
The BOREAS RSS-2 team derived atmospherically corrected bidirectional reflectance factor means from multispectral, multiangle ASAS imagery for small homogeneous areas near several BOREAS sites. The ASAS imagery was acquired from the C-130 aircraft platform in 1994 and 1996. The data are stored in tabular ASCII files.
[Acetylsalicylic acid desensitization in the new era of percutaneous coronary intervention].
Fuertes Ferre, Georgina; Ferrer Gracia, Maria Cruz; Calvo Cebollero, Isabel
2015-09-21
Dual antiplatelet therapy is essential in patients undergoing percutaneous coronary intervention with stent implantation. Hypersensitivity to acetylsalicylic acid (ASA) limits treatment options. Desensitization to ASA has classically been studied in patients with respiratory tract disease. Over the last years, many protocols have been described about ASA desensitization in patients with ischemic heart disease, including acute coronary syndrome and the need for coronary stent implantation. It is important to know the efficacy and safety of ASA desensitization in these patients. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.
Double-blind comparative trial of indoprofen and acetylsalicylic acid in osteoarthritis.
Katona, G
1981-01-01
The effectiveness, safety and acceptability of indoprofen (IP) and acetylsalicylic acid (ASA) were assessed in patients with osteoarthritis, in a double-blind comparative trial. Each patient received IP 600 mg/day or ASA 2100 mg/day for a four-week period; after a one-week wash-out period, the same drug was given at a higher dosage (IP 800 or ASA 2800 mg/day) for another four weeks. Seventeen patients on indoprofen and 14 on SAS completed the trial. A significant improvement was obtained with indoprofen in the different parameters measuring pain, from the first treatment period; results were similar at the end of the second period. Results with ASA, at both dosages, appeared less impressive. Two patients on indoprofen and five on ASA complained of side effects.
Kung, Shiang-Ju; Choudhary, Cuckoo; McGeady, Stephen J; Cohn, John R
2006-09-01
5-Aminosalicylic acid (5-ASA)-containing drugs are the mainstay of therapy in inflammatory bowel disease, but adverse reactions to these medications are relatively common. Because there may be a lack of cross-reactivity among the various 5-ASA formulations, treatment with alternative preparations is sometimes possible even after an apparent allergic reaction to a 5-ASA product. To describe a patient with a possible allergy to 2 different 5-ASA drugs who tolerated a third. A 27-year-old man with Crohn disease developed a rash while taking mesalamine (Pentasa and Asacol). Treatment with 5-ASA products was discontinued, and 6-mercaptopurine and prednisone were prescribed. He then experienced multiorgan failure secondary to herpes simplex infection, which required discontinuation of the immunosuppressive therapy. After recovery from the acute infection, he underwent successful graded challenge with balsalazide. The patient continued treatment with balsalazide for 9 months, with good control of his inflammatory bowel disease and no adverse effects. Adverse reactions to 1 or more 5-ASA medications do not necessarily preclude the use of others in the same class. A treatment algorithm for patients with adverse reactions to 5-ASA is outlined based on the case report and review of the literature.
Ettienne-Gittens, Reynolette; Boushey, Carol J.; Au, Donna; Murphy, Suzanne P.; Lim, Unhee; Wilkens, Lynne
2016-01-01
The ASA24 is a web application which enables the collection of self-administered dietary recalls thus utilizing technology to overcome some of the limitations of traditional assessment methodologies. Older adults, particularly those from certain ethnic groups may have less access to and may be less receptive to technology. This research sought to determine the level of access to the internet as well as evaluate the feasibility of using a web-based alternative dietary data collection method in older, multiethnic adults. Participants completed three telephone administered diet recalls (n=347), and were asked to complete a one day recall via the ASA24. They were also asked to evaluate their experience with using the ASA24 system. Almost 60% of the participants reported no access to a computer or internet access, with African Americans and Latinos less likely than non-Hispanic Whites and Japanese-Americans to have access. Of those with access to the internet (n=100), 44% of the participants accessed the ASA24 system and 37% successfully launched the ASA24 program. However, most respondents preferred the traditional diet recall methodology over the ASA24. Further research is needed to investigate recruitment and use of electronic data collection methodologies in older adults. PMID:28149712
Trofa, David; Agovino, Mariangela; Stehr, Frank; Schäfer, Wilhelm; Rykunov, Dmitry; Fiser, András; Hamari, Zsuzsanna; Nosanchuk, Joshua D.; Gácser, Attila
2009-01-01
A reconstituted human tissue model was used to mimic Candida albicans and Candida parapsilosis infection in order to investigate the protective effects of acetylsalicylic acid (aspirin, ASA). We found that therapeutic concentrations of ASA reduced tissue damage in the in vitro infection model. We further evaluated the lipase inhibitory effects of ASA by investigating the growth of C. albicans, C. parapsilosis and C. parapsilosis lipase negative (Δcplip1-2/Δcplip1-2) mutants in a lipid rich minimal medium supplemented with olive oil and found that a therapeutic concentration of ASA inhibited the growth of wild type fungi. The lipase inhibitors quinine and ebelactone B were also shown to reduce growth and protect against tissue damage from Candida species, respectively. A lipolytic activity assay also showed that therapeutic concentrations of ASA inhibited C. antarctica and C. cylindracea purified lipases obtained through a commercial kit. The relationship between ASA and lipase was characterized through a computed structural model of the Lipase-2 protein from C. parapsilosis in complex with ASA. The results suggest that development of inhibitors of fungal lipases could result in broad-spectrum therapeutics, especially since fungal lipases are not homologous to their human analogues. PMID:19703582
Schachtel, Bernard P; Voelker, Michael; Sanner, Kathleen M; Gagney, Diana; Bey, Mary; Schachtel, Emily J; Becka, Michael
2010-12-01
To determine acute analgesia by acetylsalicylic acid (ASA) when combined with pseudoephedrine (PSE) in patients with upper respiratory tract infection (URTI), we used the sore throat pain model to measure single-dose effects of ASA 500 mg/PSE 30 mg, ASA 1000 mg/PSE 60 mg, and acetaminophen (APAP) 1000 mg/PSE 60 mg (serving as a positive control). Under double-blind, randomized, placebo-controlled conditions, 640 adult patients with confirmed acute pharyngitis and rhinosinusitis associated with URTI rated throat pain intensity and relief at intervals over 6 hours. Efficacy was demonstrated for both doses of ASA/PSE compared with placebo for all end points, including total pain relief and summed pain intensity differences, beginning at 20 minutes on both scales (all P < .05), and the efficacy of APAP/PSE compared with placebo was confirmed (P < .01). Greater differences in pain relief and intensity were also demonstrated between the higher and lower doses of ASA/PSE (P < .05), in particular, among 329 patients with severe pain, as well as between ASA 1000 mg/PSE 60 mg and APAP 1000 mg/PSE 60 mg (P < .05). No serious adverse events were reported. This study demonstrates that ASA is a well-tolerated and effective analgesic in 500- and 1000-mg doses when combined with pseudoephedrine.
Enzymatic Production of Ascorbic Acid-2-phosphate by Recombinant Acid Phosphatase.
Zheng, Kai; Song, Wei; Sun, Anran; Chen, Xiulai; Liu, Jia; Luo, Qiuling; Wu, Jing
2017-05-24
In this study, an environmentally friendly and efficient enzymatic method for the synthesis of l-ascorbic acid-2-phosphate (AsA-2P) from l-ascorbic acid (AsA) was developed. The Pseudomonas aeruginosa acid phosphatase (PaAPase) was expressed in Escherichia coli BL21. The optimal temperature, optimal pH, K m , k cat , and catalytic efficiency of recombinant PaAPase were 50 °C, 5.0, 93 mM, 4.2 s -1 , and 2.7 mM -1 min -1 , respectively. The maximal dry cell weight and PaAPase phosphorylating activity reached 8.5 g/L and 1127.7 U/L, respectively. The highest AsA-2P concentration (50.0 g/L) and the maximal conversion (39.2%) were obtained by incubating 75 g/L intact cells with 88 g/L AsA and 160 g/L sodium pyrophosphate under optimal conditions (0.1 mM Ca 2+ , pH 4.0, 30 °C) for 10 h; the average AsA-2P production rate was 5.0 g/L/h, and the AsA-2P production system was successfully scaled up to a 7.5 L fermenter. Therefore, the enzymatic process showed great potential for production of AsA-2P in industry.
Whitmore, Robert G; Stephen, James H; Vernick, Coleen; Campbell, Peter G; Yadla, Sanjay; Ghobrial, George M; Maltenfort, Mitchell G; Ratliff, John K
2014-01-01
The Charlson Comorbidity Index (CCI) and the American Society of Anesthesiologists (ASA) Physical Status Classification System (ASA grade) are useful for predicting morbidity and mortality for a variety of disease processes. To evaluate CCI and ASA grade as predictors of complications after spinal surgery and examine the correlation between these comorbidity indices and the cost of care. Prospective observational study. All patients undergoing any spine surgery at a single academic tertiary center over a 6-month period. Direct health-care costs estimated from diagnosis related group and Current Procedural Terminology (CPT) codes. Demographic data, including all patient comorbidities, procedural data, and all complications, occurring within 30 days of the index procedure were prospectively recorded. Charlson Comorbidity Index was calculated from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes and ASA grades determined from the operative record. Diagnosis related group and CPT codes were captured for each patient. Direct costs were estimated from a societal perspective using Medicare rates of reimbursement. A multivariable analysis was performed to assess the association of the CCI and ASA grade to the rate of complication and direct health-care costs. Two hundred twenty-six cases were analyzed. The average CCI score for the patient cohort was 0.92, and the average ASA grade was 2.65. The CCI and ASA grade were significantly correlated, with Spearman ρ of 0.458 (p<.001). Both CCI and ASA grade were associated with increasing body mass index (p<.01) and increasing patient age (p<.0001). Increasing CCI was associated with an increasing likelihood of occurrence of any complication (p=.0093) and of minor complications (p=.0032). Increasing ASA grade was significantly associated with an increasing likelihood of occurrence of a major complication (p=.0035). Increasing ASA grade showed a significant association with increasing direct costs (p=.0062). American Society of Anesthesiologists and CCI scores are useful comorbidity indices for the spine patient population, although neither was completely predictive of complication occurrence. A spine-specific comorbidity index, based on ICD-9-CM coding that could be easily captured from patient records, and which is predictive of patient likelihood of complications and mortality, would be beneficial in patient counseling and choice of operative intervention. Copyright © 2014 Elsevier Inc. All rights reserved.
Nitric oxide-releasing aspirin but not conventional aspirin improves healing of experimental colitis
Zwolinska-Wcislo, Malgorzata; Brzozowski, Tomasz; Ptak-Belowska, Agata; Targosz, Aneta; Urbanczyk, Katarzyna; Kwiecien, Slawomir; Sliwowski, Zbigniew
2011-01-01
AIM: To determine the effect of non-selective cyclooxygenase (COX) inhibitors, selective COX-2 inhibitors and nitric oxide (NO)-releasing aspirin in the healing of ulcerative colitis. METHODS: Rats with 2,4,6 trinitrobenzenesulfon-ic acid (TNBS)-induced colitis received intragastric (ig) treatment with vehicle, aspirin (ASA) (a non-selective COX inhibitor), celecoxib (a selective COX-2 inhibitor) or NO-releasing ASA for a period of ten days. The area of colonic lesions, colonic blood flow (CBF), myeloperoxidase (MPO) activity and expression of proinflammatory markers COX-2, inducible form of nitric oxide synthase (iNOS), IL-1β and tumor necrosis factor (TNF)-α were assessed. The effects of glyceryl trinitrate (GTN), a NO donor, and 2-(4-carboxyphenyl)-4,5-dihydro-4,4,5,5-tetramethyl-1H-imidazolyl-1-oxy-3-oxide, onopotassium salt (carboxy-PTIO), a NO scavenger, administered without and with ASA or NO-ASA, and the involvement of capsaicin-sensitive afferent nerves in the mechanism of healing the experimental colitis was also determined. RESULTS: Rats with colitis developed macroscopic and microscopic colonic lesions accompanied by a significant decrease in the CBF, a significant rise in colonic weight, MPO activity and plasma IL-1β and TNF-α levels. These effects were aggravated by ASA and 5-(4-chlorophenyl)-1-(4-methoxyphenyl)-3-(trifluoromethyl)-1H-pyrazole (SC-560), but not celecoxib and counteracted by concurrent treatment with a synthetic prostaglandin E2 (PGE2) analog. Treatment with NO-ASA dose-dependently accelerated colonic healing followed by a rise in plasma NOx content and CBF, suppression of MPO and downregulation of COX-2, iNOS, IL-1β and TNF-α mRNAs. Treatment with GTN, the NO donor, significantly inhibited the ASA-induced colonic lesions and increased CBF, while carboxy-PTIO or capsaicin-denervation counteracted the NO-ASA-induced improvement of colonic healing and the accompanying increase in the CBF. These effects were restored by co-treatment with calcitonin gene related peptide (CGRP) and NO-ASA in capsaicin-denervated animals. CONCLUSION: NO-releasing ASA, in contrast to ASA, COX-1 inhibitors, and SC-560, accelerated the healing of colitis via a mechanism involving NO mediated improvement of microcirculation and activation of sensory nerves releasing CGRP. PMID:22039321
NASA Technical Reports Server (NTRS)
Smith, Jeremy C.; Bussink, Frank J. L.
2008-01-01
This paper presents the results from a study that investigates the performance of a tactical Airborne Separation Assistance System (ASAS) in en route airspace, under varying demand levels, with realistic traffic flows. The ASAS concept studied here allows flight crews of equipped aircraft to perform separation from other air traffic autonomously. This study addresses the tactical aspects of an ASAS using aircraft state data (i.e. position and velocity) to detect and resolve projected conflicts. In addition, use of a conflict prevention system helps ASAS-equipped aircraft avoid maneuvers that may cause new conflicts. ASAS-capable aircraft are equipped with satellite-based navigation and Automatic Dependent Surveillance Broadcast (ADS-B) for transmission and receipt of aircraft state data. In addition to tactical conflict detection and resolution (CD&R), a complete, integrated ASAS is likely to incorporate a strategic CD&R component with a longer look-ahead time, using trajectory intent information. A system-wide traffic flow management (TFM) component, located at the FAA command center helps aircraft to avoid regions of excessive traffic density and complexity. A Traffic Alert and Collision Avoidance System (TCAS), as used today is the system of last resort. This integrated approach avoids sole reliance on the use of the tactical CD&R studied here, but the tactical component remains a critical element of the complete ASAS. The focus of this paper is to determine to what extent the proposed tactical component of ASAS alone can maintain aircraft separation at demand levels up to three times that of current traffic. The study also investigates the effect of mixing ASAS-equipped aircraft with unequipped aircraft (i.e. current day) that do not have the capability to self-separate. Position and velocity data for unequipped aircraft needs to be available to ASASequipped. Most likely, for this future concept, state data would be available from instrument flight rules (IFR) aircraft, equipped with at least ADS-B transmission capability. The objective is to reduce the number of losses of separation to a minimum and investigate the limits of tactical-only CD&R. Thus, the objective is not, expressly, to achieve zero losses of separation with tactical ASAS because this is one component of an integrated ASAS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Xianwei, E-mail: XWang2@UAMS.edu; Lu, Jingjun; Khaidakov, Magomed
Aspirin (acetyl salicylic acid, ASA) is a common drug used for its analgesic and antipyretic effects. Recent studies show that ASA not only blocks cyclooxygenase, but also inhibits NADPH oxidase and resultant reactive oxygen species (ROS) generation, a pathway that underlies pathogenesis of several ailments, including hypertension and tissue remodeling after injury. In these disease states, angiotensin II (Ang II) activates NADPH oxidase via its type 1 receptor (AT1R) and leads to fibroblast growth and collagen synthesis. In this study, we examined if ASA would inhibit NADPH oxidase activation, upregulation of AT1R transcription, and subsequent collagen generation in mouse cardiacmore » fibroblasts challenged with Ang II. Mouse heart fibroblasts were isolated and treated with Ang II with or without ASA. As expected, Ang II induced AT1R expression, and stimulated cardiac fibroblast growth and collagen synthesis. The AT1R blocker losartan attenuated these effects of Ang II. Similarly to losartan, ASA, and its SA moiety suppressed Ang II-mediated AT1R transcription and fibroblast proliferation as well as expression of collagens and MMPs. ASA also suppressed the expression of NADPH oxidase subunits (p22{sup phox}, p47{sup phox}, p67{sup phox}, NOX2 and NOX4) and ROS generation. ASA did not affect total NF-κB p65, but inhibited its phosphorylation and activation. These observations suggest that ASA inhibits Ang II-induced NADPH oxidase expression, NF-κB activation and AT1R transcription in cardiac fibroblasts, and fibroblast proliferation and collagen expression. The critical role of NADPH oxidase activity in stimulation of AT1R transcription became apparent in experiments where ASA also inhibited AT1R transcription in cardiac fibroblasts challenged with H{sub 2}O{sub 2}. Since SA had similar effect as ASA on AT1R expression, we suggest that ASA's effect is mediated by its SA moiety. -- Highlights: ► Aspirin in therapeutic concentrations decreases mouse cardiac fibroblast growth and collagen formation. ► Aspirin decreases the transcription of angiotensin II type 1 receptor by inhibiting NADPH oxidase–NF-κB pathway. ► The inhibition of angiotensin II type 1 receptor expression may be the basis for reduction in fibroblast growth and collagen formation. ► The effects of aspirin appear to be mediated via its salicylate moiety.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grach, V. S., E-mail: vsgrach@app.sci-nnov.ru; Garasev, M. A.
2015-07-15
We consider the interaction of a isolated conducting sphere with a collisional weakly ionized plasma in an external field. We assume that the plasma consists of two species of ions neglecting of electrons. We take into account charging of the sphere due to sedimentation of plasma ions on it, the field of the sphere charge and the space charge, as well as recombination and molecular diffusion. The nonstationary problem of interaction of the sphere with the surrounding plasma is solved numerically. The temporal dynamics of the sphere charge and plasma perturbations is analyzed, as well as the properties of themore » stationary state. It is shown that the duration of transient period is determined by the recombination time and by the reverse conductivity of ions. The temporal dynamics of the sphere charge and plasma perturbations is determined by the intensity of recombination processes relative to the influence of the space charge field and diffusion. The stationary absolute value of the sphere charge increases linearly with the external electric field, decreases with the relative intensity of recombination processes and increases in the presence of substantial diffusion. The scales of the perturbed region in the plasma are determined by the radius of the sphere, the external field, the effect of diffusion, and the relative intensity of recombination processes. In the limiting case of the absence of molecular diffusion and a strong external field, the properties of the stationary state coincide with those obtained earlier as a result of approximate solution.« less
Explorations in fuzzy physics and non-commutative geometry
NASA Astrophysics Data System (ADS)
Kurkcuoglu, Seckin
Fuzzy spaces arise as discrete approximations to continuum manifolds. They are usually obtained through quantizing coadjoint orbits of compact Lie groups and they can be described in terms of finite-dimensional matrix algebras, which for large matrix sizes approximate the algebra of functions of the limiting continuum manifold. Their ability to exactly preserve the symmetries of their parent manifolds is especially appealing for physical applications. Quantum Field Theories are built over them as finite-dimensional matrix models preserving almost all the symmetries of their respective continuum models. In this dissertation, we first focus our attention to the study of fuzzy supersymmetric spaces. In this regard, we obtain the fuzzy supersphere S2,2F through quantizing the supersphere, and demonstrate that it has exact supersymmetry. We derive a finite series formula for the *-product of functions over S2,2F and analyze the differential geometric information encoded in this formula. Subsequently, we show that quantum field theories on S2,2F are realized as finite-dimensional supermatrix models, and in particular we obtain the non-linear sigma model over the fuzzy supersphere by constructing the fuzzy supersymmetric extensions of a certain class of projectors. We show that this model too, is realized as a finite-dimensional supermatrix model with exact supersymmetry. Next, we show that fuzzy spaces have a generalized Hopf algebra structure. By focusing on the fuzzy sphere, we establish that there is a *-homomorphism from the group algebra SU(2)* of SU(2) to the fuzzy sphere. Using this and the canonical Hopf algebra structure of SU(2)* we show that both the fuzzy sphere and their direct sum are Hopf algebras. Using these results, we discuss processes in which a fuzzy sphere with angular momenta J splits into fuzzy spheres with angular momenta K and L. Finally, we study the formulation of Chern-Simons (CS) theory on an infinite strip of the non-commutative plane. We develop a finite-dimensional matrix model, whose large size limit approximates the CS theory on the infinite strip, and show that there are edge observables in this model obeying a finite-dimensional Lie algebra, that resembles the Kac-Moody algebra.
Directional spectral emissivity measurement system
NASA Technical Reports Server (NTRS)
Halyo, Nesim (Inventor); Pandey, Dhirendra K. (Inventor)
1992-01-01
Apparatus and process for determining the emissivity of a test specimen including an integrated sphere having two concentric walls with a coolant circulating therebetween, and disposed within a chamber which may be under ambient, vacuum or inert gas conditions. A reference sample is disposed within the sphere with a monochromatic light source in optical alignment therewith. A pyrometer is in optical alignment with the test sample for obtaining continuous test sample temperature measurements during a test. An arcuate slit port is provided through the spaced concentric walls of the integrating sphere with a movable monochromatic light source extending through and movable along the arcuate slit port. A detector system extends through the integrating sphere for continuously detecting an integrated signal indicative of all radiation within its field of view, as a function of the emissivity of the test specimen at various temperatures and various angle position of the monochromatic light source. A furnace for heating the test sample to approximately 3000 K. and control mechanism for transferring the heated sample from the furnace to the test sample port in the integrating sphere is also contained within the chamber.
Ihejirika, Rivka C; Thakore, Rachel V; Sathiyakumar, Vasanth; Ehrenfeld, Jesse M; Obremskey, William T; Sethi, Manish K
2015-04-01
Although recent literature has demonstrated the utility of the ASA score in predicting postoperative length of stay, complication risk and potential utilization of other hospital resources, the ASA score has been inconsistently assigned by anaesthesia providers. This study tested the reliability of assignment of the ASA score classification by both attending anaesthesiologists and anaesthesia residents specifically among the orthopaedic trauma patient population. Nine case-based scenarios were created involving preoperative patients with isolated operative orthopaedic trauma injuries. The cases were created and assigned a reference score by both an attending anaesthesiologist and orthopaedic trauma surgeon. Attending and resident anaesthesiologists were asked to assign an ASA score for each case. Rater versus reference and inter-rater agreement amongst respondents was then analyzed utilizing Fleiss's Kappa and weighted and unweighted Cohen's Kappa. Thirty three individuals provided ASA scores for each of the scenarios. The average rater versus reference reliability was substantial (Kw=0.78, SD=0.131, 95% CI=0.73-0.83). The average rater versus reference Kuw was also substantial (Kuw=0.64, SD=0.21, 95% CI=0.56-0.71). The inter-rater reliability as evaluated by Fleiss's Kappa was moderate (K=0.51, p<.001). An inter-rater comparison within the group of attendings (K=0.50, p<.001) and within the group of residents were both moderate (K=0.55, p<.001). There was a significant increase in the level of inter-rater reliability from the self-reported 'very uncomfortable' participants to the 'very comfortable' participants (uncomfortable K=0.43, comfortable K=0.59, p<.001). This study shows substantial agreement strength for reliability of the ASA score among anaesthesiologists when evaluating orthopaedic trauma patients. The significant increase in inter-rater reliability based on anaesthesiologists' comfort with the ASA scoring method implies a need for further evaluation of ASA assessment training and routine use on the ground. These findings support the use of the ASA score as a statistically reliable tool in orthopaedic trauma. Copyright © 2014 Elsevier Ltd. All rights reserved.
Yasin, Anas Lotfi; Yasin, Ahmad Lotfi; Basha, Walid Salim
2016-03-01
Anti sperm antibodies (ASA) can present in serum and semen and they may lead to impair the sperms function leading to infertility. The precise mechanism of generation of these antibodies is yet to be discovered. This study was performed to determine the prevalence of anti-sperm antibodies (ASA) in patients with unexplained infertility. The study was initiated also to explore the possible factors that may associate with ASA formation and how ASA status is associated with pregnancy rates after going with in vitro fertilization - intracytoplasmic sperm injection (IVF-ICSI). A cross-sectional study was conducted on 42 normal infertile couples consulting Razan Medical Center for Infertility & I.V.F. in Nablus, Palestine, from December 2012 - March 2013. Serum levels of immunoglobulins G (IgG) ASA were measured in participants (males and females) using enzyme-linked immunosorbent assay (ELISA). In addition, participants also filled a questionnaire about the presence of previous varicocele repair, inguinal hernia repair, orchitis, testicular trauma and vasectomy reversal among males and severe coitus bleeding and coitus during menses or puerperium among females. Couples were also asked about previous IVF-ICSI procedures and the outcome of the procedure in terms of either they got pregnant or not. Data was analysed using SPSS software. The prevalence of ASA was 14.3% (6/42) among all couples, 9.5% (4/42) among males and 4.8% (2/42) among females. There was no significant relationship between previous varicocele repair, previous inguinal hernia repair, or orchitis and formation of ASA (p value =0.64, 0.56, and 0.26 respectively). Previous trauma, vasovasostomy, severe coitus bleeding and coitus during menses or puerperium were not observed in any of the study sample. ASA did not seem to affect the outcome of IVF-ICSI (p-value =0.54). Prevalence of ASA in infertile couples in the north part of Palestine is similar to that obtained worldwide. ASA formation does not relate to any of the studied risk factors and does not seem to associate with pregnancy rate after IVF-ICSI. We recommend further studies using a larger sample size and including all parts of Palestine in order to generalize the obtained results.
Otto, Gordon Philipp; Sossdorf, Maik; Boettel, Janina; Kabisch, Björn; Breuel, Hannes; Winning, Johannes; Lösche, Wolfgang
2013-01-01
Sepsis and its sequelae of multiple organ failure is one of the leading causes of death in the industrial countries. Several studies have shown that patients who are treated with low-dose acetyl salicylic acid (ASA) for secondary prevention of atherothrombosis may have a lower risk to develop organ failure in the case of critical illness. The benefit of ASA is probably due to an inhibition of platelet activation as well as an increase in the formation of anti-inflammatory lipoxin A4. On the other hand, the effect of ASA could be - at least partially - an indirect one, caused by atherosclerotic vascular diseases as the cause of ASA treatment. Atherosclerosis is considered as a moderate systemic inflammation and we hypothesise that this chronic condition could have an impact on the outcome in sepsis. To get more information on the benefit of ASA in critically ill patients and on possible interference with atherosclerotic vascular diseases, we analysed the medical records of 886 septic patients who were admitted to the surgical intensive care unit (ICU) of a university hospital. Logistic regression analysis indicated that patients who were treated during the ICU stay with ASA (100 mg/d) had a significantly lower mortality. Odds ratios (ORs; with 95% confidential intervals) of 0.56 (0.37-0.84) and 0.57 (0.39-0.83) were calculated for ICU and hospital mortality, respectively. In contrast, statin treatment did not have significant effect on mortality. Diagnosis of atherosclerotic vascular diseases according to ICD classification did not influence ICU mortality but lowered hospital mortality (OR = 0.71 (0.52-0.99)). Subgroup analysis provided preliminary evidence that clopidogrel when given as only anti-platelet drug may have a similar benefit as ASA, but the combination of ASA and clopidogrel failed to improve the outcome. The time course of plasma fibrinogen and procalcitonin levels indicate that ASA seems to reduce the activation of haemostasis and increase the resolution of inflammation. It is concluded that prospective interventional studies should be done to test the use of ASA as novel therapeutic approach in critically ill patients.
Multiregion bicentric-spheres models of the head for the simulation of bioelectric phenomena.
Vatta, Federica; Bruno, Paolo; Inchingolo, Paolo
2005-03-01
Equations are derived for the electric potentials [electroencephalogram (EEG)] produced by dipolar sources in a multiregion bicentric-spheres volume-conductor head model. Being the equations valid for an arbitrary number of regions, our proposal is a generalization of many spherical models presented so far in literature, each of those regarded as a particular case of our multiregion model. Moreover, our approach allows considering new features of the head volume-conductor to better approximate electrical properties of the real head.
Acetylsalicylic acid (aspirin) test for the diagnosis of renovascular hypertension.
Gluszek, J; Posadzy-Malaczynska, A; Tykarski, A; Pupek-Musialik, D; Gracz, M; Kara-Perz, H
1997-06-01
To determine whether the administration of acetylsalicylic acid (ASA, also known as Aspirin) differentiates patients with renovascular hypertension from those with essential hypertension, in order to provide a simple alternative to more expensive forms of diagnosis for this condition. Trial of ASA test in patients with previously diagnosed essential and renovascular hypertension. Inpatient department of an academic health sciences centre in Poznan, Poland. Forty patients with essential hypertension and 21 patients with renovascular hypertension. Patients were given an intravenous injection of ASA (10 mg/kg body weight), blood pressure was measured and blood was sampled and assayed for plasma renin activity (PRA) before and 30 minutes after the injection. ASA infusion in patients with renovascular hypertension resulted in a decrease in PRA from 15.2 (standard deviation [SD] 12.4) ng/mL per hour to 7.2 (SD 9.8) ng/mL per hour, whereas in patients with essential hypertension the initial PRA was significantly lower before ASA administration and did not change afterward. In patients with renovascular hypertension, the mean systolic, diastolic and arterial pressure decreased significantly (p < 0.001) after ASA infusion, but these did not change in patients with essential hypertension. Based on the criterion of 4 mm Hg as a detectable decrease in mean blood pressure, the sensitivity of the ASA test was 95.0% and the specificity 82.5%; its positive predictive value was 74% and its negative predictive value 97%. The precise measurement of blood pressure during the ASA test may provide a useful method of differentiating between patients with renovascular and essential hypertension.
Akram, Nudrat A.; Shafiq, Fahad; Ashraf, Muhammad
2017-01-01
Over-production of reactive oxygen species (ROS) in plants under stress conditions is a common phenomenon. Plants tend to counter this problem through their ability to synthesize ROS neutralizing substances including non-enzymatic and enzymatic antioxidants. In this context, ascorbic acid (AsA) is one of the universal non-enzymatic antioxidants having substantial potential of not only scavenging ROS, but also modulating a number of fundamental functions in plants both under stress and non-stress conditions. In the present review, the role of AsA, its biosynthesis, and cross-talk with different hormones have been discussed comprehensively. Furthermore, the possible involvement of AsA-hormone crosstalk in the regulation of several key physiological and biochemical processes like seed germination, photosynthesis, floral induction, fruit expansion, ROS regulation and senescence has also been described. A simplified and schematic AsA biosynthetic pathway has been drawn, which reflects key intermediates involved therein. This could pave the way for future research to elucidate the modulation of plant AsA biosynthesis and subsequent responses to environmental stresses. Apart from discussing the role of different ascorbate peroxidase isoforms, the comparative role of two key enzymes, ascorbate peroxidase (APX) and ascorbate oxidase (AO) involved in AsA metabolism in plant cell apoplast is also discussed particularly focusing on oxidative stress perception and amplification. Limited progress has been made so far in terms of developing transgenics which could over-produce AsA. The prospects of generation of transgenics overexpressing AsA related genes and exogenous application of AsA have been discussed at length in the review. PMID:28491070
Dissolution of Commercially Available Mesalamine Formulations at Various pH Levels.
Tenjarla, Srini
2015-06-01
Mesalamine (5-aminosalicylic acid; 5-ASA) is recommended first-line therapy for mild-to-moderate ulcerative colitis. Many mesalamine formulations employ a pH-dependent release mechanism designed to maximize drug release in the colon. This study compared the in vitro release of 5-ASA from six commercially available mesalamine formulations at pH levels similar to those typically encountered in the human gastrointestinal tract. The release of 5-ASA from six mesalamine formulations [Mesalazin-Kohlpharma (Kohlpharma, Germany), Mesalazin-Eurim (Eurimpharm, Germany), Mesalazina-Faes (Faes Farma, Spain), Mesalazine EC (Actavis B.V., Netherlands), Mesalazine EC 500 PCH (Pharmachemie B.V., Netherlands); multimatrix mesalamine (Shire US Inc., USA)] was monitored separately at three different pH levels [1.0 (2 h), 6.4 (1 h), and 7.2 (8 h)] using United States Pharmacopeia dissolution apparatus II. The dissolution percentage was calculated as a mean of 12 units for each formulation. At pH 1.0 and 6.4, <1 % of 5-ASA release was observed for each of the mesalamine formulations tested. At pH 7.2, complete release of 5-ASA occurred within 1 h for Mesalazine EC and Mesalazine EC 500 PCH, and within 2 h for Mesalazin-Kohlpharma, Mesalazin-Eurim, and Mesalazina-Faes; complete release of 5-ASA from multimatrix mesalamine occurred within 7 h. Little variability in rate of 5-ASA dissolution was observed between tablets of each formulation. At pH 7.2, 5-ASA release profiles were variable among the commercially available mesalamine formulations that were tested.
ERIC Educational Resources Information Center
Rossman, Allan; Dietz, E. Jacquelin; Moor, David
2013-01-01
David Moore is Professor Emeritus of Statistics at Purdue University. He served as the first President of the International Association for Statistical Education (IASE) from 1993-1995 and as President of the American Statistical Association (ASA) in 1998. He is a Fellow of the ASA and of the IMS and was awarded the ASA's Founders Award in…
Pulsating Stars in the ASAS-3 Database. I. beta Cephei Stars
NASA Astrophysics Data System (ADS)
Pigulski, A.
2005-06-01
We present results of an analysis of the ASAS-3 data for short-period variables from the recently published catalog of over 38000 stars. Using the data available in the literature we verify the results of the automatic classification related to \\beta Cep pulsators. In particular, we find that 14 stars in the catalog can be classified unambiguously as new beta Cep stars. By means of periodogram analysis we derive the frequencies and amplitudes of the excited modes. The main modes in the new beta Cep stars have large semi-amplitudes, between 35 and 80 mmag. Up to four modes were found in some stars. Two (maybe three) new beta Cep stars are members of southern young open clusters: ASAS 164409-4719.1 belongs to NGC 6200, ASAS 164630-4701.2 is a member of Hogg 22, and ASAS 164939-4431.7 could be a member of NGC 6216. We also analyze the photometry of four known beta Cep stars in the ASAS-3 catalog, namely IL Vel, NSV 24078, V1449 Aql and SY Equ. Finally, we discuss the distribution of beta Cep stars in the Galaxy.
Veterinary Forensic Pathology of Animal Sexual Abuse.
Stern, A W; Smith-Blackmore, M
2016-09-01
Animal sexual abuse (ASA) involves harm inflicted on animals for the purposes of human sexual gratification and includes such terms as bestiality, zoophilia, zoosadism, animal sexual assault, and others. The prevalence of ASA is not known, although it may be more common than is currently perceived. Veterinarians have the skills required to identify and document cases of ASA. This article reviews the terminology, legal definitions and forms of ASA, and its social and psychological context. An investigative approach is outlined, including an alternate light source examination; collection of swabs for DNA analysis; sampling vaginal washes, rectal washes, and toenails for trace evidence and biologic analyses; radiographic studies; and a complete forensic necropsy, including histopathology. Gross lesions identified in ASA victims include injuries to the anus, rectum, penis, scrotum, nipples, and vagina; the presence of foreign bodies; and abrasions, bruising, and other evidence of nonaccidental injury. Specialized procedures, including examination using alternate light sources and screening tests to identify human seminal fluid within samples from ASA victims, are of potential value but have not been validated for use in animals. © The Author(s) 2016.
McMillan, Matthew; Brearley, Jacqueline
2013-05-01
To evaluate the interobserver variability in the assignment of the American Society of Anesthesiologists Physical Status Classification (ASA-PSC) to compromised small animal patients amongst a group of veterinary anaesthetists. Anonymous internet survey. Hypothetical case presentations. Sixteen hypothetical small animal cases with differing degrees of physiological or patho-physiological compromise were presented as part of an internet survey. Respondents were asked to assign a single ASA-PSC to each case and also to answer a number of demographic questions. ASA-PSC scores were considered separately and then grouped as scores of I-II and III-V. Agreement was analysed using the modified kappa statistic for multiple observers. Data were then sorted into various demographic groups for further analysis. There were 144 respondents of which 60 (~42%) were anaesthesia diplomates, 24 (~17%) were post-residency (nondiploma holders), 24 (~17%) were current anaesthesia residents, 21 (~15%) were general practitioners, 12 (~8%) were veterinary nurses or technicians, and 3 (~2%) were interns. Although there was a majority agreement (>50% in a single category) in 15 of the 16 cases, ASA-PSC were spread over at least three ASA-PS classifications for every case. Overall agreement was considered only fair (κ = 0.24, mean ± SD agreement 46 ± 7%). When comparing grouped data (ASA-PSC I-II versus III-V) overall agreement remained fair (κ = 0.36, mean ± SD agreement 69 ± 19%). There was no difference in ASA-PSC assignment between any of the demographic groups investigated. This study suggests major discrepancies can occur between observers given identical information when using the ASA-PSC to categorise health status in compromised small animal patients. The significant potential for interobserver variability in classification allocation should be borne in mind when the ASA-PSC is used for clinical, scientific and statistical purposes. © 2013 The Authors. Veterinary Anaesthesia and Analgesia © 2013 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.
The Animal Sciences Academic Quadrathlon: history, current status, and recommendations.
Kauffman, R G; Jobsis, C T; Onan, G; Day, B N
2011-07-01
The Animal Sciences Academic Quadrathlon (AQ) provides opportunities for teams of undergraduate animal and dairy science students to participate in regional American Society of Animal Science (ASAS)/American Dairy Science Association (ADSA) meetings and to collectively exhibit their knowledge and talents competitively in 4 categories: 1) solving practical, hands-on, laboratory-type problems; 2) providing written answers to essay-type questions about principles and concepts; 3) preparing and communicating orally and extemporaneously topics of current animal science interest; and 4) quickly responding to short-answer questions provided in the form of double-elimination quiz bowls. Each team is selected by winning the local AQ at their university. Overall and individual category winning teams are recognized, but team rankings are not emphasized. The ASAS/ADSA members provide leadership for organizing and conducting the AQ, and ASAS and each university provide travel expenses for students. The ultimate purpose is to stimulate academic excellence among undergraduate students and for the students to attend ASAS/ADSA regional scientific meetings to meet faculty and students and to attend scientific research presentations. The purpose of this document was to provide a history of the event and to make recommendations for its improvement. The AQ was conceived in 1967. During the next 10 yr, an ASAS committee developed procedures for a trial AQ held in 1980 at the ASAS Midwestern Section, Kansas State University-Manhattan, and in the next year the first official AQ was held at the ASAS Midwestern Section at the University of Nebraska-Lincoln. Starting in 1985, AQ programs were initiated at the other 3 ASAS sectional meetings, and an estimated 50,000 students representing 60 universities have participated in AQ programs since that time. If the AQ is to continue its improvement over time, it will greatly depend on sustained ASAS/ADSA faculty interest and support, as well as greater adherence to the original AQ procedures. © 2011 American Society of Animal Science. All rights reserved.
Burkholder, Greer A.; Tamhane, Ashutosh R.; Salinas, Jorge L.; Mugavero, Michael J.; Raper, James L.; Westfall, Andrew O.; Saag, Michael S.; Willig, James H.
2012-01-01
Background. Individuals infected with human immunodeficiency virus (HIV) are at increased risk for cardiovascular disease (CVD) events compared with uninfected persons. However, little is known about HIV provider practices regarding aspirin (ASA) for primary prevention of CVD. Methods. A cross-sectional study was conducted among patients attending the University of Alabama at Birmingham 1917 HIV Clinic during 2010 to determine the proportion receiving ASA for primary prevention of CVD and identify factors associated with ASA prescription. Ten-year risk for CVD events was calculated for men aged 45–79 and women aged 55–79. The 2009 US Preventive Services Task Force (USPSTF) guidelines were used to determine those qualifying for primary CVD prevention. Results. Among 397 patients who qualified to receive ASA (mean age, 52.2 years, 94% male, 36% African American), only 66 (17%) were prescribed ASA. In multivariable logistic regression analysis, diabetes mellitus (odds ratio [OR], 2.60; 95% confidence interval [CI], 1.28–5.27), hyperlipidemia (OR, 3.42; 95% CI, 1.55–7.56), and current smoking (OR, 1.87; 95% CI, 1.03–3.41) were significantly associated with ASA prescription. Odds of ASA prescription more than doubled for each additional CVD-related comorbidity present among hypertension, diabetes, hyperlipidemia, and smoking (OR, 2.13, 95% CI, 1.51–2.99). Conclusions. In this HIV-infected cohort, fewer than 1 in 5 patients in need received ASA for primary CVD prevention. Escalating likelihood of ASA prescription with increasing CVD-related comorbidity count suggests that providers may be influenced more by co-occurrence of these diagnoses than by USPSTF guidelines. In the absence of HIV-specific guidelines, interventions to improve HIV provider awareness of and adherence to existing general population guidelines on CVD risk reduction are needed. PMID:22942209
Tokuda, Yuki; Miura, Natsuko; Kobayashi, Misato; Hoshinaga, Yukiko; Murai, Atsushi; Aoyama, Hiroaki; Ito, Hiroyuki; Morita, Tatsuya; Horio, Fumihiko
2015-02-01
The aim of this study was to determine whether ascorbic acid (AsA) deficiency-induced endotoxin influx into portal blood from the gastrointestinal tract contributes to the inflammatory changes in the liver. The mechanisms by which AsA deficiency provokes inflammatory changes in the liver were investigated in Osteogenic Disorder Shionogi (ODS) rats (which are unable to synthesize AsA). Male ODS rats (6-wk-old) were fed a diet containing sufficient (300 mg/kg) AsA (control group) or a diet without AsA (AsA-deficient group) for 14 or 18 d. On day 14, the hepatic mRNA levels of acute-phase proteins and inflammation-related genes were significantly higher in the AsA-deficient group than the control group, and these elevations by AsA deficiency were exacerbated on day 18. The serum concentrations of interleukin (IL)-1β and IL-6, which induce acute-phase proteins in the liver, were also significantly elevated on day 14 in the AsA-deficient group compared with the respective values in the control group. IL-1β mRNA levels in the liver, spleen, and lung were increased by AsA deficiency. Moreover, on both days 14 and 18, the portal blood endotoxin concentration was significantly higher in the AsA-deficient group than in the control group, and a significant correlation between serum IL-1β concentrations and portal endotoxin concentrations was found in AsA-deficient rats. In the histologic analysis of the ileum tissues, the number of goblet cells per villi was increased by AsA deficiency. These results suggest that AsA deficiency-induced endotoxin influx into portal blood from the gastrointestinal tract contributes to the inflammatory changes in the liver. Copyright © 2015 Elsevier Inc. All rights reserved.
Panka, Bernardo Amisa; de Grooth, Harm-Jan; Spoelstra–de Man, Angeliquè; Looney, Mark; Tuinman, Pieter-Roel
2016-01-01
Background The acute respiratory distress syndrome (ARDS) is a life-threating disorder that contributes significantly to critical illness. No specific pharmacological interventions directed at lung injury itself, have proven effective in improving outcome of patients with ARDS. Platelet activation was identified as a key component in ARDS pathophysiology and may provide an opportunity for preventive and therapeutic strategies. We hypothesize that use of acetyl salicylic acid (ASA) may prevent and/or attenuate lung injury. Methods We conducted a systematic review of preclinical studies and meta-analysis of clinical studies investigating the efficacy of ASA in the setting of lung injury. MEDLINE, EMBASE AND COCHRANE databases were searched. Results The literature search yielded 1314 unique articles. Fifteen pre-clinical studies and eight clinical studies fulfilled the in- and exclusion criteria. In the animal studies, the overall effect of ASA was positive, e.g. ASA improved survival and attenuated inflammation and pulmonary edema. Mechanisms of actions involved, among others, are interference with the neutrophil-platelets interaction, reduction of leukotrienes, neutrophil extracellular traps and prostaglandins. High dose ASA may be the drug of choice. A meta-analysis of 3 clinical studies showed an association between ASA use and a reduced incidence of ARDS (OR 0.59, 95% CI 0.36–0.98), albeit with substantial between-study heterogeneity. All studies had their own shortcomings in methodological quality. Conclusion This systematic review of preclinical studies and meta-analysis of clinical studies suggests a beneficial role for ASA in ARDS prevention and treatment. However, the currently available data is insufficient to justify an indication for ASA in ARDS. The body of literature does support further studies in humans. We suggest clinical trials in which the mechanisms of action of ASA in lung injury models is being evaluated to guide optimal timing and dose, before prospective randomized trials. PMID:27984533
Aspirin alone and combined with a statin suppresses eicosanoid formation in human colon tissue.
Gottschall, Heike; Schmöcker, Christoph; Hartmann, Dirk; Rohwer, Nadine; Rund, Katharina; Kutzner, Laura; Nolte, Fabian; Ostermann, Annika I; Schebb, Nils Helge; Weylandt, Karsten H
2018-05-01
Eicosanoids, including prostaglandins (PGs) and thromboxanes, are broadly bioactive lipid mediators and increase colon tumorigenesis possibly through chronic inflammatory mechanisms. Epidemiological and experimental data suggest that acetylsalicylic acid (ASA) helps prevent colorectal cancer (CRC), possibly through cyclooxygenase (COX)-mediated suppression of eicosanoid, particularly PGE 2 , formation. Recent studies suggest that statins prevent CRC and improve survival after diagnosis. We identified patients on ASA and/or statin treatment undergoing routine colonoscopy and measured eicosanoid levels in colonic mucosa with targeted metabolomics technology (LC-MS/MS). ASA-treated individuals (n = 27) had significantly lower tissue eicosanoid levels of most COX-derived metabolites than untreated individuals (n = 31). In contrast, COX-derived lipid metabolites tended to be higher in patients with statin treatment (n = 7) as compared with those not receiving statins (n = 24). This effect was not discernible in subjects treated with ASA and statins (n = 11): Individuals treated with both drugs showed a pronounced suppression of COX-derived eicosanoids in colon tissue, even compared with subjects treated with ASA alone. Our data from a routine clinical setting support the hypothesis that ASA and statins could inhibit CRC development via lipid mediator modification. Further studies should directly investigate the effect of dual ASA and statin treatment on colon tumorigenesis in humans. Copyright © 2018 by the American Society for Biochemistry and Molecular Biology, Inc.
Rajeh, Nisreen A; Al-Dhaheri, Najlaa M
2017-02-01
To explore renal toxicity caused by sub-acute exposure of acrylamide and to study the protective effect of 5-Aminosalicylic acid (5-ASA) and Vitamin E (vit-E)on Acrylamide (ACR) induced renal toxicity. Methods: This study was conducted at King Fahad Medical Research Centre, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia, between August and November 2015. A total of 49 adult Wistar rats (250 ± 20g) aged 60 days were kept in a controlled environment and used in the present study. The rats were divided into 7 groups (control, ACR alone, ACR+5-ASA, ACR+vit-E, ACR+ASA+vit-E, vit-E alone, and ASA alone). After 5 days of ACR oral gavage treatment, the rats were observed for 24 hours then killed. Histopathology for the kidney and lactate dehydrogenase assay were carried out. Results: Acrylamide produced significant pathological changes in the kidney with acute tubular necrosis in the distal tubules that could be reversed by concomitant injection of rat with 5-ASA. Together with vitamin E, 5-ASA, showed maximum renal protection. No statistically significant difference was observed in either body weights or lactate dehydrogenase activity of ACR treated rats. Conclusion: Acrylamide exposure leads to adverse clinical pathologies of renal tubules, which were reversed by a concomitant treatment with 5-ASA and vitamin-E.
Dry Priming of Maize Seeds Reduces Aluminum Stress
Alcântara, Berenice Kussumoto; Machemer-Noonan, Katja; Silva Júnior, Francides Gomes; Azevedo, Ricardo Antunes
2015-01-01
Aluminum (Al) toxicity is directly related to acidic soils and substantially limits maize yield. Earlier studies using hormones and other substances to treat the seeds of various crops have been carried out with the aim of inducing tolerance to abiotic stress, especially chilling, drought and salinity. However, more studies regarding the effects of seed treatments on the induction of Al tolerance are necessary. In this study, two independent experiments were performed to determine the effect of ascorbic acid (AsA) seed treatment on the tolerance response of maize to acidic soil and Al stress. In the first experiment (greenhouse), the AsA seed treatment was tested in B73 (Al-sensitive genotype). This study demonstrates the potential of AsA for use as a pre-sowing seed treatment (seed priming) because this metabolite increased root and shoot growth under acidic and Al stress conditions. In the second test, the evidence from field experiments using an Al-sensitive genotype (Mo17) and an Al-tolerant genotype (DA) suggested that prior AsA seed treatment increased the growth of both genotypes. Enhanced productivity was observed for DA under Al stress after priming the seeds. Furthermore, the AsA treatment decreased the activity of oxidative stress-related enzymes in the DA genotype. In this study, remarkable effects using AsA seed treatment in maize were observed, demonstrating the potential future use of AsA in seed priming. PMID:26714286
Use of high temperature insulation for ceramic matrix composites in gas turbines
Morrison, Jay Alan; Merrill, Gary Brian; Ludeman, Evan McNeil; Lane, Jay Edgar
2001-01-01
A ceramic composition for insulating components, made of ceramic matrix composites, of gas turbines is provided. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere and the arrangement of spheres is such that the composition is dimensionally stable and chemically stable at a temperature of approximately 1600.degree. C. A stationary vane of a gas turbine comprising the composition of the present invention bonded to the outer surface of the vane is provided. A combustor comprising the composition bonded to the inner surface of the combustor is provided. A transition duct comprising the insulating coating bonded to the inner surface of the transition is provided. Because of abradable properties of the composition, a gas turbine blade tip seal comprising the composition also is provided. The composition is bonded to the inside surface of a shroud so that a blade tip carves grooves in the composition so as to create a customized seal for the turbine blade tip.
Studies of drag on the nanocomposite superhydrophobic surfaces
NASA Astrophysics Data System (ADS)
Brassard, Jean-Denis; Sarkar, D. K.; Perron, Jean
2015-01-01
The nanocomposite thin films of stearic acid (SA)-functionalized ZnO nanoparticles incorporated in epoxy polymer matrix have been achieved. The X-ray diffraction (XRD) studies show the formation of zinc stearate on ZnO nanoparticles as the confirmation of SA-functionalization of ZnO nanoparticles in the thin films. Morphological analyses reveal the presence of micro-holes with the presence of irregular nanoparticles. The measured root mean square (rms) roughness of the thin film is found to be 12 ± 1 μm with the adhesion of 5B on both glass and aluminum substrates. The wetting property shows that the surface of the film is superhydrophobic with the contact angle of water of 156 ± 4° having contact angle hysteresis (CAH) of 4 ± 2°. The average terminal velocity in the water of the as-received glass spheres and superhydrophobic spheres were found to be 0.66 ± 0.01 m/s and 0.72 ± 0.01 m/s respectively. Consequently, the calculated average coefficients of the surface drag of the as-received glass sphere and superhydrophobic glass sphere were 2.30 ± 0.01 and 1.93 ± 0.03, respectively. Hence, the drag reduction on the surface of superhydrophobic glass sphere is found to be approximately 16% lower than as-received glass sphere.
de Barros, João M S; Lechner, Tabea; Charalampopoulos, Dimitrios; Khutoryanskiy, Vitaliy V; Edwards, Alexander D
2015-09-30
We present a novel but simple enteric coated sphere formulation containing probiotic bacteria (Lactobacillus casei). Oral delivery of live bacterial cells (LBC) requires live cells to survive firstly manufacturing processes and secondly GI microbicidal defenses including gastric acid. We incorporated live L. casei directly in the granulation liquid, followed by granulation, extrusion, spheronization, drying and spray coating to produce dried live probiotic spheres. A blend of MCC, calcium-crosslinked alginate, and lactose was developed that gave improved live cell survival during manufacturing, and gave excellent protection from gastric acid plus rapid release in intestinal conditions. No significant loss of viability was observed in all steps except drying, which resulted in approximately 1 log loss of viable cells. Eudragit coating was used to protect dried live cells from acid, and microcrystalline cellulose (MCC) was combined with sodium alginate to achieve efficient sphere disintegration leading to rapid and complete bacterial cell release in intestinal conditions. Viability and release of L. casei was evaluated in vitro in simulated GI conditions. Uncoated spheres gave partial acid protection, but enteric coated spheres effectively protected dried probiotic LBC from acid for 2h, and subsequently released all viable cells within 1h of transfer into simulated intestinal fluid. Copyright © 2015 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Hongjing, E-mail: wuhongjing@mail.nwpu.edu.cn; Wu, Guanglei, E-mail: wuguanglei@mail.xjtu.edu.cn; Wu, Qiaofeng
2014-11-15
We reported the preparation of C@Ni–NiO core–shell hybrid solid spheres or multi-shelled NiO hollow spheres by combining a facile hydrothermal route with a calcination process in H{sub 2} or air atmosphere, respectively. The synthesized C@Ni–NiO core–shell solid spheres with diameters of approximately 2–6 μm were in fact built from dense NiO nanoparticles coated by random two-dimensional metal Ni nanosheets without any visible pores. The multi-shelled NiO hollow spheres were built from particle-like ligaments and there are a lot of pores with size of several nanometers on the surface. Combined Raman spectra with X-ray photoelectron spectra (XPS), it suggested that themore » defects in the samples play a limited role in the dielectric loss. Compared with the other samples, the permeability of the samples calcined in H{sub 2} and air was increased slightly and the natural resonance frequency shifted to higher frequency (7, 11 and 14 GHz, respectively), leading to an enhancement of microwave absorption property. For the sample calcined in H{sub 2}, an optimal reflection loss less than − 10 was obtained at 7 GHz with a matching thickness of 5.0 mm. Our study demonstrated the potential application of C@Ni–NiO core–shell hybrid solid sphere or multi-shelled NiO hollow sphere as a more efficient electromagnetic (EM) wave absorber. - Highlights: • C@Ni–NiO core–shell hybrid solid sphere was synthesized by a facile method. • Multi-shelled NiO hollow sphere was synthesized by a facile method. • It suggested that the defects in the samples play a limited role in dielectric loss. • The permeability of the samples calcined in H{sub 2} and air was increased. • Microwave absorbability of C@Ni–NiO core–shell hybrid solid sphere was investigated.« less
De Monte, Ariella; Brunetti, Davide; Cattin, Luigi; Lavanda, Francesca; Naibo, Erica; Malagoli, Maria; Stanta, Giorgio; Bonin, Serena
2018-03-01
Metformin, the drug of choice in the treatment of type 2 diabetes mellitus (DM2), in addition to aspirin (ASA), the drug prescribed for cardioprotection of diabetic and non-diabetic patients, have an inhibitory effect on cancer cell survival. The present population-based study conducted in the province of Trieste (Italy), aimed to investigate the prevalence of DM2 in patients with colorectal adenocarcinoma (CRC) and survival for CRC in diabetic and nondiabetic patients. All permanent residents diagnosed with a CRC between 2004 and 2007 were ascertained through the regional health information system. CRC-specific and relative survival probabilities were computed for each group of patients defined by CRC stage, presence or absence of DM2 treated with metformin, and presence or absence of daily ASA therapy. A total of 515 CRC patients without DM2 and 156 with DM2 treated with metformin were enrolled in the study. At the time of CRC diagnosis, 71 (14%) nondiabetic and 39 (25%) diabetic patients were taking ASA daily. The five-year relative survival for stage III CRC was 101% [95% confidence interval (CI)=76-126] in the 18 patients with DM2 treated with metformin and ASA, 55% (95% CI=31-78) in the 23 without DM2 treated with ASA, 55% (95% CI=45-65) in the 150 without DM2 not taking ASA, and 29% (95% CI=13-45) in the 43 with DM2 treated with metformin, however not with ASA. The findings support the hypothesis of a possible inhibitory effect of metformin and ASA on CRC cells. Randomized controlled trials are required to verify this hypothesis.
Ohwada, Ryouhei; Ozeki, Yu; Saitoh, Yasukazu
2017-01-01
High-dose ascorbic acid (AsA) treatment, known as pharmacological AsA, has been shown to exert carcinostatic effects in many types of cancer cells and in vivo tumour models. Although pharmacological AsA has potential as a complementary and alternative medicine for anticancer treatment, its effects on human tongue carcinoma have not yet been elucidated. In this study, we investigated the effect of AsA treatment on human tongue carcinoma HSC-4 cells compared with non-tumourigenic tongue epithelial dysplastic oral keratinocyte (DOK) cells. Our results show that treatment with 1 and 3 mM of AsA for 60 min preferentially inhibits the growth of human tongue carcinoma HSC-4 over DOK cells. Furthermore, AsA-induced effects were accompanied by increased intracellular oxidative stress and were repressed by treatment with a hydrogen peroxide (H 2 O 2 ) scavenger catalase and a superoxide anion radical (O 2 - ) scavenger, tempol. Time-lapse observation and thymidine analog EdU incorporation revealed that AsA treatment induces not only cell death but also suppression of DNA synthesis and cell growth. Moreover, the growth arrest was accompanied by abnormal cellular morphologies whereby cells extended dendrite-like pseudopodia. Taken together, our results demonstrate that AsA treatment can induce carcinostatic effects through induction of cell death, growth arrest, and morphological changes mediated by H 2 O 2 and O 2 - generation. These findings suggest that high-dose AsA treatment represents an effective treatment for tongue cancer as well as for other types of cancer cells.
Makowska, Joanna S; Olszewska-Ziąber, Agnieszka; Bieńkiewicz, Barbara; Lewandowska-Polak, Anna; Kurowski, Marcin; Woźniakowski, Bartłomiej; Rotkiewicz, Arkadiusz; Kowalski, Marek L
2016-05-01
Treatment with acetylsalicylic acid (ASA) after desensitization may be a therapeutic option in patients with nonsteroidal anti-inflammatory drug exacerbated respiratory disease (NERD). The mechanisms that lead to improvement in rhinosinusitis and asthma symptoms remain unknown. To attribute the documented clinical effects of ASA treatment of chronic rhinosinusitis and/or asthma to the release of eicosanoid metabolites in urine. Fourteen patients with NERD were successfully desensitized, and, eventually, eight patients were treated with 650 mg of ASA daily for 3 months. In addition to clinical assessments, nuclear magnetic resonance imaging and smell test were performed before and after treatment with ASA. Venous blood and urine were collected before desensitization and after 1 and 3 months of treatment. The levels of urinary leukotrienes (LT) (cysteinyl LT and LTE4) and tetranor PGDM (metabolite of prostaglandin D2) were measured by enzyme-linked immunosorbent assay. Treatment with ASA after desensitization alleviated symptoms of rhinosinusitis, improved nasal patency (mean, 50% decrease in peak nasal inspiratory flow) and sense of smell (fourfold increase in smell test score) in as early as 4 weeks. Clinical improvements were not accompanied by any change in sinonasal mucosa thickness as assessed with nuclear magnetic resonance. Urinary cysteinyl LTs, LTE4, and prostaglandin D2 metabolite remained relatively stable during ASA treatment and did not correlate with clinical improvements. Desensitization was associated with a progressive decrease of urinary creatinine. Clinical improvement in rhinosinusitis and/or asthma after ASA desensitization was not related to concentrations of urinary eicosanoid metabolites. A decrease of urinary creatinine requires further study to determine the renal safety of long-term treatment with ASA after desensitization.
Acetylsalicylic acid inhibits the pituitary response to exercise-related stress in humans.
Di Luigi, L; Guidetti, L; Romanelli, F; Baldari, C; Conte, D
2001-12-01
Prostaglandins (PGs) modulate the activity of the hypothalamus-pituitary axis, and pituitary hormones are largely involved in the physiological responses to exercise. The purpose of this study was to analyze the effects of acetylsalicylic acid (ASA), an inhibitor of PGs synthesis, in the pituitary responses to physical stress in humans. Adrenocorticotropin (ACTH), beta-endorphin, cortisol, growth hormone (GH), and prolactin (PRL) responses to exercise were evaluated after administration of either placebo or ASA. Blood samples for hormone evaluations before (-30, -15, and 0 pre) and after (0 post, +15, +30, +45, +60, and +90 min) a 30-min treadmill exercise (75% of .VO(2max)) were taken from 12 male athletes during two exercise trials. One tablet of ASA (800 mg), or placebo, was administered two times daily for 3 d before and on the morning of each exercise-test. The results clearly show that, compared with placebo, ASA ingestion significantly blunted the increased serum ACTH, beta-endorphin, cortisol, and GH levels before exercise (anticipatory response) and was associated with reduced cortisol concentrations after exercise. Furthermore, although no differences in the GH response to exercise were shown, a significantly reduced total PRL response to stress condition was observed after ASA. ASA influences ACTH, beta-endorphin, cortisol, GH, and PRL responses to exercise-related stress in humans (preexercise activation/exercise-linked response). Even though it is not possible to exclude direct action for ASA, our data indirectly confirm a role of PGs in these responses. We have to further evaluate the nature of the preexercise endocrine activation and, because of the large use of anti-inflammatory drugs in athletes, whether the interaction between ASA and hormones might positively or negatively influence health status, performance, and/or recovery.
Takeuchi, Koji; Takayama, Shinichi; Izuhara, Chitose
2014-08-21
The present study compared the effects of frequently used anti-platelet drugs, such as clopidogrel, ticlopidine, and cilostazol, on the gastric bleeding and ulcerogenic responses induced by intraluminal perfusion with 25 mM aspirin acidified with 25 mM HCl (acidified ASA) in rats. The stomach was perfused with acidified ASA at a rate of 0.4 ml/min for 60 min under urethane anesthesia, and gastric bleeding was measured as the concentration of hemoglobin in the luminal perfusate, which was collected every 15 min. Clopidogrel (10-100mg/kg), ticlopidine (10-300 mg/kg), or cilostazol (3-30 mg/kg) was given p.o. 24h or 90 min before the perfusion of acidified ASA, respectively. Perfusion of the stomach with acidified ASA alone led to slight bleeding and lesions in the stomach. The pretreatment with clopidogrel, even though it did not cause bleeding or damage by itself, dose-dependently increased the gastric bleeding and ulcerogenic responses induced by acidified ASA. Ticlopidine also aggravated the severity of damage by increasing gastric bleeding, and the effects of ticlopidine at 300 mg/kg were equivalent to those of clopidogrel at 100mg/kg. In contrast, cilostazol dose-dependently decreased gastric bleeding and damage in response to acidified ASA. These results demonstrated that clopidogrel and ticlopidine, P2Y12 receptor inhibitors, increased gastric bleeding and ulcerogenic responses to acidified ASA, to the same extent, while cilostazol, a phosphodiesterase III inhibitor, suppressed these responses. Therefore, cilostazol may be safely used in dual anti-platelet therapy combined with ASA, without increasing the risk of gastric bleeding. Copyright © 2014 Elsevier Inc. All rights reserved.
DiNicolantonio, James J; Serebruany, Victor L
2013-03-01
Ticagrelor, a novel reversible antiplatelet agent, has a Food and Drug Administration (FDA) black box warning to avoid maintenance doses of aspirin (ASA) >100 mg/daily. This restriction is based on the hypothesis that ASA doses >100 mg somehow decreased ticagrelor's benefit in the Platelet Inhibition and Patient Outcomes (PLATO) U.S. cohort. However, these data are highly postrandomized, come from a very small subgroup in PLATO (57% of patients in the U.S. site), and make no biological sense. Moreover, the ticagrelor-ASA interaction was not significant by any multivariate Cox regression analyses. The Complete Response Review for ticagrelor indicates that for U.S. PLATO patients, an ASA dose >300 mg was not a significant interaction for vascular outcomes. In the ticagrelor-ASA >300 mg cohort, all-cause and vascular mortality were not significantly increased (hazard ratio [HR] 1.27 [95% CI 0.84-1.93], P = 0.262 and 1.39 [0.87-2.2], P = 0.170), respectively. Furthermore, for major adverse cardiovascular events (MACEs), 30-day all-cause mortality, and 30-day vascular mortality, the strongest interaction is the diabetes-ASA interaction. That is, patients who had diabetes had significantly fewer MACEs through study end (0.49 [0.34-0.63], P < 0.0001), significantly less 30-day all-cause mortality (0.33 [0.20-0.56], P < 0.0001), and significantly less 30-day vascular mortality (0.35 [0.22-0.55], P < 0.0001), respectively, when given high-dose (300-325 mg) ASA, regardless of treatment (clopidogrel or ticagrelor) assignment. The black box warning for the use of maintenance ASA doses >100 mg with ticagrelor is inappropriate for patients with diabetes and not evidence based.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Jennie L.; Ji, Ping; Ouyang, Nengtai
Nitric oxide-donating aspirin (NO-ASA) is a promising agent for cancer prevention. Although studied extensively, its molecular targets and mechanism of action are still unclear. S-nitrosylation of signaling proteins is emerging as an important regulatory mechanism by NO. Here, we examined whether S-nitrosylation of the NF-{kappa}B, p53, and Wnt signaling proteins by NO-ASA might explain, in part, its mechanism of action in colon cancer. NO-ASA releases significant amounts of NO detected intracellularly in HCT116 and HT-29 colon cells. Using a modified biotin switch assay we demonstrated that NO-ASA S-nitrosylates the signaling proteins p53, {beta}-catenin, and NF-{kappa}B, in colon cancer cells inmore » a time- and concentration-dependent manner. NO-ASA suppresses NF-{kappa}B binding to its cognate DNA oligonucleotide, which occurs without changes in the nuclear levels of the NF-{kappa}B subunits p65 and p50 and is reversed by dithiothreitol that reduces -S-NO to -SH. In addition to S-nitrosylation, we documented both in vitro and in vivo widespread nitration of tyrosine residues of cellular proteins in response to NO-ASA. Our results suggest that the increased intracellular NO levels following treatment with NO-ASA modulate cell signaling by chemically modifying key protein members of signaling cascades. We speculate that S-nitrosylation and tyrosine nitration are responsible, at least in part, for the inhibitory growth effect of NO-ASA on cancer cell growth and that this may represent a general mechanism of action of NO-releasing agents.« less
NASA Technical Reports Server (NTRS)
Glownia, James H.; Sorokin, Peter P.
1994-01-01
In this paper, a new model is proposed to account for the DIB's (Diffuse Interstellar Bands). In this model, the DIB's result from a non-linear effect: resonantly-enhanced two-photon absorption of H(2+) ions located near the surface of the Stromgren sphere that surrounds an O- or B- type star. The strong light that is required to 'drive' the two-photon transition is provided by L(alpha) light emerging from the Stromgren sphere that bounds the H II region surrounding the star. A value of approximately 100 micro W/sq cm is estimated for the L(alpha) flux at the Stromgren radius, R(s), of a strong (O5) star. It is shown that a c.w. L(alpha) flux of this intensity should be sufficient to induce a few percent absorption for visible light radiated by the same star at a frequency (omega2) that completes an allowed two-photon transition, provided (1) the L(alpha) radiation happens to be nearly resonant with the frequency of a fully-allowed absorber transition that effectively represents the first step in the two-photon transition, and (2) an effective column density approximately 10(sup18)/sq cm of the absorber is present near the Stromgren sphere radius, R(sub s).
On the Concentration Gradient across a Spherical Source Washed by Slow Flow
Jaffe, Lionel
1965-01-01
A model has been numerically analyzed to help interpret the orienting effects of flow upon cells. The model is a sphere steadily and uniformly emitting a diffusible stuff into a medium otherwise free of it and moving past with Stokes flow. Its properties depend primarily upon the Peclet number, Pe, equal to a · v∞/D, i.e., the sphere's radius, a, times the free stream speed, v∞, over the stuff's diffusion constant, D. As Pe rises, and washing becomes more effective, the average surface concentration, C̄s a falls (Figs. 2 and 5) and the residual material becomes relatively concentrated on the sphere's lee pole (Figs. 2 and 4). Specifically, as Pe rises from 0.1 to 1, the relative concentration gradient, G, rises from 0.7 to 5.0 per cent and to the point where it is rising at about 8 per cent per decade; by Pe 1000, G = 22.1 per cent. From Pe 1 through 1000, G/(1 - C̄s a), or the gradient per concentration deficiency remains at about 26 per cent suggesting that G approaches a ceiling of about 26 per cent. Also from Pe 1 through 1000, the average mass transfer co-efficient nearly equals that previously calculated for spheres maintaining constant surface concentration instead of flux. The complete differential equation without approximations, the Gauss-Seidel method, and an approximation for the outer boundary condition were used. PMID:14268954
NASA Astrophysics Data System (ADS)
Tessarotto, Massimo; Asci, Claudio
2017-05-01
In this paper the problem is posed of determining the physically-meaningful asymptotic orderings holding for the statistical description of a large N-body system of hard spheres, i.e., formed by N ≡1/ε ≫ 1 particles, which are allowed to undergo instantaneous and purely elastic unary, binary or multiple collisions. Starting point is the axiomatic treatment recently developed [Tessarotto et al., 2013-2016] and the related discovery of an exact kinetic equation realized by Master equation which advances in time the 1-body probability density function (PDF) for such a system. As shown in the paper the task involves introducing appropriate asymptotic orderings in terms of ε for all the physically-relevant parameters. The goal is that of identifying the relevant physically-meaningful asymptotic approximations applicable for the Master kinetic equation, together with their possible relationships with the Boltzmann and Enskog kinetic equations, and holding in appropriate asymptotic regimes. These correspond either to dilute or dense systems and are formed either by small-size or finite-size identical hard spheres, the distinction between the various cases depending on suitable asymptotic orderings in terms of ε.
CONSISTENCY AND THE FIFTH VIRIAL COEFFICIENT FOR A HARD-SPHERE GAS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cole, G.H.A.
1962-03-15
The modified superposition approximation g(/sup 3/)(r,s,t) = g(.syo 2)(r/ sup 2/g(/sup 2/)(s)g(/sup 2/)(t)STAl + X/sub 1/n + X/sub 2/n/sup 2/!(where g/sup (3)/si the triplet distribution, g(/sup 2/) the pair distribution, n the number density, and (r,s,t) are the particle separation distances) is used in conjunction with the Born-Green-Yvon equation of the classical theory of fluids in the calculation of the fifth virial coefficient E for a gas of hard spheres. The values of E derived directly from the virial theorem and alternatively from compressibility arguments are reconciled through a suitable choice of X/sub 2/. On the assumption X/sub i/ =more » constant it is found for hard spheres that X/sub 1/ = 0.1014b and X/sub 2/ = -0.0424b/sub 2/ (b = four times a molecular volume) ensures consistency as far as the fifth virial coefficient. The consistent value of E under this approximation is +0.0242b/sup 4/. The validity of the arguments is considered. (auth)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Medasani, Bharat; Ovanesyan, Zaven; Thomas, Dennis G.
In this article we present a classical density functional theory for electrical double layers of spherical macroions that extends the capabilities of conventional approaches by accounting for electrostatic ion correlations, size asymmetry and excluded volume effects. The approach is based on a recent approximation introduced by Hansen-Goos and Roth for the hard sphere excess free energy of inhomogeneous fluids (J. Chem. Phys. 124, 154506). It accounts for the proper and efficient description of the effects of ionic asymmetry and solvent excluded volume, especially at high ion concentrations and size asymmetry ratios including those observed in experimental studies. Additionally, we utilizemore » a leading functional Taylor expansion approximation of the ion density profiles. In addition, we use the Mean Spherical Approximation for multi-component charged hard sphere fluids to account for the electrostatic ion correlation effects. These approximations are implemented in our theoretical formulation into a suitable decomposition of the excess free energy which plays a key role in capturing the complex interplay between charge correlations and excluded volume effects. We perform Monte Carlo simulations in various scenarios to validate the proposed approach, obtaining a good compromise between accuracy and computational cost. We use the proposed computational approach to study the effects of ion size, ion size asymmetry and solvent excluded volume on the ion profiles, integrated charge, mean electrostatic potential, and ionic coordination number around spherical macroions in various electrolyte mixtures. Our results show that both solvent hard sphere diameter and density play a dominant role in the distribution of ions around spherical macroions, mainly for experimental water molarity and size values where the counterion distribution is characterized by a tight binding to the macroion, similar to that predicted by the Stern model.« less
Gilmore, Amanda K; Koo, Kelly H; Nguyen, Hong V; Granato, Hollie F; Hughes, Tonda L; Kaysen, Debra
2014-03-01
Childhood sexual abuse (CSA) and adolescent/adult sexual assault (ASA) are strongly associated with women's alcohol use and the rates of both alcohol use and sexual assault history are higher among lesbian and bisexual women than heterosexual women. Although descriptive drinking norms are one of the highest predictors of alcohol use in emerging adults, this is the first study to examine the relationship between sexual assault history, drinking norms, and alcohol use in lesbian and bisexual women. We found that CSA severity was associated with a higher likelihood of experiencing more severe alcohol-involved ASA, more severe physically forced ASA, and was indirectly associated with more drinking behavior and higher drinking norms. Additionally, more severe alcohol-involved ASA was associated with higher drinking norms and more drinking behavior, but physically forced ASA was not. These findings help explain previous contradictory findings and provide information for interventions. Published by Elsevier Ltd.
Gilmore, Amanda K.; Koo, Kelly H.; Nguyen, Hong V.; Granato, Hollie F.; Hughes, Tonda L.; Kaysen, Debra L.
2014-01-01
Childhood sexual abuse (CSA) and adolescent/adult sexual assault (ASA) are strongly associated with women’s alcohol use and the rates of both alcohol use and sexual assault history are higher among lesbian and bisexual women than heterosexual women. Although descriptive drinking norms are one of the highest predictors of alcohol use in emerging adults, this is the first study to examine the relationship between sexual assault history, drinking norms, and alcohol use in lesbian and bisexual women. We found that CSA severity was associated with a higher likelihood of experiencing more severe alcohol-involved ASA, more severe physically forced ASA, and was indirectly associated with more drinking behavior and higher drinking norms. Additionally, more severe alcohol-involved ASA was associated with higher drinking norms and more drinking behavior, but physically forced ASA was not. These findings help explain previous contradictory findings and provide information for interventions. PMID:24360780
NASA Astrophysics Data System (ADS)
Shahabadi, Nahid; Fili, Soraya Moradi
2014-01-01
The interaction of mesalamine (5-aminosalicylic acid (5-ASA)) with bovine serum albumin (BSA) was investigated by fluorescence quenching, absorption spectroscopy, circular dichroism (CD) techniques, and molecular docking. Thermodynamic parameters (ΔH < 0 and ΔS 0) indicated that the hydrogen bond and electrostatic forces played the major role in the binding of 5-ASA to BSA. The results of CD and UV-vis spectroscopy showed that the binding of this drug to BSA induces some conformational changes in BSA. Displacement experiments predicted that the binding of 5-ASA to BSA is located within domain III, Sudlows site 2, that these observations were substantiated by molecular docking studies. In addition, the docking result shows that the 5-ASA in its anionic form mainly interacts with Gln-416 residue through one hydrogen bond between H atom of 5-ASA anion and the adjacent O atom of the hydroxyl group of Gln-416.
Self-interaction correction in multiple scattering theory: application to transition metal oxides
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daene, Markus W; Lueders, Martin; Ernst, Arthur
2009-01-01
We apply to transition metal monoxides the self-interaction corrected (SIC) local spin density (LSD) approximation, implemented locally in the multiple scattering theory within the Korringa-Kohn-Rostoker (KKR) band structure method. The calculated electronic structure and in particular magnetic moments and energy gaps are discussed in reference to the earlier SIC results obtained within the LMTO-ASA band structure method, involving transformations between Bloch and Wannier representations to solve the eigenvalue problem and calculate the SIC charge and potential. Since the KKR can be easily extended to treat disordered alloys, by invoking the coherent potential approximation (CPA), in this paper we compare themore » CPA approach and supercell calculations to study the electronic structure of NiO with cation vacancies.« less
The unstaggered extension to GFDL's FV3 dynamical core on the cubed-sphere
NASA Astrophysics Data System (ADS)
Chen, X.; Lin, S. J.; Harris, L.
2017-12-01
Finite-volume schemes have become popular for atmospheric transport since they provide intrinsic mass conservation to constituent species. Many CFD codes use unstaggered discretizations for finite volume methods with an approximate Riemann solver. However, this approach is inefficient for geophysical flows due to the complexity of the Riemann solver. We introduce a Low Mach number Approximate Riemann Solver (LMARS) simplified using assumptions appropriate for atmospheric flows: the wind speed is much slower than the sound speed, weak discontinuities, and locally uniform sound wave velocity. LMARS makes possible a Riemann-solver-based dynamical core comparable in computational efficiency to many current dynamical cores. We will present a 3D finite-volume dynamical core using LMARS in a cubed-sphere geometry with a vertically Lagrangian discretization. Results from standard idealized test cases will be discussed.
Standards 101; the ASA standards program
NASA Astrophysics Data System (ADS)
Schomer, Paul D.
2002-11-01
ASA supports the development of standards by serving as the secretariat for standards committees of the American National Standards Institute (ANSI). The program is organized through four ANSI technical committees (S1, S2, S3, and S12) and one administrative committee (ASACOS). S1 deals with physical acoustics, S2 deals with shock and vibration, S3 deals with physiological and psychological acoustics, and S12 deals with noise. ASACOS is the ASA Committee on Standards. The program has three primary tasks: (1) the development of National Standards (ANSI Standards), (2) the national adoption of an international standard (ANSI NAIS Standards), (3) providing the USA input to the development of International Standards (ISO and IEC Standards). At every level the main work is accomplished in Working Groups (WG) that are ''staffed'' by hundreds of volunteers--mainly ASA members from its various technical committees such as Noise, Physical Acoustics, Architectural Acoustics, Psychological and Physiological Acoustics, etc. Overall, the Standards Program involves more ASA members than does any other single function of the Society except meetings and it is the biggest outreach function of ASA affecting the health, welfare, and economic well-being of large segments of the population, the business and industrial community, and government at all levels.
Crestoni, Maria Elisa; Chiavarino, Barbara; Guglielmo, Stefano; Lilla, Valentina; Fornarini, Simonetta
2013-01-01
Aspirin (acetylsalicylic acid, ASA) is the most popular non-steroidal anti-inflammatory drug. However, due to its action on cyclooxygenase and its acid nature, aspirin is associated with adverse gastrointestinal effects. In an effort to minimize these side effects, NO-donor and H2S-donor ASA co-drugs have been designed and tested. Their mass spectrometric behavior is now analyzed and reported. Positive ions were obtained by electrospray ionization involving protonation or alkali metal attachment. Their dissociation processes have been studied by collision induced dissociation in a triple quadrupole instrument. High mass accuracy measurements have been recorded on a Fourier transform ion cyclotron resonance mass spectrometer. The protonated molecules dissociate by an exclusive or largely prevailing path leading to acetyloxy-substituted benzoyl cation, namely an ASA unit. The process is reminiscent of the enzymatic hydrolysis, releasing intact ASA to a large extent. Only at higher collision energy does the formal ketene loss disrupt the ASA moiety. The gas phase chemistry of protonated ASA-releasing drugs develops along elementary dissociation steps analogous to the reactive processes in complex biological environments. This notion may provide a tool for preliminary testing of new compounds.
[Effects of exogenous AsA and GSH on the growth of Dianthus chinensis seedlings exposed to Cd].
Ding, Ji-Jun; Liu, Shi-Liang; Pan, Yuan-Zhi; Li, Li
2014-02-01
A pot experiment was carried out under greenhouse condition to investigate the effects of different concentrations (0, 20, 40, 60, 80 and 100 mg x L(-1)) of exogenous AsA, GSH on Dianthus chinensis seedlings which were stressed by 50 mg x kg(-1) Cd in the soil. The results indicated that 50 mg x kg(-1) of Cd significantly inhibited the growth of D. chinensis seedlings. An appropriate concentration of exogenous AsA significantly improved the biomass, plant height, tiller number, GAT and APX activities, and AsA and GSH contents. However, with the increase of exogenous AsA concentration, the ameliorating effect decreased and prooxidant effect occurred. Exogenous GSH could replenish the non-enzymatic antioxidants of D. chinensis seedlings, but the changes of antioxidant enzyme activities were relatively slight. The main mechanisms of GSH to alleviate Cd toxicity might be promoting root PCs synthesis, thereby reducing the Cd concentration in the seedlings. Both 35-45 mg x L(-1) exogenous AsA and 55-65 mg x L(-1) exogenous GSH could alleviate the Cd toxicity on D. chinensis seedlings, and the former was superior to the latter.
Variability in the American Society of Anesthesiologists Physical Status Classification Scale.
Aronson, Wendy L; McAuliffe, Maura S; Miller, Ken
2003-08-01
The American Society of Anesthesiologists (ASA) Physical Status (PS) Classification is used worldwide by anesthesia providers as an assessment of the preoperative physical health of patients. This score also has been used in policy-making, performance evaluation, resource allocation, and reimbursement of anesthesia services and frequently is cited in clinical research. The purpose of this study was to assess interrater reliability and describe sources of variability among anesthesia providers in assigning ASA PS scores. A questionnaire with 10 hypothetical patients scenarios was given to 70 anesthesia providers who were asked to assign ASA PS scores in each scenario and to provide rationale for their decisions. The data were summarized and stratified according to nurse anesthetist or anesthesiologist and military or nonmilitary anesthesia providers. We hypothesized there would be no difference between any of the anesthesia provider groups in assignment of ASA PS scores. A lack of interrater reliability in assigning ASA PS scores was demonstrated. There were no significant differences between the anesthesia provider groups. There was no correlation between ASA PS scoring and years practicing or any of the other demographic variables. Several sources of variability were identified: smoking, pregnancy, nature of the surgery, potential difficult airway, and acute injury.
Ikeda, Y; Kikuchi, M; Murakami, H; Satoh, K; Murata, M; Watanabe, K; Ando, Y
1987-05-01
A randomized double-blind cross-over study was conducted to determine the inhibitory effects of acetylsalicylic acid (ASA), ticlopidine (TP) and cilostazol (OPC-13013; in the following briefly called CS), a new antithrombotic agent on platelet functions ex vivo. Nine patients with cerebral thrombosis were enrolled in this study. Patients were given each of the three drugs for one week in a complete cross-over design according to a randomization schedule, followed by a wash-out period with a placebo for one week. It was found that CS and TP significantly inhibited platelet aggregation induced by ADP. Collagen- and arachidonic acid-induced platelet aggregation was all inhibited by CS, TP and ASA. Duncan's multiple range test to compare the anti-platelet effects of the three drugs revealed that: CS greater than ASA and TP greater than ASA in inhibiting ADP-induced platelet aggregation and CS greater than TP and ASA greater than TP in inhibiting arachidonic acid-induced platelet aggregation. These results may suggest that CS is superior to ASA and TP in inhibiting platelet aggregation ex vivo.
Yu, Alex; Baker, Jason R; Fioritto, Ann F; Wang, Ying; Luo, Ruijuan; Li, Siwei; Wen, Bo; Bly, Michael; Tsume, Yasuhiro; Koenigsknecht, Mark J; Zhang, Xinyuan; Lionberger, Robert; Amidon, Gordon L; Hasler, William L; Sun, Duxin
2017-02-06
As an orally administered, locally acting gastrointestinal drug, mesalamine products are designed to achieve high local drug concentration in the gastrointestinal (GI) tract for the treatment of ulcerative colitis. The aim of this study was to directly measure and compare drug dissolution of three mesalamine formulations in human GI tract and to correlate their GI concentration with drug concentration in plasma. Healthy human subjects were orally administered Pentasa, Apriso, or Lialda. GI fluids were aspirated from stomach, duodenum, proximal jejunum, mid jejunum, and distal jejunum regions. Mesalamine (5-ASA) and its primary metabolite acetyl-5-mesalamine (Ac-5-ASA) were measured using LC-MS/MS. GI tract pH was measured from each GI fluid sample, which averaged 1.82, 4.97, 5.67, 6.17, and 6.62 in the stomach, duodenum, proximal jejunum, middle jejunum, and distal jejunum, respectively. For Pentasa, high levels of 5-ASA in solution were observed in the stomach, duodenum, proximal jejunum, mid jejunum, and distal jejunum from 1 to 7 h. Apriso had minimal 5-ASA levels in stomach, low to medium levels of 5-ASA in duodenum and proximal jejunum from 4 to 7 h, and high levels of 5-ASA in distal jejunum from 3 to 7 h. In contrast, Lialda had minimal 5-ASA levels from stomach and early small intestine. A composite appearance rate (CAR) was calculated from the deconvolution of individual plasma concentration to reflect drug release, dissolution, transit, and absorption in the GI tract. Individuals dosed with Pentasa had high levels of CAR from 1 to 10 h; individuals dosed with Apriso had low levels of CAR from 1 to 4 h and high levels of CAR from 5 to 10 h; Lialda showed minimal levels of CAR from 0 to 5 h, then increased to medium levels from 5 to 12 h, and then decreased to further lower levels after 12 h. In the colon region, Pentasa and Apriso showed similar levels of accumulated 5-ASA excreted in the feces, while Lialda showed slightly higher 5-ASA accumulation in feces. However, all three formulations showed similar levels of metabolite Ac-5-ASA in the feces. These results provide direct measurement of drug dissolution in the GI tract, which can serve as a basis for investigation of bioequivalence for locally acting drug products.
Linear and nonlinear response in sheared soft spheres
NASA Astrophysics Data System (ADS)
Tighe, Brian
2013-11-01
Packings of soft spheres provide an idealized model of foams, emulsions, and grains, while also serving as the canonical example of a system undergoing a jamming transition. Packings' mechanical response has now been studied exhaustively in the context of ``strict linear response,'' i.e. by linearizing about a stable static packing and solving the resulting equations of motion. Both because the system is close to a critical point and because the soft sphere pair potential is non-analytic at the point of contact, it is reasonable to ask under what circumstances strict linear response provides a good approximation to the actual response. We simulate sheared soft sphere packings close to jamming and identify two distinct strain scales: (i) the scale on which strict linear response fails, coinciding with a topological change in the packing's contact network; and (ii) the scale on which linear superposition of the averaged stress-strain curve breaks down. This latter scale provides a ``weak linear response'' criterion and is likely to be more experimentally relevant.
Pauling, L
1991-02-01
Whereas 234(92)U142 and other actinon nuclei have ground-state bands that indicate that each nucleus consists of a sphere and a single revolving cluster with constant composition and with only a steady increase in the moment of inertia with increase in J, the angular-momentum quantum number, many of the lanthanon ground-state bands show discontinuities, usually with an initial slightly or strongly curved segment followed by one or two nearly straight segments. The transition to nearly straight segments is interpreted as a change in structure from one revolving cluster to two revolving clusters. The proton-neutron compositions of the clusters and the central sphere are assigned, leading to values of the radius of revolution. The approximation of the two-cluster sequences to linearity is attributed to the very small values of the quadrupole polarizability of the central sphere. Values of the nucleon numbers of clusters and spheres, of the radius of revolution, and of promotion energy are discussed.
Santillan, Arturo O; Cutanda-Henríquez, Vicente
2008-11-01
An investigation on the resonance frequency shift for a plane-wave mode in a cylindrical cavity produced by a rigid sphere is reported in this paper. This change of the resonance frequency has been previously considered as a cause of oscillational instabilities in single-mode acoustic levitation devices. It is shown that the use of the Boltzmann-Ehrenfest principle of adiabatic invariance allows the derivation of an expression for the resonance frequency shift in a simpler and more direct way than a method based on a Green's function reported in literature. The position of the sphere can be any point along the axis of the cavity. Obtained predictions of the resonance frequency shift with the deduced equation agree quite well with numerical simulations based on the boundary element method. The results are also confirmed by experiments. The equation derived from the Boltzmann-Ehrenfest principle appears to be more general, and for large spheres, it gives a better approximation than the equation previously reported.
Coulomb energy of uniformly charged spheroidal shell systems.
Jadhao, Vikram; Yao, Zhenwei; Thomas, Creighton K; de la Cruz, Monica Olvera
2015-03-01
We provide exact expressions for the electrostatic energy of uniformly charged prolate and oblate spheroidal shells. We find that uniformly charged prolate spheroids of eccentricity greater than 0.9 have lower Coulomb energy than a sphere of the same area. For the volume-constrained case, we find that a sphere has the highest Coulomb energy among all spheroidal shells. Further, we derive the change in the Coulomb energy of a uniformly charged shell due to small, area-conserving perturbations on the spherical shape. Our perturbation calculations show that buckling-type deformations on a sphere can lower the Coulomb energy. Finally, we consider the possibility of counterion condensation on the spheroidal shell surface. We employ a Manning-Oosawa two-state model approximation to evaluate the renormalized charge and analyze the behavior of the equilibrium free energy as a function of the shell's aspect ratio for both area-constrained and volume-constrained cases. Counterion condensation is seen to favor the formation of spheroidal structures over a sphere of equal area for high values of shell volume fractions.
Fan, Xingjun; Monnier, Vincent M
2008-11-01
Senile cataracts are associated with oxidation, fragmentation, cross-linking, insolubilization, and yellow pigmentation of lens crystallins. This process is partially explained by advanced glycation end products (AGEs) from ascorbic acid (ASA), as the authors unequivocally demonstrated in an hSVCT2 transgenic mouse. The authors present the first pharmacologic intervention study against ascorbylation in these mice. Five groups of mice from 2 to 9 months of age (10 mice/group) were fed a diet containing 0.1% (wt/wt) aminoguanidine, pyridoxamine, penicillamine, and nucleophilic compounds NC-I and NC-II. AGEs were determined in crystallin digests using high-performance liquid chromatography, liquid chromatography-mass spectrometry, or gas chromatography-mass spectrometry. Lens protein extract was incubated in vitro with ASA or dehydroascorbic acid. The ASA level increased approximately 10-fold in all groups and was unaffected by treatment. AGEs were increased several-fold in transgenic compared with control lenses. Body weight, food intake, lenticular glutathione, and glycated lysine level were unaltered. In vitro, all compounds inhibited AGE formation. In vivo, NC-I and NC-II significantly decreased protein fluorescence at lambda(ex)335/(em)385 (P = 0.045, P = 0.017, respectively) and lambda(ex)370/(em)440 (P = 0.029, P = 0.007, respectively). Other inhibitors had no effect. After 7 months, only NC-I and NC-II induced a 50% reduction in pentosidine (P = NS for NC-I; P = 0.035 for NC-II). NC-I also decreased carboxymethyllysine (P = 0.032) and carboxyethyllysine (P = NS). Fluorescent cross-link K2P was decreased by NC-I, NC-II, aminoguanidine, and pyridoxamine (P = NS). Pharmacologically blocking protein ascorbylation with absorbable guanidino compounds is feasible and may represent a new strategy for the delay of age-related nuclear sclerosis of the lens.
Saucedo-Velez, A A; Hinojosa-Reyes, L; Villanueva-Rodríguez, M; Caballero-Quintero, A; Hernández-Ramírez, A; Guzmán-Mar, J L
2017-10-01
The development of a new method to determine the presence of the organoarsenic additives p-arsanilic acid (ASA), roxarsone (ROX) and nitarsone (NIT) in livestock feeds by high performance liquid chromatography coupled to ultraviolet oxidation hydride generation atomic fluorescence spectrometry (HPLC-UV/HG-AFS) after microwave assisted extraction (MAE) was proposed. Chromatographic separation was achieved on a C18 column with 2% acetic acid/methanol (96:4, v/v) as the mobile phase. The limits of detection (LODs) were 0.13, 0.09 and 0.08mgL -1 , and the limits of quantification (LOQs) were 0.44, 0.30 and 0.28mgL -1 . The relative standard deviations (RSDs) for ASA, ROX and NIT determined from five measurements of the mixed calibration standard were 3.3, 5.3, and 5.4%, respectively. MAE extraction of phenylated arsenic compounds using 1.5M H 3 PO 4 at 120°C for 45min allowed for maximum recoveries (%) of total arsenic (As) and organoarsenic species, with no degradation of these compounds. The extraction of total As was approximately 97%, and the As species recoveries were between 95.2 and 97.0%. The results of the analysis were validated using mass balance by comparing the sum of extracted As with the total concentration of As in the corresponding samples. The method was successfully applied to determine the presence of these compounds in feed samples. ASA was the only As species detected in chicken feed samples, with a concentration between 0.72 and 12.91mgkg -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.
Neuberger, Sabine; Jooß, Kevin; Flottmann, Dirk; Scriba, Gerhard; Neusüß, Christian
2017-02-05
In order to ensure the stability of pharmaceutical products appropriate manufacturing and storage conditions are required. In general, the degradation of active pharmaceutical ingredients (APIs) and subsequent formation of degradation products affect the pharmaceutical quality. Thus, a fast and effective detection and characterization of these substances is mandatory. Here, the applicability of Raman spectroscopy and CZE for the characterization of the degradation of effervescent tablets containing acetylsalicylic acid (ASA) and ascorbic acid (AA) was evaluated. Therefore, a degradation study was performed analyzing tablets from two different manufacturers at varying conditions (relative humidity (RH) 33%, 52% and 75% at 30°C). Raman spectroscopy combined with principal component analysis could be successfully applied for the fast and easy discrimination of non-degraded and degraded effervescent tablets after a storage period of approximately 24h (RH 52%). Nevertheless, a clear identification or quantification of APIs and degradation products within the analyzed tablets was not possible, i.a. due to missing reference materials. CZE-UV enabled the quantification of the APIs (ASA, AA) and related degradation products (salicylic acid (SA); semi-quantitative also mono- and diacetylated AA) within the complex tablet mixtures. The higher the RH, the faster the degradation of ASA and AA as well as the formation of the degradation products. Mono- and diacetylated AA are major primary degradation products of AA for the applied effervescent tablets. A significant degradation of the APIs was detected earlier by CZE (6-12h, RH 52%) than by Raman spectroscopy. Summarized, Raman spectroscopy is well-suited as quick test to detect degradation of these tablets and CZE can be utilized for further detailed characterization and quantification of specific APIs and related degradation products. Copyright © 2016 Elsevier B.V. All rights reserved.
Zernova, Olga; Zhong, Wei; Zhang, Xing-Hai; Widholm, Jack
2008-11-01
This study was carried out to determine if the tobacco anthranilate synthase ASA2 2.3 kb promoter drives tissue culture specific expression and if it is strong enough to drive hpt (hygromycin phosphotransferase) gene expression at a level sufficient to allow selection of transformed soybean embryogenic culture lines. A number of transformed cell lines were selected showing that the promoter was strong enough. Northern blot analysis of plant tissues did not detect hpt mRNA in the untransformed control or in the ASA2-hpt plants except in developing seeds while hpt mRNA was detected in all tissues of the CaMV35S-hpt positive control line plants. However, when the more sensitive RT-PCR assay was used all tissues of the ASA2-hpt plants except roots and mature seeds were found to contain detectable hpt mRNA. Embryogenic tissue cultures initiated from the ASA2-hpt plants contained hpt mRNA detectable by both northern and RT-PCR analysis and the cultures were hygromycin resistant. Friable callus initiated from leaves of ASA2-hpt plants did in some cases contain hpt mRNA that was only barely detectable by northern hybridization even though the callus was very hygromycin resistant. Thus the ASA2 promoter is strong enough to drive sufficient hpt expression in soybean embryogenic cultures for hygromycin selection and only very low levels of expression were found in most plant tissues with none in mature seeds.
NASA Astrophysics Data System (ADS)
Han, Hee-Siew; Chen, Da-Ren; Pui, David Y. H.; Anderson, Bruce E.
2000-03-01
We have developed a fast-response nanometer aerosol size analyzer (nASA) that is capable of scanning 30 size channels between 3 and 100 nm in a total time of 3 s. The analyzer includes a bipolar charger (Po210), an extended-length nanometer differential mobility analyzer (Nano-DMA), and an electrometer (TSI 3068). This combination of components provides particle size spectra at a scan rate of 0.1 s per channel free of uncertainties caused by response-time-induced smearing. The nASA thus offers a fast response for aerosol size distribution measurements in high-concentration conditions and also eliminates the need for applying a de-smearing algorithm to resulting data. In addition, because of its thermodynamically stable means of particle detection, the nASA is useful for applications requiring measurements over a broad range of sample pressures and temperatures. Indeed, experimental transfer functions determined for the extended-length Nano-DMA using the tandem differential mobility analyzer (TDMA) technique indicate the nASA provides good size resolution at pressures as low as 200 Torr. Also, as was demonstrated in tests to characterize the soot emissions from the J85-GE engine of a T-38 aircraft, the broad dynamic concentration range of the nASA makes it particularly suitable for studies of combustion or particle formation processes. Further details of the nASA performance as well as results from calibrations, laboratory tests and field applications are presented below.
NASA Astrophysics Data System (ADS)
Usman, Aliyu; Ibrahim, Muhammad B.; Bala, Nura
2018-04-01
This research is aimed at investigating the effect of using amorphous silica ash (ASA) obtained from rice husk as a partial replacement of ordinary Portland cement (OPC) on the compressive and flexural strength of mortar. ASA was used in partial replacement of ordinary Portland cement in the following percentages 2.5 percent, 5 percent, 7.5 percent and 10 percent. These partial replacements were used to produce Cement-ASA mortar. ASA was found to contain all major chemical compounds found in cement with the exception of alumina, which are SiO2 (91.5%), CaO (2.84%), Fe2O3 (1.96%), and loss on ignition (LOI) was found to be 9.18%. It also contains other minor oxides found in cement. The test on hardened mortar were destructive in nature which include flexural strength test on prismatic beam (40mm x 40mm x 160mm) and compressive strength test on the cube size (40mm x 40mm, by using the auxiliary steel plates) at 2,7,14 and 28 days curing. The Cement-ASA mortar flexural and compressive strengths were found to be increasing with curing time and decreases with cement replacement by ASA. It was observed that 5 percent replacement of cement with ASA attained the highest strength for all the curing ages and all the percentage replacements attained the targeted compressive strength of 6N/mm2 for 28 days for the cement mortar
NASA Technical Reports Server (NTRS)
Han, Hee-Siew; Chen, Da-Ren; Pui, David Y. H.; Anderson, Bruce E.
2001-01-01
We have developed a fast-response Nanometer Aerosol Size Analyzer (nASA) that is capable of scanning 30 size channels between 3 and 100 nm in a total time of 3 seconds. The analyzer includes a bipolar charger (P0210), an extended-length Nanometer Differential Mobility Analyzer (Nano-DMA), and an electrometer (TSI 3068). This combination of components provides particle size spectra at a scan rate of 0.1 second per channel free of uncertainties caused by response-time-induced smearing. The nASA thus offers a fast response for aerosol size distribution measurements in high-concentration conditions and also eliminates the need for applying a de-smearing algorithm to resulting data. In addition, because of its thermodynamically stable means of particle detection, the nASA is useful for applications requiring measurements over a broad range of sample pressures and temperatures. Indeed, experimental transfer functions determined for the extended-length Nano-DMA using the Tandem Differential Mobility Analyzer (TDMA) technique indicate the nASA provides good size resolution at pressures as low as 200 Torr. Also, as was demonstrated in tests to characterize the soot emissions from the J85-GE engine of a T38 aircraft, the broad dynamic concentration range of the nASA makes it particularly suitable for studies of combustion or particle formation processes. Further details of the nASA performance as well as results from calibrations, laboratory tests and field applications are presented.
Central effects of acetylsalicylic acid on trigeminal-nociceptive stimuli
2014-01-01
Background Acetylsalicylic acid is one of the most used analgesics to treat an acute migraine attack. Next to the inhibitory effects on peripheral prostaglandin synthesis, central mechanisms of action have also been discussed. Methods Using a standardized model for trigeminal-nociceptive stimulation during fMRI scanning, we investigated the effect of acetylsalicylic acid on acute pain compared to saline in 22 healthy volunteers in a double-blind within-subject design. Painful stimulation was applied using gaseous ammonia and presented in a pseudo-randomized order with several control stimuli. All participants were instructed to rate the intensity and unpleasantness of every stimulus on a VAS scale. Based on previous results, we hypothesized to find an effect of ASA on central pain processing structures like the ACC, SI and SII as well as the trigeminal nuclei and the hypothalamus. Results Even though we did not find any differences in pain ratings between saline and ASA, we observed decreased BOLD signal changes in response to trigemino-nociceptive stimulation in the ACC and SII after administration of ASA compared to saline. This finding is in line with earlier imaging results investigating the effect of ASA on acute pain. Contrary to earlier findings from animal studies, we could not find an effect of ASA on the trigeminal nuclei in the brainstem or within the hypothalamic area. Conclusion Taken together our study replicates earlier findings of an attenuating effect of ASA on pain processing structures, which adds further evidence to a possibly central mechanism of action of ASA. PMID:25201152
Lindén, C; Alm, A
2000-03-01
The purpose of this study was to measure if intraocular pressure (IOP) and IOP variations in patients with ocular hypertension and glaucoma are decreased by acetylsalicylic acid (ASA). The hypothesis to be tested was that short-term fluctuations in the IOP are caused by breaks of the inner wall of Schlemm's canal that are repaired by platelets inducing a cycle of breaks and repair. Furthermore, prostaglandins affect uveoscleral outflow and ASA inhibits prostaglandin biosynthesis and platelet aggregation. This implies that ASA may have complex effects on the IOP and its variations.In 28 patients with ocular hypertension or glaucoma the IOP was measured seven times during 2 hr on two succeeding days. Five hundred mg ASA or placebo was administrated orally in a masked fashion 15 hr prior to the second session. After wash-out, this procedure was repeated with a cross-over design. The same study outline was used in 28 glaucoma patients except for the cross-over design. There were no statistically significant differences in the mean IOP or in the IOP variations between the placebo treated and the ASA treated eyes in either group, and there were no significant differences between the day before and after treatment in any group. The results suggest that ASA does not affect IOP variations in a clinically significant way and that a single dose of ASA has no significant effect on mean IOP. Copyright 2000 Academic Press.
Reliability of equivalent sphere model in blood-forming organ dose estimation
NASA Technical Reports Server (NTRS)
Shinn, Judy L.; Wilson, John W.; Nealy, John E.
1990-01-01
The radiation dose equivalents to blood-forming organs (BFO's) of the astronauts at the Martian surface due to major solar flare events are calculated using the detailed body geometry of Langley and Billings. The solar flare spectra of February 1956, November 1960, and August 1972 events are employed instead of the idealized Webber form. The detailed geometry results are compared with those based on the 5-cm sphere model which was used often in the past to approximate BFO dose or dose equivalent. Larger discrepancies are found for the later two events possibly due to the lower numbers of highly penetrating protons. It is concluded that the 5-cm sphere model is not suitable for quantitative use in connection with future NASA deep-space, long-duration mission shield design studies.
ASAS-SN Discovery of a Possible Galactic Nova ASASSN-18ix
NASA Astrophysics Data System (ADS)
Stanek, K. Z.; Kochanek, C. S.; Shields, J. V.; Thompson, T. A.; Chomiuk, L.; Strader, J.; Shappee, B. J.; Holoien, T. W.-S.; Prieto, J. L.; Dong, Subo; Stritzinger, M.
2018-04-01
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014), using data from multiple ASAS-SN telescopes, we detect a new bright transient source, possibly a classical nova, but it might also be a young, large amplitude outburst of a cataclysmic variable Object RA (J2000) DEC (J2000) Gal l (deg) Gal b (deg) Disc.
Kenna, George A.; Zywiak, William H.; Swift, Robert M.; McGeary, John E.; Clifford, James S.; Shoaff, Jessica R.; Vuittonet, Cynthia; Fricchione, Samuel; Brickley, Michael; Beaucage, Kayla; Haass-Koffler, Carolina L.; Leggio, Lorenzo
2014-01-01
Background One hypothesis suggests that the differential response to ondansetron and serotonin specific re-uptake inhibitors (SSRIs) may be due to a functional polymorphism of the 5′-HTTLPR promoter region in SLC6A4, the gene that codes for the serotonin transporter (5-HTT). The LL 5′-HTTLPR genotype is postulated to be specifically sensitive to the effects of ondansetron with SS/SL 5′-HTTLPR genotypes sensitive to SSRIs. This study tests this hypothesis by matching non-treatment seeking alcohol dependent (AD) individuals with LL genotype to ondansetron and SS/SL genotypes to the SSRI sertraline, and mis-matching them assessing naturalistic and bar-laboratory alcohol drinking. Methods Seventy-seven AD individuals were randomized to one of two counterbalanced arms to receive sertraline 200mg/day or ondansetron 0.5 mg/day for three weeks followed by an alcohol self-administration experiment (ASAE), then received placebo for three weeks followed by a second ASAE. Individuals then received the alternate drug for three weeks followed by a third ASAE. Drinks per drinking day (DDD with drinks in SDUs) for 7 days prior to each ASAE and milliliters consumed during each ASAE were the primary outcomes. Results Fifty-five participants completed the study. The genotype x order interaction was significant [F(1,47) = 8.42, p = .006] for DDD. Three ANCOVAs were conducted for DDD during the week before each ASAE. Ondansetron compared to sertraline resulted in a significant reduction in DDD during the week before the first [F(1,47) = 7.64, p = .008] but not the third ASAE. There was no difference in milliliters consumed during each ASAE. Conclusion This study modestly supports the hypothesis that ondansetron may reduce DDD in AD individuals with the LL genotype as measured naturalistically. By contrast there was no support that ondansetron reduces drinking during the ASAEs or that sertraline reduces alcohol use in individuals who have SS/SL genotypes. We provide limited support that ondansetron may reduce drinking in non-treatment seeking individuals with the LL genotype. PMID:24773166
Böhm, Stephan Karl; Kruis, Wolfgang
2014-01-01
In 1977, 5-aminosalicylic acid (5-ASA) was discovered as a therapeutically active moiety of sulfasalazine (SASP) and was launched for topical and oral therapy of ulcerative colitis (UC) in 1984. As a first-step, delivery systems had to be developed to protect 5-ASA against absorption in the upper gastrointestinal tract, resulting in different and competing strategies (azo compounds, controlled release, and pH-dependent release). In a second step, at the beginning of the new century, coinciding with the expiration of patent protection for the first 5-ASA formulations, two component composite release mechanisms (pH-dependent and controlled release) were developed. Furthermore, the drug was formulated as granules instead of tablets, allowing higher unit strengths compared with tablets. Neither Salofalk Granu-Stix®, nor MMX 5-ASA, nor Pentasa® granules have initially been developed for once-daily (OD) dosing. A review of the achievements of 20 years of 5-ASA development has demonstrated that 5-ASA has equal efficacy compared with SASP at best, that there are no measurable differences in efficacy between various 5-ASA preparations, and that in a group of patients tolerating SASP, adverse event profiles of SASP and 5-ASA did not differ significantly, with SASP being the far cheaper substance. Therefore, drug adherence came into focus as a new goal for improving UC therapy. Although adherence is a complex and multifactorial construct, a simple dosing schedule may contribute to higher drug adherence and better efficacy of treatment. Simultaneously, the US 5-ASA market, estimated to be worth US$1.4 billion, is expected to grow continuously. Naturally, this very competitive market is not only driven by scientific progress but also by commercial interests. Thus, patents for minor changes to the formulation may serve as protection against drug companies trying to launch generic versions. Randomized controlled trials performed on OD dosing in induction of remission have demonstrated that OD administration of 5-ASA is as effective as conventional dosing in mild to moderate active UC. The three 5-ASA products MMX, Salofalk®, and Pentasa® employed in those studies so far have not shown differences in efficacy between OD and conventional dosing. No differences regarding safety outcomes have been detected between OD and conventional dosing, including incidence of adverse events, serious adverse events, or withdrawal from treatment due to an adverse event. Although the majority of patients prefer OD dosing to conventional dosing, it was not possible to detect differences in adherence between OD and multiple dose regimens in the clinical trial setting. Well-designed and controlled large-scale community-based studies are necessary to further investigate and prove the point of improved long-term adherence and treatment efficacy in OD dosing. PMID:25285021
NASA Technical Reports Server (NTRS)
Smith, Jeremy C.; Neitzke, Kurt W.; Bussink, Frank J. L.
2008-01-01
This paper presents the results from a study that investigates the performance of aspects of an Airborne Separation Assistance System (ASAS) under varying demand levels using realistic traffic patterns. This study only addresses the tactical aspects of an ASAS using aircraft state data (latitude, longitude, altitude, heading and speed) to detect and resolve projected conflicts. The main focus of this paper is to determine the extent to which sole reliance on the proposed tactical ASAS can maintain aircraft separation at demand levels up to three times current traffic. The effect of mixing ASAS equipped aircraft with non-equipped aircraft that do not have the capability to self-separate is also investigated.
Rectal 5-aminosalicylic acid for induction of remission in ulcerative colitis.
Marshall, John K; Thabane, Marroon; Steinhart, A Hillary; Newman, Jamie R; Anand, Anju; Irvine, E Jan
2010-01-20
5-Aminosalicylates (5-ASA) are considered a first-line therapy for inducing and maintaining remission of mild to moderately active ulcerative colitis (UC). When inflammation in UC is limited to the distal colon, 5-ASA can also be administered rectally as a suppository, enema or foam. A systematic review was undertaken to evaluate the efficacy of rectal 5-ASA for treating active distal UC. Electronic searches of the MEDLINE database (1966-2008), the Cochrane Central Register of Controlled Trials and the Cochrane IBD/FBD Group Specialized Trials Register were supplemented by manual reviews of reference listings and conference proceedings. Randomized trials comparing rectal 5-ASA to placebo or another active therapy were eligible for inclusion. Eligible trials enrolled patients with a distal disease margin less than 60 cm from the anal verge or distal to the splenic flexure. Trials that enrolled subjects less than 12 years of age were excluded. Eligibility was assessed by three authors. Data were extracted by two authors using standardized forms. Pooled odds ratios (POR) for inducing improvement and remission by symptomatic, endoscopic and histologic criteria were calculated using an intention to treat principle. Fixed effects models were used unless heterogeneity was encountered within groups (P < 0.10), where random effects models were used. All statistical analyses were performed using RevMan 5. Where sufficient data were available, subgroup analyses were performed for disease extent, total daily 5-ASA dose, 5-ASA formulation (enema,suppository, foam) and the type of control intervention (placebo or another active therapy). Thirty-eight studies fulfilled the inclusion criteria. Rectal 5-ASA was superior to placebo for inducing symptomatic, endoscopic and histological improvement and remission, with POR for symptomatic improvement 8.87 (8 trials, 95% CI: 5.30 to 14.83; P < 0.00001), endoscopic improvement 11.18 (5 trials, 95% CI 5.99 to 20.88; P < 0.00001), histologic improvement 7.69 (6 trials, 95% CI 3.26 to 18.12; P < 0.00001), symptomatic remission 8.30 (8 trials, 95% CI 4.28 to 16.12; P < 0.00001), endoscopic remission 5.31 (7 trials, 95% CI 3.15 to 8.92; P < 0.00001), and histologic remission 6.28 (5 trials, 95% CI 2.74 to 14.40; P < 0.0001). Rectal 5-ASA was superior to rectal corticosteroids for inducing symptomatic improvement and remission with POR 1.56 (6 trials, 95% CI 1.15 to 2.11; P = 0.004) and 1.65 (6 trials, 95% CI 1.11 to 2.45; P = 0.01), respectively. Rectal 5-ASA was not superior to oral 5-ASA for symptomatic improvement (POR 2.25; 95% CI 0.53 to 19.54; P = 0.27). Neither total daily dose nor 5-ASA formulation affected treatment response. Rectal 5-ASA should be considered a first-line therapy for patients with mild to moderately active distal UC. The optimal total daily dose and dose frequency of 5-ASA remain to be determined. Future research should define differences in efficacy among patient subgroups defined by proximal disease margin and disease activity. There is a strong need for consensus standardization of outcome measurements for clinical trials in ulcerative colitis.
NASA Astrophysics Data System (ADS)
Izsák, Róbert; Neese, Frank
2013-07-01
The 'chain of spheres' approximation, developed earlier for the efficient evaluation of the self-consistent field exchange term, is introduced here into the evaluation of the external exchange term of higher order correlation methods. Its performance is studied in the specific case of the spin-component-scaled third-order Møller--Plesset perturbation (SCS-MP3) theory. The results indicate that the approximation performs excellently in terms of both computer time and achievable accuracy. Significant speedups over a conventional method are obtained for larger systems and basis sets. Owing to this development, SCS-MP3 calculations on molecules of the size of penicillin (42 atoms) with a polarised triple-zeta basis set can be performed in ∼3 hours using 16 cores of an Intel Xeon E7-8837 processor with a 2.67 GHz clock speed, which represents a speedup by a factor of 8-9 compared to the previously most efficient algorithm. Thus, the increased accuracy offered by SCS-MP3 can now be explored for at least medium-sized molecules.
Interaction of Aspirin (Acetylsalicylic Acid) with Lipid Membranes
Barrett, Matthew A.; Zheng, Songbo; Roshankar, Golnaz; Alsop, Richard J.; Belanger, Randy K. R.; Huynh, Chris; Kučerka, Norbert; Rheinstädter, Maikel C.
2012-01-01
We studied the interaction of Aspirin (acetylsalicylic acid) with lipid membranes using x-ray diffraction for bilayers containing up to 50 mol% of aspirin. From 2D x-ray intensity maps that cover large areas of reciprocal space we determined the position of the ASA molecules in the phospholipid bilayers and the molecular arrangement of the molecules in the plane of the membranes. We present direct experimental evidence that ASA molecules participate in saturated lipid bilayers of DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) and preferably reside in the head group region of the membrane. Up to 50 mol% ASA molecules can be dissolved in this type of bilayer before the lateral membrane organization is disturbed and the membranes are found to form an ordered, 2D crystal-like structure. Furthermore, ASA and cholesterol were found to co-exist in saturated lipid bilayers, with the ASA molecules residing in the head group region and the cholesterol molecules participating in the hydrophobic membrane core. PMID:22529913
Modulation of mitomycin C-induced genotoxicity by acetyl- and thio- analogues of salicylic acid.
Pawar, Amol Ashok; Vikram, Ajit; Tripathi, Durga Nand; Padmanabhan, Shweta; Ramarao, Poduri; Jena, Gopabandhu
2009-01-01
Recent reports regarding acetylsalicylic acid (ASA) and its metabolites suggest suppressive effects against mitomycin C (MMC)-induced genotoxicity in a mice chromosomal aberration assay. Keeping this in mind, the potential anti-genotoxic effect of the thio-analogue of salicylic acid namely thio-salicylic acid (TSA) was speculated upon. The present study investigated and compared the anti-genotoxic potential of ASA and TSA. The study was performed in male swiss mice (20+/-2 g) using single-cell gel electrophoresis and a peripheral blood micronucleus assay. ASA and TSA (5, 10 or 20 mg/kg) were administered 15 minutes after MMC (1 mg/kg) once daily for 3 or 7 days. Both ASA and TSA significantly decreased the DNA damage induced by MMC as indicated by a decrease in the comet parameters in bone marrow cells and decreased frequencies of micronucleated reticulocytes in peripheral blood. The results clearly demonstrate the anti-genotoxic potential of ASA and TSA.
Shahabadi, Nahid; Fili, Soraya Moradi
2014-01-24
The interaction of mesalamine (5-aminosalicylic acid (5-ASA)) with bovine serum albumin (BSA) was investigated by fluorescence quenching, absorption spectroscopy, circular dichroism (CD) techniques, and molecular docking. Thermodynamic parameters (ΔH<0 and ΔS 0) indicated that the hydrogen bond and electrostatic forces played the major role in the binding of 5-ASA to BSA. The results of CD and UV-vis spectroscopy showed that the binding of this drug to BSA induces some conformational changes in BSA. Displacement experiments predicted that the binding of 5-ASA to BSA is located within domain III, Sudlows site 2, that these observations were substantiated by molecular docking studies. In addition, the docking result shows that the 5-ASA in its anionic form mainly interacts with Gln-416 residue through one hydrogen bond between H atom of 5-ASA anion and the adjacent O atom of the hydroxyl group of Gln-416. Copyright © 2013 Elsevier B.V. All rights reserved.
Yu, Ai-Nong; Zhou, Yong-Yan; Yang, Yi-Ni
2017-04-15
The kinetics of browning and the correlation between browning products (BPs) and pyrazine compounds were investigated by heating equimolar l-ascorbic acid (ASA)/acidic amino acids under weak alkaline conditions at 120-150°C for 10-120min. The formations of BPs and pyrazine compounds from the reaction were monitored by UV-vis and SPME-GC-FID, respectively. The formation of BPs in both ASA/l-glutamic acid and ASA/l-aspartic acid model reaction systems followed zero order reaction kinetics with activation energies (E a ) of 90.13 and 93.38kJ/mol, respectively. ASA/l-aspartic acid browned at a slightly higher rate than ASA/l-glutamic acid. The total concentration of pyrazine compounds was highly and positively correlated with that of BPs. Based on the observed kinetic data, the formation mechanisms of BPs and pyrazine compounds were proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.
Can 5-aminosalicylic acid suppository decrease the pain after rectal band ligation?
Kayhan, Burcak; Ozer, Digdem; Akdogan, Meral; Ozaslan, Ersan; Yuksel, Osman
2008-06-14
To investigate the effect of 5-aminosalicylic acid (5-ASA) suppositories on rectal band ligation-induced pain. Sixty patients were randomized into two treatment groups. Our results showed that there was no difference between 5-ASA suppository group and the control group for pain control. 5-ASA may be an alternative treatment for hemorrhoids; however, it does not affect the rectal band ligation-induced pain.
Temporal Aspects of the Action of ASA404 (Vadimezan; DMXAA)
Baguley, Bruce C; Siemann, Dietmar W
2013-01-01
ASA404, a flavonoid tumor-vascular disrupting agent (Tumor-VDA), is in clinical trial for the treatment of non-small cell lung cancer. Its action differs from both that of the tubulin binding class of Tumor-VDAs and antiangiogenic agents. In mice, ASA404 induces a sequence of changes in tumor tissue, starting within one hour with increased vascular permeability, increased endothelial apoptosis and decreased blood flow. Later effects include the release of serotonin, induction of tumor necrosis factor and other cytokines and chemokines, as well as induction of nitric oxide. This cascade of events induces sustained effects on blood flow, tumor hypoxia, vascular failure, inflammatory responses and, in some tumors, complete regression. One feature of the action of ASA404 against murine tumors is its ability to potentiate the effects of radiation and a variety of chemotherapeutic agents. The flavonoid class appears to be unique because of its dual action on vascular endothelial function and innate immunity. The translation of preclinical to clinical results demands an understanding of both the mechanisms underlying the dual effects and the species differences in ASA404 activity. Clinical trials indicate that the future of ASA404 as an effective agent relies on a deep appreciation of its cellular action. PMID:20964495
Moon, Hyung-Geun; Kang, Chil Sung; Choi, Jun-Pyo; Choi, Dong Sic; Choi, Hyun Il; Choi, Yong Wook; Jeon, Seong Gyu; Yoo, Joo-Yeon; Jang, Myoung Ho; Gho, Yong Song; Kim, Yoon-Keun
2013-01-01
T-helper (Th)17 cell responses are important for the development of neutrophilic inflammatory disease. Recently, we found that acetyl salicylic acid (ASA) inhibited Th17 airway inflammation in an asthma mouse model induced by sensitization with lipopolysaccharide (LPS)-containing allergens. To investigate the mechanism(s) of the inhibitory effect of ASA on the development of Th17 airway inflammation, a neutrophilic asthma mouse model was generated by intranasal sensitization with LPS plus ovalbumin (OVA) and then challenged with OVA alone. Immunologic parameters and airway inflammation were evaluated 6 and 48 h after the last OVA challenge. ASA inhibited the production of interleukin (IL)-17 from lung T cells as well as in vitro Th17 polarization induced by IL-6. Additionally, ASA, but not salicylic acid, suppressed Th17 airway inflammation, which was associated with decreased expression of acetyl-STAT3 (downstream signaling of IL-6) in the lung. Moreover, the production of IL-6 from inflammatory cells, induced by IL-17, was abolished by treatment with ASA, whereas that induced by LPS was not. Altogether, ASA, likely via its acetyl moiety, inhibits Th17 airway inflammation by blockade of IL-6 and IL-17 positive feedback. PMID:23306703
Larkin, J O; Bourke, M G; Muhammed, A; Waldron, R; Barry, K; Eustace, P W
2010-12-01
Most patients presenting with acutely perforated duodenal ulcer undergo operation, but conservative treatment may be indicated when an ulcer has spontaneously sealed with minimal/localised peritoneal irritation or when the patient's premorbid performance status is poor. We retrospectively reviewed our experience with operative and conservative management of perforated duodenal ulcers over a 10-year period and analysed outcome according to American Society of Anesthesiologists (ASA) score. The records of all patients presenting with perforated duodenal ulcer to the Department of Surgery, Mayo General Hospital, between January 1998 and December 2007 were reviewed. Age, gender, co-morbidity, ASA-score, clinical presentation, mode of management, operative procedures, morbidity and mortality were considered. Of 76 patients included, 48 (44 operative, 4 conservative) were ASA I-III, with no mortality irrespective of treatment. Amongst 28 patients with ASA-score IV/V, mortality was 54.5% (6/11) following operative management and 52.9% (9/17) with conservative management. In patients with a perforated duodenal ulcer and ASA-score I-III, postoperative outcome is uniformly favourable. We recommend these patients have repair with peritoneal lavage performed, routinely followed postoperatively by empirical triple therapy. Given that mortality is equivalent between ASA IV/V patients whether managed operatively or conservatively, we suggest that both management options are equally justifiable.
Mediators of the Relationship Between Sexual Assault and Sexual Behaviors in College Women.
Kelley, Erika L; Gidycz, Christine A
2017-07-01
Some research shows that sexual assault victimization is associated with increased engagement in risky sexual behavior (e.g., intercourse without use of a condom or contraceptives), whereas other research indicates sexual assault victimization is related to sexual aversion. The purpose of the current study was to examine whether posttraumatic stress symptoms, alcohol use, and sexual assertiveness mediated the relationship between adolescent/emerging adulthood sexual assault (ASA) and risky sexual behavior, and whether posttraumatic stress symptoms mediated the relationship between ASA and sexual aversion, among college women. A sample of 462 women from a Midwestern university completed online questionnaires assessing ASA, child sexual abuse (CSA), posttraumatic stress symptoms (i.e., intrusion, avoidance, hyperarousal, and dissociation), alcohol use, sexual assertiveness, risky sexual behavior, and sexual aversion. CSA was considered as a covariate in the mediation models. Results of mediation analyses showed that the relationship between ASA and risky sexual behavior with a new partner was partially mediated by greater alcohol use and lower sexual assertiveness and that the relationship between ASA and risky sexual behavior with a regular partner was partially mediated by greater alcohol use. Results of a model examining mediators of ASA and sexual aversion detected no significant mediators. Results suggest that college women with a history of ASA would benefit from psychoeducation on the effect of alcohol on sexual decision-making, as well as from sexual assertiveness skills training, to reduce potential risks associated with risky sexual behaviors, particularly with lesser known partners, including sexually transmitted infections and sexual revictimization.
3D Space Radiation Transport in a Shielded ICRU Tissue Sphere
NASA Technical Reports Server (NTRS)
Wilson, John W.; Slaba, Tony C.; Badavi, Francis F.; Reddell, Brandon D.; Bahadori, Amir A.
2014-01-01
A computationally efficient 3DHZETRN code capable of simulating High Charge (Z) and Energy (HZE) and light ions (including neutrons) under space-like boundary conditions with enhanced neutron and light ion propagation was recently developed for a simple homogeneous shield object. Monte Carlo benchmarks were used to verify the methodology in slab and spherical geometry, and the 3D corrections were shown to provide significant improvement over the straight-ahead approximation in some cases. In the present report, the new algorithms with well-defined convergence criteria are extended to inhomogeneous media within a shielded tissue slab and a shielded tissue sphere and tested against Monte Carlo simulation to verify the solution methods. The 3D corrections are again found to more accurately describe the neutron and light ion fluence spectra as compared to the straight-ahead approximation. These computationally efficient methods provide a basis for software capable of space shield analysis and optimization.
Wind Tunnel Investigation of a Balloon as Decelerator at Mach Numbers from 1.47 to 2.50
NASA Technical Reports Server (NTRS)
McShera, John T.; Keyes, J. Wayne
1961-01-01
A wind-tunnel investigation was conducted to study the characteristics of a towed spherical balloon as a drag device at Mach numbers from 1.47 to 2.50, Reynolds numbers from 0.36 x 10(exp 6) to 1.0 x 10(exp 6) , and angles of attack from -15 to 15 degrees. Tow-cable length was approximately 24 inches from asymmetric body to cone on the upstream side of the balloon. As the tow cable was lengthened the balloon reached a point in the test section where wall-reflected shocks intersected the balloon and caused severe oscillations. As a result, the tow cable broke and the inflatable balloon model was destroyed. Further tests used a model rigid plastic sphere 6.75 inches in diameter. Tow cable length was approximately 24 inches from asymmetric body to the upstream side of the sphere.
Acoustical radiation torque and force for spheres and Bessel beam extinction efficiency
NASA Astrophysics Data System (ADS)
Marston, Philip L.; Zhang, Likun
2014-11-01
The scattering of optical and acoustical beams is relevant to the levitation and manipulation of drops. Here we examine theoretical developments in the acoustical case. We previously showed how the optical theorem for extinction can be extended to invariant beams. The example of a sphere in a Bessel beam facilitates the direct comparison with a circular disc computed using Babinet's principle and the Kirchhoff approximation. In related work, by considering traveling or standing wave first-order vortex beams we previously showed that the radiation torque is the ratio of the absorbed power and the radian acoustic frequency. By modifying the scattering to account for the viscosity of the surrounding fluid in the analysis of the absorbed power, approximations for radiation torque and force are obtained at long wavelengths in special cases and these can be compared with results published elsewhere.
Snijder, Roel J R; Luermans, Justin G L M; de Heij, Albert H; Thijs, Vincent; Schonewille, Wouter J; Van De Bruaene, Alexander; Swaans, Martin J; Budts, Werner I H L; Post, Martijn C
2016-12-01
A patent foramen ovale (PFO) with atrial septal aneurysm (ASA) has been identified as a risk factor for cryptogenic stroke. Patients with migraine with aura (MA) appear to be at risk for silent brain infarction, which might be related to the presence of a PFO. However, the association between MA and PFO with ASA has never been reported. We examined this association in a large observational study. Patients (>18 years) who underwent an agitated saline transesophageal echocardiography (cTEE) at our outpatient clinics within a timeframe of 4 years were eligible to be included. Before cTEE they received a validated headache questionnaire. Two neurologists diagnosed migraine with or without aura according to the International Headache Criteria. A total of 889 patients (mean age 56.4±14.3 years, 41.7% women) were included. A PFO was present in 23.2%, an isolated ASA in 2.7%, and a PFO with ASA in 6.9%. The occurrence of migraine was 18.9%; the occurrence of MA was 8.1%. The prevalence of PFO with ASA was significantly higher in patients with MA compared to patients without migraine (18.1% vs 6.1%; OR 3.72, 95% CI 1.86-7.44, P<0.001). However, a PFO without ASA was not significantly associated with MA (OR 1.50, 95% CI 0.79-2.82, P=0.21). Interestingly, a PFO with ASA was strongly associated with MA (OR 2.71, 95% CI 1.23-5.95, P=0.01). In this large observational study, PFO with ASA was significantly associated with MA only. PFO closure studies should focus on this specific intra-atrial anomaly. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
2014-01-01
Background Binding free energy and binding hot spots at protein-protein interfaces are two important research areas for understanding protein interactions. Computational methods have been developed previously for accurate prediction of binding free energy change upon mutation for interfacial residues. However, a large number of interrupted and unimportant atomic contacts are used in the training phase which caused accuracy loss. Results This work proposes a new method, βACV ASA , to predict the change of binding free energy after alanine mutations. βACV ASA integrates accessible surface area (ASA) and our newly defined β contacts together into an atomic contact vector (ACV). A β contact between two atoms is a direct contact without being interrupted by any other atom between them. A β contact’s potential contribution to protein binding is also supposed to be inversely proportional to its ASA to follow the water exclusion hypothesis of binding hot spots. Tested on a dataset of 396 alanine mutations, our method is found to be superior in classification performance to many other methods, including Robetta, FoldX, HotPOINT, an ACV method of β contacts without ASA integration, and ACV ASA methods (similar to βACV ASA but based on distance-cutoff contacts). Based on our data analysis and results, we can draw conclusions that: (i) our method is powerful in the prediction of binding free energy change after alanine mutation; (ii) β contacts are better than distance-cutoff contacts for modeling the well-organized protein-binding interfaces; (iii) β contacts usually are only a small fraction number of the distance-based contacts; and (iv) water exclusion is a necessary condition for a residue to become a binding hot spot. Conclusions βACV ASA is designed using the advantages of both β contacts and water exclusion. It is an excellent tool to predict binding free energy changes and binding hot spots after alanine mutation. PMID:24568581
Garraway, Isla P; Sun, Wenyi; Tran, Chau P; Perner, Sven; Zhang, Bao; Goldstein, Andrew S; Hahm, Scott A; Haider, Maahum; Head, Christian S; Reiter, Robert E; Rubin, Mark A; Witte, Owen N
2010-01-01
BACKGROUND Prostate stem/progenitor cells function in glandular development and maintenance. They may be targets for tumor initiation, so characterization of these cells may have therapeutic implications. Cells from dissociated tissues that form spheres in vitro often represent stem/progenitor cells. A subset of human prostate cells that form prostaspheres were evaluated for self-renewal and tissue regeneration capability in the present study. METHODS Prostaspheres were generated from 59 prostatectomy specimens. Lineage marker expression and TMPRSS-ERG status was determined via immunohistochemistry and fluorescence in situ hybridization (FISH). Subpopulations of prostate epithelial cells were isolated by cell sorting and interrogated for sphere-forming activity. Tissue regeneration potential was assessed by combining sphere-forming cells with rat urogenital sinus mesenchyme (rUGSM) subcutaneously in immunocompromised mice. RESULTS Prostate tissue specimens were heterogeneous, containing both benign and malignant (Gleason 3–5) glands. TMPRSS-ERG fusion was found in approximately 70% of cancers examined. Prostaspheres developed from single cells at a variable rate (0.5–4%) and could be serially passaged. A basal phenotype (CD44+CD49f+CK5+p63+CK8−AR−PSA−) was observed among sphere-forming cells. Subpopulations of prostate cells expressing tumor-associated calcium signal transducer 2 (Trop2), CD44, and CD49f preferentially formed spheres. In vivo implantation of sphere-forming cells and rUGSM regenerated tubular structures containing discreet basal and luminal layers. The TMPRSS-ERG fusion was absent in prostaspheres derived from fusion-positive tumor tissue, suggesting a survival/growth advantage of benign prostate epithelial cells. CONCLUSION Human prostate sphere-forming cells self-renew, have tissue regeneration capability, and represent a subpopulation of basal cells. Prostate 70: 491–501, 2010. © 2009 Wiley-Liss, Inc. PMID:19938015
Hyperspectral data analysis for estimation of foliar biochemical content along the Oregon transect
NASA Technical Reports Server (NTRS)
Johnson, Lee F.; Peterson, David L.
1991-01-01
The NASA Oregon Transect Ecosystem Research (OTTER) project completed a data acquisition phase. Data were acquired with several airborne imaging spectrometers. Included were the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) aboard the ER-2, the Advanced Solidstate Array Spectrometer (ASAS) aboard the C-130, and the Fluorescence Line Imager (FLI) and Compact Airborne Spectrographic Imager (CASI), both aboard light aircraft. In addition, Spectron visible and near-infrared data were acquired in transects across study areas from a low-altitude ultralight craft. Sunphotometer data were taken approximately coincident with each overflight for atmospheric correction of the aircraft data.
Erratum: A Comparison of Closures for Stochastic Advection-Diffusion Equations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jarman, Kenneth D.; Tartakovsky, Alexandre M.
2015-01-01
This note corrects an error in the authors' article [SIAM/ASA J. Uncertain. Quantif., 1 (2013), pp. 319 347] in which the cited work [Neuman, Water Resour. Res., 29(3) (1993), pp. 633 645] was incorrectly represented and attributed. Concentration covariance equations presented in our article as new were in fact previously derived in the latter work. In the original abstract, the phrase " . . .we propose a closed-form approximation to two-point covariance as a measure of uncertainty. . ." should be replaced by the phrase " . . .we study a closed-form approximation to two-point covariance, previously derived in [Neumanmore » 1993], as a measure of uncertainty." The primary results in our article--the analytical and numerical comparison of existing closure methods for specific example problems are not changed by this correction.« less
Solutions for the conductivity of multi-coated spheres and spherically symmetric inclusion problems
NASA Astrophysics Data System (ADS)
Pham, Duc Chinh
2018-02-01
Variational results on the macroscopic conductivity (thermal, electrical, etc.) of the multi-coated sphere assemblage have been used to derive the explicit expression of the respective field (thermal, electrical, etc.) within the spheres in d dimensions (d=2,3). A differential substitution approach has been developed to construct various explicit expressions or determining equations for the effective spherically symmetric inclusion problems, which include those with radially variable conductivity, different radially variable transverse and normal conductivities, and those involving imperfect interfaces, in d dimensions. When the volume proportion of the outermost spherical shell increases toward 1, one obtains the respective exact results for the most important specific cases: the dilute solutions for the compound inhomogeneities suspended in a major matrix phase. Those dilute solution results are also needed for other effective medium approximation schemes.
Contact area of rough spheres: Large scale simulations and simple scaling laws
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pastewka, Lars, E-mail: lars.pastewka@kit.edu; Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218; Robbins, Mark O., E-mail: mr@pha.jhu.edu
2016-05-30
We use molecular simulations to study the nonadhesive and adhesive atomic-scale contact of rough spheres with radii ranging from nanometers to micrometers over more than ten orders of magnitude in applied normal load. At the lowest loads, the interfacial mechanics is governed by the contact mechanics of the first asperity that touches. The dependence of contact area on normal force becomes linear at intermediate loads and crosses over to Hertzian at the largest loads. By combining theories for the limiting cases of nominally flat rough surfaces and smooth spheres, we provide parameter-free analytical expressions for contact area over the wholemore » range of loads. Our results establish a range of validity for common approximations that neglect curvature or roughness in modeling objects on scales from atomic force microscope tips to ball bearings.« less
NASA Astrophysics Data System (ADS)
Hodgkinson, J.; Masiyano, D.; Tatam, R. P.
2013-02-01
We have studied the effect on 2nd harmonic wavelength modulation spectroscopy of the use of integrating spheres as multipass gas cells. The gas lineshape becomes distorted at high concentrations, as a consequence of the exponential pathlength distribution of the sphere, introducing nonlinearity beyond that expected from the Beer-Lambert law. We have modelled this numerically for methane absorption at 1.651 μm, with gas concentrations in the range of 0-2.5 %vol in air. The results of this model compare well with experimental measurements. The nonlinearity for the 2 fWMS measurements is larger than that for direct scan measurements; if this additional effect were not accounted for, the resulting error would be approximately 20 % of the reading at a concentration of 2.5 %vol methane.
Market Survey and Analysis in Support of ASAS Computer-Based Training System Design
1988-11-01
development nf a recommended strategy for incorporating CBT in the ASAS/ENSCE training system. Approach - In order to establish the state of the art and...a training system which will meet ASAS training requirements. Eleven subsystems are described in terms of their functional input to the overall...keyboard and displays used in actual operation are also used in training, maximizing the transfer effect from practice situations to actual system
Boutin, Claude; Geindreau, Christian
2010-09-01
This paper presents a study of transport parameters (diffusion, dynamic permeability, thermal permeability, trapping constant) of porous media by combining the homogenization of periodic media (HPM) and the self-consistent scheme (SCM) based on a bicomposite spherical pattern. The link between the HPM and SCM approaches is first established by using a systematic argument independent of the problem under consideration. It is shown that the periodicity condition can be replaced by zero flux and energy through the whole surface of the representative elementary volume. Consequently the SCM solution can be considered as a geometrical approximation of the local problem derived through HPM for materials such that the morphology of the period is "close" to the SCM pattern. These results are then applied to derive the estimates of the effective diffusion, the dynamic permeability, the thermal permeability and the trapping constant of porous media. These SCM estimates are compared with numerical HPM results obtained on periodic arrays of spheres and polyhedrons. It is shown that SCM estimates provide good analytical approximations of the effective parameters for periodic packings of spheres at porosities larger than 0.6, while the agreement is excellent for periodic packings of polyhedrons in the whole range of porosity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joseph Berkmans, A.; Jagannatham, M.; Priyanka, S.
Highlights: • Polymer wastes are converted into ultrafine and nano carbon tubes and spheres. • Simple process with a minimal processing time. • It is a catalyst free and solvent free approach. • This process forms branched ultrafine carbon tubules with nano channels. - Abstract: Upcycling polymer wastes into useful, and valuable carbon based materials, is a challenging process. We report a novel catalyst-free and solvent-free technique for the formation of nano channeled ultrafine carbon tubes (NCUFCTs) and multiwalled carbon nanotubes (MWCNTs) from polyethylene terephthalate (PET) wastes, using rotating cathode arc discharge technique. The soot obtain from the anode containsmore » ultrafine and nano-sized solid carbon spheres (SCS) with a mean diameter of 221 nm and 100 nm, respectively, formed at the lower temperature region of the anode where the temperature is approximately 1700 °C. The carbon spheres are converted into long “Y” type branched and non-branched NCUFCTs and MWCNTs at higher temperature regions where the temperature is approximately 2600 °C, with mean diameters of 364 nm and 95 nm, respectively. Soot deposited on the cathode is composed of MWCNTs with a mean diameter of 20 nm and other nanoparticles. The tubular structures present in the anode are longer, bent and often coiled with lesser graphitization compared to the nanotubes in the soot on the cathode.« less
Irita, Kazuo; Kawashima, Yasuo; Tsuzaki, Koichi; Iwao, Yasuhide; Kobayashi, Tsutomu; Seo, Norimasa; Goto, Yasuyuki; Morita, Kiyoshi; Shiraishi, Yoshito; Nakao, Yasuo; Tanaka, Yoshifumi; Tosaki, Youko; Dohi, Shuji; Obara, Hidefumi
2002-01-01
Perioperative mortality and morbidity in Japan from Jan. 1 to Dec. 31, 2000 were studied retrospectively. Committee on Operating Room Safety in Japanese Society of Anesthesiologists (JSA) sent confidential questionnaires to 794 certified training hospitals of JSA and received answers from 67.6% of the hospitals. We analyzed their answers with a special reference to ASA physical status (ASA-PS). The total number of anesthesia available for this analysis was 897,733. The percentages of patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E are 38.0, 40.3, 8.5, 0.4, 4.3, 5.3, 2.5, and 0.7%, respectively. Mortality and morbidity from all kinds of causes including anesthetic management, intraoperative events, co-existing diseases, and surgical problems were as follows. The incidences of cardiac arrest (per 10,000 cases of anesthesia) were 1.11, 3.26, 12.25, 54.60, 0.77, 4.46, 21.08 and 217.75 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The incidences of critical events including cardiac arrest, severe hypotension, and severe hypoxemia were 6.89, 20.22, 62.18, 148.21, 6.71, 20.38, 106.72 and 592.21 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The mortality rates (death during anesthesia and within 7 postoperative days) after cardiac arrest were 0.26, 0.77, 3.69, 41.60, 0.00, 1.06, 9.42 and 163.31 per 10,000 cases of anesthesia in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The overall mortality rates were 0.32, 1.38, 9.75, 70.20, 0.26, 2.12, 29.15 and 353.02 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. Overall mortality and morbidity were higher in emergency anesthesia than in elective anesthesia. ASA-PS correlated well with overall mortality and morbidity, regardless of etiology. The incidences of cardiac arrest totally attributable to anesthesia were 0.23, 0.50, 1.32, 0.00, 0.00, 0.85, 2.69 and 4.95 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The incidences of all critical events totally attributable to anesthesia were 3.13, 5.56, 11.46, 5.20, 3.87, 5.94, 13.90 and 14.85 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The mortality rates after cardiac arrest totally attributable to anesthesia were 0.03, 0.03, 0.00, 0.00, 0.00, 0.21, 0.45 and 3.30 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The overall mortality rates totally attributable to anesthesia were 0.03, 0.06, 0.00, 0.00, 0.00, 0.21, 0.45 and 6.60 in patients with ASA-PS of I, II, III, IV, I E, II E, III E, and IV E, respectively. The overall mortality rate totally attributable to anesthesia among patients with good physical status (ASA-PS of I, II, I E, II E) was 0.05. Anesthetic management was mainly responsible for critical events in patients with good physical status, while coexisting diseases were in those with poor physical status. Surgical problems including procedures and massive hemorrhage were the leading causes of mortality in patients with good physical status. We reconfirmed that ASA-PS is useful to predict perioperative mortality and morbidity. It also seems likely that we should make much more efforts to reduce anesthetic morbidity in patients with good physical status, and to improve preanesthetic assessment and preparation in those with poor physical status. Reducing mortality and morbidity from surgical problems is also required for improving perioperative mortality.
Krüger, Jan-Christopher; Meves, Saskia H; Kara, Kaffer; Mügge, Andreas; Neubauer, Horst
2014-10-01
Several platelet function test systems exist for the evaluation of the platelet inhibitory effect in patients on P2Y12 inhibitors and/or acetylsalicylic acid (ASA, aspirin) therapy. Studies comparing different available assays found only a poor correlation. The objective of the present study was to evaluate the correlation and agreement between single electrode (SEA) and multiple electrode (MEA) aggregometry. In whole blood arachidonic acid (AA) and adenosine diphosphate (ADP)-induced platelet aggregation was measured simultaneously using SEA (Chrono-Log) and MEA (Multiplate). We analyzed a total of 226 measurements taken from 58 patients on single ASA therapy or dual antiplatelet therapy with ASA and a thienopyridine. A cut-off value for clopidogrel/prasugrel high on-treatment platelet reactivity (HPR) of > 47 units (U) was chosen for MEA testing using hirudin and > 5 Ohm for SEA with citrate anticoagulated blood samples. The respective cut-off values for ASA HPR were > 30 U for the MEA assay and > 1 Ohm for SEA testing. There was a good correlation of the prevalence of thienopyridine-HPR in both whole blood assays (Spearman rank correlation coefficient r = 0.698) and a good inter-rate accordance (Cohen's Kappa statistic κ = 0.648). For AA-induced aggregation, the correlation of the results obtained was significant (r = 0.536; p < 0.001) and detecting ASA-HPR revealed a moderate (κ = 0.482) correlation between both impedance aggregometry assays. Platelet function testing using SEA and MEA provided both good accordance and correlation and therefore study results obtained by these two assays similarly enabled the detection of HPR of thienopyridine (and ASA) therapy.
Takeuchi, Koji; Takayama, Shinichi; Hashimoto, Erika; Itayama, Misaki; Amagase, Kikuko; Izuhara, Chitose
2014-12-01
We examined the prophylactic effect of rebamipide on gastric bleeding induced by the perfusion of aspirin (acetylsalicylic acid [ASA]) plus clopidogrel under the stimulation of acid secretion in rats. Under urethane anesthesia, acid secretion was stimulated by the i.v. infusion of histamine (8 mg/kg/h), and the stomach was perfused with 25 mmol/L ASA at a rate of 0.4 mL/min. Gastric bleeding was evaluated as the concentration of hemoglobin in the perfusate. Clopidogrel (30 mg/kg) was given p.o. 24 h before the perfusion. Rebamipide (3-30 mg/kg) or other antiulcer drugs were given i.d. before the ASA perfusion. Slight gastric bleeding or damage was observed with the perfusion of ASA under the stimulation of acid secretion, whereas these responses were significantly increased in the presence of clopidogrel. Both omeprazole and famotidine inhibited acid secretion and prevented these responses to ASA plus clopidogrel. Rebamipide had no effect on acid secretion, but dose-dependently prevented gastric bleeding in response to ASA plus clopidogrel, with the degree of inhibition being almost equivalent to that of the antisecretory drugs, and the same effects were obtained with the gastroprotective drugs, irsogladine and teprenone. These agents also reduced the severity of gastric lesions, although the effects were less than those of the antisecretory drugs. These results suggest that the antiplatelet drug, clopidogrel, increases gastric bleeding induced by ASA under the stimulation of acid secretion, and the gastroprotective drug, rebamipide, is effective in preventing the gastric bleeding induced under such conditions, similar to antisecretory drugs. © 2014 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.
Piscitelli, Daniele; Falaki, Ali; Solnik, Stanislaw; Latash, Mark L.
2016-01-01
We explored two aspects of feed-forward postural control, anticipatory postural adjustments (APAs) and anticipatory synergy adjustments (ASAs) seen prior to self-triggered unloading with known and unknown direction of the perturbation. In particular, we tested two main hypotheses predicting contrasting changes in APAs and ASAs. The first hypothesis predicted no major changes in ASAs. The second hypothesis predicted delayed APAs with predominance of co-contraction patterns when perturbation direction was unknown. Healthy subjects stood on the force plate and help a bar with two loads acting in the forward and backward directions. They pressed a trigger that released one of the loads causing a postural perturbation. In different series, the direction of the perturbation was either known (the same load released in all trials) or unknown (the subjects did not know which of the two loads would be released). Surface electromyograms were recorded and used to quantify APAs, synergies stabilizing center of pressure coordinate (within the uncontrolled manifold hypothesis), and ASA. APAs and ASAs were seen in all conditions. APAs were delayed and predominance of co-contraction patterns was seen under the conditions with unpredictable direction of perturbation. In contrast, no significant changes in synergies and ASAs were seen. Overall, these results show that feed-forward control of vertical posture has two distinct components, reflected in APAs and ASAs, which show qualitatively different adjustments with changes in predictability of the direction of perturbation. These results are interpreted within the recently proposed hierarchical scheme of the synergic control of motor tasks. The observations underscore the complexity of the feed-forward postural control, which involves separate changes in salient performance variables (such as coordinate of the center of pressure) and in their stability properties. PMID:27866261
Piscitelli, Daniele; Falaki, Ali; Solnik, Stanislaw; Latash, Mark L
2017-03-01
We explored two aspects of feed-forward postural control, anticipatory postural adjustments (APAs) and anticipatory synergy adjustments (ASAs) seen prior to self-triggered unloading with known and unknown direction of the perturbation. In particular, we tested two main hypotheses predicting contrasting changes in APAs and ASAs. The first hypothesis predicted no major changes in ASAs. The second hypothesis predicted delayed APAs with predominance of co-contraction patterns when perturbation direction was unknown. Healthy subjects stood on the force plate and held a bar with two loads acting in the forward and backward directions. They pressed a trigger that released one of the loads causing a postural perturbation. In different series, the direction of the perturbation was either known (the same load released in all trials) or unknown (the subjects did not know which of the two loads would be released). Surface electromyograms were recorded and used to quantify APAs, synergies stabilizing center of pressure coordinate (within the uncontrolled manifold hypothesis), and ASA. APAs and ASAs were seen in all conditions. APAs were delayed, and predominance of co-contraction patterns was seen under the conditions with unpredictable direction of perturbation. In contrast, no significant changes in synergies and ASAs were seen. Overall, these results show that feed-forward control of vertical posture has two distinct components, reflected in APAs and ASAs, which show qualitatively different adjustments with changes in predictability of the direction of perturbation. These results are interpreted within the recently proposed hierarchical scheme of the synergic control of motor tasks. The observations underscore the complexity of the feed-forward postural control, which involves separate changes in salient performance variables (such as coordinate of the center of pressure) and in their stability properties.
Fasano, Serena; Pierro, Luciana; Pantano, Ilenia; Iudici, Michele; Valentini, Gabriele
2017-07-01
Systemic lupus erythematosus (SLE) is associated with an increased risk of cardiovascular disease (CVD). Thromboprophylaxis with low-dose aspirin (ASA) and hydroxychloroquine (HCQ) seems promising in SLE. We investigated the effects of HCQ cumulative dosages (c-HCQ) and the possible synergistic efficacy of ASA and HCQ in preventing a first CV event (CVE) in patients with SLE. Patients consecutively admitted to our center who, at admission, satisfied the 1997 American College of Rheumatology and/or 2012 Systemic Lupus Collaborating Clinics classification criteria for SLE, and had not experienced any CVE, were enrolled. The occurrence of a thrombotic event, use of ASA, and c-HCQ were recorded. Kaplan-Meier analysis was performed to determine the c-HCQ associated with a lower incidence of CVE. Cox regression analysis served to identify factors associated with a first CVE. For the study, 189 patients with SLE were enrolled and monitored for 13 years (median). Ten CVE occurred during followup. At Kaplan-Meier analysis, the CVE-free rate was higher in ASA-treated patients administered a c-HCQ > 600 g (standard HCQ dose for at least 5 yrs) than in patients receiving ASA alone, or with a c-HCQ dose < 600 g (log-rank test chi-square = 4.01, p = 0.04). Multivariate analysis showed that antimalarials plus ASA protected against thrombosis (HR 0.041 and HR 0.047, respectively), while antiphospholipid antibodies (HR 17.965) and hypertension (HR 18.054) increased the risk of a first CVE. Our results suggest that prolonged use of HCQ plus ASA is thromboprotective in SLE and provides additional evidence for its continued use in patients with SLE.
Platelet function in whole-blood donors is impaired: the effects of painkillers.
Curvers, Joyce; Dielis, Arne W J H; Heeremans, Judith; van Wersch, Jan W J
2007-01-01
Aspirin (ASA) or non-aspirin-like nonsteroidal anti-inflammatory drugs (NSAIDs) influence platelet (PLT) function by inhibiting cyclooxygenase enzymes. In this study, the aim was to address the use of ASA or NSAIDs before donation and the effect on PLT function. Donors were asked questions about recent use of ASA or NSAIDs. Furthermore, PLT function was evaluated by measurement of the closure time (CT) in a PLT function analyzer (PFA-100, Dade Behring) and by aggregometry (response to ADP or arachidonic acid [AA]). Of 100 questioned donors, 22 percent had used ASA (n = 4), NSAIDs (n = 6), or paracetamol (n = 12) before donation. Upon assessment of the PLT function in the PFA-100, 27 donors showed values of greater than 180 seconds, indicative of impaired PLT function. Of these, only 7 had used pain killers before donation. Furthermore, 15 of 22 users had normal CTs. Aggregation after stimulation with AA was absent in 33 PLT-rich samples. Again only 8 had reported use of ASA (3), NSAIDs (1), or paracetamol (4). Of the 22 users, 14 had normal AA aggregation responses. All donor samples showed ADP-induced aggregation, indicating PLT integrity. There was no difference between the group of donors who reported the intake of ASA or NSAIDs and the group of donors who did not with respect to the tested PLT function assays. It is concluded that there is a considerable group of donors that use PLT-influencing medication before donation. A relation between the reported use and impaired PLT function in blood donors could not be established, however. Impaired PLT function as tested may have other causes than intake of ASA or NSAIDs.
A mission-based productivity compensation model for an academic anesthesiology department.
Reich, David L; Galati, Maria; Krol, Marina; Bodian, Carol A; Kahn, Ronald A
2008-12-01
We replaced a nearly fixed-salary academic physician compensation model with a mission-based productivity model with the goal of improving attending anesthesiologist productivity. The base salary system was stratified according to rank and clinical experience. The supplemental pay structure was linked to electronic patient records and a scheduling database to award points for clinical activity; educational, research, and administrative points systems were constructed in parallel. We analyzed monthly American Society of Anesthesiologist (ASA) unit data for operating room activity and physician compensation from 2000 through mid-2007, excluding the 1-yr implementation period (July 2004-June 2005) for the new model. Comparing 2005-2006 with 2000-2004, quarterly ASA units increased by 14% (P = 0.0001) and quarterly ASA units per full-time equivalent increased by 31% (P < 0.0001), while quarterly ASA units per anesthetizing location decreased by 10% (P = 0.046). Compared with a baseline year (2001), Instructor and Assistant Professor faculty compensation increased more than Associate Professor and Professor faculty (P < 0.001) in both pre- and postimplementation periods. There were larger compensation increases for the postimplementation period compared with preimplementation across faculty rank groupings (P < 0.0001). Academic and educational output was stable. Implementing a productivity-based faculty compensation model in an academic department was associated with increased mean supplemental pay with relatively fewer faculty. ASA units per month and ASA units per operating room full-time equivalent increased, and these metrics are the most likely drivers of the increased compensation. This occurred despite a slight decrease in clinical productivity as measured by ASA units per anesthetizing location. Academic and educational output was stable.
Mellidou, Ifigeneia; Chagné, David; Laing, William A.; Keulemans, Johan; Davey, Mark W.
2012-01-01
To identify the genetic factors underlying the regulation of fruit vitamin C (l-ascorbic acid [AsA]) concentrations, quantitative trait loci (QTL) studies were carried out in an F1 progeny derived from a cross between the apple (Malus × domestica) cultivars Telamon and Braeburn over three years. QTL were identified for AsA, glutathione, total antioxidant activity in both flesh and skin tissues, and various quality traits, including flesh browning. Four regions on chromosomes 10, 11, 16, and 17 contained stable fruit AsA-QTL clusters. Mapping of AsA metabolic genes identified colocations between orthologs of GDP-l-galactose phosphorylase (GGP), dehydroascorbate reductase (DHAR), and nucleobase-ascorbate transporter within these QTL clusters. Of particular interest are the three paralogs of MdGGP, which all colocated within AsA-QTL clusters. Allelic variants of MdGGP1 and MdGGP3 derived from the cultivar Braeburn parent were also consistently associated with higher fruit total AsA concentrations both within the mapping population (up to 10-fold) and across a range of commercial apple germplasm (up to 6-fold). Striking differences in the expression of the cv Braeburn MdGGP1 allele between fruit from high- and low-AsA genotypes clearly indicate a key role for MdGGP1 in the regulation of fruit AsA concentrations, and this MdGGP allele-specific single-nucleotide polymorphism marker represents an excellent candidate for directed breeding for enhanced fruit AsA concentrations. Interestingly, colocations were also found between MdDHAR3-3 and a stable QTL for browning in the cv Telamon parent, highlighting links between the redox status of the AsA pool and susceptibility to flesh browning. PMID:23001142
Kiltz, U; van der Heijde, D; Boonen, A; Bautista-Molano, W; Burgos-Vargas, R; Chiowchanwisawakit, P; Duruoz, T; El-Zorkany, B; Essers, I; Gaydukova, I; Géher, P; Gossec, L; Grazio, S; Gu, J; Khan, M A; Kim, T J; Maksymowych, W P; Marzo-Ortega, H; Navarro-Compán, V; Olivieri, I; Patrikos, D; Pimentel-Santos, F M; Schirmer, M; van den Bosch, F; Weber, U; Zochling, J; Braun, J
2016-01-01
The Assessments of SpondyloArthritis international society Health Index (ASAS HI) measures functioning and health in patients with spondyloarthritis (SpA) across 17 aspects of health and 9 environmental factors (EF). The objective was to translate and adapt the original English version of the ASAS HI, including the EF Item Set, cross-culturally into 15 languages. Translation and cross-cultural adaptation has been carried out following the forward-backward procedure. In the cognitive debriefing, 10 patients/country across a broad spectrum of sociodemographic background, were included. The ASAS HI and the EF Item Set were translated into Arabic, Chinese, Croatian, Dutch, French, German, Greek, Hungarian, Italian, Korean, Portuguese, Russian, Spanish, Thai and Turkish. Some difficulties were experienced with translation of the contextual factors indicating that these concepts may be more culturally-dependent. A total of 215 patients with axial SpA across 23 countries (62.3% men, mean (SD) age 42.4 (13.9) years) participated in the field test. Cognitive debriefing showed that items of the ASAS HI and EF Item Set are clear, relevant and comprehensive. All versions were accepted with minor modifications with respect to item wording and response option. The wording of three items had to be adapted to improve clarity. As a result of cognitive debriefing, a new response option 'not applicable' was added to two items of the ASAS HI to improve appropriateness. This study showed that the items of the ASAS HI including the EFs were readily adaptable throughout all countries, indicating that the concepts covered were comprehensive, clear and meaningful in different cultures.
Kiltz, U; van der Heijde, D; Boonen, A; Bautista-Molano, W; Burgos-Vargas, R; Chiowchanwisawakit, P; Duruoz, T; El-Zorkany, B; Essers, I; Gaydukova, I; Géher, P; Gossec, L; Grazio, S; Gu, J; Khan, M A; Kim, T J; Maksymowych, W P; Marzo-Ortega, H; Navarro-Compán, V; Olivieri, I; Patrikos, D; Pimentel-Santos, F M; Schirmer, M; van den Bosch, F; Weber, U; Zochling, J; Braun, J
2016-01-01
Introduction The Assessments of SpondyloArthritis international society Health Index (ASAS HI) measures functioning and health in patients with spondyloarthritis (SpA) across 17 aspects of health and 9 environmental factors (EF). The objective was to translate and adapt the original English version of the ASAS HI, including the EF Item Set, cross-culturally into 15 languages. Methods Translation and cross-cultural adaptation has been carried out following the forward–backward procedure. In the cognitive debriefing, 10 patients/country across a broad spectrum of sociodemographic background, were included. Results The ASAS HI and the EF Item Set were translated into Arabic, Chinese, Croatian, Dutch, French, German, Greek, Hungarian, Italian, Korean, Portuguese, Russian, Spanish, Thai and Turkish. Some difficulties were experienced with translation of the contextual factors indicating that these concepts may be more culturally-dependent. A total of 215 patients with axial SpA across 23 countries (62.3% men, mean (SD) age 42.4 (13.9) years) participated in the field test. Cognitive debriefing showed that items of the ASAS HI and EF Item Set are clear, relevant and comprehensive. All versions were accepted with minor modifications with respect to item wording and response option. The wording of three items had to be adapted to improve clarity. As a result of cognitive debriefing, a new response option ‘not applicable’ was added to two items of the ASAS HI to improve appropriateness. Discussion This study showed that the items of the ASAS HI including the EFs were readily adaptable throughout all countries, indicating that the concepts covered were comprehensive, clear and meaningful in different cultures. PMID:27752358
NASA Technical Reports Server (NTRS)
Barhydt, Richard; Eischeid, Todd M.; Palmer, Michael T.; Wing, David J.
2003-01-01
NASA is currently investigating a new concept of operations for the National Airspace System, designed to improve capacity while maintaining or improving current levels of safety. This concept, known as Distributed Air/Ground Traffic Management (DAGTM), allows appropriately equipped autonomous aircraft to maneuver freely for flight optimization while resolving conflicts with other traffic and staying out of special use airspace and hazardous weather. In order to perform these tasks, pilots use prototype conflict detection, prevention, and resolution tools, collectively known as an Airborne Separation Assurance System (ASAS). While ASAS would normally allow pilots to resolve conflicts before they become hazardous, evaluation of system performance in sudden, near-term conflicts is needed in order to determine concept feasibility. An experiment was conducted in NASA Langley's Air Traffic Operations Lab to evaluate the prototype ASAS for enabling pilots to resolve near-term conflicts and examine possible operational effects associated with the use of lower separation minimums. Sixteen commercial airline pilots flew a total of 32 traffic scenarios that required them to use prototype ASAS tools to resolve close range pop-up conflicts. Required separation standards were set at either 3 or 5 NM lateral spacing, with 1000 ft vertical separation being used for both cases. Reducing the lateral separation from 5 to 3 NM did not appear to increase operational risk, as indicated by the proximity to the intruder aircraft. Pilots performed better when they followed tactical guidance cues provided by ASAS than when they didn't follow the guidance. In an effort to improve compliance rate, ASAS design changes are currently under consideration. Further studies will of evaluate these design changes and consider integration issues between ASAS and existing Airborne Collision Avoidance Systems (ACAS).
Luciani, M Gloria; Campregher, Christoph; Fortune, John M; Kunkel, Thomas A; Gasche, Christoph
2007-01-01
Individuals with inflammatory bowel disease are at risk of developing colorectal cancer (CRC). Epidemiologic, animal, and laboratory studies suggest that 5-amino-salicylic acid (5-ASA) protects from the development of CRC by altering cell cycle progression and by inducing apoptosis. Our previous results indicate that 5-ASA improves replication fidelity in colorectal cells, an effect that is active in reducing mutations. In this study, we hypothesized that 5-ASA restrains cell cycle progression by activating checkpoint pathways in colorectal cell lines, which would prevent tumor development and improve genomic stability. CRC cells with different genetic backgrounds such as HT29, HCT116, HCT116(p53-/-), HCT116+chr3, and LoVo were treated with 5-ASA for 2-96 hours. Cell cycle progression, phosphorylation, and DNA binding of cell cycle checkpoint proteins were analyzed. We found that 5-ASA at concentrations between 10 and 40 mmol/L affects cell cycle progression by inducing cells to accumulate in the S phase. This effect was independent of the hMLH1, hMSH2, and p53 status because it was observed to a similar extent in all cell lines under investigation. Moreover, wash-out experiments demonstrated reversibility within 48 hours. Although p53 did not have a causative role, p53 Ser15 was strongly phosphorylated. Proteins involved in the ATM-and-Rad3-related kinase (ATR)-dependent S-phase checkpoint response (Chk1 and Rad17) were also phosphorylated but not ataxia telengectasia mutated kinase. Our data demonstrate that 5-ASA causes cells to reversibly accumulate in S phase and activate an ATR-dependent checkpoint. The activation of replication checkpoint may slow down DNA replication and improve DNA replication fidelity, which increases the maintenance of genomic stability and counteracts carcinogenesis.
Patent foramen ovale and the risk of ischemic stroke in a multiethnic population.
Di Tullio, Marco R; Sacco, Ralph L; Sciacca, Robert R; Jin, Zhezhen; Homma, Shunichi
2007-02-20
We sought to assess the risk of ischemic stroke from a patent foramen ovale (PFO) in the multiethnic prospective cohort of northern Manhattan. Patent foramen ovale has been associated with increased risk of ischemic stroke, mainly in case-control studies. The actual PFO-related stroke risk in the general population is unclear. The presence of PFO was assessed at baseline by using transthoracic 2-dimensional echocardiography with contrast injection in 1,100 stroke-free subjects older than 39 years of age (mean age 68.7 +/- 10.0 years) from the Northern Manhattan Study (NOMAS). The presence of atrial septal aneurysm (ASA) also was recorded. Subjects were followed annually for outcomes. We assessed PFO/ASA-related stroke risk after adjusting for established stroke risk factors. We detected PFO in 164 subjects (14.9%); ASA was present in 27 subjects (2.5%) and associated with PFO in 19 subjects. During a mean follow-up of 79.7 +/- 28.0 months, an ischemic stroke occurred in 68 subjects (6.2%). After adjustment for demographics and risk factors, PFO was not found to be significantly associated with stroke (hazard ratio 1.64, 95% confidence interval [CI] 0.87 to 3.09). The same trend was observed in all age, gender, and race-ethnic subgroups. The coexistence of PFO and ASA did not increase the stroke risk (adjusted hazard ratio 1.25, 95% CI 0.17 to 9.24). Isolated ASA was associated with elevated stroke incidence (2 of 8, or 25%; adjusted hazard ratio 3.66, 95% CI 0.88 to 15.30). Patent foramen ovale, alone or together with ASA, was not associated with an increased stroke risk in this multiethnic cohort. The independent role of ASA needs further assessment in appositely designed and powered studies.
NASA Technical Reports Server (NTRS)
Snow, W. L.
1974-01-01
The mutual diffusion of two reacting gases is examined which takes place in a bath of inert gas atoms. Solutions are obtained between concentric spheres, each sphere acting as a source for one of the reactants. The calculational model is used to illustrate severe number density gradients observed in absorption experiments with alkali vapor. Severe gradients result when sq root k/D R is approximately 5 where k, D, and R are respectively the second order rate constant, the multicomponent diffusion constant, and the geometrical dimension of the experiment.
Hameed, Abdul; Gulzar, Salman; Aziz, Irfan; Hussain, Tabassum; Gul, Bilquees; Khan, M. Ajmal
2015-01-01
Salinity causes oxidative stress in plants by enhancing production of reactive oxygen species, so that an efficient antioxidant system, of which ascorbic acid (AsA) is a key component, is an essential requirement of tolerance. However, antioxidant responses of plants to salinity vary considerably among species. Limonium stocksii is a sub-tropical halophyte found in the coastal marshes from Gujarat (India) to Karachi (Pakistan) but little information exists on its salt resistance. In order to investigate the role of AsA in tolerance, 2-month-old plants were treated with 0 (control), 300 (moderate) and 600 (high) mM NaCl for 30 days with or without exogenous application of AsA (20 mM) or distilled water. Shoot growth of unsprayed plants at moderate salinity was similar to that of controls while at high salinity growth was inhibited substantially. Sap osmolality, AsA concentrations and activities of AsA-dependant antioxidant enzymes increased with increasing salinity. Water spray resulted in some improvement in growth, indicating that the growth promotion by exogenous treatments could partly be attributed to water. However, exogenous application of AsA on plants grown under saline conditions improved growth and AsA dependent antioxidant enzymes more than the water control treatment. Our data show that AsA-dependent antioxidant enzymes play an important role in salinity tolerance of L. stocksii. PMID:25603966
Rahmani, M A; David, V; Huang, M; DeGray, G
1998-01-01
The effects of acetylsalicylic acid (ASA) on aortic smooth muscle contractility were studied in aortic rings of male SHR and WKY rats. The rats were administered two intraperitoneal injections of 10 mg/kg of ASA per week for ten weeks. Blood pressure of each rat was monitored twice weekly prior to the i.p. injections. Twenty four hours after the last injection the aortic smooth muscles were evaluated for generation of active tension in response to KCl, Phenylephrine (PE), Clonidine and Norepinephrine (NE). In another set of experiments calcium conductance was evaluated in the presence or absence of endothelium both in ASA treated and non treated animals. We report that aortic rings from ASA-treated SHR animals were more responsive to contractile agents than rings from non-treated SHR male rats. Also, the Ca2+ conductance in vitro was enhanced appreciably in SHR aortic rings denuded of their monolayer of endothelium in response to ASA treatment. No decrease in systolic blood pressure was observed in response to ASA treatment in SHR male rats. These results suggest that acetylsalicylic acid not only may modulate aortic smooth muscle contractility through the metabolites of arachidonic acid but may repair to a great extent the hypertension associated plasma membrane permeability defect of vascular myocytes.
Maloney, Susan E; Creeley, Catherine E; Hartman, Richard E; Yuede, Carla M; Zorumski, Charles F; Jevtovic-Todorovic, Vesna; Dikranian, Krikor; Noguchi, Kevin K; Farber, Nuri B; Wozniak, David F
2018-03-14
Fifteen years ago Olney and colleagues began using animal models to evaluate the effects of anesthetic and sedative agents (ASAs) on neurodevelopment. The results from ongoing studies indicate that, under certain conditions, exposure to these drugs during development induces an acute elevated apoptotic neurodegenerative response in the brain and long-term functional impairments. These animal models have played a significant role in bringing attention to the possible adverse effects of exposing the developing brain to ASAs when few concerns had been raised previously in the medical community. The apoptotic degenerative response resulting from neonatal exposure to ASAs has been replicated in many studies in both rodents and non-human primates, suggesting that a similar effect may occur in humans. In both rodents and non-human primates, significantly increased levels of apoptotic degeneration are often associated with functional impairments later in life. However, behavioral deficits following developmental ASA exposure have not been consistently reported even when significantly elevated levels of apoptotic degeneration have been documented in animal models. In the present work, we review this literature and propose a rodent model for assessing potential functional deficits following neonatal ASA exposure with special reference to experimental design and procedural issues. Our intent is to improve test sensitivity and replicability for detecting subtle behavioral effects, and thus enhance the translational significance of ASA models. Copyright © 2018 Elsevier Inc. All rights reserved.
Gilmore, Amanda K; Stappenbeck, Cynthia A; Lewis, Melissa A; Granato, Hollie F; Kaysen, Debra
2015-05-01
The current study examined the relationship between sexual assault history and drinking protective behavioral strategies (PBS). Given the relationship between sexual assault history and alcohol use, we hypothesized that after we controlled for drinking behavior, women with a childhood sexual abuse (CSA) history would use fewer drinking PBS than those without a CSA history. We also hypothesized that a history of adolescent/adult sexual assault (ASA) involving incapacitation and force would be associated with lower use of drinking PBS after controlling for CSA history and drinking behavior. A total of 800 undergraduate college women completed a survey online. Regression analyses indicated that the only sexual assault history type that was consistently related to all three types of drinking PBS was ASA involving incapacitation. Women with a history of incapacitated ASA were less likely to use any type of drinking PBS than women without such history. A history of other types of sexual assault (CSA, physically forced ASA, and verbally coerced ASA) was associated only with lower use of serious harm-reduction drinking PBS, such as going home with a friend or knowing the location of your drink. This was the first study to examine the relationship between different sexual assault histories and drinking PBS, and it furthers our understanding of the relationship between alcohol and sexual assault. Possible reasons for this relationship between ASA and PBS use are discussed.
Do non-steroidal anti-inflammatory drugs influence the steroid hormone milieu in male athletes?
Di Luigi, L; Rossi, C; Sgrò, P; Fierro, V; Romanelli, F; Baldari, C; Guidetti, L
2007-10-01
Prostaglandins modulate the hypothalamus-pituitary-adrenal and -gonadal axis pathways. We explored the effects of a single course of treatment with acetylsalicylic acid (ASA), an inhibitor of prostaglandin synthesis, on the steroid milieu in athletes. Morning plasma cortisol (F), dehydroepiandrosterone sulphate, free-testosterone, testosterone (T) and their ratios were evaluated before and after the administration of either ASA or placebo in twelve male athletes, when affected by minor musculoskeletal trauma and, as control, after a five/six week wash-out in healthy conditions respectively. One tablet of ASA (800 mg), or placebo, was administered two times daily for 10 days during treatment. All the volunteers suspended exercise training during treatment. The results revealed that compared to placebo, plasma F was significantly lower after ASA treatment (p = 0.023). Furthermore, the comparison of hormone's absolute and percentage of variations (Delta and Delta%) between ASA and placebo treatment showed significant differences respectively for DeltaF (p = 0.045), for DeltaT (p = 0.047), for DeltaT/F (p = 0.042), for DeltaF% (p = 0.04) and for DeltaT% (p = 0.049). Our data suggest that in comparison to placebo, a short-term ASA treatment is able to influence the plasma steroid milieu in athletes. Due to the observed variability of the individual hormonal patterns, further research is required to substantiate these findings.
Anagrelide reduces thrombotic risk in essential thrombocythaemia vs. hydroxyurea plus aspirin.
Dombi, Péter; Illés, Árpád; Demeter, Judit; Homor, Lajos; Simon, Zsofia; Karadi, Eva; Udvardy, Miklos; Egyed, Miklos
2017-02-01
To evaluate the reduction in thrombotic events (TE) in patients with essential thrombocythaemia (ET) treated with anagrelide versus hydroxyurea + aspirin (HU + ASA). A questionnaire was developed using 2008 WHO diagnostic criteria, and thrombotic risk factors were stratified according to Landolfi criteria. Through questionnaire completion, clinicians at Hungarian haematological centres entered data into the Hungarian MPN Registry on patients with myeloproliferative neoplasms. Based on ET registry data, TEs in anagrelide-treated patients (n = 139) were compared with HU + ASA-treated patients (n = 141). Patients were followed up for (median) 6 yr. TEs were reported in significantly fewer anagrelide-treated patients versus HU + ASA (15.1% versus 49.6%; P < 0.001). Numbers of major arterial and major venous events were similar between the groups, although there were over fivefold more minor arterial and minor venous events in the HU + ASA group (P < 0.001). While median age at diagnosis was older and length of follow-up shorter in the HU + ASA group (P < 0.05), this did not influence TE incidence; medication and TE before diagnosis only influenced TE incidence. Anagrelide significantly decreased the number of patients experiencing minor arterial and minor venous TEs versus HU + ASA over 6 yr. Risk of TE after diagnosis was significantly increased if the patient had TE before diagnosis. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Akiyama, Satoko; Uehara, Mariko; Katsumata, Shin-ichi; Ihara, Hiroshi; Hashizume, Naotaka; Suzuki, Kazuharu
2008-12-01
We investigated the effects of ascorbic acid (AsA) supplementation on lipid peroxidation and the lipid content in the liver and serum of magnesium (Mg)-deficient rats. Eighteen 3-week-old male Sprague-Dawley strain rats were divided into 3 groups and maintained on a control diet (C group), a low-Mg diet (D group), or a low-Mg diet supplemented with AsA (DA group) for 42 d. At the end of this period, the final body weight, weight gain, and serum Mg concentrations were significantly decreased in the Mg-deficient rats. Further, dietary AsA supplementation had no effect on the growth, serum Mg concentration, Mg absorption, and Mg retention. The serum concentration of AsA was significantly lower in the D group than in the C group but was unaltered in the DA group. The levels of phosphatidylcholine hydroperoxide (PCOOH) in the serum and of triglycerides (TGs) and total cholesterol (TC) in the serum and liver were significantly higher in the D group than in the C group. The serum PCOOH, liver TG, and liver TC levels were decreased in the DA group. These results indicate that Mg deficiency increases the AsA requirement of the body and that AsA supplementation normalizes the serum levels of PCOOH and the liver lipid content in Mg-deficient rats, without altering the Mg status.
Effective conductivity of suspensions of hard spheres by Brownian motion simulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chan Kim, I.; Torquato, S.
1991-02-15
A generalized Brownian motion simulation technique developed by Kim and Torquato (J. Appl. Phys. {bold 68}, 3892 (1990)) is applied to compute exactly'' the effective conductivity {sigma}{sub {ital e}} of heterogeneous media composed of regular and random distributions of hard spheres of conductivity {sigma}{sub 2} in a matrix of conductivity {sigma}{sub 1} for virtually the entire volume fraction range and for several values of the conductivity ratio {alpha}={sigma}{sub 2}/{sigma}{sub 1}, including superconducting spheres ({alpha}={infinity}) and perfectly insulating spheres ({alpha}=0). A key feature of the procedure is the use of {ital first}-{ital passage}-{ital time} equations in the two homogeneous phases andmore » at the two-phase interface. The method is shown to yield {sigma}{sub {ital e}} accurately with a comparatively fast execution time. The microstructure-sensitive analytical approximation of {sigma}{sub {ital e}} for dispersions derived by Torquato (J. Appl. Phys. {bold 58}, 3790 (1985)) is shown to be in excellent agreement with our data for random suspensions for the wide range of conditions reported here.« less
Integrating spheres for improved skin photodynamic therapy
NASA Astrophysics Data System (ADS)
Glennie, Diana L.; Farrell, Thomas J.; Hayward, Joseph E.; Patterson, Michael S.
2010-09-01
The prescribed radiant exposures for photodynamic therapy (PDT) of superficial skin cancers are chosen empirically to maximize the success of the treatment while minimizing adverse reactions for the majority of patients. They do not take into account the wide range of tissue optical properties for human skin, contributing to relatively low treatment success rates. Additionally, treatment times can be unnecessarily long for large treatment areas if the laser power is not sufficient. Both of these concerns can be addressed by the incorporation of an integrating sphere into the irradiation apparatus. The light fluence rate can be increased by as much as 100%, depending on the tissue optical properties. This improvement can be determined in advance of treatment by measuring the reflectance from the tissue through a side port on the integrating sphere, allowing for patient-specific treatment times. The sphere is also effective at improving beam flatness, and reducing the penumbra, creating a more uniform light field. The side port reflectance measurements are also related to the tissue transport albedo, enabling an approximation of the penetration depth, which is useful for real-time light dosimetry.
Tuning the phase diagram of colloid-polymer mixtures via Yukawa interactions
NASA Astrophysics Data System (ADS)
González García, Álvaro; Tuinier, Remco
2016-12-01
Theory that predicts the phase behavior of interacting Yukawa spheres in a solution containing nonadsorbing polymer is presented. Our approach accounts for multiple overlap of depletion zones. It is found that additional Yukawa interactions beyond hard core interactions strongly affect the location and presence of coexistence regions and phase states. The theoretical phase diagrams are compared with Monte Carlo simulations. The agreement between the two approaches supports the validity of the theoretical approximations made and confirms that, by choosing the parameters of the interaction potentials, tuning of the binodals is possible. The critical end point characterizes the phase diagram topology. It is demonstrated how an additional Yukawa interaction shifts this point with respect to the hard sphere case. Provided a certain depletant-to-colloid size ratio for which a stable colloidal gas-liquid phase coexistence takes place for hard spheres, added direct interactions turn this into a metastable gas-liquid equilibrium. The opposite case, the induction of a stable gas-liquid coexistence where only fluid-solid was present for hard spheres, is also reported.
NASA Astrophysics Data System (ADS)
Takano, Y.; Liou, K. N.; Kahnert, M.; Yang, P.
2013-08-01
The single-scattering properties of eight black carbon (BC, soot) fractal aggregates, composed of primary spheres from 7 to 600, computed by the geometric-optics surface-wave (GOS) approach coupled with the Rayleigh-Gans-Debye (RGD) adjustment for size parameters smaller than approximately 2, are compared with those determined from the superposition T-matrix method. We show that under the condition of random orientation, the results from GOS/RGD are in general agreement with those from T-matrix in terms of the extinction and absorption cross-sections, the single-scattering co-albedo, and the asymmetry factor. When compared with the specific absorption (m2/g) measured in the laboratory, we illustrate that using the observed radii of primary spheres ranging from 3.3 to 25 nm, the theoretical values determined from GOS/RGD for primary sphere numbers of 100-600 are within the range of measured values. The GOS approach can be effectively applied to aggregates composed of a large number of primary spheres (e.g., >6000) and large size parameters (≫2) in terms of computational efforts.
Zhou, Lin; Duan, Xingmei; Zeng, Shi; Men, Ke; Zhang, Xueyan; Yang, Li; Li, Xiang
2015-01-01
Natural product curcumin (Cur) and H2S-releasing prodrug SH-aspirin (SH-ASA) are potential anticancer agents with diverse mechanisms, but their clinical application prospects are restricted by hydrophobicity and limited efficiency. In this work, we coencapsulated SH-ASA and Cur into methoxy poly(ethylene glycol)-poly (lactide-coglycolide) (mPEG-PLGA) nanoparticles through a modified oil-in-water single-emulsion solvent evaporation process. The prepared SH-ASA/Cur-coloaded mPEG-PLGA nanoparticles had a mean particle size of 122.3±6.8 nm and were monodispersed (polydispersity index =0.179±0.016) in water, with high drug-loading capacity and stability. Intriguingly, by treating with SH-ASA/Cur-coloaded mPEG-PLGA nanoparticles, obvious synergistic anticancer effects on ES-2 and SKOV3 human ovarian carcinoma cells were observed in vitro, and activation of the mitochondrial apoptosis pathway was indicated. Our results demonstrated that SH-ASA/Cur-coloaded mPEG-PLGA nanoparticles could have potential clinical advantages for the treatment of ovarian cancer.
Zhou, Lin; Duan, Xingmei; Zeng, Shi; Men, Ke; Zhang, Xueyan; Yang, Li; Li, Xiang
2015-01-01
Natural product curcumin (Cur) and H2S-releasing prodrug SH-aspirin (SH-ASA) are potential anticancer agents with diverse mechanisms, but their clinical application prospects are restricted by hydrophobicity and limited efficiency. In this work, we coencapsulated SH-ASA and Cur into methoxy poly(ethylene glycol)-poly (lactide-coglycolide) (mPEG-PLGA) nanoparticles through a modified oil-in-water single-emulsion solvent evaporation process. The prepared SH-ASA/Cur-coloaded mPEG-PLGA nanoparticles had a mean particle size of 122.3±6.8 nm and were monodispersed (polydispersity index =0.179±0.016) in water, with high drug-loading capacity and stability. Intriguingly, by treating with SH-ASA/Cur-coloaded mPEG-PLGA nanoparticles, obvious synergistic anticancer effects on ES-2 and SKOV3 human ovarian carcinoma cells were observed in vitro, and activation of the mitochondrial apoptosis pathway was indicated. Our results demonstrated that SH-ASA/Cur-coloaded mPEG-PLGA nanoparticles could have potential clinical advantages for the treatment of ovarian cancer. PMID:26316750
Test of simple fluid theories for the Lennard-Jones system
NASA Astrophysics Data System (ADS)
Malijevský, A.; Labik, S.
1988-03-01
A test is made of a new version of the reference-hypernetted chain approximation (RHNC) with minimized free energy proposed by Lado, Foiles and Ashcroft. An accurate relationship is used for the bridge function of the reference hard spheres. The calculated values of the compressibility factor and the internal energy are compared with simulation data, with results of the exponential approximation of Andersen et al., and with results of the Madden-Fitts approximation. The RHNC provides the most reliable results over wide ranges of reduced temperatures and densities.
Hart, Francis X; Easterly, Clay E
2004-05-01
The electric field pulse shape and change in transmembrane potential produced at various points within a sphere by an intense, ultrawideband pulse are calculated in a four stage, analytical procedure. Spheres of two sizes are used to represent the head of a human and the head of a rat. In the first stage, the pulse is decomposed into its Fourier components. In the second stage, Mie scattering analysis (MSA) is performed for a particular point in the sphere on each of the Fourier components, and the resulting electric field pulse shape is obtained for that point. In the third stage, the long wavelength approximation (LWA) is used to obtain the change in transmembrane potential in a cell at that point. In the final stage, an energy analysis is performed. These calculations are performed at 45 points within each sphere. Large electric fields and transmembrane potential changes on the order of a millivolt are produced within the brain, but on a time scale on the order of nanoseconds. The pulse shape within the brain differs considerably from that of the incident pulse. Comparison of the results for spheres of different sizes indicates that scaling of such pulses across species is complicated. Published 2004 Wiley-Liss, Inc.
Nurok, Michael; Green, Douglas S T; Chisholm, Mary F; Fins, Joseph J; Liguori, Gregory A
2014-05-01
To assess anesthesiologists' familiarity with the American Society of Anesthesiologists (ASA) and American College of Surgeons (ACS) guidelines on Advance Directives in the perioperative setting. Single-center, 4-question anonymous survey. Urban academic medical center. Up to 34 subjects responded to each question. Familiarity with the ASA and ACS guidelines on Advance Directives in the perioperative setting ranged from 45% to 100%. There was inadequate familiarity with components of the ASA and ACS guidelines on advance directives in the perioperative setting. Larger studies are required to assess anesthesiologists' familiarity with national society guidelines that directly affect patient care. Future work should investigate best practices for guideline implementation, and consequences of poor adherence to national guidelines. Copyright © 2014 Elsevier Inc. All rights reserved.
The ASAS-SN Bright Supernova Catalog – II. 2015
Holoien, T. W. -S.; Brown, J. S.; Stanek, K. Z.; ...
2017-01-16
Here, this paper presents information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during 2015, its second full year of operations. The same information is presented for bright (mV ≤ 17), spectroscopically confirmed supernovae discovered by other sources in 2015. As with the first ASAS-SN bright supernova catalogue, we also present redshifts and near-ultraviolet through infrared magnitudes for all supernova host galaxies in both samples. Combined with our previous catalogue, this work comprises a complete catalogue of 455 supernovae from multiple professional and amateur sources, allowing for population studies that were previously impossible. This is themore » second of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team.« less
The ASAS-SN Bright Supernova Catalog – II. 2015
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holoien, T. W. -S.; Brown, J. S.; Stanek, K. Z.
Here, this paper presents information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during 2015, its second full year of operations. The same information is presented for bright (mV ≤ 17), spectroscopically confirmed supernovae discovered by other sources in 2015. As with the first ASAS-SN bright supernova catalogue, we also present redshifts and near-ultraviolet through infrared magnitudes for all supernova host galaxies in both samples. Combined with our previous catalogue, this work comprises a complete catalogue of 455 supernovae from multiple professional and amateur sources, allowing for population studies that were previously impossible. This is themore » second of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team.« less
Shahabadi, Nahid; Fili, Soraya Moradi; Kheirdoosh, Fahimeh
2013-11-05
The interaction of CT-DNA with the drug mesalamine (5-ASA) at physiological pH has been investigated by absorption, emission, circular dichroism (CD), cyclic voltammetry (CV), viscosity studies and molecular modeling. Thermodynamic parameters (ΔH>0 and ΔS<0) indicated that hydrogen bond and van der Waals play main roles in the binding of 5-ASA to CT-DNA. Ethidium bromide (EB) displacement studies revealed that 5-ASA did not have any effect on ethidium bromide (EB) bound DNA which is indicative of groove binding. The results obtained from experimental and molecular modeling showed that 5-ASA is a minor groove binder of DNA and preferentially binds to GC rich regions. Copyright © 2013 Elsevier B.V. All rights reserved.
Does ASA classification impact success rates of endovascular aneurysm repairs?
Conners, Michael S; Tonnessen, Britt H; Sternbergh, W Charles; Carter, Glen; Yoselevitz, Moises; Money, Samuel R
2002-09-01
The purpose of this study was to evaluate the technical success, clinical success, postoperative complication rate, need for a secondary procedure, and mortality rate with endovascular aneurysm repair (EAR), based on the physical status classification scheme advocated by the American Society of Anesthesiologists (ASA). At a single institution 167 patients underwent attempted EAR. Query of a prospectively maintained database supplemented with a retrospective review of medical records was used to gather statistics pertaining to patient demographics and outcome. In patients selected for EAR on the basis of acceptable anatomy, technical and clinical success rates were not significantly different among the different ASA classifications. Importantly, postoperative complication and 30-day mortality rates do not appear to significantly differ among the different ASA classifications in this patient population.
Xie, Xiande; Hu, Yuanan; Cheng, Hefa
2016-02-01
Although banned in some developed countries, p-arsanilic acid (p-ASA) is still used widely as a feed additive for swine production in many countries. With little uptake and transformation in animal bodies, nearly all the p-ASA administered to animals is excreted chemically unchanged in animal wastes, which can subsequently release the more toxic inorganic arsenic species upon degradation in the environment. For safe disposal of the animal wastes laden with p-ASA, we proposed a method of leaching the highly water-soluble p-ASA out of the manure first, followed by treatment of the leachate using the Fenton process to achieve fast oxidation of p-ASA and removal of the inorganic arsenic species released (predominantly arsenate) from solution simultaneously. The effects of solution pH, dosages of H2O2 and Fe(2+), and the presence of dissolved organic matter (DOM) on the treatment efficiency were systematically investigated. Under the optimum treatment conditions (0.53 mmol L(-1) Fe(2+), 2.12 mmol L(-1) H2O2, and initial pH of 3.0), p-ASA (10 mg-As L(-1)) could be completely oxidized to As(V) within 30 min in pure water and 4 natural water samples, and at the final pH of 4.0, the residual arsenic levels in solution phase were as low as 1.1 and 20.1-43.4 μg L(-1) in the two types of water matrixes, respectively. The presence of humic acid significantly retarded the oxidation of p-ASA by scavenging HO, and inhibited the As(V) removal through competitive adsorption on ferric hydroxide. Due to the high contents of DOM in the swine manure leachate samples (TOC at ∼500 mg L(-1)), much higher dosages of Fe(2+) (10.0 mmol L(-1)) and H2O2 (40.0 mmol L(-1)) and a longer treatment time (120 min) were required to achieve near complete oxidation of p-ASA (98.0%), while maintaining the levels of residual arsenic in the solution at <70.0 μg L(-1). The degradation pathway of p-ASA in the Fenton process was proposed based on the major degradation products detected. Together, the results demonstrate that the Fenton process is promising as an efficient, robust, and low-cost treatment method for controlling the risk of p-ASA in the animal wastes generated at factory farms. Copyright © 2015 Elsevier Ltd. All rights reserved.
Rhombohedrally Distorted γ-Au 5–x Zn 8+y Phases in the Au–Zn System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thimmaiah, Srinivasa; Miller, Gordon J.
2013-02-04
The region of the Au–Zn phase diagram encompassing γ-brass-type phases has been studied experimentally from 45 to 85 atom % Zn. The γ phases were obtained directly from the pure elements by heating to 680 °C in evacuated silica tubes, followed by annealing at 300 °C. Powder X-ray and single-crystal diffraction studies show that γ-“Au5Zn8” phases adopt a rhombohedrally distorted Cr5Al8 structure type rather than the cubic Cu5Zn8 type. The refined compositions from two single crystals extracted from the Zn- and Au-rich loadings are Au4.27(3)Zn8.26(3)γ0.47 (I) and Au4.58(3)Zn8.12(3)γ0.3 (II), respectively (γ = vacancy). These (I and II) refinements indicated bothmore » nonstatistical mixing of Au and Zn atoms as well as partially ordered vacancy distributions. The structures of these γ phases were solved in the acentric space group R3m (No. 160, Z = 6), and the observed lattice parameters from powder patterns were found to be a = 13.1029(6) and 13.1345(8) Å and c = 8.0410(4) and 8.1103(6) Å for crystals I and II, respectively. According to single-crystal refinements, the vacancies were found on the outer tetrahedron (OT) and octahedron (OH) of the 26-atom cluster. Single-crystal structural refinement clearly showed that the vacancy content per unit cell increases with increasing Zn, or valence-electron concentration. Electronic structure calculations, using the tight-binding linear muffin-tin orbital method with the atomic-sphere approximation (TB-LMTO-ASA) method, indicated the presence of a well-pronounced pseudogap at the Fermi level for “Au5Zn8” as the representative composition, an outcome that is consistent with the Hume–Rothery interpretation of γ brass.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Samal, Saroj L.; Corbett, John D.
Na{sub 6}Cd{sub 16}Au{sub 7} has been synthesized via typical high-temperature reactions, and its structure refined by single crystal X-ray diffraction as cubic, Fm{bar 3}m, a = 13.589(1) {angstrom}, Z = 4. The structure consists of Cd{sub 8} tetrahedral star (TS) building blocks that are face capped by six shared gold (Au2) vertexes and further diagonally bridged via Au1 to generate an orthogonal, three-dimensional framework [Cd{sub 8}(Au2){sub 6/2}(Au1){sub 4/8}], an ordered ternary derivative of Mn{sub 6}Th{sub 23}. Linear muffin-tin-orbital (LMTO)-atomic sphere approximation (ASA) electronic structure calculations indicate that Na{sub 6}Cd{sub 16}Au{sub 7} is metallic and that {approx}76% of the total crystalmore » orbital Hamilton populations (-ICOHP) originate from polar Cd-Au bonding with 18% more from fewer Cd-Cd contacts. Na{sub 6}Cd{sub 16}Au{sub 7} (45 valence electron count (vec)) is isotypic with the older electron-richer Mg{sub 6}Cu{sub 16}Si{sub 7} (56 vec) in which the atom types are switched and bonding characteristics among the network elements are altered considerably (Si for Au, Cu for Cd, Mg for Na). The earlier and more electronegative element Au now occupies the Si site, in accord with the larger relativistic bonding contributions from polar Cd-Au versus Cu-Si bonds with the neighboring Cd in the former Cu positions. Substantial electronic differences in partial densities-of-states (PDOS) and COHP data for all atoms emphasize these. Strong contributions of nearby Au 5d{sup 10} to bonding states without altering the formal vec are the likely origin of these effects.« less
2000-05-31
direction for the Office of the ASA (FM&C), consolidate all of the office’s subordinate organization strategic plans, and better define the roles and...responsibilities within the office of the ASA(FM&C). Mrs. McCoy directed Ms. Barbara Bonessa, Chief of the Financial Management Redesign Office, to...lead the strategic planning effort. Ms. Bonessa built a strategic planning team primarily with strategic management expertise from outside of the office of
State-of-the-Art Resources (SOAR) for Software Vulnerability Detection, Test, and Evaluation
2014-07-01
preclude in-depth analysis, and widespread use of a Software -as-a- Service ( SaaS ) model that limits data availability and application to DoD systems...provide mobile application analysis using a Software - as-a- Service ( SaaS ) model. In this case, any software to be analyzed must be sent to the...tools are only available through a SaaS model. The widespread use of a Software -as-a- Service ( SaaS ) model as a sole evaluation model limits data
BOREAS RSS-2 Level-1B ASAS Image Data: At-Sensor Radiance in BSQ Format
NASA Technical Reports Server (NTRS)
Russell, C.; Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Dabney, P. W.; Kovalick, W.; Graham, D.; Bur, Michael; Irons, James R.; Tierney, M.
2000-01-01
The BOREAS RSS-2 team used the ASAS instrument, mounted on the NASA C-130 aircraft, to create at-sensor radiance images of various sites as a function of spectral wavelength, view geometry (combinations of view zenith angle, view azimuth angle, solar zenith angle, and solar azimuth angle), and altitude. The level-1b ASAS images of the BOREAS study areas were collected from April to September 1994 and March to July 1996.
Piao, Daqing; Barbour, Randall L.; Graber, Harry L.; Lee, Daniel C.
2015-01-01
Abstract. This work analytically examines some dependences of the differential pathlength factor (DPF) for steady-state photon diffusion in a homogeneous medium on the shape, dimension, and absorption and reduced scattering coefficients of the medium. The medium geometries considered include a semi-infinite geometry, an infinite-length cylinder evaluated along the azimuthal direction, and a sphere. Steady-state photon fluence rate in the cylinder and sphere geometries is represented by a form involving the physical source, its image with respect to the associated extrapolated half-plane, and a radius-dependent term, leading to simplified formula for estimating the DPFs. With the source-detector distance and medium optical properties held fixed across all three geometries, and equal radii for the cylinder and sphere, the DPF is the greatest in the semi-infinite and the smallest in the sphere geometry. When compared to the results from finite-element method, the DPFs analytically estimated for 10 to 25 mm source–detector separations on a sphere of 50 mm radius with μa=0.01 mm−1 and μs′=1.0 mm−1 are on average less than 5% different. The approximation for sphere, generally valid for a diameter ≥20 times of the effective attenuation pathlength, may be useful for rapid estimation of DPFs in near-infrared spectroscopy of an infant head and for short source–detector separation. PMID:26465613
A Canadian adaptation of the Automated Self-Administered 24-hour Dietary Assessment Tool (ASA24-Canada), developed by the Food Directorate at Health Canada in collaboration with NCI, has been freely available since April 2014.
Palus, Katarzyna; Całka, Jarosław
2015-01-01
This experiment was designed to establish the localization and neurochemical phenotyping of sympathetic neurons supplying prepyloric area of the porcine stomach in a physiological state and during acetylsalicylic acid (ASA) induced gastritis. In order to localize the sympathetic perikarya the stomachs of both control and acetylsalicylic acid treated (ASA group) animals were injected with neuronal retrograde tracer Fast Blue (FB). Seven days post FB injection, animals were divided into a control and ASA supplementation group. The ASA group was given 100 mg/kg of b.w. ASA orally for 21 days. On the 28th day all pigs were euthanized with gradual overdose of anesthetic. Then fourteen-micrometer-thick cryostat sections were processed for routine double-labeling immunofluorescence, using primary antisera directed towards tyrosine hydroxylase (TH), dopamine β-hydroxylase (DβH), neuropeptide Y (NPY), galanin (GAL), neuronal nitric oxide synthase (nNOS), leu 5-enkephalin (LENK), cocaine- and amphetamine- regulated transcript peptide (CART), calcitonin gene-related peptide (CGRP), substance P (SP) and vasoactive intestinal peptide (VIP). The data obtained in this study indicate that postganglionic sympathetic nerve fibers supplying prepyloric area of the porcine stomach originate from the coeliac-cranial mesenteric ganglion complex (CCMG). In control animals, the FB-labelled neurons expressed TH (94.85 ± 1.01%), DβH (97.10 ± 0.97%), NPY (46.88 ± 2.53%) and GAL (8.40 ± 0.53%). In ASA group, TH- and DβH- positive nerve cells were reduced (85.78 ± 2.65% and 88.82 ± 1.63% respectively). Moreover, ASA- induced gastritis resulted in increased expression of NPY (76.59 ± 3.02%) and GAL (26.45 ± 2.75%) as well as the novo-synthesis of nNOS (6.13 ± 1.11%) and LENK (4.77 ± 0.42%) in traced CCMG neurons. Additionally, a network of CART-, CGRP-, SP-, VIP-, LENK-, nNOS- immunoreactive (IR) nerve fibers encircling the FB-positive perikarya were observed in both intact and ASA-treated animals. The results of this study indicate involvement of these neuropeptides in the development or presumably counteraction of gastric inflammation.
Rossini, Roberta; Iorio, Annamaria; Pozzi, Roberto; Bianco, Matteo; Musumeci, Giuseppe; Leonardi, Sergio; Lettieri, Corrado; Bossi, Irene; Colombo, Paola; Rigattieri, Stefano; Dossena, Cinzia; Anzuini, Angelo; Capodanno, Davide; Senni, Michele; Angiolillo, Dominick J
2017-02-01
There are limited data on aspirin (ASA) desensitization for patients with coronary artery disease. The aim of the present study was to assess the safety and efficacy of a standard rapid desensitization protocol in patients with ASA sensitivity undergoing coronary angiography. This is a prospective, multicenter, observational study including 7 Italian centers including patients with a history of ASA sensitivity undergoing coronary angiography with intent to undergo percutaneous coronary intervention. A total of 330 patients with history of ASA sensitivity with known/suspected stable coronary artery disease or presenting with an acute coronary syndrome, including ST-segment-elevation myocardial infarction were enrolled. Adverse effects to aspirin included urticaria (n=177, 53.6%), angioedema (n=69, 20.9%), asthma (n=65, 19.7%), and anaphylactic reaction (n=19, 5.8%). Among patients with urticaria/angioedema, 13 patients (3.9%) had a history of idiopathic chronic urticaria. All patients underwent a rapid ASA (5.5 hours) desensitization procedure. The desensitization procedure was performed before cardiac catheterization in all patients, except for those (n=78, 23.6%) presenting with ST-segment-elevation myocardial infarction who underwent the desensitization after primary percutaneous coronary intervention. Percutaneous coronary intervention was performed in 235 patients (71%) of the overall study population. The desensitization procedure was successful in 315 patients (95.4%) and in all patients with a history of anaphylactic reaction. Among the 15 patients (4.6%) who did not successfully respond to the desensitization protocol, adverse reactions were minor and responded to treatment with corticosteroids and antihistamines. Among patients with successful in-hospital ASA desensitization, 253 patients (80.3%) continued ASA for at least 12 months. Discontinuation of ASA in the 62 patients (19.7%) who had responded to the desensitization protocol was because of medical decision and not because of hypersensitivity reactions. A standard rapid desensitization protocol is safe and effective across a broad spectrum of patients, irrespective of the type of aspirin sensitivity manifestation, with indications to undergo coronary angiography with intent to perform percutaneous coronary intervention. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02848339. © 2017 American Heart Association, Inc.
Li, Jianping; Guo, Jianming; Shang, Erxin; Zhu, Zhenhua; Zhu, Kevin Yue; Li, Shujiao; Zhao, Buchang; Jia, Lifu; Zhao, Jing; Tang, Zhishu; Duan, Jinao
2016-07-15
The drug combination of Danhong injection (DHI) and low-dose aspirin (ASA) was frequently applied for the treatment of cardiovascular and cerebrovascular diseases. Due to the drug interactions, a lot of potential benefits and risks might exist side by side in the course of combination therapy. However, there had been no studies of interaction between DHI and ASA. Metabolomics was a powerful tool to explore endogenous biomarkers and metabolic pathways. In present study, metabolic profiling with ultra-high-performance liquid chromatography coupled to quadrupole time of flight mass spectrometry (UHPLC-QTOF/MS) coupled with multivariate statistical analysis was performed to provide insight into understanding the interaction between DHI and low-dose ASA. Eleven potential biomarkers of three types were identified and seven metabolic pathways were constructed. The results showed that the interaction between DHI and low-dose ASA during synergistic treatment indeed affected some key endogenous biomarkers and metabolic pathways, which could not happen when DHI or low-dose ASA was used alone. The quality and quantity of endogenous metabolite were both influenced by interaction between DHI and low-dose ASA. In details, the amount of flavin mononucleotide, L-2, 4-diaminobutyric acid (DABA) and 4-aminohippuric acid were significantly increased. On the contrary, the amount of 3-methyluridine, 4, 6-dihydroxyquinoline, cortolone-3-glucuronide, and serotonin were significantly decreased. Furthermore, O-phosphotyrosine, 3-methyl-2-butenal, indoxyl sulfate and dolichyl diphosphate were disappeared in urine. As to metabolic pathways, riboflavin metabolism, pentose and glucuronate interconversions, and tryptophan metabolism were all significantly influenced. The emerging alterations of biomarkers and metabolic pathways were associated with a lot of drugs and diseases based on literature researches, which might influence the co-administration of other drugs or the treatments of relevant diseases. Our paper presented some hints to uncover the mechanism of interaction between DHI and low-dose ASA, which would provide some references for application of DHI and low-dose ASA combination. Copyright © 2015 Elsevier B.V. All rights reserved.
Kirkpatrick, Sharon I; Subar, Amy F; Douglass, Deirdre; Zimmerman, Thea P; Thompson, Frances E; Kahle, Lisa L; George, Stephanie M; Dodd, Kevin W; Potischman, Nancy
2014-07-01
The Automated Self-Administered 24-hour Recall (ASA24), a freely available Web-based tool, was developed to enhance the feasibility of collecting high-quality dietary intake data from large samples. The purpose of this study was to assess the criterion validity of ASA24 through a feeding study in which the true intake for 3 meals was known. True intake and plate waste from 3 meals were ascertained for 81 adults by inconspicuously weighing foods and beverages offered at a buffet before and after each participant served him- or herself. Participants were randomly assigned to complete an ASA24 or an interviewer-administered Automated Multiple-Pass Method (AMPM) recall the following day. With the use of linear and Poisson regression analysis, we examined the associations between recall mode and 1) the proportions of items consumed for which a match was reported and that were excluded, 2) the number of intrusions (items reported but not consumed), and 3) differences between energy, nutrient, food group, and portion size estimates based on true and reported intakes. Respondents completing ASA24 reported 80% of items truly consumed compared with 83% in AMPM (P = 0.07). For both ASA24 and AMPM, additions to or ingredients in multicomponent foods and drinks were more frequently omitted than were main foods or drinks. The number of intrusions was higher in ASA24 (P < 0.01). Little evidence of differences by recall mode was found in the gap between true and reported energy, nutrient, and food group intakes or portion sizes. Although the interviewer-administered AMPM performed somewhat better relative to true intakes for matches, exclusions, and intrusions, ASA24 performed well. Given the substantial cost savings that ASA24 offers, it has the potential to make important contributions to research aimed at describing the diets of populations, assessing the effect of interventions on diet, and elucidating diet and health relations. This trial was registered at clinicaltrials.gov as NCT00978406. © 2014 American Society for Nutrition.
Core-Shell Particles as Building Blocks for Systems with High Duality Symmetry
NASA Astrophysics Data System (ADS)
Rahimzadegan, Aso; Rockstuhl, Carsten; Fernandez-Corbaton, Ivan
2018-05-01
Material electromagnetic duality symmetry requires a system to have equal electric and magnetic responses. Intrinsically dual materials that meet the duality conditions at the level of the constitutive relations do not exist in many frequency bands. Nevertheless, discrete objects like metallic helices and homogeneous dielectric spheres can be engineered to approximate the dual behavior. We exploit the extra degrees of freedom of a core-shell dielectric sphere in a particle optimization procedure. The duality symmetry of the resulting particle is more than 1 order of magnitude better than previously reported nonmagnetic objects. We use T -matrix-based multiscattering techniques to show that the improvement is transferred onto the duality symmetry of composite objects when the core-shell particle is used as a building block instead of homogeneous spheres. These results are relevant for the fashioning of systems with high duality symmetry, which are required for some technologically important effects.
NASA Astrophysics Data System (ADS)
Nguyen, K. L.; Merchiers, O.; Chapuis, P.-O.
2017-11-01
We compute the near-field radiative heat transfer between a hot AFM tip and a cold substrate. This contribution to the tip-sample heat transfer in Scanning Thermal Microscopy is often overlooked, despite its leading role when the tip is out of contact. For dielectrics, we provide power levels exchanged as a function of the tip-sample distance in vacuum and spatial maps of the heat flux deposited into the sample which indicate the near-contact spatial resolution. The results are compared to analytical expressions of the Proximity Flux Approximation. The numerical results are obtained by means of the Boundary Element Method (BEM) implemented in the SCUFF-EM software, and require first a thorough convergence analysis of the progressive implementation of this method to the thermal emission by a sphere, the radiative transfer between two spheres, and the radiative exchange between a sphere and a finite substrate.
NASA Astrophysics Data System (ADS)
Mohamad Alosfur, Firas K.; Ridha, Noor J.; Hafizuddin Haji Jumali, Mohammad; Radiman, S.
2018-04-01
Mesoporous TiO2 hollow spherical nanostructures with high surface areas were successfully prepared using a microwave method. The prepared hollow spheres had a size range between 200 and 500 nm. The spheres consisted of numerous smaller TiO2 nanoparticles with an average diameter of 8 nm. The particles had an essentially mesoporous structure, with a pore size in the range of 2-50 nm. The results confirmed that the synthesised of anatase TiO2 nanoparticles with specific surface area approximately 172.3 m2 g-1. The effect of ultraviolet and visible light irradiation and catalyst dosage on the TiO2 photocatalytic activity was studied by measuring the degradation rate of methylene blue. The maximum dye degradation performances with low catalyst loading (30 mg) were 99% and 63.4% using the same duration of ultraviolet and visible light irradiation, respectively (120 min).
Capillary Pressure of a Liquid Between Uniform Spheres Arranged in a Square-Packed Layer
NASA Technical Reports Server (NTRS)
Alexader, J. Iwan D.; Slobozhanin, Lev A.; Collicott, Steven H.
2004-01-01
The capillary pressure in the pores defined by equidimensional close-packed spheres is analyzed numerically. In the absence of gravity the menisci shapes are constructed using Surface Evolver code. This permits calculation the free surface mean curvature and hence the capillary pressure. The dependences of capillary pressure on the liquid volume constructed here for a set of contact angles allow one to determine the evolution of basic capillary characteristics under quasi-static infiltration and drainage. The maximum pressure difference between liquid and gas required for a meniscus passing through a pore is calculated and compared with that for hexagonal packing and with approximate solution given by Mason and Morrow [l]. The lower and upper critical liquid volumes that determine the stability limits for the equilibrium capillary liquid in contact with square packed array of spheres are tabulated for a set of contact angles.
NASA Technical Reports Server (NTRS)
Morris, P. A.; Wentworth, Susan J.; Thomas-Keprta, Kathie L.; Allen, Carlton C.; Schwandt, Craig S.; McKay, David S.; Westall, Frances; Bell, Mary Sue; Gibson, Everett K.
2000-01-01
Iron-bearing spherules in Archean Warrawoona rocks are composed of hematite and goethite. They are clearly syngenetic with the rock but their origin, whether biological or abiogenic, is not yet known.
Sliding friction of nanocomposite WC1-x/C coatings: transfer film and its influence on tribology.
Liu, Y; Gubisch, M; Spiess, L; Schaefer, J A
2009-06-01
The transfer film on steel spheres formed in reciprocating sliding against nanocomposite coatings based on nanocrystalline WC1-x in amorphous carbon matrix is characterized and correlated with the tribological properties measured by a precision microtribometer. With the presence of transfer film, a coefficient of friction approximately 0.13 and a depth wear rate approximately 0.35 x 10(-10) m/N.Pass were obtained. The central zone of the transfer film covering approximately 25% of the Hertz contact area is intact while cracks and wear debris are found in the vast peripheral area. It is also heavily oxidized due to the absence of carbon, which is located at the peripherals and acts as lubricants. We propose that the oxidation of WC and adhesion of the oxides to the surface of sphere is the main mechanism for the buildup of the transfer films. With the thickening of the film, the internal stress increases. Under the shear stress, spalling and cracking of the transfer film take place. The overall tribological performance of the coatings is therefore a competing process of buildup and spalling of transfer films.
Discovery of 11 ASAS-SN Supernovae
NASA Astrophysics Data System (ADS)
Brimacombe, J.; Cacella, P.; Stone, G.; Fernandez, J. M.; Vallely, P.; Stanek, K. Z.; Kochanek, C. S.; Brown, J. S.; Shields, J.; Thompson, T. A.; Shappee, B. J.; Holoien, T. W.-S.; Prieto, J. L.; Bersier, D.; Dong, Subo; Bose, S.; Chen, Ping; Stritzinger, M.; Holmbo, S.; Nicholls, B.; Post, R. S.
2018-05-01
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014), using data from 14-cm telescopes in Hawaii, Texas, South Africa, and Chile, we discovered several new transient sources.
ASA24® Researcher Instructions
Step-by-step instructions, including screen shots, for setting-up a study to collect 24-hour recalls or food records are available for download to help researchers, clinicians, and educators use the ASA24 system.
Littleton, Heather L; Grills, Amie E; Drum, Katherine B
2014-01-01
Although having a sexual victimization history is associated with engaging in sexual risk behavior, the mechanisms whereby sexual victimization increases risk behavior are unclear. This study examined use of sex as an affect regulation strategy as a mediator of the relationship between depressive symptoms and sexual risk behavior among 1,616 sexually active college women as well as examined having a history of child sexual abuse (CSA), adolescent/adult sexual assault (ASA), or both (CSA/ASA) as moderators. Results supported the mediated model as well as moderated mediation, where depressive symptoms were more strongly associated with use of sex as an affect regulation strategy among ASA victims, and sex as an affect regulation strategy was more strongly related to sexual risk behavior for CSA/ASA victims.
Guez, S; Gualde, N; Bezian, J H; Cabanieu, G
1992-01-01
Aspirine-sensitive asthma (ASA) is a disease defined only by clinical criteria. It is an intrinsic asthma related to a hypersensitivity to aspirin. The illness is linked to abnormalities in platelet and macrophage arachidonic acid metabolism. We assessed in vitro the platelet chemoluminescence (CL) and lymphocyte proliferative response of ASA patients. We observed that platelets from patients and control do not generate any CL in the presence of aspirin. Concerning the proliferative response of lymphocytes, the in vitro effect of aspirin depends upon the origin of the lymphocytes tested. Thus aspirin clearly enhances the proliferative response of lymphocytes from normal subjects but diminishes the thymidine uptake by lymphocytes from ASA patients. This discrepancy in the in vitro response of lymphocytes from normal subjects and patients might be useful for in vitro diagnosis of ASA.
Fiarresga, António; Cacela, Duarte; Galrinho, Ana; Ramos, Ruben; de Sousa, Lídia; Bernardes, Luís; Patrício, Lino; Cruz Ferreira, Rui
2014-01-01
We describe our center's initial experience with alcohol septal ablation (ASA) for the treatment of obstructive hypertrophic cardiomyopathy. The procedure, its indications, results and clinical outcomes will be addressed, as will its current position compared to surgical myectomy. To assess the results of ASA in all patients treated in the first four years of activity at our center. We retrospectively studied all consecutive and unselected patients treated by ASA between January 2009 and February 2013. In the first four years of experience 40 patients were treated in our center. In three patients (7.5%) the intervention was repeated. Procedural success was 84%. Minor complications occurred in 7.5%. Two patients received a permanent pacemaker for atrioventricular block (6% of those without previous pacemaker). The major complication rate was 5%. There were no in-hospital deaths; during clinical follow-up (22 ± 14 months) cardiovascular mortality was 2.5% and overall mortality was 5%. The results presented reflect the initial experience of our center with ASA. The success rate was high and in line with published results, but with room to improve with better patient selection. ASA was shown to be safe, with a low complication rate and no procedure-related mortality. Our experience confirms ASA as a percutaneous alternative to myectomy for the treatment of symptomatic patients with obstructive hypertrophic cardiomyopathy refractory to medical treatment. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.
Assessment of Water Quality in Asa River (Nigeria) and Its Indigenous Clarias gariepinus Fish
Kolawole, Olatunji M.; Ajayi, Kolawole T.; Olayemi, Albert B.; Okoh, Anthony I.
2011-01-01
Water is a valued natural resource for the existence of all living organisms. Management of the quality of this precious resource is, therefore, of special importance. In this study river water samples were collected and analysed for physicochemical and bacteriological evaluation of pollution in the Unity Road stream segment of Asa River in Ilorin, Nigeria. Juvenile samples of Clarias gariepinus fish were also collected from the experimental Asa River and from the control Asa Dam water and were analysed for comparative histological investigations and bacterial density in the liver and intestine in order to evaluate the impact of pollution on the aquatic biota. The water pH was found to range from 6.32 to 6.43 with a mean temperature range of 24.3 to 25.8 °C. Other physicochemical parameters monitored including total suspended solids, total dissolved solids, biochemical oxygen demand and chemical oxygen demand values exceeded the recommended level for surface water quality. Results of bacteriological analyses including total heterotrophic count, total coliform and thermotolerant coliform counts revealed a high level of faecal pollution of the river. Histological investigations revealed no significant alterations in tissue structure, but a notable comparative distinction of higher bacterial density in the intestine and liver tissues of Clarias gariepinus from Asa River than in those collected from the control. It was inferred that the downstream Asa River is polluted and its aquatic biota is bacteriologically contaminated and unsafe for human and animal consumption. PMID:22163210
Bhat, Pragathi Raghavendra; Acharya, Anirudh Balakrishna; Thakur, Srinath Lakshman
2016-01-01
The palatal approach of anterior superior alveolar (P-ASA) using WAND injection was reported to effectively provide a profound bilateral maxillary anesthesia of the soft tissue of anterior one-third of the palate and facial gingivae extending from canine to canine which lasted for more than an hour thus making it ideal for scaling root planing and minor periodontal procedures in the anterior maxilla. Our study suggests that the conventional P-ASA injection is of very short duration and the extent of anesthesia was not profound and consistent. This has not been reported earlier in the literature. Thirty-five cases (20 males and 15 females), who underwent scaling, root planing and minor periodontal surgical procedures such as abscess drainage, gingivectomy, and frenectomy in the maxillary anterior region in the age range of 19-45 years was assessed for the efficacy of the P-ASA injection. After the administration of the P-ASA injection, the subjective and the objective symptoms were used to evaluate the extent and duration of the anesthesia at 10, 15, and 20 min. This study suggests that the conventional P-ASA injection technique does not provide anesthesia for more than 20 min. Wilcoxon matched pairs test was used to compare the effect of anesthesia at the different time intervals and the results were found to be statistically significant ( P < 0.05). The conventional P-ASA injection technique is of very short duration and does not demonstrate effectiveness in periodontal surgery of the anterior maxilla.
Effects of acetyl salycilic acid and ibuprofen in chronic liver damage induced by CCl4.
Chávez, Enrique; Castro-Sánchez, Luis; Shibayama, Mineko; Tsutsumi, Victor; Pérez Salazar, Eduardo; Moreno, Mario G; Muriel, Pablo
2012-01-01
Non-steroidal anti-inflammatory drugs (NSAIDs) are drugs used primarily to treat inflammation, pain and fever. Their main mechanism of action is cyclooxygenase (COX) inhibition, and this enzyme has been linked to hepatotoxicity. The association of COX and liver injury has been, in part, due to the presence of COX-2 isoform in damaged liver and the possible induction of this enzyme by profibrotic molecules like Transforming Growth Factor-β (TGF-β). The aim of this work was to evaluate the effects of two of the most used NSAIDs, acetyl salicylic acid (ASA) and ibuprofen (IBP), on experimental liver fibrosis. We formed experimental groups of rats including vehicle and drug controls, damage induced by chronic CCl4 (0.4 g kg(-1) , i.p., three times per week, for 8 weeks) administration, and CCl4 plus ASA (100 mg kg(-1) , p.o., daily) or IBP (30 mg kg(-1) , p.o., daily). Both drugs showed important antifibrotic properties. They inhibited COX-2 activity, prevented oxidative stress measured as lipid peroxidation and glutathione content, and ASA inhibited partially and IBP totally increased TGF-β expression and collagen content. ASA and IBP prevented translocation of NFκB to the nucleus and, interestingly, ASA induced MMP-2 and MMP-13 whereas IBP induced MMP-2, MMP-9 and MMP-13. As a whole, these effects explain the beneficial effects of ASA and IBP on experimental liver fibrosis. Copyright © 2011 John Wiley & Sons, Ltd.
An Energy Aware Adaptive Sampling Algorithm for Energy Harvesting WSN with Energy Hungry Sensors.
Srbinovski, Bruno; Magno, Michele; Edwards-Murphy, Fiona; Pakrashi, Vikram; Popovici, Emanuel
2016-03-28
Wireless sensor nodes have a limited power budget, though they are often expected to be functional in the field once deployed for extended periods of time. Therefore, minimization of energy consumption and energy harvesting technology in Wireless Sensor Networks (WSN) are key tools for maximizing network lifetime, and achieving self-sustainability. This paper proposes an energy aware Adaptive Sampling Algorithm (ASA) for WSN with power hungry sensors and harvesting capabilities, an energy management technique that can be implemented on any WSN platform with enough processing power to execute the proposed algorithm. An existing state-of-the-art ASA developed for wireless sensor networks with power hungry sensors is optimized and enhanced to adapt the sampling frequency according to the available energy of the node. The proposed algorithm is evaluated using two in-field testbeds that are supplied by two different energy harvesting sources (solar and wind). Simulation and comparison between the state-of-the-art ASA and the proposed energy aware ASA (EASA) in terms of energy durability are carried out using in-field measured harvested energy (using both wind and solar sources) and power hungry sensors (ultrasonic wind sensor and gas sensors). The simulation results demonstrate that using ASA in combination with an energy aware function on the nodes can drastically increase the lifetime of a WSN node and enable self-sustainability. In fact, the proposed EASA in conjunction with energy harvesting capability can lead towards perpetual WSN operation and significantly outperform the state-of-the-art ASA.
Wu, Di; Xu, Jiao; Song, Erbao; Tang, Shu; Zhang, Xiaohui; Kemper, N; Hartung, J; Bao, Endong
2015-07-01
We investigated whether acetyl salicylic acid (ASA) protects chicken myocardial cells from heat stress-mediated damage in vivo and whether the induction of Hsp27 expression is connected with this function. Pathological changes, damage-related enzyme levels, and Hsp27 expression were studied in chickens following heat stress (40 ± 1 °C for 0, 1, 2, 3, 5, 7, 10, 15, or 24 h, respectively) with or without ASA administration (1 mg/kg BW, 2 h prior). Appearance of pathological lesions such as degenerations and karyopyknosis as well as the myocardial damage-related enzyme activation indicated that heat stress causes considerable injury to the myocardial cells in vivo. Myocardial cell injury was most serious in chickens exposed to heat stress without prior ASA administration; meanwhile, ASA pretreatment acted protective function against high temperature-induced injury. Hsp27 expression was induced under all experimental conditions but was one-fold higher in the ASA-pretreated animals (0.3138 ± 0.0340 ng/mL) than in untreated animals (0.1437 ± 0.0476 ng/mL) 1 h after heat stress exposure, and such an increase was sustained over the length of the experiment. Our findings indicate that pretreatment with ASA protects chicken myocardial cells from acute heat stress in vivo with almost no obvious side effects, and this protection may involve an enhancement of Hsp27 expression. However, the detailed mechanisms underlying this effect require further investigation.
Optimizing clinical use of mesalazine (5-aminosalicylic acid) in inflammatory bowel disease
Williams, Chadwick; Panaccione, Remo; Ghosh, Subrata; Rioux, Kevin
2011-01-01
Mesalazine [5-aminosalicylic acid (5-ASA)] has been used for over 30 years in the treatment of inflammatory bowel disease (IBD). It is a highly effective, safe, and well-tolerated drug for treatment of mild to moderate ulcerative colitis, which represents most patients with this disease. Recent studies of patient adherence to 5-ASA therapies in ulcerative colitis have highlighted the need for regimens that enable long-term compliance to significantly reduce the risk of troublesome and debilitating flares in the short term, and possibly colon cancer in the long term. Indeed, much of the recent innovation in clinical use of 5-ASA in colitis has come from studies of novel delivery mechanisms and simplified oral dosing schedules. These studies have provided much needed clarity on essential matters such as starting dose, dose escalation, and efficacy in terms of the ideal clinical endpoint - mucosal healing. Various manufacturers are re-evaluating their products to determine the safety and efficacy of such dosing regimens. Although once widely employed in the treatment of Crohn’s disease (CD), the accumulated body of evidence now suggests that there is a much more limited role for 5-ASA in this particular form of inflammatory bowel disease. Recent 5-ASA randomized-controlled trials, comparative studies, and outcomes research have led to refined treatment strategies and awareness for practitioners to better inform, engage and facilitate patients in optimal use of 5-ASA in inflammatory bowel disease. PMID:21765868
Lei, Chang; Yan, Bo; Chen, Tao; Xiao, Xian-Ming
2018-05-19
To comprehensively reuse the leaching residue obtained from lead-zinc tailings, an active silicon adsorbent (ASA) was prepared from leaching residue and studied as an adsorbent for copper(II), lead(II), zinc(II), and cadmium(II) in this paper. The ASA was prepared by roasting the leaching residue with either a Na 2 CO 3 /residue ratio of 0.6:1 at 700 °C for 1 h or a CaCO 3 /residue ratio of 0.8:1 at 800 °C for 1 h. Under these conditions, the available SiO 2 content of the ASA was more than 20%. The adsorption behaviors of the metal ions onto the ASA were investigated and the Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were used to analyze the adsorption isotherm. The result showed that the maximum adsorption capacities of copper(II), lead(II), cadmium(II), and zinc(II) calculated by the Langmuir model were 3.40, 2.83, 0.66, and 0.62 mmol g -1 , respectively. The FT-IR spectra of the ASA and the mean free adsorption energies indicated that ion exchange was the mechanism of copper(II), lead(II), and cadmium(II) adsorption and that chemical reaction was the mechanism of zinc(II) adsorption. These results provide a method for reusing the leaching residue obtained from lead-zinc tailings and show that the ASA is an effective adsorbent for heavy metal pollution remediation.
Silk Nanospheres and Microspheres from Silk/PVA Blend Films for Drug Delivery
Wang, Xiaoqin; Yucel, Tuna; Lu, Qiang; Hu, Xiao; Kaplan, David L.
2009-01-01
Silk fibroin protein-based micro- and nanospheres provide new options for drug delivery due to their biocompatibility, biodegradability and their tunable drug loading and release properties. In the present study, we report a new aqueous-based preparation method for silk spheres with controllable sphere size and shape. The preparation was based on phase separation between silk fibroin and polyvinyl alcohol (PVA) at a weight ratio of 1/1 and 1/4. Water-insoluble silk spheres were easily obtained from the blend in a three step process: (1) air-drying the blend solution into a film, (2) film dissolution in water and (3) removal of residual PVA by subsequent centrifugation. In both cases, the spheres had approximately 30% beta-sheet content and less than 5% residual PVA. Spindle-shaped silk particles, as opposed to the spherical particles formed above, were obtained by stretching the blend films before dissolving in water. Compared to the 1/1 ratio sample, the silk spheres prepared from the 1/4 ratio sample showed a more homogeneous size distribution ranging from 300 nm up to 20 μm. Further studies showed that sphere size and polydispersity could be controlled either by changing the concentration of silk and PVA or by applying ultrasonication on the blend solution. Drug loading was achieved by mixing model drugs in the original silk solution. The distribution and loading efficiency of the drug molecules in silk spheres depended on their hydrophobicity and charge, resulting in different drug release profiles. The entire fabrication procedure could be completed within one day. The only chemical used in the preparation except water was PVA, an FDA-approved ingredient in drug formulations. Silk micro- and nanospheres reported have potential as drug delivery carriers in a variety of biomedical applications. PMID:19945157
Hydration entropy change from the hard sphere model.
Graziano, Giuseppe; Lee, Byungkook
2002-12-10
The gas to liquid transfer entropy change for a pure non-polar liquid can be calculated quite accurately using a hard sphere model that obeys the Carnahan-Starling equation of state. The same procedure fails to produce a reasonable value for hydrogen bonding liquids such as water, methanol and ethanol. However, the size of the molecules increases when the hydrogen bonds are turned off to produce the hard sphere system and the volume packing density rises. We show here that the hard sphere system that has this increased packing density reproduces the experimental transfer entropy values rather well. The gas to water transfer entropy values for small non-polar hydrocarbons is also not reproduced by a hard sphere model, whether one uses the normal (2.8 A diameter) or the increased (3.2 A) size for water. At least part of the reason that the hard sphere model with 2.8 A size water produces too small entropy change is that the size of water is too small for a system without hydrogen bonds. The reason that the 3.2 A model also produces too small entropy values is that this is an overly crowded system and that the free volume introduced in the system by the addition of a solute molecule produces too much of a relief to this crowding. A hard sphere model, in which the free volume increase is limited by requiring that the average surface-to-surface distance between the solute and water molecules is the same as that between the increased-size water molecules, does approximately reproduce the experimental hydration entropy values. Copyright 2002 Elsevier Science B.V.
Abdelhamid, Rehab F; Obara, Yuji; Kohzuma, Takamitsu
2008-01-01
Several blue copper proteins are known to change the active site structure at alkaline pH (alkaline transition). Spectroscopic studies of Met16Phe, Met16Tyr, Met16Trp, and Met16Val pseudoazurin variants were performed to investigate the second sphere role through alkaline transition. The visible electronic absorption and resonance Raman spectra of Met16Phe, Met16Tyr, and Met16Trp variants showed the increasing of axial component at pH approximately 11 like wild-type PAz. The visible electronic absorption and far-UV CD spectra of Met16Val demonstrated that the destabilization of the protein structure was triggered at pH>11. Resonance Raman (RR) spectra of PAz showed that the intensity-weighted averaged Cu-S(Cys) stretching frequency was shifted to higher frequency region at pH approximately 11. The higher frequency shift of Cu-S(Cys) bond is implied the stronger Cu-S(Cys) bond at alkaline transition pH approximately 11. The visible electronic absorption and far-UV CD spectra of Met16X PAz revealed that the Met16Val variant is denatured at pH>11, but Met16Phe, Met16Tyr, and Met16Trp mutant proteins are not denatured even at pH>11. These observations suggest that Met16 is important to maintain the protein structure through the possible weak interaction between methionine -SCH3 part and coordinated histidine imidazole moiety. The introduction of pi-pi interaction in the second coordination sphere may be contributed to the enhancement of protein structure stability.
NASA Astrophysics Data System (ADS)
Chiarot, C. B.; Siewerdsen, J. H.; Haycocks, T.; Moseley, D. J.; Jaffray, D. A.
2005-11-01
Development, characterization, and quality assurance of advanced x-ray imaging technologies require phantoms that are quantitative and well suited to such modalities. This note reports on the design, construction, and use of an innovative phantom developed for advanced imaging technologies (e.g., multi-detector CT and the numerous applications of flat-panel detectors in dual-energy imaging, tomosynthesis, and cone-beam CT) in diagnostic and image-guided procedures. The design addresses shortcomings of existing phantoms by incorporating criteria satisfied by no other single phantom: (1) inserts are fully 3D—spherically symmetric rather than cylindrical; (2) modules are quantitative, presenting objects of known size and contrast for quality assurance and image quality investigation; (3) features are incorporated in ideal and semi-realistic (anthropomorphic) contexts; and (4) the phantom allows devices to be inserted and manipulated in an accessible module (right lung). The phantom consists of five primary modules: (1) head, featuring contrast-detail spheres approximate to brain lesions; (2) left lung, featuring contrast-detail spheres approximate to lung modules; (3) right lung, an accessible hull in which devices may be placed and manipulated; (4) liver, featuring conrast-detail spheres approximate to metastases; and (5) abdomen/pelvis, featuring simulated kidneys, colon, rectum, bladder, and prostate. The phantom represents a two-fold evolution in design philosophy—from 2D (cylindrically symmetric) to fully 3D, and from exclusively qualitative or quantitative to a design accommodating quantitative study within an anatomical context. It has proven a valuable tool in investigations throughout our institution, including low-dose CT, dual-energy radiography, and cone-beam CT for image-guided radiation therapy and surgery.
Light qualities and dose influence ascorbate pool size in detached oat leaves.
Mastropasqua, Linda; Borraccino, Giuseppe; Bianco, Laura; Paciolla, Costantino
2012-02-01
In this work, we studied the mechanism of light influence on AsA pool size in Avena sativa L. under the effects of low intensity light at different wavelengths. Exposure to low intensity light of oat leaf segments incubated in water or in l-galactono-1,4-lactone (GL), resulted in an increase in AsA content compared with the dark control. This increase was due to modulation of l-galactono-1,4-lactone dehydrogenase (GLDH; EC 1.3.2.3) light-dependent activity and was dependent on the size of the endogenous GL pool. Both blue and red light were effective in increasing AsA, and this increase depended on both exposure time and light intensity. Protein biosynthesis, photosynthesis and calcium were involved in controlling the level of light-dependent AsA. We suggest that multiple checkpoints correlated to the presence of light underlie the ascorbate pool size. The presence of a light-activated switch for the maintenance of an adequate AsA level seems to be necessary for the various tasks of scavenging reactive oxygen species, in response to the dark-light cycle which plants experience under natural conditions. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Nam, Joon; Kim, Wooseong; Lee, Sunyoung; Jeong, Seongkeun; Yoo, Jin-Wook; Kim, Min-Soo; Jung, Yunjin
2016-01-01
Local anesthetics have beneficial effects on colitis. Dextran-5-(4-ethoxycarbonylphenylazo)salicylic acid ester (Dex-5-ESA), designed as a polymeric colon-specific prodrug liberating 5-ASA and benzocaine in the large intestine, was prepared and its therapeutic activity against colitis was evaluated using a TNBS-induced rat colitis model. Dex-5-ESA liberated 5-ASA and benzocaine in the cecal contents while (bio)chemically stable in the small intestinal contents and mucosa. Oral administration of Dex-5-ESA (equivalent to 10 mg 5-ASA/kg, twice a day) alleviated colonic injury and reduced MPO activity in the inflamed colon. In parallel, pro-inflammatory mediators, COX-2, iNOS and CINC-3, elevated by TNBS-induced colitis, were substantially diminished in the inflamed colon. Dex-5-ESA was much more effective for the treatment of colitis than 5-(4-ethoxycarbonylphenylazo)salicylic acid (5-ESA) that may not deliver benzocaine to the large intestine. Our data suggest that Dex-5-ESA is a polymeric colon-specific prodrug, liberating 5-ASA and benzocaine in the target site (large intestine), probably exerting anti-colitic effects by combined action of 5-ASA and benzocaine.
An, Fuqiang; Gao, Baojiao; Dai, Xin; Wang, Min; Wang, Xiaohua
2011-09-15
In this study, 5-aminosalicylic acid was successfully grafted onto the poly(glycidyl methacrylate) (PGMA) macromolecular chains of PGMA/SiO(2) to obtain a novel adsorbent designated as ASA-PGMA/SiO(2). The adsorption properties of ASA-PGMA/SiO(2) for heavy metal ions were studied through batch and column methods. The experimental results showed that ASA-PGMA/SiO(2) possesses strong chelating adsorption ability for heavy metal ions, and its adsorption capacity for Cu(2+), Cd(2+), Zn(2+), and Pb(2+) reaches 0.42, 0.40, 0.35, and 0.31 mmol g(-1), respectively. In addition, pH has a great influence on the adsorption capacity in the studied pH range. The adsorption isotherm data greatly obey the Langmuir and Freundlich model. The desorption of metal ions from ASA-PGMA/SiO(2) is effective using 0.1 mol l(-1) of hydrochloric acid solution as eluent. Consecutive adsorption-desorption experiments showed that ASA-PGMA/SiO(2) could be reused almost without any loss in the adsorption capacity. Copyright © 2011 Elsevier B.V. All rights reserved.
Manguso, F; Balzano, A
2007-07-01
Beclomethasone dipropionate (BDP) is a second-generation steroid with topical effects and minimal systemic activity for patients with ulcerative colitis (UC). To review all available literature to assess the efficacy of enema/foam BDP compared with enema/foam 5-aminosalicylic acid (5-ASA) in the control of left-sided mild-moderate UC. We selected randomized controlled trials of enema/foam BDP compared with enema/foam 5-ASA treatment in patients with UC. Two reviewers assessed trial quality and extracted data independently. Four trials involving 428 UC patients, 209 treated with 5-ASA (1-4 g o.d.) and 219 with BDP (3 mg o.d.), were included. Intention-to-treat analysis showed that 5-ASA induced improvement/remission of UC in 146 (69.9%) patients, while BDP in 143 (65.3%). The test for heterogeneity (Cochran Q) was not significant and Mantel-Haenszel pooled estimate of odds ratio was 1.23 (95% CI = 0.82-1.85). The results did not change when analysis was performed on a per-protocol basis. The randomized controlled trials identified in this review showed that rectal BDP has equal effect as 5-ASA to control symptoms in UC.
Biowaiver monograph for immediate-release solid oral dosage forms: acetylsalicylic acid.
Dressman, Jennifer B; Nair, Anita; Abrahamsson, Bertil; Barends, Dirk M; Groot, D W; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Zimmer, Markus
2012-08-01
A biowaiver monograph for acetylsalicylic acid (ASA) is presented. Literature and experimental data indicate that ASA is a highly soluble and highly permeable drug, leading to assignment of this active pharmaceutical ingredient (API) to Class I of the Biopharmaceutics Classification System (BCS). Limited bioequivalence (BE) studies reported in the literature indicate that products that have been tested are bioequivalent. Most of the excipients used in products with a marketing authorization in Europe are not considered to have an impact on gastrointestinal motility or permeability. Furthermore, ASA has a wide therapeutic index. Thus, the risks to the patient that might occur if a nonbioequivalent product were to be incorrectly deemed bioequivalent according to the biowaiver procedure appear to be minimal. As a result, the BCS-based biowaiver procedure can be recommended for approval of new formulations of solid oral dosage forms containing ASA as the only API, including both multisource and reformulated products, under the following conditions: (1) excipients are chosen from those used in ASA products already registered in International Conference on Harmonization and associated countries and (2) the dissolution profiles of the test and the comparator products comply with the BE guidance. Copyright © 2012 Wiley Periodicals, Inc.
Metal-rich or misclassified? The case of four RR Lyrae stars
NASA Astrophysics Data System (ADS)
Molnar, L.; Juhasz, A. L.; Plachy, E.; Szabo, R.
2016-06-01
We analysed the light curve of four, apparently extremely metal-rich fundamenta-mode RR Lyrae stars. We identified two stars, MT Tel and ASAS J091803-3022.6 as RRc (first-overtone) pulsators that were misclassified as RRab ones in the ASAS survey. In the case of the other two stars, V397 Gem and ASAS J075127-4136.3, we could not decide conclusively, as they are outliers in the period-Fourier-coefficient space from the loci of both classes, but their photometric metallicities also favour the RRc classification.
All Source Analysis System (ASAS): Migration from VAX to Alpha AXP computer systems
NASA Technical Reports Server (NTRS)
Sjoholm-Sierchio, Michael J.; Friedman, Steven Z. (Editor)
1994-01-01
The Jet Propulsion Laboratory's (JPL's) experience migrating existing VAX applications to Digital Equipment Corporation's new Alpha AXP processor is covered. The rapid development approach used during the 10-month period required to migrate the All Source Analysis System (ASAS), 1.5 million lines of FORTRAN, C, and Ada code, is also covered. ASAS, an automated tactical intelligence system, was developed by the Jet Propulsion Laboratory for the U. S. Army. Other benefits achieved as a result of the significant performance improvements provided by Alpha AXP platform are also described.
Analytical expressions for the correlation function of a hard sphere dimer fluid
NASA Astrophysics Data System (ADS)
Kim, Soonho; Chang, Jaeeon; Kim, Hwayong
A closed form expression is given for the correlation function of a hard sphere dimer fluid. A set of integral equations is obtained from Wertheim's multidensity Ornstein-Zernike integral equation theory with Percus-Yevick approximation. Applying the Laplace transformation method to the integral equations and then solving the resulting equations algebraically, the Laplace transforms of the individual correlation functions are obtained. By the inverse Laplace transformation, the radial distribution function (RDF) is obtained in closed form out to 3D (D is the segment diameter). The analytical expression for the RDF of the hard dimer should be useful in developing the perturbation theory of dimer fluids.
Analytical expression for the correlation function of a hard sphere chain fluid
NASA Astrophysics Data System (ADS)
Chang, Jaeeon; Kim, Hwayong
A closed form expression is given for the correlation function of flexible hard sphere chain fluid. A set of integral equations obtained from Wertheim's multidensity Ornstein-Zernike integral equation theory with the polymer Percus-Yevick ideal chain approximation is considered. Applying the Laplace transformation method to the integral equations and then solving the resulting equations algebraically, the Laplace transforms of individual correlation functions are obtained. By inverse Laplace transformation the inter- and intramolecular radial distribution functions (RDFs) are obtained in closed forms up to 3D(D is segment diameter). These analytical expressions for the RDFs would be useful in developing the perturbation theory of chain fluids.
Light absorption by coated nano-sized carbonaceous particles
NASA Astrophysics Data System (ADS)
Gangl, Martin; Kocifaj, Miroslav; Videen, Gorden; Horvath, Helmuth
The optical properties of strongly absorbing soot particles coated by transparent material are investigated experimentally and described by several modeling approaches. Soot is produced by spark discharge and passed through a Sinclair-La Mer generator where non-absorbing carnauba wax is condensed onto it to obtain internal soot-wax mixtures in a controlled way. Measurements of the extinction and volume scattering coefficient show an amplification of absorption by a factor of approximately 1.8. This behavior was described by different approaches of internally mixed materials for the modal diameters of the measured size distributions: concentric-sphere model, effective medium approximations and heterogeneous ellipsoids. The concentric-sphere model describes the absorption increase quantitatively; and hence, it is chosen to be applied to the entire particle population in the size distribution. The growth of the soot particles by condensing wax is described by a simplified growth model to estimate the different contributions of several soot particle diameters to the overall absorption cross-section.
Time-resolved polarization imaging by pump-probe (stimulated emission) fluorescence microscopy.
Buehler, C; Dong, C Y; So, P T; French, T; Gratton, E
2000-01-01
We report the application of pump-probe fluorescence microscopy in time-resolved polarization imaging. We derived the equations governing the pump-probe stimulated emission process and characterized the pump and probe laser power levels for signal saturation. Our emphasis is to use this novel methodology to image polarization properties of fluorophores across entire cells. As a feasibility study, we imaged a 15-microm orange latex sphere and found that there is depolarization that is possibly due to energy transfer among fluorescent molecules inside the sphere. We also imaged a mouse fibroblast labeled with CellTracker Orange CMTMR (5-(and-6)-(((4-chloromethyl)benzoyl)amino)tetramethyl-rhodamine). We observed that Orange CMTMR complexed with gluthathione rotates fast, indicating the relatively low fluid-phase viscosity of the cytoplasmic microenvironment as seen by Orange CMTMR. The measured rotational correlation time ranged from approximately 30 to approximately 150 ps. This work demonstrates the effectiveness of stimulated emission measurements in acquiring high-resolution, time-resolved polarization information across the entire cell. PMID:10866979
The isotropic-nematic phase transition of tangent hard-sphere chain fluids—Pure components
NASA Astrophysics Data System (ADS)
van Westen, Thijs; Oyarzún, Bernardo; Vlugt, Thijs J. H.; Gross, Joachim
2013-07-01
An extension of Onsager's second virial theory is developed to describe the isotropic-nematic phase transition of tangent hard-sphere chain fluids. Flexibility is introduced by the rod-coil model. The effect of chain-flexibility on the second virial coefficient is described using an accurate, analytical approximation for the orientation-dependent pair-excluded volume. The use of this approximation allows for an analytical treatment of intramolecular flexibility by using a single pure-component parameter. Two approaches to approximate the effect of the higher virial coefficients are considered, i.e., the Vega-Lago rescaling and Scaled Particle Theory (SPT). The Onsager trial function is employed to describe the orientational distribution function. Theoretical predictions for the equation of state and orientational order parameter are tested against the results from Monte Carlo (MC) simulations. For linear chains of length 9 and longer, theoretical results are in excellent agreement with MC data. For smaller chain lengths, small errors introduced by the approximation of the higher virial coefficients become apparent, leading to a small under- and overestimation of the pressure and density difference at the phase transition, respectively. For rod-coil fluids of reasonable rigidity, a quantitative comparison between theory and MC simulations is obtained. For more flexible chains, however, both the Vega-Lago rescaling and SPT lead to a small underestimation of the location of the phase transition.
Castro, Juan C; Maddox, J Dylan; Cobos, Marianela; Requena, David; Zimic, Mirko; Bombarely, Aureliano; Imán, Sixto A; Cerdeira, Luis A; Medina, Andersson E
2015-11-24
Myrciaria dubia is an Amazonian fruit shrub that produces numerous bioactive phytochemicals, but is best known by its high L-ascorbic acid (AsA) content in fruits. Pronounced variation in AsA content has been observed both within and among individuals, but the genetic factors responsible for this variation are largely unknown. The goals of this research, therefore, were to assemble, characterize, and annotate the fruit transcriptome of M. dubia in order to reconstruct metabolic pathways and determine if multiple pathways contribute to AsA biosynthesis. In total 24,551,882 high-quality sequence reads were de novo assembled into 70,048 unigenes (mean length = 1150 bp, N50 = 1775 bp). Assembled sequences were annotated using BLASTX against public databases such as TAIR, GR-protein, FB, MGI, RGD, ZFIN, SGN, WB, TIGR_CMR, and JCVI-CMR with 75.2 % of unigenes having annotations. Of the three core GO annotation categories, biological processes comprised 53.6 % of the total assigned annotations, whereas cellular components and molecular functions comprised 23.3 and 23.1 %, respectively. Based on the KEGG pathway assignment of the functionally annotated transcripts, five metabolic pathways for AsA biosynthesis were identified: animal-like pathway, myo-inositol pathway, L-gulose pathway, D-mannose/L-galactose pathway, and uronic acid pathway. All transcripts coding enzymes involved in the ascorbate-glutathione cycle were also identified. Finally, we used the assembly to identified 6314 genic microsatellites and 23,481 high quality SNPs. This study describes the first next-generation sequencing effort and transcriptome annotation of a non-model Amazonian plant that is relevant for AsA production and other bioactive phytochemicals. Genes encoding key enzymes were successfully identified and metabolic pathways involved in biosynthesis of AsA, anthocyanins, and other metabolic pathways have been reconstructed. The identification of these genes and pathways is in agreement with the empirically observed capability of M. dubia to synthesize and accumulate AsA and other important molecules, and adds to our current knowledge of the molecular biology and biochemistry of their production in plants. By providing insights into the mechanisms underpinning these metabolic processes, these results can be used to direct efforts to genetically manipulate this organism in order to enhance the production of these bioactive phytochemicals. The accumulation of AsA precursor and discovery of genes associated with their biosynthesis and metabolism in M. dubia is intriguing and worthy of further investigation. The sequences and pathways produced here present the genetic framework required for further studies. Quantitative transcriptomics in concert with studies of the genome, proteome, and metabolome under conditions that stimulate production and accumulation of AsA and their precursors are needed to provide a more comprehensive view of how these pathways for AsA metabolism are regulated and linked in this species.
Venâncio, Paulo César; Raimundo Figueroba, Sidney; Dias Nani, Bruno; Eduardo Nunes Ferreira, Luiz; Vilela Muniz, Bruno; de Sá Del Fiol, Fernando; Sartoratto, Adilson; Antonio Ribeiro Rosa, Edvaldo; Carlos Groppo, Francisco
2017-04-01
Purpose: This study observed the effect of garlic extracts and amoxicillin against an induced staphylococcal infection model. MIC and MBC were also obtained for aqueous extracts of Allium sativum (Asa) and Allium tuberosum (Atu) against Staphylococcus aureus penicillin-sensitive (PSSA - ATCC 25923) and MRSA (ATCC 33592). Methods: Granulation tissues were induced in the back of 205 rats. After 14 days, 0.5 mL of 10 8 CFU/mL of PSSA or MRSA were injected inside tissues. After 24h, animals were divided: G1 (Control) - 0.5 mL of NaCl 0.9%; G2 - Asa 100 mg/kg or 400mg/kg; G3 - Atu 100 mg/kg or 400 mg/kg; G4 - amoxicillin suspension 50 mg/kg, considering PSSA infection; and G5 (Control) - 0.5 mL of NaCl 0.9%; G6 - Asa 400mg/kg; G7 - amoxicillin 50 mg/kg; and G8 - Asa 400 mg/kg + amoxicillin 50 mg/kg for MRSA. All treatments were administered P.O. every 6h. Animals were killed at 0, 6, 12 and 24h. Samples were spread on salt-mannitol agar. Colonies were counted after 18 h at 37 °C. Atu was not able to inhibit or kill PSSA and MRSA. Considering Asa, MIC and MBC against PSSA were 2 mg/mL and 4 mg/mL, respectively; and 16 mg/mL and 64 mg/mL against MRSA. Results: No effect was observed in vivo for control, Asa 100 mg/kg and Atu 100 mg/kg, while amoxicillin, Atu 400 mg/kg and Asa 400 mg/kg decreased PSSA counts in all-time points. No effect of any group against MRSA was observed at any time. Conclusion: Thus, A. sativum and A. tuberosum were able to reduce PSSA infection, but not MRSA infection.
Venâncio, Paulo César; Raimundo Figueroba, Sidney; Dias Nani, Bruno; Eduardo Nunes Ferreira, Luiz; Vilela Muniz, Bruno; de Sá Del Fiol, Fernando; Sartoratto, Adilson; Antonio Ribeiro Rosa, Edvaldo; Carlos Groppo, Francisco
2017-01-01
Purpose: This study observed the effect of garlic extracts and amoxicillin against an induced staphylococcal infection model. MIC and MBC were also obtained for aqueous extracts of Allium sativum (Asa) and Allium tuberosum (Atu) against Staphylococcus aureus penicillin-sensitive (PSSA - ATCC 25923) and MRSA (ATCC 33592). Methods: Granulation tissues were induced in the back of 205 rats. After 14 days, 0.5 mL of 108 CFU/mL of PSSA or MRSA were injected inside tissues. After 24h, animals were divided: G1 (Control) – 0.5 mL of NaCl 0.9%; G2 – Asa 100 mg/kg or 400mg/kg; G3 – Atu 100 mg/kg or 400 mg/kg; G4 – amoxicillin suspension 50 mg/kg, considering PSSA infection; and G5 (Control) - 0.5 mL of NaCl 0.9%; G6 – Asa 400mg/kg; G7 – amoxicillin 50 mg/kg; and G8 - Asa 400 mg/kg + amoxicillin 50 mg/kg for MRSA. All treatments were administered P.O. every 6h. Animals were killed at 0, 6, 12 and 24h. Samples were spread on salt-mannitol agar. Colonies were counted after 18 h at 37 °C. Atu was not able to inhibit or kill PSSA and MRSA. Considering Asa, MIC and MBC against PSSA were 2 mg/mL and 4 mg/mL, respectively; and 16 mg/mL and 64 mg/mL against MRSA. Results: No effect was observed in vivo for control, Asa 100 mg/kg and Atu 100 mg/kg, while amoxicillin, Atu 400 mg/kg and Asa 400 mg/kg decreased PSSA counts in all-time points. No effect of any group against MRSA was observed at any time. Conclusion: Thus, A. sativum and A. tuberosum were able to reduce PSSA infection, but not MRSA infection. PMID:28507945
Sá, Michel Pompeu Barros Oliveira; Soares, Artur Freire; Miranda, Rodrigo Gusmão Albuquerque; Araújo, Mayara Lopes; Menezes, Alexandre Motta; Silva, Frederico Pires Vasconcelos; Lima, Ricardo Carvalho
2017-11-01
This study aimed to evaluate the efficacy and safety of continuing versus stopping aspirin [acetylsalicylic acid (ASA)] preoperatively in patients undergoing coronary artery bypass graft surgery. MEDLINE, EMBASE, CENTRAL/Cochrane Controlled Trials Register (CCTR), ClinicalTrials.gov, Scientific Electronic Library Online (SciELO), Literatura Latino Americana em Ciências da Saúde (LILACS), Google Scholar and reference lists of relevant articles were searched for randomized controlled trials that reported efficacy outcomes of myocardial infarction and mortality, and safety outcomes of blood loss, packed red blood cell transfusion and surgical re-exploration were compared between groups. Fourteen studies fulfilled our eligibility criteria and included a total of 4499 patients (2329 for 'continuing ASA' and 2170 for 'stopping ASA'). In the pooled analysis, continuing aspirin therapy did not reduce the risk of myocardial infarction [risk ratio 0.834, 95% confidence interval (CI) 0.688-1.010; P = 0.063] or operative mortality (risk ratio 1.384, 95% CI 0.727-2.636; P = 0.323). Preoperative ASA increased postoperative chest tube drainage (mean difference 143 ml, 95% CI 39-248 ml; P = 0.007) and packed red blood cell transfusion (mean difference 142 ml, 95% CI 55-228; P = 0.001) but did not increase the risk of surgical re-exploration (risk ratio 1.316, 95% CI 0.910-1.905; P = 0.145). This meta-analysis found no statistically significant difference regarding the risk of operative mortality and myocardial infarction between the 'continuing ASA' and 'stopping ASA' strategies. On the other hand, the mean volume of blood loss and packed red blood cell transfusion was higher in the 'continuing ASA' group, but this finding did not translate into higher risk of reoperation for bleeding. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
Flores-Santana, Wilmarie; Moody, Terry; Chen, Weibin; Gorczynski, Michael J; Shoman, Mai E; Velázquez, Carlos; Thetford, Angela; Mitchell, James B; Cherukuri, Murali K; King, S Bruce; Wink, David A
2012-02-01
Inflammation and reactive oxygen species are associated with the promotion of various cancers. The use of non-steroidal anti-inflammatory drugs (NSAIDs) in cancer prevention treatments has been promising in numerous cancers. We report the evaluation of NSAIDs chemically modified by the addition of a redox-active nitroxide group. TEMPO-aspirin (TEMPO-ASA) and TEMPO-indomethacin (TEMPO-IND) were synthesized and evaluated in the lung cancer cell line A549. We evaluated physico-chemical properties of TEMPO-ASA and TEMPO-IND by electron paramagnetic resonance and cyclic voltammetry. Superoxide dismutase-like properties was assayed by measuring cytochrome c reduction and anti-inflammatory effects were assayed by measuring production of prostaglandin E(2) (PGE(2) ) and leukotriene B(4) (LTB(4) ). MTT proliferation assay and clonogenic assay were evaluated in the A549 lung carcinoma cell line. Maximum tolerated doses (MTD) and acute ulcerogenic index were also evaluated in in vivo. MTD were: TEMPO (140 mg·kg(-1) ), ASA (100 mg·kg(-1) ), indomethacin (5 mg·kg(-1) ), TEMPO-ASA (100 mg·kg(-1) ) and TEMPO-IND (40 mg·kg(-1) ). While TEMPO-ASA was as well tolerated as ASA, TEMPO-IND showed an eightfold improvement over indomethacin. TEMPO-IND showed markedly less gastric toxicity than the parent NSAID. Both TEMPO-ASA and TEMPO-IND inhibited production of PGE(2) and LTB(4) in A549 cells with maximum effects at 100 µg·mL(-1) or 10 µg·mL(-1) respectively. The nitroxide-NSAIDs retained superoxide scavenging capacity of the parent nitroxide and anti-inflammatory effects, inhibiting cyclooxygenase and 5-lipoxygenase enzymes. These redox-modified NSAIDs might be potential drug candidates, as they exhibit the pharmacological properties of the parent NSAID with antioxidant activity decreasing NSAID-associated toxicity. Published 2011. This article is a U.S. Government work and is in the public domain in the USA.
Steen, K H; Reeh, P W; Kreysel, H W
1996-01-01
In a human acid pain model, which uses continuous intradermal pressure infusion of a phosphate-buffered solution (pH 5.2) to induce localized non-adapting pain, the flow was adjusted to result in constant pain ratings of about 20% or 50% on a visual analog scale (VAS). Six volunteers in each group participated in 4 different placebo-controlled double-blind cross-over studies to measure rapidly evolving cutaneous analgesia from topically applied new ointment formulations of acetylsalicylic acid (ASA) and salicylic acid (SA) as well as of commercial ibuprofen and benzocain creams. Similar, log-linear dose-response curves were found for both ASA and SA, significant in effect at 3 g/kg and higher drug contents and reaching saturation level at 15 or 30 g/kg, respectively, which, 20 min after application, caused a mean pain suppression of 95% using ASA and 80% using SA. Half-maximal effects were achieved using 3 g/kg ASA or 15 g/kg SA. The SA action was also clearly slower to develop. With an increased flow of the acidic buffer, producing lower effective tissue pH and more intense pain, the effect of ASA and SA decreased to 73% pain suppression. A competitive mechanism of both drug effects was suggested by the fact that, with 15 g/kg ASA and SA, pain reduction could be reversed by increasing the buffer flow by a factor of 1.75, on average. Commercial ibuprofen (50 g/kg) and benzocain creams (100 g/kg) were comparably as effective as ASA and SA, but the local anesthetic caused a loss of all cutaneous sensations while the touch threshold (von Frey) under the specific analgesics was the same as under the placebo ointment. Thus, topical applications of non-steroidal anti-inflammatory drugs (NSAIDS) dissolved in different ointment formulations have proven dose-dependently effective and specific in suppressing experimental acidotic pain by a local and competitive mechanism.
You-Ten, Kong Eric; Bould, M Dylan; Friedman, Zeev; Riem, Nicole; Sydor, Devin; Boet, Sylvain
2015-05-01
Non-adherence to airway guidelines in a 'cannot intubate-cannot oxygenate' (CICO) crisis situation is associated with adverse patient outcomes. This study investigated the effects of hands-on training in cricothyrotomy on adherence to the American Society of Anesthesiologists difficult airway algorithm (ASA-DAA) during a simulated CICO scenario. A total of 21 postgraduate second-year anesthesia residents completed a pre-test teaching session during which they reviewed the ASA-DAA, became familiarized with the Melker cricothyrotomy kit, and watched a video on cricothyrotomy. Participants were randomized to either the intervention 'Trained' group (n = 10) (taught and practiced cricothyrotomy) or the control 'Non-Trained' group (n = 11) (no extra training). After two to three weeks, performances of the groups were assessed in a simulated CICO scenario. The primary outcome measure was major deviation from the ASA-DAA. Secondary outcome measures were (1) performance of the four categories of non-technical behaviours using the validated Anaesthetists' Non-Technical Skills scale (ANTS) and (2) time to perform specific tasks. Significantly more non-trained than trained participants (6/11 vs 0/10, P = 0.012) committed at least one major ASA-DAA deviation, including failure to insert an oral airway, failure to call for help, bypassing the laryngeal mask airway, and attempting fibreoptic intubation. ANTS scores for all four categories of behaviours, however, were similar between the groups. Trained participants called for help faster [26 (2) vs 63 (48) sec, P = 0.012] but delayed opening of the cricothyrotomy kit [130 (50) vs 74 (36) sec, P = 0.014]. Hands-on training in cricothyrotomy resulted in fewer major ASA-DAA deviations in a simulated CICO scenario. Training in cricothyrotomy may play an important role in complying with the ASA-DAA in a CICO situation but does not appear to affect non-technical behaviours such as decision-making.
Tenjarla, Srini; Abinusawa, Adeyinka
2011-01-01
Substantial variability in gastrointestinal pH is observed in patients with ulcerative colitis (UC). We characterized the effect of pH on 5-aminosalicylic acid (5-ASA) release from MMX mesalamine tablets (Shire Pharmaceuticals Inc., Wayne, PA, USA), examined thickness/uniformity of tablet film coatings, and explored the influence of simulating altered gastrointestinal motility. Nondestructive, three-dimensional, terahertz pulse imaging (TPI) was used to characterize the film coating of three lots of MMX mesalamine tablets (n=36). Thereafter, 5-ASA release from these tablets was evaluated using United States Pharmacopeia (USP) apparatus II at pH 6.8 and 7.2. Onset of tablet film-coat breach and mean dissolution time were determined for each lot. 5-ASA release was also assessed at three different paddle rotation speeds (50, 75, and 100 rpm) at pH 7.2. The mean ± SD film-coating thickness of the three lots of MMX mesalamine tablets were 109.2 ± 16.8, 113.1 ± 19.5, and 113.8 ± 19.8 μM, respectively. At pH 6.8 (100 rpm), the onset of film-coat breach was 10-30 minutes, whereas at pH 7.2 this was observed within 10 minutes. 5-ASA release was uniform at both pH conditions, with minimal lot-to-lot variability. Complete drug release was achieved within 6 hours under both pH conditions. 5-ASA release increased in proportion with paddle speed, but remained prolonged at all speeds. 5-ASA release from MMX mesalamine is unaffected by normal variations in simulated intracolonic pH. The dissolution profile of 5-ASA from MMX mesalamine tablets may be attributed to consistent outer film coatings and the hydrogel-forming matrix that controls the drug release after dissolution of the film coating.
LUCIANI, M. GLORIA; CAMPREGHER, CHRISTOPH; FORTUNE, JOHN M.; KUNKEL, THOMAS A.; GASCHE, CHRISTOPH
2007-01-01
Background & Aims Individuals with inflammatory bowel disease are at risk of developing colorectal cancer (CRC). Epidemiologic, animal, and laboratory studies suggest that 5-amino-salicylic acid (5-ASA) protects from the development of CRC by altering cell cycle progression and by inducing apoptosis. Our previous results indicate that 5-ASA improves replication fidelity in colorectal cells, an effect that is active in reducing mutations. In this study, we hypothesized that 5-ASA restrains cell cycle progression by activating checkpoint pathways in colorectal cell lines, which would prevent tumor development and improve genomic stability. Methods CRC cells with different genetic backgrounds such as HT29, HCT116, HCT116p53−/−, HCT116+chr3, and LoVo were treated with 5-ASA for 2–96 hours. Cell cycle progression, phosphorylation, and DNA binding of cell cycle checkpoint proteins were analyzed. Results We found that 5-ASA at concentrations between 10 and 40 mmol/L affects cell cycle progression by inducing cells to accumulate in the S phase. This effect was independent of the hMLH1, hMSH2, and p53 status because it was observed to a similar extent in all cell lines under investigation. Moreover, wash-out experiments demonstrated reversibility within 48 hours. Although p53 did not have a causative role, p53 Ser15 was strongly phosphorylated. Proteins involved in the ATM-and-Rad3-related kinase (ATR)-dependent S-phase checkpoint response (Chk1 and Rad17) were also phosphorylated but not ataxia telengectasia mutated kinase. Conclusions Our data demonstrate that 5-ASA causes cells to reversibly accumulate in S phase and activate an ATR-dependent checkpoint. The activation of replication checkpoint may slow down DNA replication and improve DNA replication fidelity, which increases the maintenance of genomic stability and counteracts carcinogenesis. PMID:17241873
Klous, Miriam; Mikulic, Pavle; Latash, Mark L
2011-05-01
We used the framework of the uncontrolled manifold hypothesis to explore the relations between anticipatory synergy adjustments (ASAs) and anticipatory postural adjustments (APAs) during feedforward control of vertical posture. ASAs represent a drop in the index of a multimuscle-mode synergy stabilizing the coordinate of the center of pressure in preparation to an action. ASAs reflect early changes of an index of covariation among variables reflecting muscle activation, whereas APAs reflect early changes in muscle activation levels averaged across trials. The assumed purpose of ASAs is to modify stability of performance variables, whereas the purpose of APAs is to change magnitudes of those variables. We hypothesized that ASAs would be seen before APAs and that this finding would be consistent with regard to the muscle-mode composition defined on the basis of different tasks and phases of action. Subjects performed a voluntary body sway task and a quick, bilateral shoulder flexion task under self-paced and reaction time conditions. Surface muscle activity of 12 leg and trunk muscles was analyzed to identify sets of 4 muscle modes for each task and for different phases within the shoulder flexion task. Variance components in the muscle-mode space and indexes of multimuscle-mode synergy stabilizing shift of the center of pressure were computed. ASAs were seen ∼ 100-150 ms prior to the task initiation, before APAs. The results were consistent with respect to different sets of muscle modes defined over the two tasks and different shoulder flexion phases. We conclude that the preparation for a self-triggered postural perturbation is associated with two types of anticipatory adjustments, ASAs and APAs. They reflect different feedforward processes within the hypothetical hierarchical control scheme, resulting in changes in patterns of covariation of elemental variables and in their patterns averaged across trials, respectively. The results show that synergies quantified using dissimilar sets of muscle modes show similar feedforward changes in preparation to action.
Optimal approximation of harmonic growth clusters by orthogonal polynomials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Teodorescu, Razvan
2008-01-01
Interface dynamics in two-dimensional systems with a maximal number of conservation laws gives an accurate theoreticaI model for many physical processes, from the hydrodynamics of immiscible, viscous flows (zero surface-tension limit of Hele-Shaw flows), to the granular dynamics of hard spheres, and even diffusion-limited aggregation. Although a complete solution for the continuum case exists, efficient approximations of the boundary evolution are very useful due to their practical applications. In this article, the approximation scheme based on orthogonal polynomials with a deformed Gaussian kernel is discussed, as well as relations to potential theory.
Organic textile waste as a resource for sustainable agriculture in arid and semi-arid areas.
Eriksson, Bo G
2017-03-01
New vegetation in barren areas offers possibilities for sequestering carbon in the soil. Arid and semi-arid areas (ASAs) are candidates for new vegetation. The possibility of agriculture in ASAs is reviewed, revealing the potential for cultivation by covering the surface with a layer of organic fibres. This layer collects more water from humidity in the air than does the uncovered mineral surface, and creates a humid environment that promotes microbial life. One possibility is to use large amounts of organic fibres for soil enhancement in ASAs. In the context of the European Commission Waste Framework Directive, the possibility of using textile waste from Sweden is explored. The costs for using Swedish textile waste are high, but possible gains are the sale of agricultural products and increased land prices as well as environmental mitigation. The findings suggest that field research on such agriculture in ASAs should start as soon as possible.
NASA Astrophysics Data System (ADS)
Pojmanski, G.; Maciejewski, G.
2005-03-01
In this paper we present the fourth part of the photometric data from the 9 arcdeg x 9 arcdeg ASAS camera monitoring the whole southern hemisphere in V-band. Preliminary list (based on observations obtained since January 2001) of variable stars located between RA 18^h and 24^h is released. 10311 stars brighter than V=15 mag were found to be variable (1641 eclipsing, 1116 regularly pulsating, 938 Mira-type and 6616 other stars). Light curves have been classified using the automated algorithm taking into account periods, amplitudes, Fourier coefficients of the light curves, 2MASS colors and IRAS infrared fluxes. Basic photometric properties are presented in the tables and some examples of thumbnail light curves are printed for reference. All photometric data are available over the Internet at http://www.astrouw.edu.pl/~gp/asas/asas.html or http://archive.princeton.edu/~asas
Symptoms of anxiety and associated risk and protective factors in young Asian American children.
Huang, Keng-Yen; Cheng, Sabrina; Calzada, Esther; Brotman, Laurie Miller
2012-10-01
Anxiety is one of the most prevalent mental health problems in young children but there has been a dearth of studies focusing on Asian American children. This study examines the patterns and the predictors of childhood anxiety and related symptoms in young children in a diverse Asian American (ASA) sample (n = 101). Findings indicate that ASA children are at higher risk for anxiety, somatization, and depressive problems than their peers. Parents' level of acculturation (i.e., American identity, English competence), parental negative emotion socialization, conflicted parent-child relationship, child emotional knowledge and adaptive skills, as well as teachers' ethnic background and school class types were all associated with ASA children's anxiety. A combination of cultural, family, and school factors explained from 17 to 39 % of the variance in anxiety symptoms. Findings inform prevention services for young ASA children.
NASA Astrophysics Data System (ADS)
Pojmanski, G.
2003-12-01
This paper describes the second part of the photometric data from the 9 arcdeg times 9 arcdeg ASAS camera monitoring the whole southern hemisphere in the V-band. Preliminary list of variable stars based on observations obtained since January 2001 is presented. Over 2800000 stars brighter than V=15 mag on 18000 frames were analyzed and 11357 were found to be variable (2685 eclipsing, 907 regularly pulsating, 521 Mira and 7244 other, mostly SR, IRR and LPV stars). Periodic light curves have been classified using the automated algorithm, which now takes into account IRAS infrared fluxes. Basic photometric properties are presented in the tables and some examples of thumbnail light curves are printed for reference. All photometric data are available over the INTERNET at http://www.astrouw.edu.pl/~gp/asas/asas.html or http://archive.princeton.edu/~asas.
NASA Astrophysics Data System (ADS)
Pojmanski, G.; Maciejewski, G.
2004-06-01
This paper describes the third part of the photometric data from the 9 arcdeg x 9arcdeg ASAS camera monitoring the whole southern hemisphere in V-band. Preliminary list of variable stars based on observations obtained since January 2001 is presented. Over 3200000 stars brighter than V=15 mag on 18000 frames were analyzed and 10453 were found to be variable (1718 eclipsing, 731 regularly pulsating, 849 Mira and 7155 other stars). Light curves have been classified using the improved automated algorithm, which now takes into account 2MASS colors and IRAS infrared fluxes. Basic photometric properties are presented in the tables and some examples of thumbnail light curves are printed for reference. All photometric data are available over the INTERNET at http://www.astrouw.edu.pl/\\gp/asas/asas.html or http://archive.princeton.edu/\\asas.
Symptoms of Anxiety and Associated Risk and Protective Factors in Young Asian American Children
Cheng, Sabrina; Calzada, Esther; Brotman, Laurie Miller
2014-01-01
Anxiety is one of the most prevalent mental health problems in young children but there has been a dearth of studies focusing on Asian American children. This study examines the patterns and the predictors of childhood anxiety and related symptoms in young children in a diverse Asian American (ASA) sample (n = 101). Findings indicate that ASA children are at higher risk for anxiety, somatization, and depressive problems than their peers. Parents’ level of acculturation (i.e., American identity, English competence), parental negative emotion socialization, conflicted parent–child relationship, child emotional knowledge and adaptive skills, as well as teachers’ ethnic background and school class types were all associated with ASA children’s anxiety. A combination of cultural, family, and school factors explained from 17 to 39 % of the variance in anxiety symptoms. Findings inform prevention services for young ASA children. PMID:22410755
Antisperm antibodies and fertility association.
Restrepo, B; Cardona-Maya, W
2013-10-01
To evaluate the relation between antisperm antibodies (ASA) and human fertility by reviewing the scientific literature of the last 45 years. We carried out a review of scientific literature about antisperm antibodies and infertility published in spanish or english in databases as Pubmed, Medline, Scielo, some books and another gray literature include information related to this review and that is published in the last 45 years. Infertile couples suffer infertility by immunological mechanisms mainly by the presence of antisperm antibodies ASA in blood, semen or cervicovaginal secretions; the formation of ASA in men and women may be associated with disturbance in immunomodulatory mechanisms that result in functional impairment of sperm and thus its inability to fertilize the oocyte. Immunological infertility caused by ASA is the result of interference of these antibodies in various stages of fertilization process, inhibiting the ability of interaction between sperm and oocyte. Copyright © 2012 AEU. Published by Elsevier Espana. All rights reserved.
NASA Astrophysics Data System (ADS)
Hansen, Uwe J.; Everbach, E. Carr
2003-04-01
A number of very successful Hands-on demo sessions for high school students have been a part of regular ASA meetings for some time. In addition, the Education Committee has organized a series of teacher workshops. These workshops are designed to give high school teachers relatively sophisticated tools to enhance their laboratory content. Workshops for teachers in the elementary grades prepare teachers to use music as a vehicle to introduce additional science concepts. Content and methods associated with both workshops will be discussed. Cyberspace outreach by the ASA was accelerated by the establishment of a Home Page Committee, and more recently by the On-Line Education committee, which is creating an educational website. The website provides a fun way for users to access information including acoustics information, history, demos, and links to the Technical Committee's webpages. The ASA has joined other AIP member societies in developing additional mechanisms, including road shows and nightly news spots.
Hydration of AN Acid Anhydride: the Water Complex of Acetic Sulfuric Anhydride
NASA Astrophysics Data System (ADS)
Smith, CJ; Huff, Anna; Mackenzie, Becca; Leopold, Ken
2017-06-01
The water complex of acetic sulfuric anhydride (ASA, CH_{3}COOSO_{2}OH) has been observed by pulsed nozzle Fourier transform microwave spectroscopy. ASA is formed in situ in the supersonic jet via the reaction of SO_{3} and acetic acid and subsequently forms a complex with water during the expansion. Spectra of the parent and fully deuterated form, as well as those of the species derived from CH_{3}^{13}COOH, have been observed. The fitted internal rotation barrier of the methyl group is 219.599(21), \\wn indicating the complexation with water lowers the internal rotation barrier of the methyl group by 9% relative to that of free ASA. The observed species is one of several isomers identified theoretically in which the water inserts into the intramolecular hydrogen bond of the ASA. Aspects of the intermolecular potential energy surface are discussed.
van der Heijde, Désirée; Deodhar, Atul; Wei, James C; Drescher, Edit; Fleishaker, Dona; Hendrikx, Thijs; Li, David; Menon, Sujatha; Kanik, Keith S
2017-08-01
To compare efficacy and safety of various doses of tofacitinib, an oral Janus kinase inhibitor, with placebo in patients with active ankylosing spondylitis (AS, radiographic axial spondyloarthritis). In this 16-week (12-week treatment, 4-week washout), phase II, multicentre, dose-ranging trial, adult patients with active AS were randomised (N=51, 52, 52, 52, respectively) to placebo or tofacitinib 2, 5 or 10 mg twice daily. The primary efficacy endpoint was Assessment of SpondyloArthritis International Society 20% improvement (ASAS20) response rate at week 12. Secondary endpoints included objective measures of disease activity, patient-reported outcomes and MRI of sacroiliac joints and spine. Safety was monitored. Emax model analysis of the primary endpoint predicted a tofacitinib 10 mg twice daily ASAS20 response rate of 67.4%, 27.3% higher than placebo. Supportive normal approximation analysis demonstrated tofacitinib 5 mg twice daily ASAS20 response rate significantly higher than placebo (80.8% vs 41.2%; p<0.001); tofacitinib 2 and 10 mg twice daily demonstrated greater response rate than placebo (51.9% and 55.8%, respectively; not significant). Secondary endpoints generally demonstrated greater improvements with tofacitinib 5 and 10 mg twice daily than placebo. Objective (including MRI) endpoints demonstrated clear dose response. Adverse events were similar across treatment groups with no unexpected safety findings. Dose-dependent laboratory outcome changes returned close to baseline by week 16. Tofacitinib 5 and 10 mg twice daily demonstrated greater clinical efficacy versus placebo in reducing signs, symptoms and objective endpoints of active AS in adult patients with a similar 12-week safety profile as reported in other indications. NCT01786668. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Miron, Lynsey R; Orcutt, Holly K
2014-11-01
Research suggests that adverse events in childhood, such as childhood physical, sexual, and emotional abuse, confer risk for later sexual assault. Psychological distress, coping strategies, and sexual behavior may help explain the path from childhood abuse to revictimization. The present study explored how the use of sex to regulate negative affect (SRNA) operates independently, and in combination with other psychosocial factors to increase college women's (N=541) risk of experiencing prospective adult sexual assault (ASA). Sequential multiple mediator models in Mplus were used to assess the effect of three different forms of childhood abuse on prospective ASA, both independently and while controlling for other forms of childhood abuse. The indirect effect of adolescent sexual assault (AdolSA), depressive symptoms, SRNA, and participants' response to a sex-related vignette was tested using bias-corrected bootstrapping. In the full path model, childhood emotional abuse and AdolSA predicted ASA, while childhood physical and sexual abuse were directly associated with AdolSA, but not ASA. Additionally, depressive symptoms and participants' estimate of their likely behavior in a sex-related vignette directly predicted prospective ASA. Results using bootstrapping revealed that a history of childhood abuse predicted prospective ASA via diverse direct and indirect paths, as well as through a similar multiple mediator path. Overall, findings suggest that a combination of affective, coping, and sexual expectancy factors contribute to risk for revictimization in adult survivors of childhood abuse. Future research directions and targets for risk-reduction programming are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.
Zimmerman, Thea Palmer; Hull, Stephen G; McNutt, Suzanne; Mittl, Beth; Islam, Noemi; Guenther, Patricia M; Thompson, Frances E; Potischman, Nancy A; Subar, Amy F
2009-12-01
The National Cancer Institute (NCI) is developing an automated, self-administered 24-hour dietary recall (ASA24) application to collect and code dietary intake data. The goal of the ASA24 development is to create a web-based dietary interview based on the US Department of Agriculture (USDA) Automated Multiple Pass Method (AMPM) instrument currently used in the National Health and Nutrition Examination Survey (NHANES). The ASA24 food list, detail probes, and portion probes were drawn from the AMPM instrument; portion-size pictures from Baylor College of Medicine's Food Intake Recording Software System (FIRSSt) were added; and the food code/portion code assignments were linked to the USDA Food and Nutrient Database for Dietary Studies (FNDDS). The requirements that the interview be self-administered and fully auto-coded presented several challenges as the AMPM probes and responses were linked with the FNDDS food codes and portion pictures. This linking was accomplished through a "food pathway," or the sequence of steps that leads from a respondent's initial food selection, through the AMPM probes and portion pictures, to the point at which a food code and gram weight portion size are assigned. The ASA24 interview database that accomplishes this contains more than 1,100 food probes and more than 2 million food pathways and will include about 10,000 pictures of individual foods depicting up to 8 portion sizes per food. The ASA24 will make the administration of multiple days of recalls in large-scale studies economical and feasible.
NASA Astrophysics Data System (ADS)
Richards, Joseph W.; Starr, Dan L.; Miller, Adam A.; Bloom, Joshua S.; Butler, Nathaniel R.; Brink, Henrik; Crellin-Quick, Arien
2012-12-01
With growing data volumes from synoptic surveys, astronomers necessarily must become more abstracted from the discovery and introspection processes. Given the scarcity of follow-up resources, there is a particularly sharp onus on the frameworks that replace these human roles to provide accurate and well-calibrated probabilistic classification catalogs. Such catalogs inform the subsequent follow-up, allowing consumers to optimize the selection of specific sources for further study and permitting rigorous treatment of classification purities and efficiencies for population studies. Here, we describe a process to produce a probabilistic classification catalog of variability with machine learning from a multi-epoch photometric survey. In addition to producing accurate classifications, we show how to estimate calibrated class probabilities and motivate the importance of probability calibration. We also introduce a methodology for feature-based anomaly detection, which allows discovery of objects in the survey that do not fit within the predefined class taxonomy. Finally, we apply these methods to sources observed by the All-Sky Automated Survey (ASAS), and release the Machine-learned ASAS Classification Catalog (MACC), a 28 class probabilistic classification catalog of 50,124 ASAS sources in the ASAS Catalog of Variable Stars. We estimate that MACC achieves a sub-20% classification error rate and demonstrate that the class posterior probabilities are reasonably calibrated. MACC classifications compare favorably to the classifications of several previous domain-specific ASAS papers and to the ASAS Catalog of Variable Stars, which had classified only 24% of those sources into one of 12 science classes.
Cannesson, Maxime; Pestel, Gunther; Ricks, Cameron; Hoeft, Andreas; Perel, Azriel
2011-08-15
Several studies have demonstrated that perioperative hemodynamic optimization has the ability to improve postoperative outcome in high-risk surgical patients. All of these studies aimed at optimizing cardiac output and/or oxygen delivery in the perioperative period. We conducted a survey with the American Society of Anesthesiologists (ASA) and the European Society of Anaesthesiology (ESA) to assess current hemodynamic management practices in patients undergoing high-risk surgery in Europe and in the United States. A survey including 33 specific questions was emailed to 2,500 randomly selected active members of the ASA and to active ESA members. Overall, 368 questionnaires were completed, 57.1% from ASA and 42.9% from ESA members. Cardiac output is monitored by only 34% of ASA and ESA respondents (P = 0.49) while central venous pressure is monitored by 73% of ASA respondents and 84% of ESA respondents (P < 0.01). Specifically, the pulmonary artery catheter is being used much more frequently in the US than in Europe in the setup of high-risk surgery (85.1% vs. 55.3% respectively, P < 0.001). Clinical experience, blood pressure, central venous pressure, and urine output are the most widely indicators of volume expansion. Finally, 86.5% of ASA respondents and 98.1% of ESA respondents believe that their current hemodynamic management could be improved. In conclusion, these results point to a considerable gap between the accumulating evidence about the benefits of perioperative hemodynamic optimization and the available technologies that may facilitate its clinical implementation, and clinical practices in both Europe and the United States.
Miron, Lynsey R.; Orcutt, Holly K.
2014-01-01
Research suggests that adverse events in childhood, such as childhood physical, sexual, and emotional abuse, confer risk for later sexual assault. Psychological distress, coping strategies, and sexual behavior may help explain the path from childhood abuse to revictimization. The present study explored how the use of sex to regulate negative affect (SRNA) operates independently, and in combination with other psychosocial factors to increase college women’s (N = 541) risk of experiencing prospective adult sexual assault (ASA). Sequential multiple mediator models in Mplus were used to assess the effect of three different forms of childhood abuse on prospective ASA, both independently and while controlling for other forms of childhood abuse. The indirect effect of adolescent sexual assault (AdolSA), depressive symptoms, SRNA, and participants’ response to a sex-related vignette was tested using bias-corrected bootstrapping. In the full path model, childhood emotional abuse and AdolSA predicted ASA, while childhood physical and sexual abuse were directly associated with AdolSA, but not ASA. Additionally, depressive symptoms and participants’ estimate of their likely behavior in a sex-related vignette directly predicted prospective ASA. Results using bootstrapping revealed that a history of childhood abuse predicted prospective ASA via diverse direct and indirect paths, as well as through a similar multiple mediator path. Overall, findings suggest that a combination of affective, coping, and sexual expectancy factors contribute to risk for revictimization in adult survivors of childhood abuse. Future research directions and targets for risk-reduction programming will be discussed. PMID:25455965
Cathcart, Curtis J; Brainard, Benjamin M; Reynolds, Lisa R; Al-Nadaf, Sami; Budsberg, Steven C
2012-02-01
To determine the effects of acetylsalicylic acid (ASA) and meloxicam on feline platelet aggregation and associated platelet thromboxane production and serotonin release. Prospective interventional study. University research facility. Eight healthy male castrated domestic short hair cats from a research colony. Oral medications were administered to 8 cats for 14 days in a randomized, placebo-controlled, crossover design. Treatment groups included: aspirin (ASA) (5 mg/kg q 48 h), meloxicam (0.05 mg/kg q 24 h), and placebo (0.5 mL of water q 24 h). Thromboxane assays (TXB(2) ) and whole blood (impedance) aggregometry (WBA) were performed on samples collected before drug administration, and on days 7, 15, and 17, using adenosine diphosphate (ADP; 10 μM) and collagen (5 μg/mL) as agonists for WBA. Serotonin release was assayed on postaggregation plasma. Oral mucosal bleeding time (OMBT) and complete blood cell counts were measured on days 0 and 15. Neither medication affected WBA at any time point. OMBT decreased in the ASA group relative to baseline. No differences were detected in WBA and OMBT baseline between any groups. No difference was detected in serotonin secretion at any time point. TXB(2) was significantly decreased in the ASA group at all times after initiation of treatment but no change was noted in the meloxicam or placebo groups. At the doses studied, neither meloxicam nor ASA had an inhibitory effect on WBA or OMBT in cats. Thromboxane concentrations were significantly decreased with ASA treatment. © Veterinary Emergency and Critical Care Society 2011.
An Energy Aware Adaptive Sampling Algorithm for Energy Harvesting WSN with Energy Hungry Sensors
Srbinovski, Bruno; Magno, Michele; Edwards-Murphy, Fiona; Pakrashi, Vikram; Popovici, Emanuel
2016-01-01
Wireless sensor nodes have a limited power budget, though they are often expected to be functional in the field once deployed for extended periods of time. Therefore, minimization of energy consumption and energy harvesting technology in Wireless Sensor Networks (WSN) are key tools for maximizing network lifetime, and achieving self-sustainability. This paper proposes an energy aware Adaptive Sampling Algorithm (ASA) for WSN with power hungry sensors and harvesting capabilities, an energy management technique that can be implemented on any WSN platform with enough processing power to execute the proposed algorithm. An existing state-of-the-art ASA developed for wireless sensor networks with power hungry sensors is optimized and enhanced to adapt the sampling frequency according to the available energy of the node. The proposed algorithm is evaluated using two in-field testbeds that are supplied by two different energy harvesting sources (solar and wind). Simulation and comparison between the state-of-the-art ASA and the proposed energy aware ASA (EASA) in terms of energy durability are carried out using in-field measured harvested energy (using both wind and solar sources) and power hungry sensors (ultrasonic wind sensor and gas sensors). The simulation results demonstrate that using ASA in combination with an energy aware function on the nodes can drastically increase the lifetime of a WSN node and enable self-sustainability. In fact, the proposed EASA in conjunction with energy harvesting capability can lead towards perpetual WSN operation and significantly outperform the state-of-the-art ASA. PMID:27043559
Li, Ying; Chu, Zhuannan; Luo, Jinying; Zhou, Yuhong; Cai, Yujing; Lu, Yongen; Xia, Junhui; Kuang, Hanhui; Ye, Zhibiao; Ouyang, Bo
2018-06-01
Abiotic stresses are a major cause of crop loss. Ascorbic acid (AsA) promotes stress tolerance by scavenging reactive oxygen species (ROS), which accumulate when plants experience abiotic stress. Although the biosynthesis and metabolism of AsA are well established, the genes that regulate these pathways remain largely unexplored. Here, we report on a novel regulatory gene from tomato (Solanum lycopersicum) named SlZF3 that encodes a Cys2/His2-type zinc-finger protein with an EAR repression domain. The expression of SlZF3 was rapidly induced by NaCl treatments. The overexpression of SlZF3 significantly increased the levels of AsA in tomato and Arabidopsis. Consequently, the AsA-mediated ROS-scavenging capacity of the SlZF3-overexpressing plants was increased, which enhanced the salt tolerance of these plants. Protein-protein interaction assays demonstrated that SlZF3 directly binds CSN5B, a key component of the COP9 signalosome. This interaction inhibited the binding of CSN5B to VTC1, a GDP-mannose pyrophosphorylase that contributes to AsA biosynthesis. We found that the EAR domain promoted the stability of SlZF3 but was not required for the interaction between SlZF3 and CSN5B. Our findings indicate that SlZF3 simultaneously promotes the accumulation of AsA and enhances plant salt-stress tolerance. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Cuesta-Gragera, Ana; Navarro-Fontestad, Carmen; Mangas-Sanjuan, Victor; González-Álvarez, Isabel; García-Arieta, Alfredo; Trocóniz, Iñaki F; Casabó, Vicente G; Bermejo, Marival
2015-07-10
The objective of this paper is to apply a previously developed semi-physiologic pharmacokinetic model implemented in NONMEM to simulate bioequivalence trials (BE) of acetyl salicylic acid (ASA) in order to validate the model performance against ASA human experimental data. ASA is a drug with first-pass hepatic and intestinal metabolism following Michaelis-Menten kinetics that leads to the formation of two main metabolites in two generations (first and second generation metabolites). The first aim was to adapt the semi-physiological model for ASA in NOMMEN using ASA pharmacokinetic parameters from literature, showing its sequential metabolism. The second aim was to validate this model by comparing the results obtained in NONMEM simulations with published experimental data at a dose of 1000 mg. The validated model was used to simulate bioequivalence trials at 3 dose schemes (100, 1000 and 3000 mg) and with 6 test formulations with decreasing in vivo dissolution rate constants versus the reference formulation (kD 8-0.25 h (-1)). Finally, the third aim was to determine which analyte (parent drug, first generation or second generation metabolite) was more sensitive to changes in formulation performance. The validation results showed that the concentration-time curves obtained with the simulations reproduced closely the published experimental data, confirming model performance. The parent drug (ASA) was the analyte that showed to be more sensitive to the decrease in pharmaceutical quality, with the highest decrease in Cmax and AUC ratio between test and reference formulations. Copyright © 2015 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Richards, Joseph W.; Starr, Dan L.; Miller, Adam A.
2012-12-15
With growing data volumes from synoptic surveys, astronomers necessarily must become more abstracted from the discovery and introspection processes. Given the scarcity of follow-up resources, there is a particularly sharp onus on the frameworks that replace these human roles to provide accurate and well-calibrated probabilistic classification catalogs. Such catalogs inform the subsequent follow-up, allowing consumers to optimize the selection of specific sources for further study and permitting rigorous treatment of classification purities and efficiencies for population studies. Here, we describe a process to produce a probabilistic classification catalog of variability with machine learning from a multi-epoch photometric survey. In additionmore » to producing accurate classifications, we show how to estimate calibrated class probabilities and motivate the importance of probability calibration. We also introduce a methodology for feature-based anomaly detection, which allows discovery of objects in the survey that do not fit within the predefined class taxonomy. Finally, we apply these methods to sources observed by the All-Sky Automated Survey (ASAS), and release the Machine-learned ASAS Classification Catalog (MACC), a 28 class probabilistic classification catalog of 50,124 ASAS sources in the ASAS Catalog of Variable Stars. We estimate that MACC achieves a sub-20% classification error rate and demonstrate that the class posterior probabilities are reasonably calibrated. MACC classifications compare favorably to the classifications of several previous domain-specific ASAS papers and to the ASAS Catalog of Variable Stars, which had classified only 24% of those sources into one of 12 science classes.« less
Boubacar Ba, El Hadji; Leye, Papa Alassane; Traoré, Mamadou Mour; Ndiaye, Pape Ibrahima; Gaye, Ibrahima; Bah, Mamadou Diawo; Fall, Mamadou Lamine; Diouf, Elisabeth
2017-01-01
Emergency anesthesia in elderly patients aged 65 years and older is complex. The occurrence of intraoperative incidents and arterial hypotension is conditioned by patients' initial health status and by the quality of intraoperative management. This study aimed to determine the incidence of intra-anesthetic arterial hypotension in elderly patients during emergency surgery and to assess the involvement of certain factors in its occurrence: age, sex, patient's history, ASA class, anesthetic technique. We conducted a retrospective descriptive and analytical study in the Emergency Surgery Department at the Aristide Le Dantec University Hospital from 1 March 2014 to 28 February 2015. We collected data from 210 patients out of 224 elderly patients aged 65 years and older undergoing emergency anesthesias (10.93%). Data of 101 men and 109 women were included in the analysis, of whom 64.3% had at least one defect. Patients' preoperative status was assessed using American Society of Anesthesiology (ASA) classification: 71% of patients were ASA class 1 and 2 and 29% were ASA class 3 and 4. Locoregional anesthesia was the most practiced anesthetic technique (56.7%). 28 patients (13.33%) had intra-anesthetic arterial hypotension, of whom 16 under general anesthesia and 12 under locoregional anesthesia. It was more frequent in patients with high ASA class and a little less frequent in patients with PAH and underlying heart disease. Arterial hypotension in elderly patients during emergency surgery exposes the subject to the risk of not negligible intraoperative hypotension, especially in patients with high ASA class. Prevention is based on adequate preoperative assessment and anesthetic management.
Khvostov, Mikhail V; Tolstikova, Tatjana G; Borisov, Sergey A; Zhukova, Natalja A; Dushkin, Alexander V; Chistyachenko, Yulia S; Polyakov, Nikolay E
2016-01-01
The main undesirable side effect of the aspirin is the damage to the gastrointestinal mucosa, leading to the formation of erosions, peptic ulcers, and as a result, bleeding. To overcome this problem "host-guest" complexation with natural polysaccharide arabinogalactan could be applied. The complex with a weight ratio of ASA:AG = 1:10 was prepared by solid phase method in a rotary mill. Complex was administered orally to mice or rats at doses of 250, 500 or 1000 mg/kg. The "acetic acid induced writhing" and "hot plate" tests were used as an in vivo pain models. The antiinflammatory activity was studied using "histamine swelling" test. Also, long-term (30 days) oral introduction of the complex to rats was performed and gastric mucosa damages were evaluated. In all experiments pure aspirin (ASA) was used as a control in appropriate doses. The minimal effective analgesic dose of the complex was 250 mg/kg, equivalent to 23 mg/kg of ASA, a dose in which aspirin itself was not active. The anti-inflammatory effect was found at relatively higher doses: 500 and 1000 mg/kg (46 and 92 mg/kg of ASA respectively) for the complex and only at 100 mg/kg for the ASA. Long-term introduction of the complex at doses of 250 and 500 mg/kg was safe for gastric mucosa, while ASA at the dose of 50 mg/kg showed a strong gastric mucosal damage. The effective analgesic and anti-inflammatory doses of 1:10 aspirin complex with arabinogalactan are twice less compared to pure aspirin and safer for the gastrointestinal mucosa.
Truitt, E B; Gaynor, C R; Mehl, D L
1987-01-01
Aspirin (ASA) was tested in a group of 8 Oriental and 3 Occidental subjects who were shown in a previous study to respond to small doses of ethanol (0.06-0.25 g/kg) with facial flushing. They were compared to a similar group of 11 non-flushing Occidental subjects following a larger ethanol dose (0.37 g/kg) to determine if similar effects could be produced in less sensitive individuals. Control tests of blood ethanol and acetaldehyde (AcH) levels (calculated from breath), facial and neck skin temperatures, body sway (Romberg test), blood pressure, heart rate and 10 Subjective High Assessment Scales (SHAS-Judd, 1977) were conducted before and at 15, 30, 60 and 90 minutes after drinking ethanol as vodka in orange juice. The tests were repeated one week later one hour after receiving 0.64 gm of ASA orally. ASA produced slight changes in the early absorption of ethanol and small decreases in AcH levels in the flushing and non-flushing groups. Facial flushing was markedly reduced in the flushing group, but was slightly increased in the non-flushing Occidentals. Body sway was reduced by ASA in both groups. An alcohol-induced increase in heart rate in the flushing group was reduced with no change in blood pressure. SHAS subjective parameters were widely variable, but indicated that ASA produced reduced sleepiness and earlier relaxation in the flushing group. It is concluded that ASA can block alcohol-induced facial flushing in sensitive subjects and also reduces body sway in the Romberg test and alters some subjective feelings of alcohol intoxication.
Duignan, Timothy T.; Baer, Marcel D.; Schenter, Gregory K.; ...
2017-07-26
Determining the solvation free energies of single ions in water is one of the most fundamental problems in physical chemistry and yet many unresolved questions remain. In particular, the ability to decompose the solvation free energy into simple and intuitive contributions will have important implications for models of electrolyte solution. In this paper, we provide definitions of the various types of single ion solvation free energies based on different simulation protocols. We calculate solvation free energies of charged hard spheres using density functional theory interaction potentials with molecular dynamics simulation and isolate the effects of charge and cavitation, comparing tomore » the Born (linear response) model. We show that using uncorrected Ewald summation leads to unphysical values for the single ion solvation free energy and that charging free energies for cations are approximately linear as a function of charge but that there is a small non-linearity for small anions. The charge hydration asymmetry for hard spheres, determined with quantum mechanics, is much larger than for the analogous real ions. Finally, this suggests that real ions, particularly anions, are significantly more complex than simple charged hard spheres, a commonly employed representation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Duignan, Timothy T.; Baer, Marcel D.; Schenter, Gregory K.
Determining the solvation free energies of single ions in water is one of the most fundamental problems in physical chemistry and yet many unresolved questions remain. In particular, the ability to decompose the solvation free energy into simple and intuitive contributions will have important implications for models of electrolyte solution. In this paper, we provide definitions of the various types of single ion solvation free energies based on different simulation protocols. We calculate solvation free energies of charged hard spheres using density functional theory interaction potentials with molecular dynamics simulation and isolate the effects of charge and cavitation, comparing tomore » the Born (linear response) model. We show that using uncorrected Ewald summation leads to unphysical values for the single ion solvation free energy and that charging free energies for cations are approximately linear as a function of charge but that there is a small non-linearity for small anions. The charge hydration asymmetry for hard spheres, determined with quantum mechanics, is much larger than for the analogous real ions. Finally, this suggests that real ions, particularly anions, are significantly more complex than simple charged hard spheres, a commonly employed representation.« less
NASA Astrophysics Data System (ADS)
Duignan, Timothy T.; Baer, Marcel D.; Schenter, Gregory K.; Mundy, Chistopher J.
2017-10-01
Determining the solvation free energies of single ions in water is one of the most fundamental problems in physical chemistry and yet many unresolved questions remain. In particular, the ability to decompose the solvation free energy into simple and intuitive contributions will have important implications for models of electrolyte solution. Here, we provide definitions of the various types of single ion solvation free energies based on different simulation protocols. We calculate solvation free energies of charged hard spheres using density functional theory interaction potentials with molecular dynamics simulation and isolate the effects of charge and cavitation, comparing to the Born (linear response) model. We show that using uncorrected Ewald summation leads to unphysical values for the single ion solvation free energy and that charging free energies for cations are approximately linear as a function of charge but that there is a small non-linearity for small anions. The charge hydration asymmetry for hard spheres, determined with quantum mechanics, is much larger than for the analogous real ions. This suggests that real ions, particularly anions, are significantly more complex than simple charged hard spheres, a commonly employed representation.
Simulation and study of stratified flows around finite bodies
NASA Astrophysics Data System (ADS)
Gushchin, V. A.; Matyushin, P. V.
2016-06-01
The flows past a sphere and a square cylinder of diameter d moving horizontally at the velocity U in a linearly density-stratified viscous incompressible fluid are studied. The flows are described by the Navier-Stokes equations in the Boussinesq approximation. Variations in the spatial vortex structure of the flows are analyzed in detail in a wide range of dimensionless parameters (such as the Reynolds number Re = Ud/ ν and the internal Froude number Fr = U/( Nd), where ν is the kinematic viscosity and N is the buoyancy frequency) by applying mathematical simulation (on supercomputers of Joint Supercomputer Center of the Russian Academy of Sciences) and three-dimensional flow visualization. At 0.005 < Fr < 100, the classification of flow regimes for the sphere (for 1 < Re < 500) and for the cylinder (for 1 < Re < 200) is improved. At Fr = 0 (i.e., at U = 0), the problem of diffusion-induced flow past a sphere leading to the formation of horizontal density layers near the sphere's upper and lower poles is considered. At Fr = 0.1 and Re = 50, the formation of a steady flow past a square cylinder with wavy hanging density layers in the wake is studied in detail.
Acceptance of the Theory of Evolution in America: Louis Agassiz vs. Asa Gray
ERIC Educational Resources Information Center
Wolfe, Elaine Claire Daughetee
1975-01-01
Provides some background information on the contributions of Louis Agassiz and Asa Gray to the history of American science as these two men disagreed concerning the ideas in Darwin's "The Orgin of Species." (PB)
McKenzie, S; Doe, W; Buffinton, G
1999-01-01
Background—Reactive oxygen and nitrogen derived species produced by activated neutrophils have been implicated in the damage of mucosal proteins including the inhibition of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in the active inflammatory lesion in patients with inflammatory bowel disease (IBD). This study investigated the efficacy of currently used IBD therapeutics to prevent injury mediated by reactive oxygen and nitrogen derived species. Methods—GAPDH activity of human colon epithelial cells was used as a sensitive indicator of injury produced by reactive oxygen and nitrogen derived species. HCT116 cells (106/ml phosphate buffered saline; 37°C) were incubated in the presence of 5-aminosalicylic acid (5-ASA), 6-mercaptopurine, methylprednisolone, or metronidazole before exposure to H2O2, HOCl, or NO in vitro. HCT116 cell GAPDH enzyme activity was determined by standard procedures. Cell free reactions between 5-ASA and HOCl were analysed by spectrophotometry and fluorimetry to characterise the mechanism of oxidant scavenging. Results—GAPDH activity of HCT116 cells was inhibited by the oxidants tested: the concentration that produced 50% inhibition (IC50) was 44.5 (2.1) µM for HOCl, 379.8 (21.3) µM for H2O2, and 685.8 (103.8) µM for NO (means (SEM)). 5-ASA was the only therapeutic compound tested to show efficacy (p<0.05) against HOCl mediated inhibition of enzyme activity; however, it was ineffective against H2O2 and NO mediated inhibition of GAPDH. Methylprednisolone, metronidazole, and the thiol-containing 6-mercaptopurine were ineffective against all oxidants. Studies at ratios of HOCl:5-ASA achievable in the mucosa showed direct scavenging to be the mechanism of protection of GAPDH activity. Mixing 5-ASA and HOCl before addition to the cells resulted in significantly greater protection of GAPDH activity than when HOCl was added to cells preincubated with 5-ASA. The addition of 5-ASA after HOCl exposure did not restore GAPDH activity. Conclusions—Therapies based on 5-ASA may play a direct role in scavenging the potent neutrophil oxidant HOCl, thereby protecting mucosal GAPDH from oxidative inhibition. These findings suggest that strategies for the further development of new HOCl scavenging compounds may be useful in the treatment of IBD. Keywords: 5-aminosalicylic acid; 6-mercaptopurine; prednisolone; metronidazole; oxidants; glyceraldehyde-3-phosphate dehydrogenase PMID:9895376
Welham, Simon J M; Sparrow, Alexander J; Gardner, David S; Elmes, Matthew J
2017-01-06
To evaluate the effects of the non-selective, non-steroidal anti-inflammatory drug (NSAID) acetylsalicylic acid (ASA), on ex vivo embryonic kidney growth and development. Pairs of fetal mouse kidneys at embryonic day 12.5 were cultured ex vivo in increasing concentrations of ASA (0.04-0.4 mg/mL) for up to 7 d. One organ from each pair was grown in control media and was used as the internal control for the experimental contralateral organ. In some experiments, organs were treated with ASA for 48 h and then transferred either to control media alone or control media containing 10 μmol/L prostaglandin E 2 (PGE 2 ) for a further 5 d. Fetal kidneys were additionally obtained from prostaglandin synthase 2 homozygous null or heterozygous (PTGS2 -/- and PTGS2 -/+ ) embryos and grown in culture. Kidney cross-sectional area was used to determine treatment effects on kidney growth. Whole-mount labelling to fluorescently detect laminin enabled crude determination of epithelial branching using confocal microscopy. Increasing ASA concentration (0.1, 0.2 and 0.4 mg/mL) significantly inhibited metanephric growth ( P < 0.05). After 7 d of culture, exposure to 0.2 mg/mL and 0.4 mg/mL reduced organ size to 53% and 23% of control organ size respectively ( P < 0.01). Addition of 10 μmol/L PGE 2 to culture media after exposure to 0.2 mg/mL ASA for 48 h resulted in a return of growth area to control levels. Application of control media alone after cessation of ASA exposure showed no benefit on kidney growth. Despite the apparent recovery of growth area with 10 μmol/L PGE 2 , no obvious renal tubular structures were formed. The number of epithelial tips generated after 48 h exposure to ASA was reduced by 40% (0.2 mg/mL; P < 0.05) and 47% (0.4 mg/mL; P < 0.01). Finally, growth of PTGS2 -/- and PTGS2 +/- kidneys in organ culture showed no differences, indicating that PTGS2 derived PGE 2 may at best have a minor role. ASA reduces early renal growth and development but the role of prostaglandins in this may be minor.
Patient survival and surgical re-intervention predictors for intracapsular hip fractures.
González Quevedo, David; Mariño, Iskandar Tamimi; Sánchez Siles, Juan Manuel; Escribano, Esther Romero; Granero Molina, Esther Judith; Enrique, David Bautista; Smoljanović, Tomislav; Pareja, Francisco Villanueva
2017-08-01
Choosing between total hip replacement (THR) and partial hip replacement (PHR) for patients with intracapsular hip fractures is often based on subjective factors. Predicting the survival of these patients and risk of surgical re-intervention is essential to select the most adequate implant. We conducted a retrospective cohort study on mortality of patients over 70 years with intracapsular hip fractures who were treated between January 2010 and December 2013, with either PHR or THR. Patients' information was withdrawn from our local computerized database. The age-adjusted Charlson comorbidity index (ACCI) and American Society of Anesthesiologists (ASA) score were calculated for all patients. The patients were followed for 2 years after surgery. Survival and surgical re-intervention rates were compared between the two groups using a Multivariate Cox proportional hazard model. A total of 356 individuals were included in this study. At 2 years of follow-up, 221 (74.4%) of the patients with ACCI score≤7 were still alive, in contrast to only 20 (29.0%) of those with ACCI score>7. In addition, 201 (76.2%) of the patients with ASA score≤3 were still alive after 2 years, compared to 30 (32.6%) of individuals with ASA >3. Patients with the ACCI score>7, and ASA score>3 had a significant increase in all-cause 2-year mortality (adjusted hazard ratio of 3.2, 95% CI 2.2-4.6; and 3.12, 95% CI 2.2-4.5, respectively). Patients with an ASA score>3 had a quasi-significant increase in the re-intervention risk (adjusted hazard ratio 2.2, 95% CI 1.0-5.1). The sensitivity, specificity, positive predictive value and negative predictive values of ACCI in predicting 2-year mortality were 39.2%, 91.1%, 71%, and 74.4%, respectively. On the other hand, the sensitivity, specificity, positive predictive value and negative predictive values of ASA score in predicting 2-year mortality were 49.6%, 79.1%, 67.4%, and 76.1%, respectively. Both ACCI and ASA scales were able to predict the 2-year survival of patients with intracapsular hip fractures. The ASA scale was also able to predict the risk of re-intervention in these patients. Copyright © 2017 Elsevier Ltd. All rights reserved.
Suppression of insolation heating induced by electromagnetic scatteringdue to fine spheres
NASA Astrophysics Data System (ADS)
Horie, J.; Mikada, H.; Goto, T.; Takekawa, J.; Manaka, Y.; Taniguchi, K.; Ashida, Y.
2013-12-01
The 2011 off the Pacific coast of Tohoku Earthquake, i.e., the greatest earthquake in the Japanese history, and the successive disaster at the Fukushima Daiichi Nuclear Power Plant have caused a fatal electric power shortage problem in summer in 2011. It is of key importance to reduce electricity demand and to save the energy. About one third of the total electricity demand at the peak consumption in summer is for the air-conditioning in the household and office sectors in Japan. It is, therefore, necessary to think deliberately of the reduction of electric power demand for air-conditioning. In fact, the temperature of materials rises when they are exposed to the sunlight (insolation heating) in particular in summer and the air-conditioning would become necessary for restoring the comfort in insolated housings. The energy for the air-conditioning is spent to pump out the heat changed in the materials of the insolated housings and would be proportional to the temperature to lower down. It is, therefore, clear that the reduction of the energy for the air-conditioning would strongly depend on relaxation of temperature rise or the insulation of insolated materials. Insolation heating could be suppressed when the materials are coated with paint admixed with fine silica spheres (insulating paint). By coating buildings' walls and roofs with such paint, the temperature of interior rooms could be kept lower without air-conditioning. These insulation effects are well known and have been utilized in the past, but have hardly been analyzed theoretically yet. Theoretical analysis would greatly enhance the effects of the suppression of insolation heating. In preceding studies, Ohkawa et al.(2009; 2011) and Mikada et al.(2011) focused on the electromagnetic wave scattering induced by fine spheres and developed the analytical method using superposition of scattered waves from each sphere (the first Born approximation), and indicated that the size of the spheres is one of the parameters affecting the light intensity transmitted through the paint. However, the rigorous results, not using such approximation or considering other parameters than the size of spheres, are still unknown. Such rigorous solution is necessary to find the best structure of the paint for insulating phenomena. In this study, we consider fine spheres randomly distributed in a paint layer coating a material, and analyze its scattering characteristics using the Monte Carlo ray tracing method based on the Mie theory. Three layers (air, paint and iron) are first assumed and a number of photons incident on the paint layer. The optical paths of photons are successively traced. We use their ratio between the number of reflected and transmitted photons and their phases in order toestimate the intensity of near-infrared sunlight that reaches the material (transmission intensity). As a result, it is found that the sphere radius should be less than 0.5 μm and the refractive index of sphere is less than 1.45 if we want to decrease the transmission intensity to less than about 0.1. We conclude that the introduction of the Monte Carlo simulation has led us to a quantitative analysis of the insulation effects caused by electromagnetic scattering and to find the optimum size and material of spheres to be admixed with paint.
Wittig-Wells, Deborah; Higgins, Melinda; Davis, Erica; Johnson, Ifeya; Louis, Latalya; Mason, Olga; Samms-McPherson, Jacqueline; Sims, Sandra; Jacob, Ani
2015-01-01
Patient education for the use and administration of aspirin (ASA) as an anticoagulant may be deficient. To pilot a knowledge assessment tool regarding the use of aspirin (ASA) as an anticoagulant and to evaluate the impact of a focused approach for discharge teaching. One-group pretest-posttest pilot study. Convenience sample of patients hospitalized for total knee and total hip arthroplasty. Researcher developed ASA quiz. Focused education on aspirin as an anticoagulant. There was a statistically significant improvement in knowledge (Wilcoxon rank sum test Z = 3.880, p < .001).
General Anesthesia Time for Pediatric Dental Cases
Forsyth, Anna R.; Seminario, Ana Lucia; Scott, JoAnna; Berg, Joel; Ivanova, Iskra; Lee, Helen
2012-01-01
Purpose The purpose of this study was to describe the use of operating room (OR) time for pediatric dental procedures performed under general anesthesia (GA) at a regional children’s hospital over a 2-year period. Methods A cross-sectional review of a pediatric dental GA records was performed at Seattle Children’s Hospital. Data were collected for 709 0- to 21-year-old patients from January 2008 to December 2009. Demographic data, dental and anesthesia operator types, and procedures were recorded. Utilization of OR time was analyzed. Results The mean age of patients was 7.1 years (±4.2 SD), and 58% were male. Distribution by American Society of Anesthesiology (ASA) classifications were: ASA I 226 (32%); ASA II 316 (45%); ASA III 167 (24%). Cases finished earlier than the scheduled time by an average of 14 minutes (±28). Overrun time was significantly associated with: patient age (P=.01); ASA classification (P=.006); treatment type (P<.001); number of teeth treated (P<.001); and dentist operator type (P=.005). Conclusions Overall, 73% of dental procedures under GA finished early or on time. Significant variables included patient age, medical status, treatment type and extent, and dentist operator type. Assessing factors that impact the time needed in GA may enhance efficiency for pediatric dental procedures. PMID:23211897
Hydraulic forces contribute to left ventricular diastolic filling
Maksuti, Elira; Carlsson, Marcus; Arheden, Håkan; Kovács, Sándor J.; Broomé, Michael; Ugander, Martin
2017-01-01
Myocardial active relaxation and restoring forces are known determinants of left ventricular (LV) diastolic function. We hypothesize the existence of an additional mechanism involved in LV filling, namely, a hydraulic force contributing to the longitudinal motion of the atrioventricular (AV) plane. A prerequisite for the presence of a net hydraulic force during diastole is that the atrial short-axis area (ASA) is smaller than the ventricular short-axis area (VSA). We aimed (a) to illustrate this mechanism in an analogous physical model, (b) to measure the ASA and VSA throughout the cardiac cycle in healthy volunteers using cardiovascular magnetic resonance imaging, and (c) to calculate the magnitude of the hydraulic force. The physical model illustrated that the anatomical difference between ASA and VSA provides the basis for generating a hydraulic force during diastole. In volunteers, VSA was greater than ASA during 75–100% of diastole. The hydraulic force was estimated to be 10–60% of the peak driving force of LV filling (1–3 N vs 5–10 N). Hydraulic forces are a consequence of left heart anatomy and aid LV diastolic filling. These findings suggest that the relationship between ASA and VSA, and the associated hydraulic force, should be considered when characterizing diastolic function and dysfunction. PMID:28256604
Gesoğlu, Mehmet; Güneyisi, Erhan; Mahmood, Swara Fuad; Öz, Hatice Öznur; Mermerdaş, Kasım
2012-10-15
Ground granulated blast furnace slag (GGBFS), a by-product from iron industry, was recycled as artificial coarse aggregate through cold bonding pelletization process. The artificial slag aggregates (ASA) replaced partially the natural coarse aggregates in production of self-compacting concrete (SCC). Moreover, as being one of the most widely used mineral admixtures in concrete industry, fly ash (FA) was incorporated as a part of total binder content to impart desired fluidity to SCCs. A total of six concrete mixtures having various ASA replacement levels (0%, 20%, 40%, 60%, and 100%) were designed with a water-to-binder (w/b) ratio of 0.32. Fresh properties of self-compacting concretes (SCC) were observed through slump flow time, flow diameter, V-funnel flow time, and L-box filling height ratio. Compressive strength of hardened SCCs was also determined at 28 days of curing. It was observed that increasing the replacement level of ASA resulted in decrease in the amount of superplasticizer to achieve a constant slump flow diameter. Moreover, passing ability and viscosity of SCC's enhanced with increasing the amount of ASA in the concrete. The maximum compressive strength was achieved for the SCC having 60% ASA replacement. Copyright © 2012 Elsevier B.V. All rights reserved.
Diagnosis and classification of autoimmune orchitis.
Silva, C A; Cocuzza, M; Carvalho, J F; Bonfá, E
2014-01-01
Autoimmune orchitis is characterized by testis inflammation and the presence of specific antisperm antibodies (ASA). It is classified in two categories. Primary autoimmune orchitis is defined by infertility and asymptomatic orchitis associated with ASA (100%) directed to the basement membrane or seminiferous tubules in infertile men, without any systemic disease and usually asymptomatic. Secondary autoimmune orchitis is characterized by symptomatic orchitis and/or testicular vasculiti`s associated with a systemic autoimmune disease, particularly vasculitis. These patients typically demonstrate testicular pain, erythema and/or swelling. ASA in secondary autoimmune orchitis have been reported in up to 50% of patients, especially in systemic lupus erythematosus patients. The pathogenesis of primary as well as secondary autoimmune orchitis is still unknown. Although the etiology is likely to be multifactorial, testicular inflammation, infection or trauma may induce T cell response with pro-inflammatory cytokine production with a consequent blood-testis-barrier permeability alteration, ASA production and apoptosis of spermatocytes and spermatids. ASA is known to cause immobilization and/or agglutination of spermatozoa, which may block sperm-egg interaction resulting in infertility. Assisted reproduction has been used as an efficient option in primary cases and immunosuppressive therapy for secondary autoimmune orchitis, although there is no double-blind, randomized trial to confirm the efficacy of any treatment regimens for these conditions. Copyright © 2014 Elsevier B.V. All rights reserved.
Kirkpatrick, Sharon I; Gilsing, Anne M; Hobin, Erin; Solbak, Nathan M; Wallace, Angela; Haines, Jess; Mayhew, Alexandra J; Orr, Sarah K; Raina, Parminder; Robson, Paula J; Sacco, Jocelyn E; Whelan, Heather K
2017-01-31
With technological innovation, comprehensive dietary intake data can be collected in a wide range of studies and settings. The Automated Self-Administered 24-hour (ASA24) Dietary Assessment Tool is a web-based system that guides respondents through 24-h recalls. The purpose of this paper is to describe lessons learned from five studies that assessed the feasibility and validity of ASA24 for capturing recall data among several population subgroups in Canada. These studies were conducted within a childcare setting (preschool children with reporting by parents), in public schools (children in grades 5-8; aged 10-13 years), and with community-based samples drawn from existing cohorts of adults and older adults. Themes emerged across studies regarding receptivity to completing ASA24, user experiences with the interface, and practical considerations for different populations. Overall, we found high acceptance of ASA24 among these diverse samples. However, the ASA24 interface was not intuitive for some participants, particularly young children and older adults. As well, technological challenges were encountered. These observations underscore the importance of piloting protocols using online tools, as well as consideration of the potential need for tailored resources to support study participants. Lessons gleaned can inform the effective use of technology-enabled dietary assessment tools in research.
Acetylsalicylic acid is compounding to antiplatelet effect of C-reactive protein.
Boncler, Magdalena; Luzak, Boguslawa; Rozalski, Marcin; Golanski, Jacek; Rychlik, Blazej; Watala, Cezary
2007-01-01
The contribution of inflammatory process to the modulation of platelet response to acetylsalicylic acid (ASA) remains obscure. In our study, we examined the in vitro effect of C-reactive protein (CRP) on the ASA-mediated inhibition of collagen-stimulated platelet reactivity. Influence of CRP on platelet responsiveness to ASA was analysed using classical turbidimetric aggregation and flow cytometry. When acting alone, both C-reactive protein and ASA inhibited collagen-dependent platelet aggregation and reduced the expressions of two platelet surface membrane activation markers: P-selectin and activated GPIIbIIIa complex. Compared to the effects observed for ASA alone, the simultaneous action of both agents lead to further reductions in platelet aggregation (by 56.7+/-1.0% vs. 14.9+/-0.6%, p<0.0001) and lowered the expressions of platelet surface membrane P-selectin (by 72.1+/-5.3% vs. 65.0+/-6.0%, p<0.01) and activated GPIIbIIIa (by 67.0+/-5.6% vs. 47.7+/-8.3%, p<0.01). In general, our findings showed for the first time the augmenting effect of native C-reactive protein in the antiplatelet action of acetylsalicylic acid. Thus, we conclude that the effectiveness of aspirin therapy may strongly depend upon the presence of native CRP in circulation.
HICKEY, Jane; SAUNDERS, Jean; DAVERN, Peter
2015-01-01
A telephone survey was conducted among a sample of managers (n=30) in Ireland who had previously commissioned an asbestos survey in their workplace buildings. The aims of the telephone survey were to examine the extent to which managers had completed Asbestos Safety Awareness (ASA) training, and to assess how such training might influence (i) their instinctive thoughts on asbestos, and (ii) their approach to aspects of asbestos management within their buildings. Managers’ motivations for commissioning the asbestos survey were also identified. The study found that ASA-trained managers (n=11) were not significantly more likely to work in larger organisations or in organisations which operated an accredited management system. Though ASA-trained managers’ instinctive thoughts on asbestos were of a slightly poorer technical quality compared with those of non-ASA-trained managers, they were still significantly more cognisant of their responsibilities towards those of their employees at specific risk of asbestos exposure. Most managers (n=28) commissioned the asbestos survey to satisfy a pre-requisite of external contractors for commencing refurbishment/demolition work in their buildings. Given its potential to positively influence the occupational management of asbestos, the authors recommend the general promotion of suitably tailored ASA-training programmes among building managers and external contractors alike. PMID:25914070
Hickey, Jane; Saunders, Jean; Davern, Peter
2015-01-01
A telephone survey was conducted among a sample of managers (n=30) in Ireland who had previously commissioned an asbestos survey in their workplace buildings. The aims of the telephone survey were to examine the extent to which managers had completed Asbestos Safety Awareness (ASA) training, and to assess how such training might influence (i) their instinctive thoughts on asbestos, and (ii) their approach to aspects of asbestos management within their buildings. Managers' motivations for commissioning the asbestos survey were also identified. The study found that ASA-trained managers (n=11) were not significantly more likely to work in larger organisations or in organisations which operated an accredited management system. Though ASA-trained managers' instinctive thoughts on asbestos were of a slightly poorer technical quality compared with those of non-ASA-trained managers, they were still significantly more cognisant of their responsibilities towards those of their employees at specific risk of asbestos exposure. Most managers (n=28) commissioned the asbestos survey to satisfy a pre-requisite of external contractors for commencing refurbishment/demolition work in their buildings. Given its potential to positively influence the occupational management of asbestos, the authors recommend the general promotion of suitably tailored ASA-training programmes among building managers and external contractors alike.
Tarafder, Sumit; Toukir Ahmed, Md; Iqbal, Sumaiya; Tamjidul Hoque, Md; Sohel Rahman, M
2018-03-14
Accessible surface area (ASA) of a protein residue is an effective feature for protein structure prediction, binding region identification, fold recognition problems etc. Improving the prediction of ASA by the application of effective feature variables is a challenging but explorable task to consider, specially in the field of machine learning. Among the existing predictors of ASA, REGAd 3 p is a highly accurate ASA predictor which is based on regularized exact regression with polynomial kernel of degree 3. In this work, we present a new predictor RBSURFpred, which extends REGAd 3 p on several dimensions by incorporating 58 physicochemical, evolutionary and structural properties into 9-tuple peptides via Chou's general PseAAC, which allowed us to obtain higher accuracies in predicting both real-valued and binary ASA. We have compared RBSURFpred for both real and binary space predictions with state-of-the-art predictors, such as REGAd 3 p and SPIDER2. We also have carried out a rigorous analysis of the performance of RBSURFpred in terms of different amino acids and their properties, and also with biologically relevant case-studies. The performance of RBSURFpred establishes itself as a useful tool for the community. Copyright © 2018 Elsevier Ltd. All rights reserved.
Degl'Innocenti, E; Guidi, L; Pardossi, A; Tognoni, F
2005-12-28
A series of biochemical parameters, including the concentration of total ascorbic acid (ASA(tot)) and the activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and peroxidases (PODs), was investigated during cold storage (72 h at 4 degrees C in the dark) in fresh-cut (minimally processed) leaves of two lettuce (Lactuca sativa L. var. acephala) cultivars differing in the susceptibility to tissue browning: Green Salade Bowl (GSB), susceptible, and Red Salade Bowl (RSB), resistant. The two cultivars showed differences also at the biochemical level. The content in ASA(tot) increased in RSB, as a consequence of increased DHA concentration; conversely, ASA(tot) diminished in GSB, in which ASA was not detectable after 72 h of storage, thus suggesting a disappearance of ascorbate (both ASA and DHA) into nonactive forms. The antioxidant capacity (as determined by using FRAP analysis) decreased significantly during storage in RSB, while a strong increase was observed in GSB. PAL activity increased soon after processing reaching a maximum by 3 h, then it declined to a relatively constant value in RSB, while in GSB it showed a tendency to decrease in the first few hours from harvest and processing. POD activity, at least for chlorogenic acid, increased significantly during storage only in GSB.
Di Lorenzo, G; Pacor, M L; Vignola, A M; Profita, M; Esposito-Pellitteri, M; Biasi, D; Corrocher, R; Caruso, C
2002-12-01
The recovery of mediator metabolites from urine has the potential to provide a rapid, safe, and easily available index of release of mediators. We aimed to determine urinary metabolites of both histamine and leukotrienes (LTs) in patients affected by chronic urticaria (CU). Twenty patients with CU were studied. They were selected on the basis of double-blind placebo-controlled challenge (DBPC) with acetyl salicylic acid (ASA) and food additives. Ten patients (group B) were negative to both challenges. Ten patients (group C) presented urticaria and/or the appearance of angioedema during or 24 h after challenge, with reactions to ASA (five patients) or food additives (five patients). We recruited 15 healthy volunteers as controls (group A). During a second challenge, groups B and C were challenged double-blind with a single dose of ASA, or a specific food additive, or placebo. The healthy group was challenged only with a placebo (talc capsule). Patients in groups B and C were challenged twice: with placebo (as groups B1 and C1) and with ASA (groups B2 and C2) or food additives (C2). Four samples of urine were collected; one during the night before the specific or sham challenge (baseline), and three at 2, 6 and 24 h after the challenge. Urinary methylhistamine (N-MH) and LTE4 were analyzed and normalized for urinary creatinine. For urinary N-MH at baseline, there was a significant difference only between group A and groups B1, B2, C1 and C2 (A vs. B1, P < 0.0001; A vs. B2, P < 0.0001; A vs. C1, P < 0.0001; A vs. C2, P < 0.0001). We detected a significant variation in urinary methylhistamine excretion only in group C2 after 2 h, 6 h and 24 h (P < 0.0001). However, no variations were observed in N-MH excretion rate in the other groups (A, B1, C1) after challenge with placebo, and in B2 after challenge with ASA 20 mg. For urinary LTE4 at baseline no differences were found between the mean values for the different groups. After specific challenge, only C2 patients showed significantly increased excretion rates of urinary LTE4 compared with the other groups challenged with placebo (A, B1, C1), or ASA (B2) (P < 0.0001). No significant correlation was seen between urinary LTE4 and methylhistamine excretion rate in any patients. Our results show that urinary excretion of N-MH and LTE4 is different for CU patients without ASA or food hypersensitivity, compared to those with CU with ASA or food additive hypersensitivity after specific challenge.
Clopidogrel is not associated with major bleeding complications during peripheral arterial surgery
Stone, David H.; Goodney, Philip P.; Schanzer, Andres; Nolan, Brian W.; Adams, Julie E.; Powell, Richard J.; Walsh, Daniel B.; Cronenwett, Jack L.
2017-01-01
Objectives Persistent variation in practice surrounds preoperative clopidogrel management at the time of vascular surgery. While some surgeons preferentially discontinue clopidogrel citing a perceived risk of perioperative bleeding, others will proceed with surgery in patients taking clopidogrel for an appropriate indication. The purpose of this study was to determine whether preoperative clopidogrel use was associated with significant bleeding complications during peripheral arterial surgery. Methods We reviewed a prospective regional vascular surgery registry recorded by 66 surgeons from 15 centers in New England from 2003 to 2009. Preoperative clopidogrel use within 48 hours of surgery was analyzed among patients undergoing carotid endarterectomy (CEA), lower extremity bypass (LEB), endovascular abdominal aortic aneurysm repair (EVAR), and open abdominal aortic aneurysm repair (oAAA). Ruptured AAAs were excluded. Endpoints included postoperative bleeding requiring reoperation, as well as the incidence and volume of blood transfusion. Statistical analysis was performed using analysis of variance, Fisher exact, χ2, and Wilcoxon rank-sum tests. Results Over the study interval, a total of 10,406 patients underwent surgery, including 5264 CEA, 2883 LEB, 1125 EVAR, and 1134 oAAA repair. Antiplatelet use among all patients varied, with 19% (n = 2010) taking no antiplatelet agents, 69% (n = 7132) taking aspirin (ASA) alone, 2.2% (n = 229) taking clopidogrel alone, and 9.7% (n = 1017) taking both ASA and clopidogrel. Clopidogrel alone or as dual antiplatelet therapy was most frequently used prior to CEA and least frequently prior to oAAA group (CEA 16.1%, LEB 9.0%, EVAR 6.5%, oAAA 5%). Reoperation for bleeding was not significantly different among patients based on antiplatelet regimen (none 1.5%, ASA 1.3%, clopidogrel 0.9%, ASA/clopidogrel 1.5%, P = .74). When analyzed by operation type, no difference in reoperation for bleeding was seen across antiplatelet regimens. There was also no difference in the incidence of transfusion among antiplatelet treatment groups (none 18%, ASA 17%, clopidogrel 0%, ASA/clopidogrel 24%, P = .1) and none when analyzed by individual operation type. Among patients who did require transfusion, there was no significant difference in the mean number of units of packed red blood cells required (none 0.7 units, ASA 0.5 units, clopidogrel 0 units, ASA/clopidogrel 0.6 units, P = .1) or when stratified by operation type. Conclusions Patients undergoing peripheral arterial surgery in whom clopidogrel was continued either alone or as part of dual antiplatelet therapy did not have significant bleeding complications compared with patients taking no antiplatelet therapy or ASA alone at the time of surgery. These data suggest that clopidogrel can safely be continued preoperatively in patients with appropriate indications for its use, such as symptomatic carotid disease or recent drug-eluting coronary stents. PMID:21571492