Subcellular SIMS imaging of gadolinium isotopes in human glioblastoma cells treated with a gadolinium containing MRI agent

NASA Astrophysics Data System (ADS)

Smith, Duane R.; Lorey, Daniel R.; Chandra, Subhash

2004-06-01

Neutron capture therapy is an experimental binary radiotherapeutic modality for the treatment of brain tumors such as glioblastoma multiforme. Recently, neutron capture therapy with gadolinium-157 has gained attention, and techniques for studying the subcellular distribution of gadolinium-157 are needed. In this preliminary study, we have been able to image the subcellular distribution of gadolinium-157, as well as the other six naturally abundant isotopes of gadolinium, with SIMS ion microscopy. T98G human glioblastoma cells were treated for 24 h with 25 mg/ml of the metal ion complex diethylenetriaminepentaacetic acid Gd(III) dihydrogen salt hydrate (Gd-DTPA). Gd-DTPA is a contrast enhancing agent used for MRI of brain tumors, blood-brain barrier impairment, diseases of the central nervous system, etc. A highly heterogeneous subcellular distribution was observed for gadolinium-157. The nuclei in each cell were distinctly lower in gadolinium-157 than in the cytoplasm. Even within the cytoplasm the gadolinium-157 was heterogeneously distributed. The other six naturally abundant isotopes of gadolinium were imaged from the same cells and exhibited a subcellular distribution consistent with that observed for gadolinium-157. These observations indicate that SIMS ion microscopy may be a viable approach for subcellular studies of gadolinium containing neutron capture therapy drugs and may even play a major role in the development and validation of new gadolinium contrast enhancing agents for diagnostic MRI applications.

Modulation of channel activity and gadolinium block of MscL by static magnetic fields.

PubMed

Petrov, Evgeny; Martinac, Boris

2007-02-01

The magnetic field of the Earth has for long been known to influence the behaviour and orientation of a variety of living organisms. Experimental studies of the magnetic sense have, however, been impaired by the lack of a plausible cellular and/or molecular mechanism providing meaningful explanation for detection of magnetic fields by these organisms. Recently, mechanosensitive (MS) ion channels have been implied to play a role in magnetoreception. In this study we have investigated the effect of static magnetic fields (SMFs) of moderate intensity on the activity and gadolinium block of MscL, the bacterial MS channel of large conductance, which has served as a model channel to study the basic physical principles of mechanosensory transduction in living cells. In addition to showing that direct application of the magnetic field decreased the activity of the MscL channel, our study demonstrates for the first time that SMFs can reverse the effect of gadolinium, a well-known blocker of MS channels. The results of our study are consistent with a notion that (1) the effects of SMFs on the MscL channels may result from changes in physical properties of the lipid bilayer due to diamagnetic anisotropy of phospholipid molecules and consequently (2) cooperative superdiamagnetism of phospholipid molecules under influence of SMFs could cause displacement of Gd(3+) ions from the membrane bilayer and thus remove the MscL channel block.

Removal of gadolinium-based contrast agents: adsorption on activated carbon.

PubMed

Elizalde-González, María P; García-Díaz, Esmeralda; González-Perea, Mario; Mattusch, Jürgen

2017-03-01

Three carbon samples were employed in this work, including commercial (1690 m 2  g -1 ), activated carbon prepared from guava seeds (637 m 2  g -1 ), and activated carbon prepared from avocado kernel (1068 m 2  g -1 ), to study the adsorption of the following gadolinium-based contrast agents (GBCAs): gadoterate meglumine Dotarem®, gadopentetate dimeglumine Magnevist®, and gadoxetate disodium Primovist®. The activation conditions with H 3 PO 4 were optimized using a Taguchi methodology to obtain mesoporous materials. The best removal efficiency by square meter in a batch system in aqueous solution and model urine was achieved by avocado kernel carbon, in which mesoporosity prevails over microporosity. The kinetic adsorption curves were described by a pseudo-second-order equation, and the adsorption isotherms in the concentration range 0.5-6 mM fit the Freundlich equation. The chemical characterization of the surfaces shows that materials with a greater amount of phenolic functional groups adsorb the GBCA better. Adsorption strongly depends on the pH due to the combination of the following factors: contrast agent protonated forms and carbon surface charge. The tested carbon samples were able to adsorb 70-90% of GBCA in aqueous solution and less in model urine. This research proposes a method for the elimination of GBCA from patient urine before its discharge into wastewater.

Analysis of Blood Gadolinium in an Isotope Geochemist Following Contrast MRI

NASA Astrophysics Data System (ADS)

Wasylenki, L. E.

2011-12-01

Normal brain tissue does not have blood flowing throughout it; instead oxygen diffuses across a blood-brain barrier in order to oxygenate brain cells. Brain tumors, however, do grow blood supplies, so an abnormal distribution of blood in the brain is a key indicator of abnormal cell growth. But how is the distribution of blood in inside the brain observed? The lanthanide ion gadolinium(III) has unpaired 5f-shell electrons and is thus paramagnetic. As such, the presence of Gd causes the nuclei of nearby atoms to relax more quickly when excited to high-energy spin states by pulses of radio-frequency energy than they would without Gd nearby. The signal in magnetic resonance imaging correlates with this nuclear spin relaxation time, so gadolinium's presence in certain body tissues makes those tissues appear as bright areas on MRI images. Gadolinium is therefore commonly injected intravenously just prior to MRI imaging, so that the distribution of blood in and around the brain can be mapped. Gadolinium as a free ion is toxic, so it is injected in a relatively inert form, often as gadoversetamide, in which Gd is tightly bound in nine-fold coordination with N, C, and O. This compound is removed from the blood by the kidneys at a rate that is fast compared to the rate of breakdown of this compound in the blood, thus preventing release of toxic Gd in the bloodstream. But how quickly can the kidneys of an isotope geochemist remove Gd from blood? In this experiment, a single isotope geochemist's wristwatch was synchronized with that of the MRI technician and then left in a dressing room with all other magnetically susceptible objects until after the MRI. The time of intravenous injection of gadoversetamide into the isotopist was recorded by the technician and later transmitted verbally to the isotopist. Following the MRI session, blood samples were collected by self-fingerprick, in a Class 100 trace metal clean lab, from 47 to 281 minutes after intravenous injection. For each timepoint, approximately 300 microliters of blood were transferred by acid-washed pipette to an acid-washed, Teflon, screw-cap vial and weighed. Samples were digested with hot, concentrated nitric acid and 30% hydrogen peroxide, dried down, and redissolved in 0.32 M nitric acid. Gd concentrations were measured by quadrupole ICP-MS, at masses 152, 154, 155, 156, 157, 158, and 160, using yttrium (mass 89) and bismuth (mass 209) as internal standards to normalize plasma variations during the run. Results indicate decreasing blood Gd concentrations, from 35.8 parts per million by weight at 47 minutes after injection to 7.5 parts per million at 281 minutes. The data have a near-perfect fit to an exponential decay curve with half-life of 105 minutes, demonstrating that renal filtration of gadoversetamide is a first-order reaction in at least one isotope geochemist.

Use of gadolinium-based magnetic resonance imaging contrast agents and awareness of brain gadolinium deposition among pediatric providers in North America.

PubMed

Mithal, Leena B; Patel, Payal S; Mithal, Divakar; Palac, Hannah L; Rozenfeld, Michael N

2017-05-01

Numerous recent articles have reported brain gadolinium deposition when using linear but not macrocyclic gadolinium-based contrast agents (GBCAs). To determine the current landscape of gadolinium use among pediatric institutions and the knowledge base of radiologists and referring providers with regard to GBCAs and brain gadolinium deposition. We e-mailed voluntary closed surveys to 5,390 physicians in various pediatric professional societies between January 2016 and March 2016. We used chi-square and Fisher exact tests to compare response distributions among specialties. We found that 80% of surveyed pediatric hospitals use macrocyclic contrast agents. In the last year, 58% switched their agent, most commonly to gadoterate meglumine, with the most common reason being brain gadolinium deposition. Furthermore, surveys indicated that 23% of hospitals are considering switching, and, of these, 83% would switch to gadoterate meglumine; the most common reasons were brain gadolinium deposition and safety. Radiologists were more aware of brain gadolinium deposition than non-radiologist physicians (87% vs. 26%; P<0.0001). Radiologists and referring providers expressed similar levels of concern (95% and 89%). Twelve percent of radiologists and 2% of referring providers reported patients asking about brain gadolinium deposition. Radiologists were significantly more comfortable addressing patient inquiries than referring pediatric physicians (48% vs. 6%; P<0.0001). The number of MRIs requested by referring pediatric physicians correlated with their knowledge of brain gadolinium deposition, contrast agent used by their hospital, and comfort discussing brain gadolinium deposition with patients (P<0.0001). Since the discovery of brain gadolinium deposition, many pediatric hospitals have switched to or plan to switch to a more stable macrocyclic MR contrast agent, most commonly gadoterate meglumine. Despite this, there is need for substantial further education of radiologists and referring pediatric providers regarding GBCAs and brain gadolinium deposition.

Structural and magnetic phase transitions in gadolinium under high pressures and low temperatures

DOE PAGES

Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.; ...

2014-11-07

High pressure structural transition studies have been carried out on rare earth metal gadolinium in a diamond anvil cell at room temperature to 169 GPa. Gadolinium has been compressed to 38% of its initial volume at this pressure. With increasing pressure, a crystal structure sequence of hcp → Smtype→ dhcp → fcc → dfcc → monoclinic has been observed in our studies on gadolinium. The measured equation of state of gadolinium is presented to 169 GPa at ambient temperature. Magnetic ordering temperature of gadolinium has been studied using designer diamond anvils to a pressure of 25 GP and a temperaturemore » of 10 K. The magnetic ordering temperature has been determined from the four-point electrical resistivity measurements carried out on gadolinium. Furthermore, our experiments show that the magnetic transition temperature decreases with increasing pressure to 19 GPa and then increases when gadolinium is subjected to higher pressures.« less

Magnetic resonance characteristics and susceptibility weighted imaging of the brain in gadolinium encephalopathy.

PubMed

Samardzic, Dejan; Thamburaj, Krishnamoorthy

2015-01-01

To report the brain imaging features on magnetic resonance imaging (MRI) in inadvertent intrathecal gadolinium administration. A 67-year-old female with gadolinium encephalopathy from inadvertent high dose intrathecal gadolinium administration during an epidural steroid injection was studied with multisequence 3T MRI. T1-weighted imaging shows pseudo-T2 appearance with diffusion of gadolinium into the brain parenchyma, olivary bodies, and membranous labyrinth. Nulling of cerebrospinal fluid (CSF) signal is absent on fluid attenuation recovery (FLAIR). Susceptibility-weighted imaging (SWI) demonstrates features similar to subarachnoid hemorrhage. CT may demonstrate a pseudo-cerebral edema pattern given the high attenuation characteristics of gadolinium. Intrathecal gadolinium demonstrates characteristic imaging features on MRI of the brain and may mimic subarachnoid hemorrhage on susceptibility-weighted imaging. Identifying high dose gadolinium within the CSF spaces on MRI is essential to avoid diagnostic and therapeutic errors. Copyright © 2013 by the American Society of Neuroimaging.

Structural and magnetic phase transitions in gadolinium under high pressures and low temperatures

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

Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.

High pressure structural transition studies have been carried out on rare earth metal gadolinium in a diamond anvil cell at room temperature to 169 GPa. Gadolinium has been compressed to 38% of its initial volume at this pressure. With increasing pressure, a crystal structure sequence of hcp → Smtype→ dhcp → fcc → dfcc → monoclinic has been observed in our studies on gadolinium. The measured equation of state of gadolinium is presented to 169 GPa at ambient temperature. Magnetic ordering temperature of gadolinium has been studied using designer diamond anvils to a pressure of 25 GP and a temperaturemore » of 10 K. The magnetic ordering temperature has been determined from the four-point electrical resistivity measurements carried out on gadolinium. Furthermore, our experiments show that the magnetic transition temperature decreases with increasing pressure to 19 GPa and then increases when gadolinium is subjected to higher pressures.« less

Structural and magnetic phase transitions in gadolinium under high pressures and low temperatures

NASA Astrophysics Data System (ADS)

Samudrala, Gopi K.; Tsoi, Georgiy M.; Weir, Samuel T.; Vohra, Yogesh K.

2014-10-01

High pressure structural transition studies have been carried out on rare earth metal gadolinium in a diamond anvil cell at room temperature to 169 GPa. Gadolinium has been compressed to 38% of its initial volume at this pressure. With increasing pressure, a crystal structure sequence of hcp → Sm-type → dhcp → fcc → dfcc → monoclinic has been observed in our studies on gadolinium. The measured equation of state of gadolinium is presented to 169 GPa at ambient temperature. Magnetic ordering temperature of gadolinium has been studied using designer diamond anvils to a pressure of 25 GPa and a temperature of 10 K. The magnetic ordering temperature has been determined from the four-point electrical resistivity measurements carried out on gadolinium. Our experiments show that the magnetic transition temperature decreases with increasing pressure to 19 GPa and then increases when gadolinium is subjected to higher pressures.

Two-year survey of specific hospital wastewater treatment and its impact on pharmaceutical discharges.

PubMed

Wiest, Laure; Chonova, Teofana; Bergé, Alexandre; Baudot, Robert; Bessueille-Barbier, Frédérique; Ayouni-Derouiche, Linda; Vulliet, Emmanuelle

2018-04-01

It is well known that pharmaceuticals are not completely removed by conventional activated sludge wastewater treatment plants. Hospital effluents are of major concern, as they present high concentrations of pharmaceutically active compounds. Despite this, these specific effluents are usually co-treated with domestic wastewaters. Separate treatment has been recommended. However, there is a lack of information concerning the efficiency of separate hospital wastewater treatment by activated sludge, especially on the removal of pharmaceuticals. In this context, this article presents the results of a 2-year monitoring of conventional parameters, surfactants, gadolinium, and 13 pharmaceuticals on the specific study site SIPIBEL. This site allows the characterization of urban and hospital wastewaters and their separate treatment using the same process. Flow proportional sampling, solid-phase extraction, and liquid chromatography coupled with tandem mass spectrometry were used in order to obtain accurate data and limits of quantification consistent with ultra-trace detection. Thanks to these consolidated data, an in-depth characterization of urban and hospital wastewaters was realized, as well as a comparison of treatment efficiency between both effluents. Higher concentrations of organic carbon, AOX, phosphates, gadolinium, paracetamol, ketoprofen, and antibiotics were observed in hospital wastewaters compared to urban wastewaters. Globally higher removals were observed in the hospital wastewater treatment plant, and some parameters were shown to be of high importance regarding removal efficiencies: hydraulic retention time, redox conditions, and ambient temperature. Eleven pharmaceuticals were still quantified at relevant concentrations in hospital and urban wastewaters after treatment (e.g., up to 1 μg/L for sulfamethoxazole). However, as the urban flow was about 37 times higher than the hospital flow, the hospital contribution appeared relatively low compared to domestic discharges. Thanks to the SIPIBEL site, data obtained from this 2-year program are useful to evaluate the relevance of separate hospital wastewater treatment.

Gadolinium-based contrast agent toxicity: a review of known and proposed mechanisms.

PubMed

Rogosnitzky, Moshe; Branch, Stacy

2016-06-01

Gadolinium chelates are widely used as contrast media for magnetic resonance imaging. The approved gadolinium-based contrast agents (GBCAs) have historically been considered safe and well tolerated when used at recommended dosing levels. However, for nearly a decade, an association between GBCA administration and the development of nephrogenic systemic fibrosis (NSF) has been recognized in patients with severe renal impairment. This has led to modifications in clinical practices aimed at reducing the potential and incidence of NSF development. Newer reports have emerged regarding the accumulation of gadolinium in various tissues of patients who do not have renal impairment, including bone, brain, and kidneys. Despite the observations of gadolinium accumulation in tissues regardless of renal function, very limited clinical data regarding the potential for and mechanisms of toxicity is available. This significant gap in knowledge warrants retrospective cohort study efforts, as well as prospective studies that involve gadolinium ion (Gd(3+)) testing in patients exposed to GBCA. This review examines the potential biochemical and molecular basis of gadolinium toxicity, possible clinical significance of gadolinium tissue retention and accumulation, and methods that can limit gadolinium body burden.

6 Mcps photon-counting X-ray computed tomography system using a 25 mm/s-scan linear LSO-MPPC detector and its application to gadolinium imaging

NASA Astrophysics Data System (ADS)

Sato, Eiichi; Oda, Yasuyuki; Abudurexiti, Abulajiang; Hagiwara, Osahiko; Matsukiyo, Hiroshi; Osawa, Akihiro; Enomoto, Toshiyuki; Watanabe, Manabu; Kusachi, Shinya; Sugimura, Shigeaki; Endo, Haruyuki; Sato, Shigehiro; Ogawa, Akira; Onagawa, Jun

2011-12-01

6 Mcps photon counting was carried out using a detector consisting of a 1.0 mm-thick LSO [Lu 2(SiO 4)O] single-crystal scintillator and an MPPC (multipixel photon counter) module in an X-ray computed tomography (CT) system. The maximum count rate was 6 Mcps (mega counts per second) at a tube voltage of 100 kV and a tube current of 0.91 mA. Next, a photon-counting X-ray CT system consists of an X-ray generator, a turntable, a scan stage, a two-stage controller, the LSO-MPPC detector, a counter card (CC), and a personal computer (PC). Tomography is accomplished by repeated linear scans and rotations of an object, and projection curves of the object are obtained by the linear scan with a scan velocity of 25 mm/s. The pulses of the event signal from the module are counted by the CC in conjunction with the PC. The exposure time for obtaining a tomogram was 600 s at a scan step of 0.5 mm and a rotation step of 1.0°, and photon-counting CT was accomplished using gadolinium-based contrast media.

Photocatalytic degradation of the diazo dye naphthol blue black in water using MWCNT/Gd,N,S-TiO2 nanocomposites under simulated solar light.

PubMed

Mamba, Gcina; Mbianda, Xavier Yangkou; Mishra, Ajay Kumar

2015-07-01

A simple sol-gel method was employed to prepare gadolinium, nitrogen and sulphur tridoped titania decorated on oxidised multiwalled carbon nanotubes (MWCNT/Gd,N,S-TiO2), using titanium (IV) butoxide and thiourea as titanium and nitrogen and sulphur source, respectively. Samples of varying gadolinium loadings (0.2%, 0.6%, 1.0% and 3.0% Gd3+) relative to titania were prepared to investigate the effect of gadolinium loading and the amounts of carbon nanotubes, nitrogen and sulphur were kept constant for all the samples. Furthermore, the prepared nanocomposites were evaluated for the degradation of naphthol blue black (NBB) in water under simulated solar light irradiation. Higher degradation efficiency (95.7%) was recorded for the MWCNT/Gd,N,S-TiO2 (0.6% Gd) nanocomposites. The higher photocatalytic activity is attributed to the combined effect of improved visible light absorption and charge separation due to the synergistic effect of Gd, MWCNTs, N, S and TiO2. Total organic carbon (TOC) analysis revealed a higher degree of complete mineralisation of naphthol blue black (78.0% TOC removal) which minimises the possible formation of toxic degradation by-products such as the aromatic amines. The MWCNT/Gd,N,S-TiO2 (0.6% Gd) was fairly stable and could be re-used for five times, reaching a maximum degradation efficiency of 91.8% after the five cycles. Copyright © 2015. Published by Elsevier B.V.

Synthesis and evaluation of gadolinium complexes based on PAMAM as MRI contrast agents.

PubMed

Yan, Guo-Ping; Hu, Bin; Liu, Mai-Li; Li, Li-Yun

2005-03-01

Diethylenetriaminepentaacetic acid (DTPA) and pyridoxamine (PM) were incorporated into the amine groups on the surface of ammonia-core poly(amidoamine) dendrimers (PAMAM, Generation 2.0-5.0) to obtain dendritic ligands. These dendritic ligands were reacted with gadolinium chloride to yield the corresponding dendritic gadolinium (Gd) complexes. The dendritic ligands and their gadolinium complexes were characterized by(1)HNMR, IR, UV and elemental analysis. Relaxivity studies showed that the dendritic gadolinium complexes possessed higher relaxation effectiveness compared with the clinically used Gd-DTPA. After administration of the dendritic gadolinium complexes (0.09 mmol kg(-1) ) to rats, magnetic resonance imaging of the liver indicated that the dendritic gadolinium complexes containing pyridoxamine groups enhanced the contrast of the MR images of the liver, provided prolonged intravascular duration and produced highly contrasted visualization of blood vessels.

Thermodynamic properties of gadolinium in Ga-Sn and Ga-Zn eutectic based alloys

NASA Astrophysics Data System (ADS)

Maltsev, Dmitry S.; Volkovich, Vladimir A.; Yamshchikov, Leonid F.; Chukin, Andrey V.

2016-09-01

Thermodynamic properties of gadolinium in Ga-Sn and Ga-Zn eutectic based alloys were studied. Temperature dependences of gadolinium activity in the studied alloys were determined at 573-1073 K employing the EMF method. Solubility of gadolinium in the Ga-Sn and Ga-Zn alloys was measured at 462-1073 K using IMCs sedimentation method. Activity coefficients as well as partial and excess thermodynamic functions of gadolinium in the studied alloys were calculated on the basis of the obtained experimental data.

Late Gadolinium Enhancement Amount As an Independent Risk Factor for the Incidence of Adverse Cardiovascular Events in Patients with Stage C or D Heart Failure

PubMed Central

Liu, Tong; Ma, Xiaohai; Liu, Wei; Ling, Shukuan; Zhao, Lei; Xu, Lei; Song, Deli; Liu, Jie; Sun, Zhonghua; Fan, Zhanming; Luo, Taiyang; Kang, Junping; Liu, Xiaohui; Dong, Jianzeng

2016-01-01

Background: Myocardial fibrosis (MF) is a risk factor for poor prognosis in dilated cardiomyopathy (DCM). Late gadolinium enhancement (LGE) of the myocardium on cardiac magnetic resonance (CMR) represents MF. We examined whether the LGE amount increases the incidence of adverse cardiovascular events in patients with stage C or D heart failure (HF). Methods: Eighty-four consecutive patients with stage C or D HF, either ischemic or non-ischemic, were enrolled. Comprehensive clinical and CMR evaluations were performed. All patients were followed up for a composite endpoint of cardiovascular death, heart transplantation, and cardiac resynchronization therapy with defibrillator (CRT-D). Results: LGE was present in 79.7% of the end-stage HF patients. LGE distribution patterns were mid-wall, epi-myocardial, endo-myocardial, and the morphological patterns were patchy, transmural, and diffuse. During the average follow-up of 544 days, 13 (15.5%) patients had endpoint events: 7 patients cardiac death, 2 patients heart transplantation, and 4 patients underwent CRT-D implantation. On univariate analysis, LGE quantification on cardiac magnetic resonance, blood urine nitrogen, QRS duration on electrocardiogram, left ventricular end-diastolic diameter (LVEDD), and left ventricular end-diastolic volume (LVEDV) on CMR had the strongest associations with the composite endpoint events. However, on multivariate analysis for both Model I (after adjusting for age, sex, and body mass index) and Model II (after adjusting for age, sex, BMI, renal function, QRS duration, and atrial fibrillation on electrocardiogram, the etiology of HF, LVEF, CMR-LVEDD, and CMR-LVEDV), LGE amount was a significant risk factor for composite endpoint events (Model I 6SD HR 1.037, 95%CI 1.005–1.071, p = 0.022; Model II 6SD HR 1.045, 95%CI 1.001–1.084, p = 0.022). Conclusion: LGE amount from high-scale threshold on CMR increased the incidence of adverse cardiovascular events for patients in either stage C or D HF. PMID:27840608

Gadolinium diethylenetriaminopentaacetic acid-loaded chitosan microspheres for gadolinium neutron-capture therapy.

PubMed

Saha, Tapan Kumar; Ichikawa, Hideki; Fukumori, Yoshinobu

2006-12-11

In order to provide a suitable device that would contain water-soluble drugs, highly water-soluble gadolinium diethylenetriaminopentaacetic acid-loaded chitosan microspheres (CMS-Gd-DTPA) were prepared by the emulsion method using glutaraldehyde as a cross-linker and Span 80 as a surfactant for gadolinium neutron-capture therapy of cancer. The gadolinium content and the mass median diameter of CMS-Gd-DTPA were estimated. The size and morphology of the CMS-Gd-DTPA were strongly influenced by the initial applied weight ratio of Gd-DTPA:chitosan. FTIR spectra showed that the electrostatic interaction between chitosan and Gd-DTPA accelerated the formation of gadolinium-enriched chitosan microspheres. Sufficient amounts of glutaraldehyde and Span 80 were necessary for producing discrete CMS-Gd-DTPA. The CMS-Gd-DTPA having a mass median diameter 11.7microm and 11.6% of gadolinium could be used in Gd-NCT following intratumoral injection.

Nephrogenic Systemic Fibrosis Manifesting a Decade After Exposure to Gadolinium.

PubMed

Larson, Krista N; Gagnon, Amy L; Darling, Melissa D; Patterson, James W; Cropley, Thomas G

2015-10-01

Nephrogenic systemic fibrosis (NSF) is a fibrosing skin disorder that develops in patients with kidney failure and has been linked to exposure to gadolinium-containing contrast agents. The time between exposure to gadolinium and the initial presentation of NSF is typically weeks to months but has been documented to be as long as 3½ years. We report a case of NSF developing 10 years after exposure to gadolinium. A long-term hemodialysis patient was exposed to gadolinium several times between 1998 and 2004 during magnetic resonance angiography of his abdominal vessels and arteriovenous fistula. In 2014, he was seen at our clinic with new dermal papules and plaques. Biopsy of affected skin showed thickening of collagen, CD34+ spindle cells, and increased mucin in the dermis, supporting the diagnosis of NSF. The clinical history and histopathological features of this case support the diagnosis of NSF 10 years after exposure to gadolinium. Although the use of gadolinium contrast agents in patients with kidney failure has markedly decreased, patients with exposure to gadolinium years to decades previously may manifest the disease.

Structural, optical and magnetic properties of gadolinium sesquioxide nanobars synthesized via thermal decomposition of gadolinium oxalate

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

Manigandan, R.; Giribabu, K.; Suresh, R.

2013-10-15

Graphical abstract: - Highlights: • The cubic Gd{sub 2}O{sub 3} nanobars are synthesized by decomposition of C{sub 6}H{sub 20}Gd{sub 2}O{sub 22}. • The nanoparticles are rectangular bar shape with high porous surface. • The combination of magnetic and optical properties within a single particle. • The Gd{sub 2}O{sub 3} nanobars have tailorable nanostructure, wide bandgap and are paramagnetic. - Abstract: Gadolinium oxide nanobars were obtained by thermal decomposition of gadolinium oxalate, which was synthesized by the chemical precipitation method along with glycerol. The functional group analysis and formation of gadolinium oxide from gadolinium oxalate were characterized by the Fourier transformmore » infrared spectroscopy and thermo gravimetric analyzer. The crystal structure, average crystallite size, and lattice parameter were analyzed by X-ray diffraction technique. Moreover, Raman shifts, elemental composition and morphology of the gadolinium oxide was widely investigated by the laser Raman microscope, X-ray photoelectron spectroscopy, FE-SEM-EDAX and HR-TEM, respectively. Furthermore, the optical properties like band gap, absorbance measurement of the gadolinium oxide were extensively examined. In addition, the paramagnetic property of gadolinium oxide nanobars was explored by the vibrating sample magnetometer.« less

Feasibility and accuracy of dual-layer spectral detector computed tomography for quantification of gadolinium: a phantom study.

PubMed

van Hamersvelt, Robbert W; Willemink, Martin J; de Jong, Pim A; Milles, Julien; Vlassenbroek, Alain; Schilham, Arnold M R; Leiner, Tim

2017-09-01

The aim of this study was to evaluate the feasibility and accuracy of dual-layer spectral detector CT (SDCT) for the quantification of clinically encountered gadolinium concentrations. The cardiac chamber of an anthropomorphic thoracic phantom was equipped with 14 tubular inserts containing different gadolinium concentrations, ranging from 0 to 26.3 mg/mL (0.0, 0.1, 0.2, 0.4, 0.5, 1.0, 2.0, 3.0, 4.0, 5.1, 10.6, 15.7, 20.7 and 26.3 mg/mL). Images were acquired using a novel 64-detector row SDCT system at 120 and 140 kVp. Acquisitions were repeated five times to assess reproducibility. Regions of interest (ROIs) were drawn on three slices per insert. A spectral plot was extracted for every ROI and mean attenuation profiles were fitted to known attenuation profiles of water and pure gadolinium using in-house-developed software to calculate gadolinium concentrations. At both 120 and 140 kVp, excellent correlations between scan repetitions and true and measured gadolinium concentrations were found (R > 0.99, P < 0.001; ICCs > 0.99, CI 0.99-1.00). Relative mean measurement errors stayed below 10% down to 2.0 mg/mL true gadolinium concentration at 120 kVp and below 5% down to 1.0 mg/mL true gadolinium concentration at 140 kVp. SDCT allows for accurate quantification of gadolinium at both 120 and 140 kVp. Lowest measurement errors were found for 140 kVp acquisitions. • Gadolinium quantification may be useful in patients with contraindication to iodine. • Dual-layer spectral detector CT allows for overall accurate quantification of gadolinium. • Interscan variability of gadolinium quantification using SDCT material decomposition is excellent.

The dosimetric impact of gadolinium-based contrast media in GBM brain patient plans for a MRI-Linac

NASA Astrophysics Data System (ADS)

Bilal Ahmad, Syed; Paudel, Moti Raj; Sarfehnia, Arman; Kim, Anthony; Pang, Geordi; Ruschin, Mark; Sahgal, Arjun; Keller, Brian M.

2017-08-01

Dosimetric effects of gadolinium based contrast media (Gadovist) were evaluated for the Elekta MRI linear accelerator using the research version of the Monaco treatment planning system (TPS). In order to represent a gadolinium uptake, the contrast was manually assigned to a phantom as well as to the gross tumour volume (GTV) of 6 glioblastoma multiforme (GBM) patients. A preliminary estimate of the dose enhancement, due to gadolinium, was performed using the phantom irradiated with a single beam. A more complicated assessment was performed for the GBM patients using a 7 field IMRT technique. The material table in Monaco was modified in order to identify the presence of a non-biological material. The dose distribution was modelled using GPUMCD (MC algorithm in Monaco) for an unmodified (or default) material table (DMT) as well as for a modified (or custom) material table (CMT) for both the phantom and patients. Various concentrations ranging between 8 and 157 mg ml-1 were used to represent the gadolinium uptake in the patient’s GTV. It was assumed that the gadolinium concentration remained the same for the entire course of radiation treatment. Results showed that at the tissue-Gadovist interface, inside the phantom, dose scored using the DMT was 7% lower compared to that using the CMT for 157 mg ml-1 concentration of gadolinium. Dosimetric differences in the case of the patient study were measured using the DVH parameters. D 50% was higher by 6% when the DMT was used compared to the CMT for dose modelling for a gadolinium concentration of 157 mg ml-1. This difference decreased gradually with decreasing concentration of gadolinium. It was concluded that dosimetric differences can be quantified in Monaco if the tumour-gadolinium concentration is more than 23 mg ml-1. If the gadolinium concentration is lower than 23 mg ml-1, then a correction for the presence of gadolinium may not be necessary in the TPS.

The dosimetric impact of gadolinium-based contrast media in GBM brain patient plans for a MRI-Linac.

PubMed

Ahmad, Syed Bilal; Paudel, Moti Raj; Sarfehnia, Arman; Kim, Anthony; Pang, Geordi; Ruschin, Mark; Sahgal, Arjun; Keller, Brian M

2017-08-01

Dosimetric effects of gadolinium based contrast media (Gadovist) were evaluated for the Elekta MRI linear accelerator using the research version of the Monaco treatment planning system (TPS). In order to represent a gadolinium uptake, the contrast was manually assigned to a phantom as well as to the gross tumour volume (GTV) of 6 glioblastoma multiforme (GBM) patients. A preliminary estimate of the dose enhancement, due to gadolinium, was performed using the phantom irradiated with a single beam. A more complicated assessment was performed for the GBM patients using a 7 field IMRT technique. The material table in Monaco was modified in order to identify the presence of a non-biological material. The dose distribution was modelled using GPUMCD (MC algorithm in Monaco) for an unmodified (or default) material table (DMT) as well as for a modified (or custom) material table (CMT) for both the phantom and patients. Various concentrations ranging between 8 and 157 mg ml -1 were used to represent the gadolinium uptake in the patient's GTV. It was assumed that the gadolinium concentration remained the same for the entire course of radiation treatment. Results showed that at the tissue-Gadovist interface, inside the phantom, dose scored using the DMT was 7% lower compared to that using the CMT for 157 mg ml -1 concentration of gadolinium. Dosimetric differences in the case of the patient study were measured using the DVH parameters. D 50% was higher by 6% when the DMT was used compared to the CMT for dose modelling for a gadolinium concentration of 157 mg ml -1 . This difference decreased gradually with decreasing concentration of gadolinium. It was concluded that dosimetric differences can be quantified in Monaco if the tumour-gadolinium concentration is more than 23 mg ml -1 . If the gadolinium concentration is lower than 23 mg ml -1 , then a correction for the presence of gadolinium may not be necessary in the TPS.

Pediatric Patients Demonstrate Progressive T1-Weighted Hyperintensity in the Dentate Nucleus following Multiple Doses of Gadolinium-Based Contrast Agent.

PubMed

Roberts, D R; Chatterjee, A R; Yazdani, M; Marebwa, B; Brown, T; Collins, H; Bolles, G; Jenrette, J M; Nietert, P J; Zhu, X

2016-12-01

While there have been recent reports of brain retention of gadolinium following gadolinium-based contrast agent administration in adults, a retrospective series of pediatric patients has not previously been reported, to our knowledge. We investigated the relationship between the number of prior gadolinium-based contrast agent doses and increasing T1 signal in the dentate nucleus on unenhanced T1-weighted MR imaging. We hypothesized that despite differences in pediatric physiology and the smaller gadolinium-based contrast agent doses that pediatric patients are typically administered based on weighted-adjusted dosing, the pediatric brain would also demonstrate dose-dependent increasing T1 signal in the dentate nucleus. We included children with multiple gadolinium-based contrast agent administrations at our institution. A blinded reader placed ROIs within the dentate nucleus and adjacent cerebellar white matter. To eliminate reader bias, we also performed automated ROI delineation of the dentate nucleus, cerebellar white matter, and pons. Dentate-to-cerebellar white matter and dentate-to pons ratios were compared with the number of gadolinium-based contrast agent administrations. During 20 years at our institution, 280 patients received at least 5 gadolinium-based contrast agent doses, with 1 patient receiving 38 doses. Sixteen patients met the inclusion/exclusion criteria for ROI analysis. Blinded reader dentate-to-cerebellar white matter ratios were significantly associated with gadolinium-based contrast agent doses (r s = 0.77, P = .001). The dentate-to-pons ratio and dentate-to-cerebellar white matter ratios based on automated ROI placement were also significantly correlated with gadolinium-based contrast agent doses (t = 4.98, P < .0001 and t = 2.73, P < .02, respectively). In pediatric patients, the number of prior gadolinium-based contrast agent doses is significantly correlated with progressive T1-weighted dentate hyperintensity. Definitive confirmation of gadolinium deposition requires tissue analysis. Any potential clinical sequelae of gadolinium retention in the developing brain are unknown. Given this uncertainty, we suggest taking a cautious stance, including the use, in pediatric patients, of higher stability, macrocyclic agents, which in both human and animal studies have been shown to be associated with lower levels of gadolinium deposition, and detailed documentation of dosing. Most important, a patient should not be deprived of a well-indicated contrasted MR examination. © 2016 by American Journal of Neuroradiology.

Gadolinium-enhanced cardiovascular magnetic resonance: administered dose in relationship to United States Food and Drug Administration (FDA) guidelines.

PubMed

Nacif, Marcelo S; Arai, Andrew E; Lima, Joao A C; Bluemke, David A

2012-02-29

Myocardial late gadolinium enhancement was originally validated using higher than label-recommended doses of gadolinium chelate. The objective of this study was to evaluate available evidence for various gadolinium dosing regimens used for CMR. The relationship of gadolinium dose warnings (due to nephrogenic systemic fibrosis) announced in 2008 to gadolinium dosing regimens was also examined. We conducted a meta-analysis of peer reviewed publications from January, 2004 to December, 2010. Major subject search headings (MeSh) terms from the National Library of Medicine's PubMed were: contrast media, gadolinium, heart, magnetic resonance imaging; searches were limited to human studies with abstracts published in English. Case reports, review articles, editorials, MRA related papers and all reports that did not indicate gadolinium type or weight-based dose were excluded. For all included references, full text was available to determine the total administered gadolinium dose on a per kg basis. Average and median dose values were weighted by the number of subjects in each study. 399 publications were identified in PubMed; 233 studies matched the inclusion criteria, encompassing 19,934 patients with mean age 54.2 ± 11.4 (range 9.3 to 76 years). 34 trials were related to perfusion testing and 199 to myocardial late gadolinium enhancement. In 2004, the weighted-median and weighted-mean contrast dose were 0.15 and 0.16 ± 0.06 mmol/kg, respectively. Median contrast doses for 2005-2010 were: 0.2 mmol/kg for all years, respectively. Mean contrast doses for the years 2005-2010 were: 0.19 ± 0.03, 0.18 ± 0.04, 0.18 ± 0.10, 0.18 ± 0.03, 0.18 ± 0.04 and 0.18 ± 0.04 mmol/kg, respectively (p for trend, NS). Gadopentetate dimeglumine was the most frequent gadolinium type [114 (48.9%) studies]. No change in mean gadolinium dose was present before, versus after the Food and Drug Administration (FDA) black box warning (p > 0.05). Three multi-center dose ranging trials have been published for cardiac MRI applications. CMR studies in the peer-reviewed published literature routinely use higher gadolinium doses than regulatory agencies indicated in the package leaflet. Clinical trials should be supported to determine the appropriate doses of gadolinium for CMR studies.

Pathophysiology of gadolinium-associated systemic fibrosis

PubMed Central

Drel, Viktor; Gorin, Yves

2016-01-01

Systemic fibrosis from gadolinium-based magnetic resonance imaging contrast is a scourge for the afflicted. Although gadolinium-associated systemic fibrosis is a rare condition, the threat of litigation has vastly altered clinical practice. Most theories concerning the etiology of the fibrosis are grounded in case reports rather than experiment. This has led to the widely accepted conjecture that the relative affinity of certain contrast agents for the gadolinium ion inversely correlates with the risk of succumbing to the disease. How gadolinium-containing contrast agents trigger widespread and site-specific systemic fibrosis and how chronicity is maintained are largely unknown. This review highlights experimentally-derived information from our laboratory and others that pertain to our understanding of the pathophysiology of gadolinium-associated systemic fibrosis. PMID:27147669

Production and study of radionuclides at the research institute of atomic reactors (NIIAR)

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

Karelin, E.A.; Gordeev, Y.N.; Filimonov, V.T.

1995-01-01

The main works of the Radionuclide Sources and Preparations Department (ORIP) of the Research Institute of Atomic Reactors (NIIAR) are summarized. The major activity of the Radionuclide Sources and Preparations Department (ORIP) is aimed at production of radioactive preparations of trans-plutonium elements (TPE) and also of lighter elements (from P to Ir), manufacture of ionizing radiation sources thereof, and scientific research to develop new technologies. One of the radionuclides that recently has received major attention is gadolinium-153. Photon sources based on it are used in densimeters for diagnostics of bone deseases. The procedure for separating gadolinium and europium, which ismore » currently used at the Research Institute of Atomic Reactors (NILAR), is based on europium cementation with the use of sodium amalgam. The method, though efficient, did not until recently permit an exhaustive removal of radioactive europium from {sup 153}Gd. The authors have thoroughly studied the separation process in semi-countercurrent mode, using citrate solutions. A special attention was given to the composition of europium complex species.« less

Selective modification of NMR relaxation time in human colorectal carcinoma by using gadolinium-diethylenetriaminepentaacetic acid conjugated with monoclonal antibody 19-9.

PubMed Central

Curtet, C; Tellier, C; Bohy, J; Conti, M L; Saccavini, J C; Thedrez, P; Douillard, J Y; Chatal, J F; Koprowski, H

1986-01-01

Monoclonal antibody 19-9 (mAb 19-9) against human colon adenocarcinoma was conjugated with gadolinium X diethylenetriaminepentaacetic acid (Gd X DTPA) and used as a contrast agent in nuclear magnetic resonance (NMR) in an effort to improve tumor target selectivity in nude mice. The data indicate that Gd X DTPA-mAb 19-9 in solution decreased the T1 relaxation of water protons at 90 MHz in direct proportion to the gadolinium concentration, and this effect was greater than in Gd X DTPA solutions. T1 relaxation time at 90 MHz, measured in tumors removed from nude mice 24 hr after injection of Gd X DTPA-mAb 19-9 (Gd, 20 mumol/kg; 16 DTPA molecules per mAb molecule), was significantly decreased (by 15%) as compared with the control group. Similar results were obtained in tumors from mice injected with Gd X DTPA-mAb 19-9 solutions in which Gd was used at 2, 6, or 10 mumol/kg (16 DTPA molecules per mAb molecule). These doses are lower than those commonly used for Gd X DTPA (10-100 mumol/kg) as contrast agent. Tumor localization by the Gd X DTPA-mAb 19-9 complex containing radioactive Gd (0.3 microCi/microgram of 153Gd) to confirm scintigraphy revealed significant concentrations of the complex (5% of the injected dose per gram of tissue) in the tumor. Scan images recorded in planar scintigraphy at day 5 showed good visualization of tumors. Images PMID:3459174

Magnetic resonance imaging with gadolinium arthrography to assess acetabular cartilage delamination.

PubMed

Zaragoza, Edward; Lattanzio, Pierre-Jean; Beaule, Paul E

2009-01-01

Recent reports have demonstrated magnetic resonance imaging (MRI) as a promising technique in detecting articular cartilage lesions of the hip joint. The purpose of our study was to evaluate the diagnostic performance of MRI with gadolinium arthrography in detecting acetabular cartilage delamination in patients with pre-arthritic hip pain. 46 patients (48 hips) underwent surgical dislocation of the hip. Mean age was 38.8 (range 17-56). There were 26 males and 20 females. All patients had Magnetic Resonance Imaging with gadolinium arthrography (MRA) before undergoing open hip surgery where the acetabular cartilage was inspected. Acetabular cartilage delamination on MRA was seen on sagittal images as a linear intra-articular filling defect of low signal intensity >1mm in thickness on T1 weighted images and surrounded by contrast. On MRA all hips had a labral tear confirmed at surgery. At surgery 30 hips had evidence of acetabular cartilage delamination, 4 hips had ulceration and 14 had no articular cartilage damage. The majority of labral tears and cartilage damage were located in the antero-superior quadrant. The sensitivity and specificity of MRA detection of cartilage delamination confirmed at surgery were 97% and 84%, respectively. The positive and negative predictive values of the MRA finding were 90% and 94%, respectively. The presence of the acetabular cartilage delamination represents an early stage of articular cartilage degeneration. When evaluating a young adult with hip pain, labral tears in association with cartilage delamination should be considered. MRA represents an effective diagnostic tool.

Growth control in colon epithelial cells: gadolinium enhances calcium-mediated growth regulation.

PubMed

Attili, Durga; Jenkins, Brian; Aslam, Muhammad Nadeem; Dame, Michael K; Varani, James

2012-12-01

Gadolinium, a member of the lanthanoid family of transition metals, interacts with calcium-binding sites on proteins and other biological molecules. The overall goal of the present investigation was to determine if gadolinium could enhance calcium-induced epithelial cell growth inhibition in the colon. Gadolinium at concentrations as low as 1-5 μM combined with calcium inhibits proliferation of human colonic epithelial cells more effectively than calcium alone. Gadolinium had no detectable effect on calcium-induced differentiation in the same cells based on change in cell morphology, induction of E-cadherin synthesis, and translocation of E-cadherin from the cytosol to the cell surface. When the colon epithelial cells were treated with gadolinium and then exposed to increased calcium concentrations, movement of extracellular calcium into the cell was suppressed. In contrast, gadolinium treatment had no effect on ionomycin-induced release of stored intracellular calcium into the cytoplasm. Whether these in vitro observations can be translated into an approach for reducing abnormal proliferation in the colonic mucosa (including polyp formation) is not known. These results do, however, provide an explanation for our recent findings that a multi-mineral supplement containing all of the naturally occurring lanthanoid metals including gadolinium are more effective than calcium alone in preventing colon polyp formation in mice on a high-fat diet.

Technical aspects of MRI signal change quantification after gadolinium-based contrast agents' administration.

PubMed

Ramalho, Joana; Ramalho, Miguel; AlObaidy, Mamdoh; Semelka, Richard C

2016-12-01

Over the last 2years several studies have been published regarding gadolinium deposition in brain structures in patients with normal renal function after repeated administrations of gadolinium-based contrast agents (GBCAs). Most of the publications are magnetic resonance imaging (MRI) based retrospective studies, where gadolinium deposition may be indirectly measured by evaluating changes in T1 signal intensity (SI) in brain tissue, particularly in the dentate nucleus (DN) and/or globus pallidi (GP). The direct correlation between T1 signal changes and gadolinium deposition was validated by human pathology studies. However, the variability of the MR equipment and parameters used across different publications, along with the inherent limitations of MRI to assess gadolinium in human tissues should be acknowledged when interpreting those studies. Nevertheless, MRI studies remain essential regarding gadolinium bio-distribution knowledge. The aim of this paper is to overview current knowledge of technical aspects of T1 signal intensity evaluation by MRI and describe confounding factors, with the intention to achieve higher accuracy and maximize reproducibility. Copyright © 2016 Elsevier Inc. All rights reserved.

Growth Control in Colon Epithelial Cells: Gadolinium Enhances Calcium-Mediated Growth Regulation

PubMed Central

Attili, Durga; Jenkins, Brian; Aslam, Muhammad Nadeem; Dame, Michael K.

2013-01-01

Gadolinium, a member of the lanthanoid family of transition metals, interacts with calcium-binding sites on proteins and other biological molecules. The overall goal of the present investigation was to determine if gadolinium could enhance calcium-induced epithelial cell growth inhibition in the colon. Gadolinium at concentrations as low as 1–5 µM combined with calcium inhibits proliferation of human colonic epithelial cells more effectively than calcium alone. Gadolinium had no detectable effect on calcium-induced differentiation in the same cells based on change in cell morphology, induction of E-cadherin synthesis, and translocation of E-cadherin from the cytosol to the cell surface. When the colon epithelial cells were treated with gadolinium and then exposed to increased calcium concentrations, movement of extracellular calcium into the cell was suppressed. In contrast, gadolinium treatment had no effect on ionomycin-induced release of stored intracellular calcium into the cytoplasm. Whether these in vitro observations can be translated into an approach for reducing abnormal proliferation in the colonic mucosa (including polyp formation) is not known. These results do, however, provide an explanation for our recent findings that a multi-mineral supplement containing all of the naturally occurring lanthanoid metals including gadolinium are more effective than calcium alone in preventing colon polyp formation in mice on a high-fat diet. PMID:23008064

Gadolinium Deposition in Human Brain Tissues after Contrast-enhanced MR Imaging in Adult Patients without Intracranial Abnormalities.

PubMed

McDonald, Robert J; McDonald, Jennifer S; Kallmes, David F; Jentoft, Mark E; Paolini, Michael A; Murray, David L; Williamson, Eric E; Eckel, Laurence J

2017-11-01

Purpose To determine whether gadolinium deposits in neural tissues of patients with intracranial abnormalities following intravenous gadolinium-based contrast agent (GBCA) exposure might be related to blood-brain barrier integrity by studying adult patients with normal brain pathologic characteristics. Materials and Methods After obtaining antemortem consent and institutional review board approval, the authors compared postmortem neuronal tissue samples from five patients who had undergone four to 18 gadolinium-enhanced magnetic resonance (MR) examinations between 2005 and 2014 (contrast group) with samples from 10 gadolinium-naive patients who had undergone at least one MR examination during their lifetime (control group). All patients in the contrast group had received gadodiamide. Neuronal tissues from the dentate nuclei, pons, globus pallidus, and thalamus were harvested and analyzed with inductively coupled plasma mass spectrometry (ICP-MS), transmission electron microscopy with energy-dispersive x-ray spectroscopy, and light microscopy to quantify, localize, and assess the effects of gadolinium deposition. Results Tissues from the four neuroanatomic regions of gadodiamide-exposed patients contained 0.1-19.4 μg of gadolinium per gram of tissue in a statistically significant dose-dependent relationship (globus pallidus: ρ = 0.90, P = .04). In contradistinction, patients in the control group had undetectable levels of gadolinium with ICP-MS. All patients had normal brain pathologic characteristics at autopsy. Three patients in the contrast group had borderline renal function (estimated glomerular filtration rate <45 mL/min/1.73 m 2 ) and hepatobiliary dysfunction at MR examination. Gadolinium deposition in the contrast group was localized to the capillary endothelium and neuronal interstitium and, in two cases, within the nucleus of the cell. Conclusion Gadolinium deposition in neural tissues after GBCA administration occurs in the absence of intracranial abnormalities that might affect the permeability of the blood-brain barrier. These findings challenge current understanding of the biodistribution of these contrast agents and their safety. © RSNA, 2017.

In vitro comparison of intracranial stent visibility using various concentrations of gadolinium contrast agent under 1.5 T and 3 T MR angiography.

PubMed

Chiang, Chen-Hua; Tseng, Ying-Chi; Chen, Ai-Chi; Huang, Yen-Lin; Chen, David Yen-Ting; Chen, Chi-Jen; Lin, Yen-Kuang; Hsu, Hui-Ling

2017-04-01

MR angiography (MRA) is an increasingly used evaluation method following intracranial stenting. However, the various artifacts created by the stent limit this technique. The purpose of this study was to investigate the effects of various concentrations of gadolinium contrast agent on the visibility and signal characteristics of two stents using the a contrast enhanced MRA technique. Two intracranial stents (Enterprise and Helistent) were placed in polyvinyl chloride tubes as vascular phantoms. They were filled with six different doses of gadolinium contrast agent (1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 mmol/L dimeglumine gadopentetate, respectively) and imaged using 3 T and 1.5 T MR systems. Relative in-stent signal (RIS) was calculated and artificial luminal narrowing (ALN) was obtained using pixel by pixel analysis. The Enterprise stent, performed in both 1.5 T and 3 T MR systems, showed mean RIS values much less than those for the Helistent for all different doses of gadolinium solution. Increased gadolinium concentration resulted in a gradual reduction in RIS values in the Enterprise group. Also, ALN in the Enterprise group showed no or little change with various gadolinium doses. The Enterprise stent demonstrated good luminal visibility regardless of gadolinium concentration. The relative in-stent signals were more predictable in the Enterprise stent with various doses of gadolinium. Therefore, the Enterprise stent has been shown to provide better in-stent visibility compared with the Helistent using various gadolinium doses. 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/.

Gadolinium Use in Spine Pain Management Procedures for Patients with Contrast Allergies: Results in 527 Procedures

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

Safriel, Yair; Ang, Roberto; Ali, Muhammed

2008-03-15

Introduction. To review the safety and efficacy of gadolinium in spine pain management procedures in patients at high risk for a contrast reaction and who are not suitable candidates for the use of standard non-ionic contrast. Methods. We reviewed records over a 61-month period of all image-guided spinal pain management procedures where patients had allergies making them unsuitable candidates for standard non-ionic contrast and where gadolinium was used to confirm needle tip placement prior to injection of medication. Results. Three hundred and four outpatients underwent 527 procedures. A spinal needle was used in all but 41 procedures. Gadolinium was visualizedmore » using portable C-arm fluoroscopy in vivo allowing for confirmation of needle tip location. The gadolinium dose ranged from 0.2 to 10 ml per level. The highest dose received by one patient was 15.83 ml intradiscally during a three-level discogram. Three hundred and one patients were discharged without complication or known delayed complications. One patient had documented intrathecal injection but without sequelae and 2 patients who underwent cervical procedures experienced seizures requiring admission to the intensive care unit. Both the latter patients were discharged without any further complications. Conclusion. Based on our experience we recommend using gadolinium judiciously for needle tip confirmation. We feel more confident using gadolinium in the lumbar spine and in cervical nerve blocks. Gadolinium should probably not be used as an injectate volume expander. The indications for gadolinium use in cervical needle-guided spine procedures are less clear and use of a blunt-tipped needle should be considered.« less

Identification and characterization of gadolinium(III) complexes in biological tissue extracts.

PubMed

Kahakachchi, Chethaka L; Moore, Dennis A

2010-07-01

The gadolinium species present in a rat kidney following intravenous administration of a gadolinium-based magnetic resonance contrast agent (Optimark™, Gadoversetamide injection) to a rat was examined in the present study. The major gadolinium species in the supernatant of the rat kidney tissue extracts was determined by reversed-phase liquid chromatography with online inductively coupled plasma optical emission spectrometry (HPLC-ICP-OES). The identity of the compound was established by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) detection. The principal gadolinium(III) complex in a rat kidney tissue extract was identified as Gd-DTPA-BMEA 24 Hrs and 7 days after a single intravenous injection of Optimark™ (gadoversetamide; Gd-DTPA-BMEA) at a dose of 5 mmol Gd/kg body weight. The study demonstrated for the first time the feasibility of the use of two complementary techniques, HPLC-ICP-OES and HPLC-ESI-MS to study the in vivo behavior of gadolinium-based magnetic resonance contrast media.

Proton Relaxivity and Magnetic Hyperthermia Evaluation of Gadolinium Doped Nickel Ferrite Nanoparticles as Potential Theranostic Agents.

PubMed

Yadavalli, Tejabhiram; Raja, Paradeep; Ramaswamy, Shivaraman; Chandrasekharan, Gopalakrishnan; Chennakesavulu, Ramasamy

2017-02-01

This paper outlines the preparation of gadolinium doped nickel ferrite nanoparticles as potential magnetic carriers and longitudinal magnetic resonance imaging contrast agents using hydrothermal method with gadolinium concentration varying from 10% to 40%. A concise effect on the crystal structure was observed at 10% and 20% gadolinium doping, while gadolinium oxide was observed to leach at concentrations exceeding 20%. Further, gadolinium doped nickel ferrites were analyzed for their morphological, magnetic, proton relaxation and magnetic hyperthermia heating properties to understand their potential role as magnetic carrier agents. Low temperature and room temperature magnetic studies conducted on the samples showed comparatively high magnetic saturation with low remanent magnetization. Further, relaxometry studies revealed a high relaxation rate of 6.63 s−1 at a concentration of 0.1 mg/mL. Magnetic hyperthermia studies of the samples at a concentration of 1 mg/mL, assessed that the samples attained a temperature of 68 °C in 240 seconds.

Gadolinium-Based Contrast Agents for MR Cancer Imaging

PubMed Central

Zhou, Zhuxian; Lu, Zheng-Rong

2013-01-01

Magnetic resonance imaging (MRI) is a clinical imaging modality effective for anatomical and functional imaging of diseased soft tissues, including solid tumors. MRI contrast agents have been routinely used for detecting tumor at an early stage. Gadolinium based contrast agents are the most commonly used contrast agents in clinical MRI. There have been significant efforts to design and develop novel Gd(III) contrast agents with high relaxivity, low toxicity and specific tumor binding. The relaxivity of the Gd(III) contrast agents can be increased by proper chemical modification. The toxicity of Gd(III) contrast agents can be reduced by increasing the agents’ thermodynamic and kinetic stability, as well as optimizing their pharmacokinetic properties. The increasing knowledge in the field of cancer genomics and biology provides an opportunity for designing tumor-specific contrast agents. Various new Gd(III) chelates have been designed and evaluated in animal models for more effective cancer MRI. This review outlines the design and development, physicochemical properties, and in vivo properties of several classes of Gd(III)-based MR contrast agents for tumor imaging. PMID:23047730

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

Ogden, K; O’Dwyer, R; Bradford, T

Purpose: To reduce differences in features calculated from MRI brain scans acquired at different field strengths with or without Gadolinium contrast. Methods: Brain scans were processed for 111 epilepsy patients to extract hippocampus and thalamus features. Scans were acquired on 1.5 T scanners with Gadolinium contrast (group A), 1.5T scanners without Gd (group B), and 3.0 T scanners without Gd (group C). A total of 72 features were extracted. Features were extracted from original scans and from scans where the image pixel values were rescaled to the mean of the hippocampi and thalami values. For each data set, cluster analysismore » was performed on the raw feature set and for feature sets with normalization (conversion to Z scores). Two methods of normalization were used: The first was over all values of a given feature, and the second by normalizing within the patient group membership. The clustering software was configured to produce 3 clusters. Group fractions in each cluster were calculated. Results: For features calculated from both the non-rescaled and rescaled data, cluster membership was identical for both the non-normalized and normalized data sets. Cluster 1 was comprised entirely of Group A data, Cluster 2 contained data from all three groups, and Cluster 3 contained data from only groups 1 and 2. For the categorically normalized data sets there was a more uniform distribution of group data in the three Clusters. A less pronounced effect was seen in the rescaled image data features. Conclusion: Image Rescaling and feature renormalization can have a significant effect on the results of clustering analysis. These effects are also likely to influence the results of supervised machine learning algorithms. It may be possible to partly remove the influence of scanner field strength and the presence of Gadolinium based contrast in feature extraction for radiomics applications.« less

The Utility of Cardiac Magnetic Resonance Imaging in the Diagnosis of Cardiac Sarcoidosis.

PubMed

Stanton, Kelly M; Ganigara, Madhusudan; Corte, Peter; Celermajer, David S; McGuire, Mark A; Torzillo, Paul J; Corte, Tamera J; Puranik, Rajesh

2017-11-01

Autopsy reports suggest that cardiac sarcoidosis occurs in 20 to 25% of patients with pulmonary sarcoidosis, yet the clinical ante-mortem diagnosis is made in only 5% of cases. Current diagnostic algorithms are complex and lack sensitivity. Cardiac Magnetic Resonance imaging (CMR) provides an opportunity to detect myocardial involvement in sarcoidosis. The aim of this study is to determine the prevalence and clinical significance of late gadolinium enhancement (LGE) on CMR in patients with sarcoidosis. Consecutive patients with biopsy-proven sarcoidosis undergoing CMR were retrospectively evaluated for cardiac sarcoidosis. Medical records were correlated with CMR. Forty-six patients were evaluated. Late gadolinium enhancement was present in 22%, indicating myocardial involvement, and 70% had corresponding hyper-intense T2 signal indicating active inflammation. Late gadolinium enhancement was 18%+/-9.7% of overall left ventricular (LV) mass and most commonly located in the basal to mid septum. There was no association between LGE and cardiovascular symptoms or pulmonary stage. Eighty per cent of patients with LGE did not fulfill conventional diagnostic criteria for cardiac sarcoidosis. However, LGE was associated with clinically significant arrhythmia (p<0.01) and a lower LVEF (p=0.04). Using CMR, we identified a higher prevalence of cardiac sarcoidosis than previously reported clinical studies, a prevalence which is more consistent with autopsy data. The presence of LGE was highly correlated with clinically significant arrhythmias and lower LVEF. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). All rights reserved.

High specific heat superconducting composite

DOEpatents

Steyert, Jr., William A.

1979-01-01

A composite superconductor formed from a high specific heat ceramic such as gadolinium oxide or gadolinium-aluminum oxide and a conventional metal conductor such as copper or aluminum which are insolubly mixed together to provide adiabatic stability in a superconducting mode of operation. The addition of a few percent of insoluble gadolinium-aluminum oxide powder or gadolinium oxide powder to copper, increases the measured specific heat of the composite by one to two orders of magnitude below the 5.degree. K. level while maintaining the high thermal and electrical conductivity of the conventional metal conductor.

Gadolinium-based magnetic resonance imaging contrast agents in interventional radiology.

PubMed

Atar, Eli

2004-07-01

Gadolinium-based agents are widely used in magnetic resonance imaging as contrast agents. These agents are radio-opaque enough for diagnostic imaging of the vascular tree by using digitally subtracted images as well as for imaging of the biliary system and the urinary tract. The recommended doses for gadolinium do not impair renal function or cause adverse reactions in patients with iodine sensitivity; thus patients with such conditions can safely undergo diagnostic angiography, either by MRI angiography or by catheterization using gadolinium as contrast agent, for diagnostic and therapeutic purposes.

Rare-Earth Ion-Host Lattice Interactions: 15. Analysis of the Spectra of Nd3+ in Gd3Sc2Ga3O12.

DTIC Science & Technology

1984-05-01

Luminescence of Cr3+ Ions in Gadolinium Gallium and Gadolinium Scandium Gallium Garnet CT’stals, Soy. J. Quant. Electron. 12 (1982), 1124. 6M. Dutoit, J. C...Shcherbakov, Absolute Quantum Efficiency of the Luminescence of Cr3+ Ions in Gadolinium Gallium and Gadolinium Scandium Gallium Garnet Crystals, Soy. J...HDL Project: 324332 19. KEY WORDS (Continue on reverse side it necessary end Identify by block number) Rare earth Mixed garnet Spectra Laser Judd-Ofelt

Theoretical study of structure and stability of small gadolinium carboxylate complexes in liquid scintillator solvents.

PubMed

Huang, Pin-Wen

2014-09-01

The structural properties of three small gadolinium carboxylate complexes in three liquid scintillator solvents (pseudocumene, linear alkylbenzene, and phenyl xylylethane) were theoretically investigated using density functional theory (B3LYP/LC-RECP) and polarizable continuum model (PCM). The average interaction energy between gadolinium atom and carboxylate ligand (E(int)) and the energy difference of the highest singly occupied molecular orbital and lowest unoccupied molecular orbital (Δ(SL)) were calculated to evaluate and compare the relative stability of these complexes in solvents. The calculation results show that the larger (with a longer alkyl chain) gadolinium carboxylate complex has greater stability than the smaller one, while these gadolinium carboxylates in linear alkylbenzene were found to have greater stability than those in the other two solvents.

The Effect of Pressure and Temperature on Separation of Free Gadolinium(III) From Gd-DTPA Complex by Nanofiltration-Complexation Method

NASA Astrophysics Data System (ADS)

Rahayu, Iman; Anggraeni, Anni; Ukun, MSS; Bahti, Husein H.

2017-05-01

Nowdays, the utilization of rare earth elements has been carried out widely in industry and medicine, one of them is gadolinium in Gd-DTPA complex is used as a contrast agent in a magnetic resonance imaging (MRI) diagnostic to increase the visual contrast between normal tissue and diseased. Although the stability of a given complex may be high enough, the complexation step couldnot have been completed, so there is possible to gadolinium(III) in the complex compound. Therefore, the function of that compounds should be dangerous because of the toxicity of gadolinium(III) in human body. So, it is necessarry to separate free gadolinium(III) from Gd-DTPA complex by nanofiltration-complexation. The method of this study is complexing of Gd2O3 with DTPA ligand by reflux and separation of Gd-DTPA complex from gadolinium(III) with a nanofiltration membrane on the variation of pressures(2, 3, 4, 5, 6 bars) and temperature (25, 30, 35, 40 °C) and determined the flux and rejection. The results of this study are the higher of pressures and temperatures, permeation flux are increasing and ion rejections are decreasing and gave the free gadolinium(III) rejection until 86.26%.

Helium defectoscopy of cerium gadolinium ceramics Ce0.8Gd0.2O1.9 with a submicrocrystalline structure in the impurity disorder region

NASA Astrophysics Data System (ADS)

Koromyslov, A. V.; Zhiganov, A. N.; Kovalenko, M. A.; Kupryazhkin, A. Ya.

2013-12-01

The concentration of impurity anion vacancies formed upon the dissociation of gadolinium-vacancy complexes has been determined using helium defectoscopy of the cerium gadolinium ceramics Ce0.8Gd0.2O1.9 with a submicrocrystalline structure in the temperature range T = 740-1123 K and at saturation pressures ranging from 0.05 to 15 MPa. It has been found that the energy of dissociation of gadoliniumvacancy complexes is E {eff/ D }= 0.26 ± 0.06 eV, and the energy of dissolution of helium in anion vacancies in the impurity disorder region is E P = -0.31 ± 0.09 eV. The proposed mechanism of dissolution has been confirmed by the investigation of the electrical conductivity of the cerium gadolinium ceramics, as well as by the high-speed molecular dynamics simulation of the dissociation of gadolinium-vacancy complexes. It has been assumed that a decrease in the effective dissolution energy in comparison with the results of the previously performed low-temperature investigations is caused by the mutual repulsion of vacancies formed upon the dissociation of gadolinium-vacancy complexes in highly concentrated solutions of gadolinium in CeO2 with increasing temperature.

Critical Questions Regarding Gadolinium Deposition in the Brain and Body After Injections of the Gadolinium-Based Contrast Agents, Safety, and Clinical Recommendations in Consideration of the EMA's Pharmacovigilance and Risk Assessment Committee Recommendation for Suspension of the Marketing Authorizations for 4 Linear Agents.

PubMed

Runge, Val M

2017-06-01

For magnetic resonance, the established class of intravenous contrast media is the gadolinium-based contrast agents. In the 3 decades since initial approval, these have proven in general to be very safe for human administration. However, in 2006, a devastating late adverse reaction to administration of the less stable gadolinium-based contrast agents was identified, nephrogenic systemic fibrosis. The result of actions taken by the European Medicines Agency and the US Food and Drug Administration, stratifying the agents by risk and contraindicating specific agents in severe renal dysfunction, has led to no new cases being identified in North America or Europe. Subsequently, in 2014, long-term deposition in the brain of gadolinium was first shown, after administration of 2 nonionic linear chelates, gadodiamide, and gadopentetate dimeglumine. This has led to an intense focus on the question of in vivo distribution, possible dechelation, and subsequent deposition of gadolinium, together with substantial clarification of the phenomenon as well as stratification of the agents on this basis. This review focuses on 8 critical questions regarding gadolinium deposition in the brain and body, with the answers and discussion therein important for future regulatory decisions and clinical practice. It is now clear that dechelation of gadolinium occurs in vivo with the linear agents and is responsible for this phenomenon, with key experts in the field recommending, except where there is no suitable alternative, a shift in clinical practice from the linear to macrocyclic agents. In addition, on March 10, 2017, the Pharmacovigilance and Risk Assessment Committee of the European Medicines Agency recommended suspension of the marketing authorization for 4 linear gadolinium contrast agents-specifically Omniscan, Optimark, Magnevist, and MultiHance (gadodiamide, gadoversetamide, gadopentetate dimeglumine, and gadobenate dimeglumine)-for intravenous injection. Cited in the report was convincing evidence of gadolinium deposition in the brain months after injection of these linear agents. Primovist/Eovist (gadoxetic acid disodium) will remain available, being used at a lower dose for liver imaging, because it meets an important diagnostic need. In addition, a formulation of Magnevist for intra-articular injection will remain available because of its very low gadolinium concentration.

The Effect of gadolinium on the ESR response of alanine and ammonium tartrate exposed to thermal neutrons.

PubMed

Marrale, Maurizio; Brai, Maria; Gennaro, Gaetano; Bartolotta, Antonio; D'Oca, Maria Cristina

2008-02-01

Many efforts have been made to develop neutron capture therapy (NCT) for cancer treatment. Among the challenges in using NCT is the characterization of the features of the mixed radiation field and of its components. In this study, we examined the enhancement of the ESR response of pellets of alanine and ammonium tartrate with gadolinium oxide exposed to a thermal neutron beam. In particular, the ESR response of these dosimeters as a function of the gadolinium content inside the dosimeter was analyzed. We found that the addition of gadolinium improves the sensitivity of both alanine and ammonium tartrate. However, the use of gadolinium reduces or abolishes tissue equivalence because of its high atomic number (Z(Gd) = 64). Therefore, it is necessary to find the optimum compromise between the sensitivity to thermal neutrons and the reduction of tissue equivalence. Our analysis showed that a low concentration of gadolinium oxide (of the order of 5% of the total mass of the dosimeter) can enhance the thermal neutron sensitivity more than 13 times with an insignificant reduction of tissue equivalence.

Deep learning enables reduced gadolinium dose for contrast-enhanced brain MRI.

PubMed

Gong, Enhao; Pauly, John M; Wintermark, Max; Zaharchuk, Greg

2018-02-13

There are concerns over gadolinium deposition from gadolinium-based contrast agents (GBCA) administration. To reduce gadolinium dose in contrast-enhanced brain MRI using a deep learning method. Retrospective, crossover. Sixty patients receiving clinically indicated contrast-enhanced brain MRI. 3D T 1 -weighted inversion-recovery prepped fast-spoiled-gradient-echo (IR-FSPGR) imaging was acquired at both 1.5T and 3T. In 60 brain MRI exams, the IR-FSPGR sequence was obtained under three conditions: precontrast, postcontrast images with 10% low-dose (0.01mmol/kg) and 100% full-dose (0.1 mmol/kg) of gadobenate dimeglumine. We trained a deep learning model using the first 10 cases (with mixed indications) to approximate full-dose images from the precontrast and low-dose images. Synthesized full-dose images were created using the trained model in two test sets: 20 patients with mixed indications and 30 patients with glioma. For both test sets, low-dose, true full-dose, and the synthesized full-dose postcontrast image sets were compared quantitatively using peak-signal-to-noise-ratios (PSNR) and structural-similarity-index (SSIM). For the test set comprised of 20 patients with mixed indications, two neuroradiologists scored blindly and independently for the three postcontrast image sets, evaluating image quality, motion-artifact suppression, and contrast enhancement compared with precontrast images. Results were assessed using paired t-tests and noninferiority tests. The proposed deep learning method yielded significant (n = 50, P < 0.001) improvements over the low-dose images (>5 dB PSNR gains and >11.0% SSIM). Ratings on image quality (n = 20, P = 0.003) and contrast enhancement (n = 20, P < 0.001) were significantly increased. Compared to true full-dose images, the synthesized full-dose images have a slight but not significant reduction in image quality (n = 20, P = 0.083) and contrast enhancement (n = 20, P = 0.068). Slightly better (n = 20, P = 0.039) motion-artifact suppression was noted in the synthesized images. The noninferiority test rejects the inferiority of the synthesized to true full-dose images for image quality (95% CI: -14-9%), artifacts suppression (95% CI: -5-20%), and contrast enhancement (95% CI: -13-6%). With the proposed deep learning method, gadolinium dose can be reduced 10-fold while preserving contrast information and avoiding significant image quality degradation. 3 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2018. © 2018 International Society for Magnetic Resonance in Medicine.

Speciation and isotope dilution analysis of gadolinium-based contrast agents in wastewater.

PubMed

Telgmann, Lena; Wehe, Christoph A; Birka, Marvin; Künnemeyer, Jens; Nowak, Sascha; Sperling, Michael; Karst, Uwe

2012-11-06

The fate of Gadolinium (Gd)-based contrast agents for magnetic resonance imaging (MRI) during sewage treatment was investigated. The total concentration of Gd in influent and effluent 2 and 24 h composite samples was determined by means of isotope dilution analysis. The balancing of Gd input and output of a sewage plant over seven days indicated that approximately 10% of the Gd is removed during treatment. Batch experiments simulating the aeration tank of a sewage treatment plant confirmed the Gd complex removal during activated sludge treatment. For speciation analysis of the Gd complexes in wastewater samples, high performance liquid chromatography (HPLC) was hyphenated to inductively coupled plasma sector field mass spectrometry (ICP-SFMS). Separation of the five predominantly used contrast agents was carried out on a new hydrophilic interaction liquid chromatography stationary phase in less than 15 min. A limit of detection (LOD) of 0.13 μg/L and a limit of quantification of 0.43 μg/L could be achieved for the Gd chelates without having to apply enrichment techniques. Speciation analysis of the 24 h composite samples revealed that 80% of the Gd complexes are present as Gd-BT-DO3A in the sampled treatment plant. The day-of-week dependent variation of the complex load followed the variation of the total Gd load, indicating a similar behavior. The analysis of sewage sludge did not prove the presence of anthropogenic Gd. However, in the effluent of the chamber filter press, which was used for sludge dewatering, two of the contrast agents and three other unknown Gd species were observed. This indicates that species transformation took place during anaerobic sludge treatment.

Retention of Gadolinium-Based Contrast Agents in Multiple Sclerosis: Retrospective Analysis of an 18-Year Longitudinal Study.

PubMed

Forslin, Y; Shams, S; Hashim, F; Aspelin, P; Bergendal, G; Martola, J; Fredrikson, S; Kristoffersen-Wiberg, M; Granberg, T

2017-07-01

Gadolinium-based contrast agents have been associated with lasting high T1-weighted signal intensity in the dentate nucleus and globus pallidus, with histopathologically confirmed gadolinium retention. We aimed to longitudinally investigate the relationship of multiple gadolinium-based contrast agent administrations to the Signal Intensity Index in the dentate nucleus and globus pallidus and any associations with cognitive function in multiple sclerosis. The Signal Intensity Index in the dentate nucleus and globus pallidus was retrospectively evaluated on T1-weighted MR imaging in an 18-year longitudinal cohort study of 23 patients with MS receiving multiple gadolinium-based contrast agent administrations and 23 healthy age- and sex-matched controls. Participants also underwent comprehensive neuropsychological testing. Patients with MS had a higher Signal Intensity Index in the dentate nucleus ( P < .001), but not in the globus pallidus ( P = .19), compared with non-gadolinium-based contrast agent-exposed healthy controls by an unpaired t test. Increasing numbers of gadolinium-based contrast agent administrations were associated with an increased Signal Intensity Index in the dentate nucleus (β = 0.45, P < .001) and globus pallidus (β = 0.60, P < .001). This association remained stable with corrections for the age, disease duration, and physical disability for both the dentate nucleus (β = 0.43, P = .001) and globus pallidus (β = 0.58, P < .001). An increased Signal Intensity Index in the dentate nucleus among patients with MS was associated with lower verbal fluency scores, which remained significant after correction for several aspects of disease severity (β = -0.40 P = .013). Our data corroborate previous reports of lasting gadolinium retention in brain tissues. An increased Signal Intensity Index in the dentate nucleus and globus pallidus was associated with lower verbal fluency, which does not prove causality but encourages further studies on cognition and gadolinium-based contrast agent administration. © 2017 by American Journal of Neuroradiology.

Distribution and chemical forms of gadolinium in the brain: a review.

PubMed

Kanda, Tomonori; Nakai, Yudai; Hagiwara, Akifumi; Oba, Hiroshi; Toyoda, Keiko; Furui, Shigeru

2017-11-01

In the 3 years since residual gadolinium-based contrast agent (GBCA) in the brain was first reported, much has been learned about its accumulation, including the pathway of GBCA entry into the brain, the brain distribution of GBCA and its excretion. Here we review recent progress in understanding the routes of gadolinium deposition in brain structures.

Gadolinium Distribution in Cerebrospinal Fluid after Administration of a Gadolinium-based MR Contrast Agent in Humans.

PubMed

Berger, Florian; Kubik-Huch, Rahel A; Niemann, Tilo; Schmid, Hans Ruedi; Poetzsch, Michael; Froehlich, Johannes M; Beer, Jürg H; Thali, Michael J; Kraemer, Thomas

2018-05-08

Purpose To evaluate whether gadolinium penetrates human cerebrospinal fluid (CSF) after MR imaging (MRI) with a gadolinium-based contrast agent (GBCA). Materials and Methods For this retrospective study, the authors analyzed 60 CSF samples from 57 patients (median age, 50 years; range, 3-92 years) who underwent one contrast material-enhanced MRI examination with gadoterate meglumine within 60 days of CSF extraction between January and December 2016. CSF samples from patients who underwent MRI without contrast material administration (n = 22) or those who underwent contrast-enhanced MRI at least 1 year before extraction (n = 2) were analyzed and used as control samples. CSF measurements were performed with inductively coupled plasma mass spectrometry by monitoring the gadolinium 158 isotope. Statistical analyses were performed by using a preliminary Kruskal-Wallis test. Results Higher CSF gadolinium concentrations were detected within the first 8 hours after GBCA administration (mean concentration, 1152 ng/mL ± 734.6). Concentrations were lower between 8 and 48 hours (872 ng/mL ± 586). After 48 hours, gadolinium was almost completely cleared from CSF (121 ng/mL ± 296.3). All but two samples from the 24 control patients (median age, 60.5 years; range, 19-79 years) were negative for the presence of gadolinium. Those samples were from patients who had undergone GBCA-enhanced MRI examination more than a year before CSF extraction (0.1 and 0.2 ng/mL after 1 and 3 years, respectively). The concentrations in patients with chronic renal insufficiency (n = 3), cerebral toxoplasmosis (n = 1), and liver cirrhosis (n = 1) were higher than the mean concentrations. Conclusion Gadoterate meglumine can be detected in human CSF after intravenous administration. © RSNA, 2018.

Gadolinium-labeled dendronized gold nanoparticles as new targeted MRI contrast agent

NASA Astrophysics Data System (ADS)

Pan, Hongmu; Daniel, Marie-Christine

2010-04-01

Early diagnosis is critical for positive outcome of cancer treatments. In many cases, lives would be saved if the tumor could be detected at a very early stage. Nanoparticles have the property of passively targeting tumor sites due to their enhanced permeation and retention (EPR) effect. Thus they can play a critical role in improving the ability to find cancer in its earliest and most treatable stages. Furthermore magnetic resonance imaging is one of the most precise techniques for cancer screening since it can show 3D images of the tumors. For a better enhancement of the sensitivity of this method, MRI contrast agent (DOTA)Gd was attached to poly(propylene imine) dendrons of third generation and the obtained dendrons were used for modification of gold nanoparticles.

Controlling the COD removal of an A-stage pilot study with instrumentation and automatic process control.

PubMed

Miller, Mark W; Elliott, Matt; DeArmond, Jon; Kinyua, Maureen; Wett, Bernhard; Murthy, Sudhir; Bott, Charles B

2017-06-01

The pursuit of fully autotrophic nitrogen removal via the anaerobic ammonium oxidation (anammox) pathway has led to an increased interest in carbon removal technologies, particularly the A-stage of the adsorption/bio-oxidation (A/B) process. The high-rate operation of the A-stage and lack of automatic process control often results in wide variations of chemical oxygen demand (COD) removal that can ultimately impact nitrogen removal in the downstream B-stage process. This study evaluated the use dissolved oxygen (DO) and mixed liquor suspended solids (MLSS) based automatic control strategies through the use of in situ on-line sensors in the A-stage of an A/B pilot study. The objective of using these control strategies was to reduce the variability of COD removal by the A-stage and thus the variability of the effluent C/N. The use of cascade DO control in the A-stage did not impact COD removal at the conditions tested in this study, likely because the bulk DO concentration (>0.5 mg/L) was maintained above the half saturation coefficient of heterotrophic organisms for DO. MLSS-based solids retention time (SRT) control, where MLSS was used as a surrogate for SRT, did not significantly reduce the effluent C/N variability but it was able to reduce COD removal variation in the A-stage by 90%.

Alkali metal and alkali earth metal gadolinium halide scintillators

DOEpatents

Bourret-Courchesne, Edith; Derenzo, Stephen E.; Parms, Shameka; Porter-Chapman, Yetta D.; Wiggins, Latoria K.

2016-08-02

The present invention provides for a composition comprising an inorganic scintillator comprising a gadolinium halide, optionally cerium-doped, having the formula A.sub.nGdX.sub.m:Ce; wherein A is nothing, an alkali metal, such as Li or Na, or an alkali earth metal, such as Ba; X is F, Br, Cl, or I; n is an integer from 1 to 2; m is an integer from 4 to 7; and the molar percent of cerium is 0% to 100%. The gadolinium halides or alkali earth metal gadolinium halides are scintillators and produce a bright luminescence upon irradiation by a suitable radiation.

Compensated gadolinium-loaded plastic scintillators for thermal neutron detection (and counting)

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

Dumazert, Jonathan; Coulon, Romain; Bertrand, Guillaume H. V.

2015-07-01

Plastic scintillator loading with gadolinium-rich organometallic complexes shows a high potential for the deployment of efficient and cost-effective neutron detectors. Due to the low-energy photon and electron signature of thermal neutron capture by gadolinium-155 and gadolinium-157, alternative treatment to Pulse Shape Discrimination has to be proposed in order to display a trustable count rate. This paper discloses the principle of a compensation method applied to a two-scintillator system: a detection scintillator interacts with photon radiation and is loaded with gadolinium organometallic compound to become a thermal neutron absorber, while a non-gadolinium loaded compensation scintillator solely interacts with the photon partmore » of the incident radiation. Posterior to the nonlinear smoothing of the counting signals, a hypothesis test determines whether the resulting count rate after photon response compensation falls into statistical fluctuations or provides a robust image of a neutron activity. A laboratory prototype is tested under both photon and neutron irradiations, allowing us to investigate the performance of the overall compensation system in terms of neutron detection, especially with regards to a commercial helium-3 counter. The study reveals satisfactory results in terms of sensitivity and orientates future investigation toward promising axes. (authors)« less

Magnetic Particle Imaging (MPI) for NMR and MRI researchers

NASA Astrophysics Data System (ADS)

Saritas, Emine U.; Goodwill, Patrick W.; Croft, Laura R.; Konkle, Justin J.; Lu, Kuan; Zheng, Bo; Conolly, Steven M.

2013-04-01

Magnetic Particle Imaging (MPI) is a new tracer imaging modality that is gaining significant interest from NMR and MRI researchers. While the physics of MPI differ substantially from MRI, it employs hardware and imaging concepts that are familiar to MRI researchers, such as magnetic excitation and detection, pulse sequences, and relaxation effects. Furthermore, MPI employs the same superparamagnetic iron oxide (SPIO) contrast agents that are sometimes used for MR angiography and are often used for MRI cell tracking studies. These SPIOs are much safer for humans than iodine or gadolinium, especially for Chronic Kidney Disease (CKD) patients. The weak kidneys of CKD patients cannot safely excrete iodine or gadolinium, leading to increased morbidity and mortality after iodinated X-ray or CT angiograms, or after gadolinium-MRA studies. Iron oxides, on the other hand, are processed in the liver, and have been shown to be safe even for CKD patients. Unlike the “black blood” contrast generated by SPIOs in MRI due to increased T2∗ dephasing, SPIOs in MPI generate positive, “bright blood” contrast. With this ideal contrast, even prototype MPI scanners can already achieve fast, high-sensitivity, and high-contrast angiograms with millimeter-scale resolutions in phantoms and in animals. Moreover, MPI shows great potential for an exciting array of applications, including stem cell tracking in vivo, first-pass contrast studies to diagnose or stage cancer, and inflammation imaging in vivo. So far, only a handful of prototype small-animal MPI scanners have been constructed worldwide. Hence, MPI is open to great advances, especially in hardware, pulse sequence, and nanoparticle improvements, with the potential to revolutionize the biomedical imaging field.

Applying Amide Proton Transfer MR Imaging to Hybrid Brain PET/MR: Concordance with Gadolinium Enhancement and Added Value to [18F]FDG PET.

PubMed

Sun, Hongzan; Xin, Jun; Zhou, Jinyuan; Lu, Zaiming; Guo, Qiyong

2018-06-01

The purpose of this study is to evaluate the diagnostic concordance and metric correlations of amide proton transfer (APT) imaging with gadolinium-enhanced magnetic resonance imaging (MRI) and 2-deoxy-2-[ 18 F-]fluoro-D-glucose ([ 18 F]FDG) positron emission tomography (PET), using hybrid brain PET/MRI. Twenty-one subjects underwent brain gadolinium-enhanced [ 18 F]FDG PET/MRI prospectively. Imaging accuracy was compared between unenhanced MRI, MRI with enhancement, APT-weighted (APTW) images, and PET based on six diagnostic criteria. Among tumors, the McNemar test was further used for concordance assessment between gadolinium-enhanced imaging, APT imaging, and [ 18 F]FDG PET. As well, the relation of metrics between APT imaging and PET was analyzed by the Pearson correlation analysis. APT imaging and gadolinium-enhanced MRI showed superior and similar diagnostic accuracy. APTW signal intensity and gadolinium enhancement were concordant in 19 tumors (100 %), while high [ 18 F]FDG avidity was shown in only 12 (63.2 %). For the metrics from APT imaging and PET, there was significant correlation for 13 hypermetabolic tumors (P < 0.05) and no correlation for the remaining six [ 18 F]FDG-avid tumors. APT imaging can be used to increase diagnostic accuracy with no need to administer gadolinium chelates. APT imaging may provide an added value to [ 18 F]FDG PET in the evaluation of tumor metabolic activity during brain PET/MR studies.

The Incidence of Complications in Single-stage Endoscopic Stone Removal for Patients with Common Bile Duct Stones: A Propensity Score Analysis.

PubMed

Saito, Hirokazu; Kadono, Yoshihiro; Kamikawa, Kentaro; Urata, Atsushi; Imamura, Haruo; Matsushita, Ikuo; Kakuma, Tatsuyuki; Tada, Shuji

2018-02-15

Objective Single-stage endoscopic stone removal for choledocholithiasis is an advantageous approach because it is associated with a shorter hospital stay; however, few studies have reported the incidence of complications related to this procedure in detail. The aim of this study was to examine the incidence of complications and efficacy of this procedure. Methods This retrospective study investigated the incidence of complications in 345 patients with naive papilla who underwent therapeutic endoscopic retrograde cholangiopancreatography (ERCP) for choledocholithiasis at three institutions between April 2014 and March 2016 by a propensity score analysis. The efficacy of single-stage endoscopic stone removal was assessed based on a hospital stay of within 7 days and the number of ERCP attempts. Results Among 114 patients who underwent single-stage endoscopic stone removal, 15 patients (13.2%) experienced complications. Among the remaining 231 patients in the two-stage endoscopic stone removal group, complications were observed in 17 patients (7.4%). The propensity score analysis, which was adjusted for confounding factors, revealed that single-stage endoscopic stone removal was not a significant risk factor for complications (p=0.52). In patients in whom >10 min was required for deep cannulation, single-stage endoscopic stone removal was not a significant risk factor for complications in the propensity score analysis (p=0.37). In the single-stage group, the proportion of patients with a hospital stay of within 7 days was significantly higher and the number of ERCP attempts was significantly lower in comparison to the two-stage group (p <0.0001 and <0.0001, respectively). Conclusion Single-stage endoscopic stone removal did not increase the incidence of complications associated with ERCP and was effective for reducing the hospital stay and the number of ERCP attempts.

The Incidence of Complications in Single-stage Endoscopic Stone Removal for Patients with Common Bile Duct Stones: A Propensity Score Analysis

PubMed Central

Saito, Hirokazu; Kadono, Yoshihiro; Kamikawa, Kentaro; Urata, Atsushi; Imamura, Haruo; Matsushita, Ikuo; Kakuma, Tatsuyuki; Tada, Shuji

2017-01-01

Objective Single-stage endoscopic stone removal for choledocholithiasis is an advantageous approach because it is associated with a shorter hospital stay; however, few studies have reported the incidence of complications related to this procedure in detail. The aim of this study was to examine the incidence of complications and efficacy of this procedure. Methods This retrospective study investigated the incidence of complications in 345 patients with naive papilla who underwent therapeutic endoscopic retrograde cholangiopancreatography (ERCP) for choledocholithiasis at three institutions between April 2014 and March 2016 by a propensity score analysis. The efficacy of single-stage endoscopic stone removal was assessed based on a hospital stay of within 7 days and the number of ERCP attempts. Results Among 114 patients who underwent single-stage endoscopic stone removal, 15 patients (13.2%) experienced complications. Among the remaining 231 patients in the two-stage endoscopic stone removal group, complications were observed in 17 patients (7.4%). The propensity score analysis, which was adjusted for confounding factors, revealed that single-stage endoscopic stone removal was not a significant risk factor for complications (p=0.52). In patients in whom >10 min was required for deep cannulation, single-stage endoscopic stone removal was not a significant risk factor for complications in the propensity score analysis (p=0.37). In the single-stage group, the proportion of patients with a hospital stay of within 7 days was significantly higher and the number of ERCP attempts was significantly lower in comparison to the two-stage group (p <0.0001 and <0.0001, respectively). Conclusion Single-stage endoscopic stone removal did not increase the incidence of complications associated with ERCP and was effective for reducing the hospital stay and the number of ERCP attempts. PMID:29151506

Distribution of late gadolinium enhancement in various types of cardiomyopathies: Significance in differential diagnosis, clinical features and prognosis.

PubMed

Satoh, Hiroshi; Sano, Makoto; Suwa, Kenichiro; Saitoh, Takeji; Nobuhara, Mamoru; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Hayashi, Hideharu

2014-07-26

The recent development of cardiac magnetic resonance (CMR) techniques has allowed detailed analyses of cardiac function and tissue characterization with high spatial resolution. We review characteristic CMR features in ischemic and non-ischemic cardiomyopathies (ICM and NICM), especially in terms of the location and distribution of late gadolinium enhancement (LGE). CMR in ICM shows segmental wall motion abnormalities or wall thinning in a particular coronary arterial territory, and the subendocardial or transmural LGE. LGE in NICM generally does not correspond to any particular coronary artery distribution and is located mostly in the mid-wall to subepicardial layer. The analysis of LGE distribution is valuable to differentiate NICM with diffusely impaired systolic function, including dilated cardiomyopathy, end-stage hypertrophic cardiomyopathy (HCM), cardiac sarcoidosis, and myocarditis, and those with diffuse left ventricular (LV) hypertrophy including HCM, cardiac amyloidosis and Anderson-Fabry disease. A transient low signal intensity LGE in regions of severe LV dysfunction is a particular feature of stress cardiomyopathy. In arrhythmogenic right ventricular cardiomyopathy/dysplasia, an enhancement of right ventricular (RV) wall with functional and morphological changes of RV becomes apparent. Finally, the analyses of LGE distribution have potentials to predict cardiac outcomes and response to treatments.

Micellar casein concentrate production with a 3X, 3-stage, uniform transmembrane pressure ceramic membrane process at 50°C.

PubMed

Hurt, E; Zulewska, J; Newbold, M; Barbano, D M

2010-12-01

The production of serum protein (SP) and micellar casein from skim milk can be accomplished using microfiltration (MF). Potential commercial applications exist for both SP and micellar casein. Our research objective was to determine the total SP removal and SP removal for each stage, and the composition of retentates and permeates, for a 3×, continuous bleed-and-feed, 3-stage, uniform transmembrane pressure (UTP) system with 0.1-μm ceramic membranes, when processing pasteurized skim milk at 50°C with 2 stages of water diafiltration. For each of 4 replicates, about 1,100 kg of skim milk was pasteurized (72°C, 16s) and processed at 3× through the UTP MF system. Retentate from stage 1 was cooled to <4°C and stored until the next processing day, when it was diluted with reverse osmosis water back to a 1× concentration and again processed through the MF system (stage 2) to a 3× concentration. The retentate from stage 2 was stored at <4°C, and, on the next processing day, was diluted with reverse osmosis water back to a 1× concentration, before running through the MF system at 3× for a total of 3 stages. The retentate and permeate from each stage were analyzed for total nitrogen, noncasein nitrogen, and nonprotein nitrogen using Kjeldahl methods; sodium dodecyl sulfate-PAGE analysis was also performed on the retentates from each stage. Theoretically, a 3-stage, 3× MF process could remove 97% of the SP from skim milk, with a cumulative SP removal of 68 and 90% after the first and second stages, respectively. The cumulative SP removal using a 3-stage, 3× MF process with a UTP system with 0.01-μm ceramic membranes in this experiment was 64.8 ± 0.8, 87.8 ± 1.6, and 98.3 ± 2.3% for the first, second, and third stages, respectively, when calculated using the mass of SP removed in the permeate of each stage. Various methods of calculation of SP removal were evaluated. Given the analytical limitations in the various methods for measuring SP removal, calculation of SP removal based on the mass of SP in the skim milk (determined by Kjeldahl) and the mass SP present in all of the permeate produced by the process (determined by Kjeldahl) provided the best estimate of SP removal for an MF process. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Myocardial Damage Detected by Late Gadolinium Enhancement Cardiovascular Magnetic Resonance Is Associated With Subsequent Hospitalization for Heart Failure

PubMed Central

Wong, Timothy C.; Piehler, Kayla M.; Zareba, Karolina M.; Lin, Kathie; Phrampus, Ashley; Patel, Agam; Moon, James C.; Ugander, Martin; Valeti, Uma; Holtz, Jonathan E.; Fu, Bo; Chang, Chung‐Chou H.; Mathier, Michael; Kellman, Peter; Butler, Javed; Gheorghiade, Mihai; Schelbert, Erik B.

2013-01-01

Background Hospitalization for heart failure (HHF) is among the most important problems confronting medicine. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) robustly identifies intrinsic myocardial damage. LGE may indicate inherent vulnerability to HHF, regardless of etiology, across the spectrum of heart failure stage or left ventricular ejection fraction (LVEF). Methods and Results We enrolled 1068 consecutive patients referred for CMR where 448 (42%) exhibited LGE. After a median of 1.4 years (Q1 to Q3: 0.9 to 2.0 years), 57 HHF events occurred, 15 deaths followed HHF, and 43 deaths occurred without antecedent HHF (58 total deaths). Using multivariable Cox regression adjusting for LVEF, heart failure stage, and other covariates, LGE was associated with first HHF after CMR (HR: 2.70, 95% CI: 1.32 to 5.50), death (HR: 2.13, 95% CI: 1.08 to 4.21), or either death or HHF (HR: 2.52, 95% CI: 1.49 to 4.25). Quantifying LGE extent yielded similar results; more LGE equated higher risks. LGE improved model discrimination (IDI: 0.016, 95% CI: 0.005 to 0.028, P=0.002) and reclassification of individuals at risk (continuous NRI: 0.40, 95% CI: 0.05 to 0.70, P=0.024). Adjustment for competing risks of death that shares common risk factors with HHF strengthened the LGE and HHF association (HR: 4.85, 95% CI: 1.40 to 16.9). Conclusions The presence and extent of LGE is associated with vulnerability for HHF, including higher risks of HHF across the spectrum of heart failure stage and LVEF. Even when LVEF is severely decreased, those without LGE appear to fare reasonably well. LGE may enhance risk stratification for HHF and may enhance both clinical and research efforts to reduce HHF through targeted treatment. PMID:24249712

ZnO:Gd nanocrystals for fluorescent applications

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

Divya, N. K., E-mail: divyank90@gmail.com; Pradyumnan, P. P.

2016-05-23

Gadolinium doped ZnO crystals within the solubility limit of gadolinium in ZnO matrix were prepared by solid state reaction technique. The method is relatively less expense and enables the production in large scale. The samples were characterised by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), UV/Vis diffuse reflectance spectroscopy and photoluminescence techniques. Fluorescent property studies of gadolinium doped ZnO at room temperature show enhanced visible light emission due to the defects and oxygen vacancies produced via doping. This work reports the impact of gadolinium doping in the structural, optical and luminescent properties of ZnO inmore » detail.« less

Are gadolinium-based contrast media nephrotoxic? A renal biopsy study.

PubMed

Akgun, Hulya; Gonlusen, Gulfiliz; Cartwright, Joiner; Suki, Wadi N; Truong, Luan D

2006-09-01

Gadolinium-based contrast media were originally introduced as alternatives to iodinated media for magnetic resonance imaging. Although originally thought to be nonnephrotoxic, gadolinium-based contrast media have recently been reported to be associated with acute renal failure; the mechanism and the underlying renal injury are not completely understood. We report what is, to our knowledge, the first renal biopsy in this context. A 56-year-old patient underwent 2 consecutive vascular imaging procedures in conjunction with gadolinium-based contrast medium administration. A few days later, the patient developed acute renal failure. A renal biopsy showed acute tubular cell injury including patchy tubular cell necrosis, tubular cell degeneration, and marked proliferation of tubular cells, together with mild interstitial edema and interstitial inflammation, but without significant glomerular or vascular changes. During supportive therapy, renal function was partially regained. This case emphasizes the potential nephrotoxicity of gadolinium-based contrast media and suggests that the nephrotoxicity is related to potentially reversible acute tubular cell injury.

In vitro study of novel gadolinium-loaded liposomes guided by GBI-10 aptamer for promising tumor targeting and tumor diagnosis by magnetic resonance imaging.

PubMed

Gu, Meng-Jie; Li, Kun-Feng; Zhang, Lan-Xin; Wang, Huan; Liu, Li-Si; Zheng, Zhuo-Zhao; Han, Nan-Yin; Yang, Zhen-Jun; Fan, Tian-Yuan

2015-01-01

Novel gadolinium-loaded liposomes guided by GBI-10 aptamer were developed and evaluated in vitro to enhance magnetic resonance imaging (MRI) diagnosis of tumor. Nontargeted gadolinium-loaded liposomes were achieved by incorporating amphipathic material, Gd (III) [N,N-bis-stearylamidomethyl-N'-amidomethyl] diethylenetriamine tetraacetic acid, into the liposome membrane using lipid film hydration method. GBI-10, as the targeting ligand, was then conjugated onto the liposome surface to get GBI-10-targeted gadolinium-loaded liposomes (GTLs). Both nontargeted gadolinium-loaded liposomes and GTLs displayed good dispersion stability, optimal size, and zeta potential for tumor targeting, as well as favorable imaging properties with enhanced relaxivity compared with a commercial MRI contrast agent (CA), gadopentetate dimeglumine. The use of GBI-10 aptamer in this liposomal system was intended to result in increased accumulation of gadolinium at the periphery of C6 glioma cells, where the targeting extracellular matrix protein tenascin-C is overexpressed. Increased cellular binding of GTLs to C6 cells was confirmed by confocal microscopy, flow cytometry, and MRI, demonstrating the promise of this novel delivery system as a carrier of MRI contrast agent for the diagnosis of tumor. These studies provide a new strategy furthering the development of nanomedicine for both diagnosis and therapy of tumor.

Tracing gadolinium-based contrast agents from surface water to drinking water by means of speciation analysis.

PubMed

Birka, Marvin; Wehe, Christoph A; Hachmöller, Oliver; Sperling, Michael; Karst, Uwe

2016-04-01

In recent decades, a significant amount of anthropogenic gadolinium has been released into the environment as a result of the broad application of contrast agents for magnetic resonance imaging (MRI). Since this anthropogenic gadolinium anomaly has also been detected in drinking water, it has become necessary to investigate the possible effect of drinking water purification on these highly polar microcontaminats. Therefore, a novel highly sensitive method for speciation analysis of gadolinium is presented. For that purpose, the hyphenation of hydrophilic interaction liquid chromatography (HILIC) and inductively coupled plasma-mass spectrometry (ICP-MS) was employed. In order to enhance the detection power, sample introduction was carried out by ultrasonic nebulization. In combination with a novel HILIC method using a diol-based stationary phase, it was possible to achieve superior limits of detection for frequently applied gadolinium-based contrast agents below 20pmol/L. With this method, the contrast agents Gd-DTPA, Gd-DOTA and Gd-BT-DO3A were determined in concentrations up to 159pmol/L in samples from several waterworks in a densely populated region of Germany alongside the river Ruhr as well as from a waterworks near a catchment lake. Thereby, the direct impact of anthropogenic gadolinium species being present in the surface water on the amount of anthropogenic gadolinium in drinking water was shown. There was no evidence for the degradation of contrast agents, the release of Gd(3+) or the presence of further Gd species. Copyright © 2016 Elsevier B.V. All rights reserved.

75 FR 59067 - Airworthiness Directives; International Aero Engines AG V2500-A1, V2522-A5, V2524-A5, V2525-D5...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-27

... plated nuts attaching the HPC stage 3 to 8 drum to the HPC stage 9 to 12 drum, removal of silver residue... plated nuts attaching the HPC stage 3 to 8 drum to the HPC stage 9 to 12 drum, removal of silver residue... AD, removal from service of the fully silver plated nuts attaching the HPC stage 3 to 8 drum to the...

Gadolinium Chelate Safety in Pregnancy: Barely Detectable Gadolinium Levels in the Juvenile Nonhuman Primate after in Utero Exposure.

PubMed

Prola-Netto, Joao; Woods, Mark; Roberts, Victoria H J; Sullivan, Elinor L; Miller, Christina Ann; Frias, Antonio E; Oh, Karen Y

2018-01-01

Purpose To determine whether gadolinium remains in juvenile nonhuman primate tissue after maternal exposure to intravenous gadoteridol during pregnancy. Materials and Methods Gravid rhesus macaques and their offspring (n = 10) were maintained, as approved by the institutional animal care and utilization committee. They were prospectively studied as part of a pre-existing ongoing research protocol to evaluate the effects of maternal malnutrition on placental and fetal development. On gestational days 85 and 135, they underwent placental magnetic resonance imaging after intravenous gadoteridol administration. Amniocentesis was performed on day 135 prior to administration of the second dose of gadoteridol. After delivery, the offspring were followed for 7 months. Tissue samples from eight different organs and from blood were harvested from each juvenile macaque. Gadolinium levels were measured by using inductively coupled plasma mass spectrometry. Results Gadolinium concentration in the amniotic fluid was 0.028 × 10 -5 %ID/g (percentage injected dose per gram of tissue) 50 days after administration of one gadoteridol dose. Gadolinium was most consistently detected in the femur (mean, 2.5 × 10 -5 %ID/g; range, [0.81-4.1] × 10 -5 %ID/g) and liver (mean, 0.15 × 10 -5 %ID/g; range, [0-0.26] × 10 -5 %ID/g). Levels were undetectable in the remaining sampled tissues, with the exception of one juvenile skin sample (0.07 × 10 -5 %ID/g), one juvenile spleen sample (0.039 × 10 -5 %ID/g), and one juvenile brain (0.095 × 10 -5 %ID/g) and kidney (0.13 × 10 -5 %ID/g) sample. Conclusion The presence of gadoteridol in the amniotic fluid after maternal injection enables confirmation that it crosses the placenta. Extremely low levels of gadolinium are found in juvenile macaque tissues after in utero exposure to two doses of gadoteridol, indicating that a very small amount of gadolinium persists after delivery. © RSNA, 2017.

Gadolinium accumulation in organs of Sprague-Dawley® rats after implantation of a biodegradable magnesium-gadolinium alloy.

PubMed

Myrissa, Anastasia; Braeuer, Simone; Martinelli, Elisabeth; Willumeit-Römer, Regine; Goessler, Walter; Weinberg, Annelie Martina

2017-01-15

Biodegradable magnesium implants are under investigation because of their promising properties as medical devices. For enhancing the mechanical properties and the degradation resistance, rare earth elements are often used as alloying elements. In this study Mg10Gd pins were implanted into Sprague-Dawley® rats. The pin volume loss and a possible accumulation of magnesium and gadolinium in the rats' organs and blood were investigated in a long-term study over 36weeks. The results showed that Mg10Gd is a fast disintegrating material. Already 12weeks after implantation the alloy is fragmented to smaller particles, which can be found within the intramedullary cavity and the cortical bones. They disturbed the bone remodeling until the end of the study. The results concerning the elements' distribution in the animals' bodies were even more striking, since an accumulation of gadolinium could be observed in the investigated organs over the whole time span. The most affected tissue was the spleen, with up to 3240μgGd/kg wet mass, followed by the lung, liver and kidney (up to 1040, 685 and 207μgGd/kg). In the brain, muscle and heart, the gadolinium concentrations were much smaller (less than 20μg/kg), but an accumulation could still be detected. Interestingly, blood serum samples showed no accumulation of magnesium and gadolinium. This is the first time that an accumulation of gadolinium in animal organs was observed after the application of a gadolinium-containing degradable magnesium implant. These findings demonstrate the importance of future investigations concerning the distribution of the constituents of new biodegradable materials in the body, to ensure the patients' safety. In the last years, biodegradable Mg alloys are under investigation due to their promising properties as orthopaedic devices used for bone fracture stabilization. Gadolinium as Rare Earth Element enhances the mechanical properties of Mg-Gd alloys but its toxicity in humans is still questionable. Up to now, there is no study investigating the elements' metabolism of a REE-containing Magnesium alloy in an animal model. In this study, we examined the gadolinium distribution and accumulation in rat organs during the degradation of Mg10Gd. Our findings showed that Gd is accumulating in the animal organs, especially in spleen, liver and kidney. This study is of crucial benefit regarding a safe application of REE-containing Magnesium alloys in humans. Copyright © 2016. Published by Elsevier Ltd.

Long-term follow-up of callotasis lengthening of the capitate after resection of the lunate for the treatment of stage III lunate necrosis.

PubMed

Hierner, Robert; Wilhelm, Klaus

2010-04-01

The callotasis lengthening technique was used to gradually lengthen the capitate after resection of the lunate in stage IIIa necrosis in 23 patients. Results of ten patients with a follow-up of at least 5 years showed rapid and sufficient callus formation in every patient regardless of age. The callotasis lengthening modification of the Graner II operation provides all advantages and avoids the major inconvenience of the traditional Graner II operation. There was no increased rate of disturbed fracture healing. Results of the DTPA-gadolinium MRI study did not show any significant impairment of vascularization within the region of the capitate bone. With the "intrinsic bone formation," contrary to every other intercarpal arthrodesis at the wrist, there is no need for an additional bone graft.

Nitrogen and phosphorus removed from a subsurface flow multi-stage filtration system purifying agricultural runoff.

PubMed

Zhao, Yaqi; Huang, Lei; Chen, Yucheng

2018-07-01

Agricultural nonpoint source pollution has been increasingly serious in China since the 1990s. The main causes were excessive inputs of nitrogen fertilizer and pesticides. A multi-stage filtration system was built to test the purification efficiencies and removal characteristics of nitrogen and phosphorus when treating agricultural runoff. Simulated runoff pollution was prepared by using river water as source water based on the monitoring of local agricultural runoff. Experimental study had been performed from September to November 2013, adopting 12 h for flooding and 12 h for drying. The results showed that the system was made adaptive to variation of inflow quality and quantity, and had good removal for dissolved total nitrogen, total nitrogen, dissolved total phosphorus (DTP), and total phosphorus, and the average removal rate was 27%, 36%, 32%, and 48%, respectively. Except nitrate ([Formula: see text]), other forms of nitrogen and phosphorus all decreased with the increase of stages. Nitrogen was removed mainly in particle form the first stage, and mostly removed in dissolved form the second and third stage. Phosphorus was removed mainly in particulate during the first two stages, but the removal of particulate phosphorus and DTP were almost the same in the last stage. An approximate logarithmic relationship between removal loading and influent loading to nitrogen and phosphorus was noted in the experimental system, and the correlation coefficient was 0.78-0.94. [Formula: see text]: ammonium; [Formula: see text]: nitrite; [Formula: see text]: nitrate; DTN: dissolved total nitrogen; TN: total nitrogen; DTP: dissolved total phosphorus; TP: total phosphorus; PN: particulate nitrogen; PP: particulate phosphorus.

Silica nanoparticle-based dual imaging colloidal hybrids: cancer cell imaging and biodistribution

PubMed Central

Lee, Haisung; Sung, Dongkyung; Kim, Jinhoon; Kim, Byung-Tae; Wang, Tuntun; An, Seong Soo A; Seo, Soo-Won; Yi, Dong Kee

2015-01-01

In this study, fluorescent dye-conjugated magnetic resonance (MR) imaging agents were investigated in T mode. Gadolinium-conjugated silica nanoparticles were successfully synthesized for both MR imaging and fluorescence diagnostics. Polyamine and polycarboxyl functional groups were modified chemically on the surface of the silica nanoparticles for efficient conjugation of gadolinium ions. The derived gadolinium-conjugated silica nanoparticles were investigated by zeta potential analysis, transmission electron microscopy, inductively coupled plasma mass spectrometry, and energy dispersive x-ray spectroscopy. MR equipment was used to investigate their use as contrast-enhancing agents in T1 mode under a 9.4 T magnetic field. In addition, we tracked the distribution of the gadolinium-conjugated nanoparticles in both lung cancer cells and organs in mice. PMID:26357472

Gadolinium oxide decorated multiwalled carbon nanotube/tridoped titania nanocomposites for improved dye degradation under simulated solar light irradiation

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

Mamba, Gcina; Nanotechnology and Water Sustainability Research Unit, College of Engineering, Science and Technology, University of South Africa Florida Science Campus, 1709 Florida; Mbianda, Xavier Yangkou

2016-03-15

Graphical abstract: Illustration of the collaborative effect between MWCNT-Gd and Gd,N,S-TiO{sub 2} towards degradation of AB 74. - Highlights: • MWCNT-Gd/tridoped titania was successfully prepared via a sol-gel method. • XPS revealed the presence of Ti, C, O, S, N and Gd in MWCNT-Gd/Gd,N,S-TiO{sub 2}. • MWCNT-Gd/Gd,N,S-TiO{sub 2} displayed 100% degradation of acid blue 74 in 150 min. • Over 60% TOC removal by MWCNT-Gd/Gd,N,S-TiO{sub 2}. - Abstract: Neodymium/gadolinium/europium, nitrogen and sulphur tridoped titania (Nd/Gd/Eu, N,S-TiO{sub 2}) was hybridised with pre-synthesised gadolinium oxide decorated multiwalled carbon nanotubes (MWCNT-Gd) using a sol–gel method. Subsequent to drying and calcination, composite photocatalysts: MWCNT-Gd/Nd,N,S-TiO{submore » 2}, MWCNT-Gd/Gd,N,S-TiO{sub 2} and MWCNT-Gd/Eu,N,S-TiO{sub 2}, were obtained and characterised using TEM, SEM-EDX, UV–vis, XPS, XRD and FT-IR. Acid blue 74 (AB74) was used as a model dye to investigate the photocatalytic degradation properties of the prepared materials under simulated solar light irradiation. Coupling the different tridoped titania with MWCNT-Gd enhanced their activity compared to MWCNT/TiO{sub 2}, MWCNT-Gd/TiO{sub 2} and MWCNT/Gd,N,S-TiO{sub 2}. MWCNT-Gd/Gd,N,S-TiO{sub 2} showed the highest activity towards AB74 degradation reaching 100% decolourisation after 150 min of irradiation. Total organic carbon analysis revealed that over 50% of the AB74 molecules were completely mineralised after 180 min of irradiation in the presence of MWCNT-Gd/Gd,N,S-TiO{sub 2}.« less

Production efficiency of micellar casein concentrate using polymeric spiral-wound microfiltration membranes.

PubMed

Beckman, S L; Zulewska, J; Newbold, M; Barbano, D M

2010-10-01

Most current research has focused on using ceramic microfiltration (MF) membranes for micellar casein concentrate production, but little research has focused on the use of polymeric spiral-wound (SW) MF membranes. A method for the production of a serum protein (SP)-reduced micellar casein concentrate using SW MF was compared with a ceramic MF membrane. Pasteurized (79°C, 18s) skim milk (1,100 kg) was microfiltered at 50°C [about 3 × concentration] using a 0.3-μm polyvinylidene fluoride spiral-wound membrane, bleed-and-feed, 3-stage process, using 2 diafiltration stages, where the retentate was diluted 1:2 with reverse osmosis water. Skim milk, permeate, and retentate were analyzed for SP content, and the reduction of SP from skim milk was determined. Theoretically, 68% of the SP content of skim milk can be removed using a single-stage 3× MF. If 2 subsequent water diafiltration stages are used, an additional 22% and 7% of the SP can be removed, respectively, giving a total SP removal of 97%. Removal of SP greater than 95% has been achieved using a 0.1-μm pore size ceramic uniform transmembrane pressure (UTP) MF membrane after a 3-stage MF with diafiltration process. One stage of MF plus 2 stages of diafiltration of 50°C skim milk using a polyvinylidene fluoride polymeric SW 0.3-μm membrane yielded a total SP reduction of only 70.3% (stages 1, 2, and 3: 38.6, 20.8, and 10.9%, respectively). The SP removal rate for the polymeric SW MF membrane was lower in all 3 stages of processing (stages 1, 2, and 3: 0.05, 0.04, and 0.03 kg/m(2) per hour, respectively) than that of the comparable ceramic UTP MF membrane (stages 1, 2, and 3: 0.30, 0.11, and 0.06 kg/m(2) per hour, respectively), indicating that SW MF is less efficient at removing SP from 50°C skim milk than the ceramic UTP system. To estimate the number of steps required for the SW system to reach 95% SP removal, the third-stage SP removal rate (27.4% of the starting material SP content) was used to extrapolate that an additional 5 water diafiltration stages would be necessary, for a total of 8 stages, to remove 95% of the SP from skim milk. The 8-plus stages necessary to remove >95% SP for the SW MF membrane would create more permeate and a lengthier process than required with ceramic membranes. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Two-stage anaerobic digestion enables heavy metal removal.

PubMed

Selling, Robert; Håkansson, Torbjörn; Björnsson, Lovisa

2008-01-01

To fully exploit the environmental benefits of the biogas process, the digestate should be recycled as biofertiliser to agriculture. This practice can however be jeopardized by the presence of unwanted compounds such as heavy metals in the digestate. By using two-stage digestion, where the first stage includes hydrolysis/acidification and liquefaction of the substrate, heavy metals can be transferred to the leachate. From the leachate, metals can then be removed by adsorption. In this study, up to 70% of the Ni, 40% of the Zn and 25% of the Cd present in maize was removed when the leachate from hydrolysis was circulated over a macroporous polyacrylamide column for 6 days. For Cu and Pb, the mobilization in the hydrolytic stage was lower which resulted in a low removal. A more efficient two-stage process with improved substrate hydrolysis would give lower pH and/or longer periods with low pH in the hydrolytic stage. This is likely to increase metal mobilisation, and would open up for an excellent opportunity of heavy metal removal.

Dual-contrast agent photon-counting computed tomography of the heart: initial experience.

PubMed

Symons, Rolf; Cork, Tyler E; Lakshmanan, Manu N; Evers, Robert; Davies-Venn, Cynthia; Rice, Kelly A; Thomas, Marvin L; Liu, Chia-Ying; Kappler, Steffen; Ulzheimer, Stefan; Sandfort, Veit; Bluemke, David A; Pourmorteza, Amir

2017-08-01

To determine the feasibility of dual-contrast agent imaging of the heart using photon-counting detector (PCD) computed tomography (CT) to simultaneously assess both first-pass and late enhancement of the myocardium. An occlusion-reperfusion canine model of myocardial infarction was used. Gadolinium-based contrast was injected 10 min prior to PCD CT. Iodinated contrast was infused immediately prior to PCD CT, thus capturing late gadolinium enhancement as well as first-pass iodine enhancement. Gadolinium and iodine maps were calculated using a linear material decomposition technique and compared to single-energy (conventional) images. PCD images were compared to in vivo and ex vivo magnetic resonance imaging (MRI) and histology. For infarct versus remote myocardium, contrast-to-noise ratio (CNR) was maximal on late enhancement gadolinium maps (CNR 9.0 ± 0.8, 6.6 ± 0.7, and 0.4 ± 0.4, p < 0.001 for gadolinium maps, single-energy images, and iodine maps, respectively). For infarct versus blood pool, CNR was maximum for iodine maps (CNR 11.8 ± 1.3, 3.8 ± 1.0, and 1.3 ± 0.4, p < 0.001 for iodine maps, gadolinium maps, and single-energy images, respectively). Combined first-pass iodine and late gadolinium maps allowed quantitative separation of blood pool, scar, and remote myocardium. MRI and histology analysis confirmed accurate PCD CT delineation of scar. Simultaneous multi-contrast agent cardiac imaging is feasible with photon-counting detector CT. These initial proof-of-concept results may provide incentives to develop new k-edge contrast agents, to investigate possible interactions between multiple simultaneously administered contrast agents, and to ultimately bring them to clinical practice.

A study on the imaging characteristics of Gold nanoparticles as a contrast agent in X-ray computed tomography

NASA Astrophysics Data System (ADS)

Mesbahi, Asghar; Famouri, Fatemeh; Ahar, Mohammad Johari; Ghaffari, Maryam Olade; Ghavami, Seyed Mostafa

2017-03-01

Aim: In the current study, some imaging characteristics of AuNPs were quantitatively analyzed and compared with two conventional contrast media (CM) including Iodine and Gadolinium by using of a cylindrical phantom. Methods: AuNPs were synthesized with the mean diameter of 16 nm and were equalized to the concentration of 0.5, 1, 2 and 4 mg/mL in the same volumes. A cylindrical phantom resembling the head and neck was fabricated and drilled to contain small tubes filled with Iodine, Gadolinium, and AuNPs as contrast media. The phantom was scanned in different exposure techniques and CT numbers of three studied contrast media inside test tubes were measured in terms of Hounsfield Unit (HU). The imaging parameters of the noise and contrast to noise ratios (CNR) were calculated for all studied CMs. Results: AuNPs showed 128% and 166% higher CT number in comparison with Iodine and Gadolinium respectively. Also, Iodine had a greater CT number than Gadolinium for the same exposure techniques and concentration. The maximum CT number for AuNPs and studied contrast materials was obtained at the highest mAs and the lowest tube potential. The maximum CT number were 1033±11 (HU) for AuNP, 565±10 (HU) for Iodine, 458±11 for Gadolinium. Moreover, the maximum CNRs of 433±117, 203±53, 145±37 were found for AuNPs, Iodine and Gadolinium respectively. Conclusion: The contrast agent based on AuNPs showed higher imaging quality in terms of contrast and noise relative to other iodine and gadolinium based contrast media in X-ray computed tomography. Application of the AuNPs as a contrast medium in x-ray CT is recommended.

Polythermal investigation of viscosity of solution of metal carboxylates in VIK-grade mixed carboxylic acids: Yttrium and gadolinium carboxylates

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

Mezhov, E.A.; Samatov, A.V.; Troyanovskii, L.V.

Kinematic viscosities have been measured for solutions of yttrium and gadolinium carboxylates in grade VIK mixed carboxylic acids (MCA). It has been established that the optimal fluidity of these metal carboxylate solutions for application to articles is reached at 333 K. A regression model has been developed to describe the concentration and temperature dependences of the viscosity of yttrium- and gadolinium-containing MCA solutions. 2 refs., 3 tabs.

Gadolinium deposition disease: Initial description of a disease that has been around for a while.

PubMed

Semelka, Richard C; Ramalho, Joana; Vakharia, Ami; AlObaidy, Mamdoh; Burke, Lauren M; Jay, Michael; Ramalho, Miguel

2016-12-01

To describe the clinical manifestations of presumed gadolinium toxicity in patients with normal renal function. Participants were recruited from two online gadolinium toxicity support groups. The survey was anonymous and individuals were instructed to respond to the survey only if they had evidence of normal renal function, evidence of gadolinium in their system beyond 30days of this MRI, and no pre-existent clinical symptoms and/or signs of this type. 42 subjects responded to the survey (age: 28-69, mean 49.1±22.4years). The most common findings were: central pain (n=15), peripheral pain (n=26), headache (n=28), and bone pain (n=26). Only subjects with distal leg and arm distribution described skin thickening (n=22). Clouded mentation and headache were the symptoms described as persistent beyond 3months in 29 subjects. Residual disease was present in all patients. Twenty-eight patients described symptoms following administration of one brand of Gadolinium-Based Contrast Agent (GBCA), 21 after a single GBCA administration and 7 after multiple GBCA administrations, including: gadopentetate dimeglumine, n=9; gadodiamide, n=4; gadoversetamide, n=4; gadobenate dimeglumine, n=4; gadobutrol, n=1; gadoteridol, n=2; and unknown, n=4. Gadolinium toxicity appears to arise following GBCA administration, which appears to contain clinical features seen in Nephrogenic Systemic Fibrosis, but also features not observed in that condition. Copyright © 2016 Elsevier Inc. All rights reserved.

In vitro study of novel gadolinium-loaded liposomes guided by GBI-10 aptamer for promising tumor targeting and tumor diagnosis by magnetic resonance imaging

PubMed Central

Gu, Meng-Jie; Li, Kun-Feng; Zhang, Lan-Xin; Wang, Huan; Liu, Li-Si; Zheng, Zhuo-Zhao; Han, Nan-Yin; Yang, Zhen-Jun; Fan, Tian-Yuan

2015-01-01

Novel gadolinium-loaded liposomes guided by GBI-10 aptamer were developed and evaluated in vitro to enhance magnetic resonance imaging (MRI) diagnosis of tumor. Nontargeted gadolinium-loaded liposomes were achieved by incorporating amphipathic material, Gd (III) [N,N-bis-stearylamidomethyl-N′-amidomethyl] diethylenetriamine tetraacetic acid, into the liposome membrane using lipid film hydration method. GBI-10, as the targeting ligand, was then conjugated onto the liposome surface to get GBI-10-targeted gadolinium-loaded liposomes (GTLs). Both nontargeted gadolinium-loaded liposomes and GTLs displayed good dispersion stability, optimal size, and zeta potential for tumor targeting, as well as favorable imaging properties with enhanced relaxivity compared with a commercial MRI contrast agent (CA), gadopentetate dimeglumine. The use of GBI-10 aptamer in this liposomal system was intended to result in increased accumulation of gadolinium at the periphery of C6 glioma cells, where the targeting extracellular matrix protein tenascin-C is overexpressed. Increased cellular binding of GTLs to C6 cells was confirmed by confocal microscopy, flow cytometry, and MRI, demonstrating the promise of this novel delivery system as a carrier of MRI contrast agent for the diagnosis of tumor. These studies provide a new strategy furthering the development of nanomedicine for both diagnosis and therapy of tumor. PMID:26316749

CV2/CRMP5-antibody-related Paraneoplastic Optic Neuropathy Associated with Small-cell Lung Cancer.

PubMed

Nakajima, Masanori; Uchibori, Ayumi; Ogawa, Yuki; Miyazaki, Tai; Ichikawa, Yaeko; Kaneko, Kimihiko; Takahashi, Toshiyuki; Nakashima, Ichiro; Shiraishi, Hirokazu; Motomura, Masakatsu; Chiba, Atsuro

2018-06-01

A 61-year-old woman who had smoked for 41 years developed subacute dizziness, ataxic gait, opsoclonus, and right visual impairment. She had right optic disc swelling and optic nerve gadolinium enhancement on magnetic resonance imaging. She had small-cell lung cancer (SCLC), with CV2/collapsin response mediator protein (CRMP) 5 and HuD antibodies in her serum and cerebrospinal fluid. She was diagnosed with paraneoplastic optic neuropathy (PON) accompanied by paraneoplastic opsoclonus-ataxia syndrome. Her symptoms improved after removing the SCLC. Classical PON is rare in Japan. We recommend assaying for CV2/CRMP5 antibodies and searching for cancer in elderly patients with subacute painless visual impairment.

A polymeric fastener can easily functionalize liposome surfaces with gadolinium for enhanced magnetic resonance imaging.

PubMed

Smith, Cartney E; Shkumatov, Artem; Withers, Sarah G; Yang, Binxia; Glockner, James F; Misra, Sanjay; Roy, Edward J; Wong, Chun-Ho; Zimmerman, Steven C; Kong, Hyunjoon

2013-11-26

Common methods of loading magnetic resonance imaging (MRI) contrast agents into nanoparticles often suffer from challenges related to particle formation, complex chemical modification/purification steps, and reduced contrast efficiency. This study presents a simple, yet advanced process to address these issues by loading gadolinium, an MRI contrast agent, exclusively on a liposome surface using a polymeric fastener. The fastener, so named for its ability to physically link the two functional components together, consisted of chitosan substituted with diethylenetriaminepentaacetic acid (DTPA) to chelate gadolinium, as well as octadecyl chains to stabilize the modified chitosan on the liposome surface. The assembly strategy, mimicking the mechanisms by which viruses and proteins naturally anchor to a cell, provided greater T1 relaxivity than liposomes loaded with gadolinium in both the interior and outer leaflet. Gadolinium-coated liposomes were ultimately evaluated in vivo using murine ischemia models to highlight the diagnostic capability of the system. Taken together, this process decouples particle assembly and functionalization and, therefore, has considerable potential to enhance imaging quality while alleviating many of the difficulties associated with multifunctional particle fabrication.

Myocardial late gadolinium enhancement in specific cardiomyopathies by cardiovascular magnetic resonance: a preliminary experience.

PubMed

Silva, Caterina; Moon, James C; Elkington, Andrew G; John, Anna S; Mohiaddin, Raad H; Pennell, Dudley J

2007-12-01

Late gadolinium enhancement cardiovascular magnetic resonance (CMR) can visualize myocardial interstitial abnormalities. The aim of this study was to assess whether regions of abnormal myocardium can also be visualized by late enhancement gadolinium CMR in the specific cardiomyopathies. A retrospective review of all referrals for gadolinium CMR with specific cardiomyopathy over 20 months. Nine patients with different specific cardiomyopathies were identified. Late enhancement was demonstrated in all patients, with a mean signal intensity of 390 +/- 220% compared with normal regions. The distribution pattern of late enhancement was unlike the subendocardial late enhancement related to coronary territories found in myocardial infarction. The affected areas included papillary muscles (sarcoid), the mid-myocardium (Anderson-Fabry disease, glycogen storage disease, myocarditis, Becker muscular dystrophy) and the global sub-endocardium (systemic sclerosis, Loeffler's endocarditis, amyloid, Churg-Strauss). Focal myocardial late gadolinium enhancement is found in the specific cardiomyopathies, and the pattern is distinct from that seen in infarction. Further systematic studies are warranted to assess whether the pattern and extent of late enhancement may aid diagnosis and prognostic assessment.

A Polymeric Fastener can Easily Functionalize Liposome Surfaces with Gadolinium for Enhanced Magnetic Resonance Imaging

PubMed Central

Smith, Cartney E.; Shkumatov, Artem; Withers, Sarah G.; Glockner, James F.; Misra, Sanjay; Roy, Edward J.; Wong, Chun-Ho; Zimmerman, Steven C.; Kong, Hyunjoon

2013-01-01

Common methods of loading magnetic resonance imaging (MRI) contrast agents into nanoparticles often suffer from challenges related to particle formation, complex chemical modification/purification steps, and reduced contrast efficiency. This study presents a simple, yet advanced process to address these issues by loading gadolinium, an MRI contrast agent, exclusively on a liposome surface using a polymeric fastener. The fastener, so named for its ability to physically link the two functional components together, consisted of chitosan substituted with diethylenetriaminepentaacetic acid (DTPA) to chelate gadolinium, as well as octadecyl chains to stabilize the modified chitosan on the liposome surface. The assembly strategy, mimicking the mechanisms by which viruses and proteins naturally anchor to a cell, provided greater T1 relaxivity than liposomes loaded with gadolinium in both the interior and outer leaflet. Gadolinium-coated liposomes were ultimately evaluated in vivo using murine ischemia models to highlight the diagnostic capability of the system. Taken together, this process decouples particle assembly and functionalization, and therefore has considerable potential to enhance imaging quality while alleviating many of the difficulties associated with multifunctional particle fabrication. PMID:24083377

Serum protein removal from skim milk with a 3-stage, 3× ceramic Isoflux membrane process at 50°C.

PubMed

Adams, Michael C; Barbano, David M

2013-04-01

Small pore microfiltration (MF) can be used to remove serum proteins (SP) from skim milk. The process's SP removal efficiency directly influences the technology's economic feasibility. Our objective was to quantify the capacity of 0.14μm ceramic Isoflux MF membranes (TAMI, Nyons, France) to remove SP from skim milk. A 3-stage, 3×, feed-and-bleed MF study with diafiltration in the latter 2 stages was conducted at 50°C using Isoflux membranes to determine cumulative SP removal percentages and SP removal rates at each processing stage. The experiment was replicated 3 times starting with 3 separate lots of raw milk. In contrast to 3× MF theoretical cumulative SP removal percentages of 68, 90, and 97% after 1, 2, and 3 stages, respectively, the 3× Isoflux MF process removed only 39.5, 58.4, and 70.2% of SP after 1, 2, and 3 stages, respectively. Previous research has been published that provides the skim milk SP removal capacities of 3-stage, 3× 0.1μm ceramic Membralox (Pall Corp., Cortland, NY) uniform transmembrane pressure (UTP), 0.1μm ceramic Membralox graded permeability (GP), and 0.3μm polymeric polyvinylidene fluoride spiral-wound (PVDF-SW) MF systems (Parker-Hannifin, Process Advanced Filtration Division, Tell City, IN) at 50°C. No difference in cumulative SP removal percentage after 3 stages was detected between the Isoflux and previously published PVDF-SW values (70.3%), but SP removal was lower than published GP (96.5%) and UTP (98.3%) values. To remove 95% of SP from 1,000kg of skim milk in 12h it would take 7, 3, 3, and 7 stages with 6.86, 1.91, 2.82, and 17.98m(2) of membrane surface area for the Isoflux, GP, UTP, and PVDF-SW systems, respectively. The MF systems requiring more stages would produce additional permeate at lower protein concentrations. The ceramic MF systems requiring more surface area would incur higher capital costs. The authors hypothesize that SP removal with the Isoflux membranes was lower than theoretical for the following reasons: a range of membrane pore sizes existed (i.e., some pores were too small to pass SP), the selective layer modification and reverse flow conditions at the membrane outlet combined to reduce the effective membrane surface area, and the geometric shape of the Isoflux flow channels promoted early fouling of the membrane and rejection of SP by the foulant. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Gadolinium-Conjugated Gold Nanoshells for Multimodal Diagnostic Imaging and Photothermal Cancer Therapy

PubMed Central

Coughlin, Andrew J.; Ananta, Jeyarama S.; Deng, Nanfu; Larina, Irina V.; Decuzzi, Paolo

2014-01-01

Multimodal imaging offers the potential to improve diagnosis and enhance the specificity of photothermal cancer therapy. Toward this goal, we have engineered gadolinium-conjugated gold nanoshells and demonstrated that they enhance contrast for magnetic resonance imaging, X-Ray, optical coherence tomography, reflectance confocal microscopy, and two-photon luminescence. Additionally, these particles effectively convert near-infrared light to heat, which can be used to ablate cancer cells. Ultimately, these studies demonstrate the potential of gadolinium-nanoshells for image-guided photothermal ablation. PMID:24115690

Gadolinium Scandium Gallium Garnet (GSGG) as a Solid-State Laser Host

DTIC Science & Technology

1987-07-01

o*SATI CODSi1.SBEC EM (otne nrvrs fnceayad dniy nb)k ubr ~~~~~~~~ Gadolinium Scandium Gallium Garnet (GSGG)asaSldtteLerHt 17. ABSTRACT 6.SUJCTTEM...certain other garnet materials for replacement. It also addresses the solid-state laser host material Gadolinium Scandium Gal- lium Garnet (GSGG) and its...by neodymium-doped yttrium aluminum garnet (Nd:YAG) or other mate- rials for most applications. In the years after the invention of the ruby laser, in

Nitrogen removal and microbial communities in a three-stage system simulating a riparian environment.

PubMed

Wang, Ziyuan; Wang, Zhixin; Pei, Yuansheng

2014-06-01

The riparian zone is an active interface for nitrogen removal, in which nitrogen transformations by microorganisms have not been valued. In this study, a three-stage system was constructed to simulate the riparian zone environments, and nitrogen removal as well as the microbial community was investigated in this 'engineered riparian system'. The results demonstrated that stage 1 of this system accounted for 41-51 % of total nitrogen removal. Initial ammonium loading and redox potential significantly impacted the nitrogen removal performances. Stages 1 and 2 were both composed of an anoxic/oxic (A/O) zone and an anaerobic column. The A/O zone removed most of the ammonium load (6.8 g/m(2)/day), while the anaerobic column showed a significant nitrate removal rate (11.1 g/m(2)/day). Molecular biological analysis demonstrated that bacterial diversity was high in the A/O zones, where ammonium-oxidizing bacteria and nitrite-oxidizing bacteria accounted for 8.42 and 3.32 % of the bacterial population, respectively. The denitrifying bacteria Acidovorax sp. and the nitrifying bacteria Nitrosospira/Nitrosomonas were the predominant microorganisms in this engineered riparian system. This three-stage system was established to achieve favorable nitrogen removal and the microbial community in the system was also retained. This investigation should deepen our understanding of biological nitrogen removal in engineered riparian zones.

In vivo magnetic resonance imaging of atherosclerotic lesions with a newly developed Evans blue-DTPA-gadolinium contrast medium in apolipoprotein-E-deficient mice.

PubMed

Yasuda, Satoshi; Ikuta, Kenjiro; Uwatoku, Toyokazu; Oi, Keiji; Abe, Kohtaro; Hyodo, Fuminori; Yoshimitsu, Kengo; Sugimura, Kohtaro; Utsumi, Hideo; Katayama, Yoshiki; Shimokawa, Hiroaki

2008-01-01

Magnetic resonance imaging (MRI) contrast agents that specifically detect atherosclerotic plaque may be useful for the noninvasive detection of the plaque. We have recently developed a new contrast agent, Evans blue-DTPA-gadolinium (EB-DTPA-Gd), which selectively accumulates vascular lesions with endothelial removal. In this study, we examined whether EB-DTPA-Gd is also useful for in vivo imaging of atherosclerotic plaques. We used male apolipoprotein-E-deficient (ApoE-/-) mice of different ages (3, 6 and 12 months old) and age-matched male wild-type mice. After a single intravenous administration of EB-DTPA-Gd (160 microM/kg body weight), MRI T(1) signal was obtained in vivo. Increased signal intensity in the aortic wall was noted within 10-20 min after intravenous injection of EB-DTPA-Gd and was maintained for 30 min. The MRI enhancement in the aorta of ApoE-/- mice was increased in accordance with age, whereas no such enhancement was noted in wild-type mice. Histological examination demonstrated that there was a topological correlation between the site of MRI enhancement and that of atherosclerotic plaque. These results indicate that EB-DTPA-Gd is a useful MRI contrast medium for the in vivo detection of atherosclerotic plaques. Copyright (c) 2007 S. Karger AG, Basel.

Gadolinium photoionization process

DOEpatents

Paisner, J.A.; Comaskey, B.J.; Haynam, C.A.; Eggert, J.H.

1993-04-13

A method is provided for selective photoionization of the odd-numbered atomic mass gadolinium isotopes 155 and 157. The selective photoionization is accomplished by circular or linear parallel polarized laser beam energy effecting a three-step photoionization pathway.

Gadolinium photoionization process

DOEpatents

Paisner, Jeffrey A.; Comaskey, Brian J.; Haynam, Christopher A.; Eggert, Jon H.

1993-01-01

A method is provided for selective photoionization of the odd-numbered atomic mass gadolinium isotopes 155 and 157. The selective photoionization is accomplished by circular or linear parallel polarized laser beam energy effecting a three-step photoionization pathway.

Kinetic characteristics of the luminescence decay for industrial yttrium-gadolinium-aluminium garnet based phosphors

NASA Astrophysics Data System (ADS)

Lisitsyn, V. M.; Stepanov, S. A.; Valiev, D. T.; Vishnyakova, E. A.; Abdullin, H. A.; Marhabaeva, A. A.; Tulegenova, A. T.

2016-02-01

The spectral and decay kinetic characteristics of pulse cathodoluminescence and photoluminescence of phosphors based on yttrium-gadolinium-aluminum garnet were investigated using pulsed optical time resolved spectroscopy.

Transient arterial phase respiratory motion-related artifact in MR imaging of the liver: an analysis of four different gadolinium-based contrast agents.

PubMed

Shah, Mansi R; Flusberg, Milana; Paroder, Viktoriya; Rozenblit, Alla M; Chernyak, Victoria

The purpose was to compare hepatic arterial phase (HAP) respiratory motion artifact (RMA) between gadoxetate, gadobutrol, gadopentetate, and gadobenate. Two hundred cases of each gadolinium agent were included. RMA was assigned using 5-point Likert scale (1=no motion, 5=extreme motion) on precontrast and HAP. RMA increase (increase ≥1 on HAP from precontrast) was the outcome in logistic regression. Odds of RMA increase for gadoxetate were 5.5 (P<.001), 3.6 (P=.034), and 9.5 (P<.001) times higher than gadobutrol, gadopentetate, and gadobenate, respectively. Gadolinium volume and dose were not independent predictors of RMA increase. Gadoxetate has increased odds of RMA compared with other gadolinium agents; tight contrast bolus is not a contributor. Copyright © 2016 Elsevier Inc. All rights reserved.

The High Radiosensitizing Efficiency of a Trace of Gadolinium-Based Nanoparticles in Tumors

NASA Astrophysics Data System (ADS)

Dufort, Sandrine; Le Duc, Géraldine; Salomé, Murielle; Bentivegna, Valerie; Sancey, Lucie; Bräuer-Krisch, Elke; Requardt, Herwig; Lux, François; Coll, Jean-Luc; Perriat, Pascal; Roux, Stéphane; Tillement, Olivier

2016-07-01

We recently developed the synthesis of ultrasmall gadolinium-based nanoparticles (GBN), (hydrodynamic diameter <5 nm) characterized by a safe behavior after intravenous injection (renal clearance, preferential accumulation in tumors). Owing to the presence of gadolinium ions, GBN can be used as contrast agents for magnetic resonance imaging (MRI) and as radiosensitizers. The attempt to determine the most opportune delay between the intravenous injection of GBN and the irradiation showed that a very low content of radiosensitizing nanoparticles in the tumor area is sufficient (0.1 μg/g of particles, i.e. 15 ppb of gadolinium) for an important increase of the therapeutic effect of irradiation. Such a promising and unexpected result is assigned to a suited distribution of GBN within the tumor, as revealed by the X-ray fluorescence (XRF) maps.

Characterization of the reaction products and precipitates at the interface of carbon fiber reinforced magnesium–gadolinium composite

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

Wang, Yaping; Jiang, Longtao, E-mail: longtaojiang@163.com; Chen, Guoqin

2016-03-15

In the present work, carbon fiber reinforced magnesium-gadolinium composite was fabricated by pressure infiltration method. The phase composition, micro-morphology, and crystal structure of reaction products and precipitates at the interface of the composite were investigated. Scanning electron microscopy and energy dispersive spectroscopy analysis revealed the segregation of gadolinium element at the interface between carbon fiber and matrix alloy. It was shown that block-shaped Gd4C5, GdC2 and nano-sized Gd2O3 were formed at the interface during the fabrication process due to the interfacial reaction. Furthermore, magnesium-gadolinium precipitates including needle-like Mg5Gd (or Mg24Gd5) and thin plate-shaped long period stacking-ordered phase, were also observedmore » at the interface and in the matrix near the interface. The interfacial microstructure and bonding mode were influenced by these interfacial products, which were beneficial for the improvement of the interfacial bonding strength. - Highlights: • Gadolinium element segregated on the surface of carbon fibers. • Block-shaped Gd{sub 4}C{sub 5} and GdC{sub 2} were formed at the interface via chemical reaction. • Gadolinium and oxygen reacted at the interface and formed nano-scaled Gd{sub 2}O{sub 3}. • The precipitates formed in the interface were identified to be Mg{sub 5}Gd (or Mg{sub 24}Gd{sub 5}) and plate-shaped long period stacking-ordered phase.« less

Cardiovascular Magnetic Resonance and prognosis in cardiac amyloidosis

PubMed Central

Maceira, Alicia M; Prasad, Sanjay K; Hawkins, Philip N; Roughton, Michael; Pennell, Dudley J

2008-01-01

Background Cardiac involvement is common in amyloidosis and associated with a variably adverse outcome. We have previously shown that cardiovascular magnetic resonance (CMR) can assess deposition of amyloid protein in the myocardial interstitium. In this study we assessed the prognostic value of late gadolinium enhancement (LGE) and gadolinium kinetics in cardiac amyloidosis in a prospective longitudinal study. Materials and methods The pre-defined study end point was all-cause mortality. We prospectively followed a cohort of 29 patients with proven cardiac amyloidosis. All patients underwent biopsy, 2D-echocardiography and Doppler studies, 123I-SAP scintigraphy, serum NT pro BNP assay, and CMR with a T1 mapping method and late gadolinium enhancement (LGE). Results Patients with were followed for a median of 623 days (IQ range 221, 1436), during which 17 (58%) patients died. The presence of myocardial LGE by itself was not a significant predictor of mortality. However, death was predicted by gadolinium kinetics, with the 2 minute post-gadolinium intramyocardial T1 difference between subepicardium and subendocardium predicting mortality with 85% accuracy at a threshold value of 23 ms (the lower the difference the worse the prognosis). Intramyocardial T1 gradient was a better predictor of survival than FLC response to chemotherapy (Kaplan Meier analysis P = 0.049) or diastolic function (Kaplan-Meier analysis P = 0.205). Conclusion In cardiac amyloidosis, CMR provides unique information relating to risk of mortality based on gadolinium kinetics which reflects the severity of the cardiac amyloid burden. PMID:19032744

Distribution of late gadolinium enhancement in various types of cardiomyopathies: Significance in differential diagnosis, clinical features and prognosis

PubMed Central

Satoh, Hiroshi; Sano, Makoto; Suwa, Kenichiro; Saitoh, Takeji; Nobuhara, Mamoru; Saotome, Masao; Urushida, Tsuyoshi; Katoh, Hideki; Hayashi, Hideharu

2014-01-01

The recent development of cardiac magnetic resonance (CMR) techniques has allowed detailed analyses of cardiac function and tissue characterization with high spatial resolution. We review characteristic CMR features in ischemic and non-ischemic cardiomyopathies (ICM and NICM), especially in terms of the location and distribution of late gadolinium enhancement (LGE). CMR in ICM shows segmental wall motion abnormalities or wall thinning in a particular coronary arterial territory, and the subendocardial or transmural LGE. LGE in NICM generally does not correspond to any particular coronary artery distribution and is located mostly in the mid-wall to subepicardial layer. The analysis of LGE distribution is valuable to differentiate NICM with diffusely impaired systolic function, including dilated cardiomyopathy, end-stage hypertrophic cardiomyopathy (HCM), cardiac sarcoidosis, and myocarditis, and those with diffuse left ventricular (LV) hypertrophy including HCM, cardiac amyloidosis and Anderson-Fabry disease. A transient low signal intensity LGE in regions of severe LV dysfunction is a particular feature of stress cardiomyopathy. In arrhythmogenic right ventricular cardiomyopathy/dysplasia, an enhancement of right ventricular (RV) wall with functional and morphological changes of RV becomes apparent. Finally, the analyses of LGE distribution have potentials to predict cardiac outcomes and response to treatments. PMID:25068019

78 FR 28776 - Approval and Promulgation of Implementation Plans; Kentucky; Stage II Requirements for Enterprise...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-16

... the December 12, 2006, EPA policy memorandum from Stephen D. Page, entitled ``Removal of Stage II... memorandum from Stephen D. Page entitled, ``Removal of Stage II Vapor Recovery in Situations Where Widespread...

Adiabatic Demagnetisation Refrigerators for Future Sub-Millimetre Space Missions

NASA Astrophysics Data System (ADS)

Hepburn, I. D.; Davenport, I.; Smith, A.

1995-10-01

Space worthy refrigeration capable of providing a 100 mK and below heat load sink for bolometric detectors will be required for the next generation of sub-millimetre space missions. Adiabatic demagnetisation refrigeration (ADR), being a gravity independent laboratory method for obtaining such temperatures, is a favourable technique for utilisation in space. We show that by considering a 3 salt pill refrigerator rather than the classic single salt pill design the space prohibitive laboratory ADR properties of high magnetic field (6 Tesla) and a<2 K environment (provided by a bath of liquid4He) can be alleviated, while maintaining a sufficient low temperature hold time and short recycle time. The additional salt pills, composed of Gadolinium Gallium Garnet (GGG) provide intermediate cooling stages, enabling operation from a 4 K environment provided by a single 4 K mechanical cooler, thereby providing consumable free operation. Such ADRs could operate with fields as low as 1 Tesla allowing the use of high temperature, mechanically cooled superconducting magnets and so effectively remove the risk of quenching. We discuss the possibility of increasing the hold time from 3 hours, for the model presented, to between 40 and 80 hours, plus reducing the number of salt pills to two, through the use of a more efficient Garnet. We believe the technical advances necessitated by the envisaged ADRs are minimal and conclude that such ADRs offer a long orbital life time, consumable free, high efficiency means of milli-Kelvin cooling, requiring relatively little laboratory development.

[HIV-associated myelopathy: an uncommon indicator of AIDS].

PubMed

Konaté, A; Ceballos, P; Rivière, S; Faucherre, V; Ciurana, A J; Le Quellec, A

2001-10-01

Spinal cord lesions are an uncommon mode of discovering acquired immunodeficiency syndrome because they usually appear at a later stage. We report a 58-year-old patient who had a spastic paraparesia and sphincter dysfunction. The spinal cord magnetic resonance imaging showed spontaneous hypersignals on T2-weighted images at the cervical and thoracic levels, enhanced with gadolinium, and without swelling. No cause was found. The HIV serology was positive and allowed us to consider an HIV-associated myelopathy. The antiretroviral therapy led to functional recovery. An HIV serology is suggested whenever an unexplained intramedullary lesion is discovered. Indeed, the diagnosis of HIV-associated myelopathy implies a specific therapeutic approach.

Porphyrin-containing polyaspartamide gadolinium complexes as potential magnetic resonance imaging contrast agents.

PubMed

Yan, Guo-Ping; Li, Zhen; Xu, Wei; Zhou, Cheng-Kai; Yang, Lian; Zhang, Qiao; Li, Liang; Liu, Fan; Han, Lin; Ge, Yuan-Xing; Guo, Jun-Fang

2011-04-04

Porphyrin-containing polyaspartamide ligands (APTSPP-PHEA-DTPA) were synthesized by the incorporation of diethylenetriaminepentaacetic acid (DTPA) and 5-(4'-aminophenyl)-10,15,20-tris(4'-sulfonatophenyl) porphyrin, trisodium salt (APTSPP) into poly-α,β-[N-(2-hydroxyethyl)-l-aspartamide] (PHEA). These ligands were further reacted with gadolinium chloride to produce macromolecule-gadolinium complexes (APTSPP-PHEA-DTPA-Gd). Experimental data of (1)H NMR, IR, UV and elemental analysis evidenced the formation of the polyaspartamide ligands and gadolinium complexes. In vitro and in vivo property tests indicated that APTSPP-PHEA-DTPA-Gd possessed noticeably higher relaxation effectiveness, less toxicity to HeLa cells, and significantly higher enhanced signal intensities (SI) of the VX2 carcinoma in rabbits with lower injection dose requirement than that of Gd-DTPA. Moreover, APTSPP-PHEA-DTPA-Gd was found to greatly enhance the contrast of MR images of the VX2 carcinoma, providing prolonged intravascular duration, and distinguished the VX2 carcinoma and normal tissues in rabbits according to MR image signal enhancements. These porphyrin-containing polyaspartamide gadolinium complexes can be used as the candidates of contrast agents for targeted MRI to tumors. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Solid solutions of gadolinium doped zinc oxide nanorods by combined microwave-ultrasonic irradiation assisted crystallization

NASA Astrophysics Data System (ADS)

Kiani, Armin; Dastafkan, Kamran; Obeydavi, Ali; Rahimi, Mohammad

2017-12-01

Nanocrystalline solid solutions consisting of un-doped and gadolinium doped zinc oxide nanorods were fabricated by a modified sol-gel process utilizing combined ultrasonic-microwave irradiations. Polyvinylpyrrolidone, diethylene glycol, and triethylenetetramine respectively as capping, structure directing, and complexing agents were used under ultrasound dynamic aging and microwave heating to obtain crystalline nanorods. Crystalline phase monitoring, lattice parameters and variation, morphology and shape, elemental analysis, functional groups, reducibility, and the oxidation state of emerged species were examined by PXRD, FESEM, TEM, EDX, FTIR, micro Raman, H2-TPR, and EPR techniques. Results have verified that irradiation mechanism of gelation and crystallization reduces the reaction time, augments the crystal quality, and formation of hexagonal close pack structure of Wurtzite morphology. Besides, dissolution of gadolinium within host lattice involves lattice deformation, unit cell distortion, and angular position variation. Structure related shape and growth along with compositional purity were observed through microscopic and spectroscopic surveys. Furthermore, TPR and EPR studies elucidated more detailed behavior upon exposure to the exerted irradiations and subsequent air-annealing including the formed oxidation states and electron trapping centers, presence of gadolinium, zinc, and oxygen disarrays and defects, as well as alteration in the host unit cell via gadolinium addition.

Magnetization reversal and inverted magnetoresistance of exchange-biased spin valves with a gadolinium layer

NASA Astrophysics Data System (ADS)

Milyaev, M.; Naumova, L.; Chernyshova, T.; Proglyado, V.; Kamensky, I.; Krinitsina, T.; Ryabukhina, M.; Ustinov, V.

2017-03-01

FeMn-based spin valves with a gadolinium layer have been fabricated by magnetron sputtering. The magnetoresistive properties of the spin valves have been investigated at temperatures of 80-293 K. Temperature-induced switching between low- and high-resistance magnetic states has been revealed. Realization of the low- or high-resistance states depends on which magnetic moment dominates in the exchange-coupled Gd/CoFe, of Gd or CoFe. It has been shown that the switching temperature depends on the thickness of the gadolinium layer.

MRI of normal and abnormal duodenum using Half-Fourier Single-Shot RARE and gadolinium-enhanced spoiled gradient echo sequences.

PubMed

Marcos, H B; Semelka, R C; Noone, T C; Woosley, J T; Lee, J K

1999-07-01

The objective of this research was two-fold: First, to describe the normal and abnormal MR appearances of the duodenum using combined Half-Fourier Acquisition Single Shot RARE (HASTE) and gadolinium-enhanced standard and fat suppressed spoiled gradient echo (SGE) sequences. The second objective was to assess the ability of these combined sequences to detect and characterize duodenal diseases. MR examinations were performed on fifty consecutive patients with no clinical history of duodenal diseases, who were 1) imaged with HASTE and gadolinium-enhanced standard and fat suppressed SGE sequences and 2) referred to MR examination for reasons other than duodenal diseases, and were reviewed retrospectively to determine the normal MR appearances of the duodenum. A second population of patients with abnormal duodenum who were imaged with the same MR sequences were included in the second part of this study. This population was composed of 20 consecutive patients with subsequently proven duodenal abnormalities, including: malrotation (2), diverticula (4), intussusception (1), sprue (1), polyps (2), neurofibroma (1), lymphoma (1), Zollinger Ellison syndrome (1), metastatic disease (1), Crohn's disease (1), and wall thickening and duodenitis (5). Normal measurements of the duodenum are described. Abnormalities of wall thickness and duodenal masses required combined HASTE and gadolinium-enhanced SGE images to evaluate well. Abnormalities of the bowel lumen (e.g., diverticula and intussusception), and developmental variants (e.g., malrotation), were sufficiently visualized on HASTE images alone. Bowel inflammation was best shown on gadolinium-enhanced fat suppressed SGE images. HASTE and gadolinium-enhanced fat suppressed SGE sequences are complementary techniques for the demonstration of normal and abnormal duodenum. The combined use of both sequences allows evaluation of different aspects of bowel diseases; abnormalities of position, lumen, and contents are well shown on HASTE, while inflammation is best shown on gadolinium enhanced fat suppressed SGE, and wall thickening and masses are best evaluated with the combined use of both techniques.

Application of two-stage biofilter system for the removal of odorous compounds.

PubMed

Jeong, Gwi-Taek; Park, Don-Hee; Lee, Gwang-Yeon; Cha, Jin-Myeong

2006-01-01

Biofiltration is a biological process which is considered to be one of the more successful examples of biotechnological applications to environmental engineering, and is most commonly used in the removal of odoriferous compounds. In this study, we have attempted to assess the efficiency with which both single and complex odoriferous compounds could be removed, using one- or two-stage biofiltration systems. The tested single odor gases, limonene, alpha-pinene, and iso-butyl alcohol, were separately evaluated in the biofilters. Both limonene and alpha-pinene were removed by 90% or more EC (elimination capacity), 364 g/m3/h and 321 g/m3/h, respectively, at an input concentration of 50 ppm and a retention time of 30 s. The iso-butyl alcohol was maintained with an effective removal yield of more than 90% (EC 375 g/m3/h) at an input concentration of 100 ppm. The complex gas removal scheme was applied with a 200 ppm inlet concentration of ethanol, 70 ppm of acetaldehyde, and 70 ppm of toluene with residence time of 45 s in a one- or two-stage biofiltration system. The removal yield of toluene was determined to be lower than that of the other gases in the one-stage biofilter. Otherwise, the complex gases were sufficiently eliminated by the two-stage biofiltration system.

Measurement of gamma-ray production from thermal neutron capture on gadolinium for neutrino experiments

NASA Astrophysics Data System (ADS)

Yano, Takatomi; 2012B0025 Collaboration; 2014B0126 Collaboration

2017-02-01

Recently, several scientific applications of gadolinium are found in neutrino physics experiments. Gadolinium-157 is the nucleus, which has the largest thermal neutron capture cross-section among all stable nuclei. Gadolinium-155 also has the large cross-section. These neutron capture reactions provide the gamma-ray cascade with the total energy of about 8 MeV. This reaction is applied for several neutrino experiments, e.g. reactor neutrino experiments and Gd doped large water Cherenkov detector experiments, to recognize inverse-beta-decay reaction. A good Gd(n,γ) simulation model is needed to evaluate the detection efficiency of the neutron capture reaction, i.e. the efficiency of IBD detection. In this presentation, we will report the development and study status of a Gd(n,γ) calculation model and comparison with our experimental data taken at ANNRI/MLF beam line, J-PARC.

A comparison of the COG and MCNP codes in computational neutron capture therapy modeling, Part II: gadolinium neutron capture therapy models and therapeutic effects.

PubMed

Wangerin, K; Culbertson, C N; Jevremovic, T

2005-08-01

The goal of this study was to evaluate the COG Monte Carlo radiation transport code, developed and tested by Lawrence Livermore National Laboratory, for gadolinium neutron capture therapy (GdNCT) related modeling. The validity of COG NCT model has been established for this model, and here the calculation was extended to analyze the effect of various gadolinium concentrations on dose distribution and cell-kill effect of the GdNCT modality and to determine the optimum therapeutic conditions for treating brain cancers. The computational results were compared with the widely used MCNP code. The differences between the COG and MCNP predictions were generally small and suggest that the COG code can be applied to similar research problems in NCT. Results for this study also showed that a concentration of 100 ppm gadolinium in the tumor was most beneficial when using an epithermal neutron beam.

Nephrogenic systemic fibrosis (NSF): a late adverse reaction to some of the gadolinium based contrast agents

PubMed Central

Marckmann, Peter; Logager, Vibeke B.

2007-01-01

Abstract Until recently it was believed that extracellular gadolinium based contrast agents were safe for both the kidneys and all other organs within the dose range up to 0.3 mmol/kg body weight. However, in 2006, it was demonstrated that some gadolinium based contrast agents may trigger the development of nephrogenic systemic fibrosis, a generalised fibrotic disorder, in renal failure patients. Accordingly, the use of gadodiamide and gadopentate dimeglumine for renal failure patients was banned in Europe in spring 2007. The same two compounds should only be used cautiously in patients with moderate renal dysfunction. The current paper reviews the situation (July 2007) regarding gadolinium based contrast agent and the severe delayed reaction to some of these agents. The fear of nephrogenic systemic fibrosis should not lead to a denial of a well indicated enhanced magnetic resonance imaging examination. PMID:17905680

Gadolinium-enhanced computed tomographic angiography: current status.

PubMed

Rosioreanu, Alex; Alberico, Ronald A; Litwin, Alan; Hon, Man; Grossman, Zachary D; Katz, Douglas S

2005-01-01

This article reviews the research to date, as well as our clinical experience from two institutions, on gadolinium-enhanced computed tomographic angiography (gCTA) for imaging the body. gCTA may be an appropriate examination for the small percentage of patients who would benefit from noninvasive vascular imaging, but who have contraindications to both iodinated contrast and magnetic resonance imaging. gCTA is more expensive than CTA with iodinated contrast, due to the dose of gadolinium administered, and gCTA has limitations compared with CTA with iodinated contrast, in that parenchymal organs are not optimally enhanced at doses of 0.5 mmol/kg or lower. However, in our experience, gCTA has been a very useful problem-solving examination in carefully selected patients. With the advent of 16-64 detector CT, in combination with bolus tracking, we believe that the overall dose of gadolinium needed for diagnostic CTA examinations, while relatively high, can be safely administered.

Room temperature ferromagnetic gadolinium silicide nanoparticles

DOEpatents

Hadimani, Magundappa Ravi L.; Gupta, Shalabh; Harstad, Shane; Pecharsky, Vitalij; Jiles, David C.

2018-03-06

A particle usable as T₁ and T₂ contrast agents is provided. The particle is a gadolinium silicide (Gd₅Si₄) particle that is ferromagnetic at temperatures up to 290 K and is less than 2 .mu.m in diameter. An MRI contrast agent that includes a plurality of gadolinium silicide (Gd.sub.5Si.sub.4) particles that are less than 1 .mu.m in diameter is also provided. A method for creating gadolinium silicide (Gd₅Si₄) particles is also provided. The method includes the steps of providing a Gd₅Si₄ bulk alloy; grinding the Gd₅Si₄ bulk alloy into a powder; and milling the Gd₅Si₄ bulk alloy powder for a time of approximately 20 minutes or less.

Biocompatible blood pool MRI contrast agents based on hyaluronan

PubMed Central

Zhu, Wenlian; Artemov, Dmitri

2010-01-01

Biocompatible gadolinium blood pool contrast agents based on a biopolymer, hyaluronan, were investigated for magnetic resonance angiography application. Hyaluronan, a non-sulfated linear glucosaminoglycan composed of 2000–25,000 repeating disaccharide subunits of D-glucuronic acid and N-acetylglucosamine with molecular weight up to 20 MDa, is a major component of the extracellular matrix. Two gadolinium contrast agents based on 16 and 74 kDa hyaluronan were synthesized, both with R1 relaxivity around 5 mM−1 s−1 per gadolinium at 9.4 T at 25°C. These two hyaluronan based agents show significant enhancement of the vasculature for an extended period of time. Initial excretion was primarily through the renal system. Later uptake was observed in the stomach and lower gastrointestinal tract. Macromolecular hyaluronan-based gadolinium agents have a high clinical translation potential as hyaluronan is already approved by FDA for a variety of medical applications. PMID:21504061

The network formers role of gadolinium(III) ions in some zinc-borate glass ceramics

NASA Astrophysics Data System (ADS)

Bosca, Maria; Pop, Lidia; Pascuta, Petru

2017-12-01

EPR and magnetic susceptibility measurements were performed on glass ceramics from the (Gd2O3)x.(B2O3)(60-x).(ZnO)40 system, with 0 ≤ x ≤ 15 mol%, in order to determine the role of gadolinium ions on structural and magnetic properties. At low Gd2O3 contents (x ≤ 1 mol%) the EPR spectra show four resonance lines with effective g-values of ˜ 6, 4.8, 2.8 and 2, typical for Gd3+ ions uniformly distributed in the glass and glass ceramic samples. For higher contents of gadolinium ions (x ≥ 3 mol%) the EPR spectra are dominated by a single broad line centered at g ˜ 2, which can be due to the magnetic clusters containing Gd3+ ions. The magnetic susceptibility data show that the gadolinium ions are involved in superexchange interactions in all the investigated glass ceramics, being antiferromagnetically coupled.

Method and apparatus for removing coarse unentrained char particles from the second stage of a two-stage coal gasifier

DOEpatents

Donath, Ernest E.

1976-01-01

A method and apparatus for removing oversized, unentrained char particles from a two-stage coal gasification process so as to prevent clogging or plugging of the communicating passage between the two gasification stages. In the first stage of the process, recycled process char passes upwardly while reacting with steam and oxygen to yield a first stage synthesis gas containing hydrogen and oxides of carbon. In the second stage, the synthesis gas passes upwardly with coal and steam which react to yield partially gasified char entrained in a second stage product gas containing methane, hydrogen, and oxides of carbon. Agglomerated char particles, which result from caking coal particles in the second stage and are too heavy to be entrained in the second stage product gas, are removed through an outlet in the bottom of the second stage, the particles being separated from smaller char particles by a counter-current of steam injected into the outlet.

Use of a 3-Telsa magnet to perform delayed gadolinium-enhanced magnetic resonance imaging of the distal interphalangeal joint of horses with and without naturally occurring osteoarthritis.

PubMed

Bischofberger, Andrea S; Fürst, Anton E; Torgerson, Paul R; Carstens, Ann; Hilbe, Monika; Kircher, Patrick

2018-03-01

OBJECTIVE To characterize delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) features of healthy hyaline cartilage of the distal interphalangeal joint (DIPJ) of horses, to determine whether dGEMRIC can be used to differentiate various stages of naturally occurring osteoarthritis of the DIPJ, and to correlate relaxation times determined by dGEMRIC with the glycosaminoglycan concentration, water content, and macroscopic and histologic findings of hyaline cartilage of DIPJs with and without osteoarthritis. SAMPLE 1 cadaveric forelimb DIPJ from each of 12 adult warmblood horses. PROCEDURES T1-weighted cartilage relaxation times were obtained for predetermined sites of the DIPJ before (T1 preGd ) and after (T1 postGd ) intra-articular gadolinium administration. Corresponding cartilage sites underwent macroscopic, histologic, and immunohistochemical evaluation, and cartilage glycosaminoglycan concentration and water content were determined. Median T1 preGd and T1 postGd were correlated with macroscopic, histologic, and biochemical data. Mixed generalized linear models were created to evaluate the effects of cartilage site, articular surface, and macroscopic and histologic scores on relaxation times. RESULTS 122 cartilage specimens were analyzed. Median T1 postGd was lower than the median T1 preGd for normal and diseased cartilage. Both T1 preGd and T1 postGd were correlated with macroscopic and histologic scores, whereby T1 preGd increased and T1 postGd decreased as osteoarthritis progressed. There was topographic variation of T1 preGd and T1 postGd within the DIPJ. Cartilage glycosaminoglycan concentration and water content were significantly correlated with T1 preGd and macroscopic and histologic scores but were not correlated with T1 postGd . CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dGEMRIC relaxation times varied for DIPJs with various degrees of osteoarthritis. These findings may help facilitate early detection of osteoarthritis.

Magnetic resonance imaging (MRI) of the renal sinus.

PubMed

Krishna, Satheesh; Schieda, Nicola; Flood, Trevor A; Shanbhogue, Alampady Krishna; Ramanathan, Subramaniyan; Siegelman, Evan

2018-04-09

This article presents methods to improve MR imaging approach of disorders of the renal sinus which are relatively uncommon and can be technically challenging. Multi-planar Single-shot T2-weighted (T2W) Fast Spin-Echo sequences are recommended to optimally assess anatomic relations of disease. Multi-planar 3D-T1W Gradient Recalled Echo imaging before and after Gadolinium administration depicts the presence and type of enhancement and relation to arterial, venous, and collecting system structures. To improve urographic phase MRI, concentrated Gadolinium in the collecting systems should be diluted. Diffusion-Weighted Imaging (DWI) should be performed before Gadolinium administration to minimize T2* effects. Renal sinus cysts are common but can occasionally be confused for dilated collecting system or calyceal diverticula, with the latter communicating with the collecting system and filling on urographic phase imaging. Vascular lesions (e.g., aneurysm, fistulas) may mimic cystic (or solid) lesions on non-enhanced MRI but can be suspected by noting similar signal intensity to the blood pool and diagnosis can be confirmed with MR angiogram/venogram. Multilocular cystic nephroma commonly extends to the renal sinus, however, to date are indistinguishable from cystic renal cell carcinoma (RCC). Solid hilar tumors are most commonly RCC and urothelial cell carcinoma (UCC). Hilar RCC are heterogeneous, hypervascular with epicenter in the renal cortex compared to UCC which are centered in the collecting system, homogeneously hypovascular, and show profound restricted diffusion. Diagnosis of renal sinus invasion in RCC is critically important as it is the most common imaging cause of pre-operative under-staging of disease. Fat is a normal component of the renal sinus; however, amount of sinus fat correlates with cardiovascular disease and is also seen in lipomatosis. Fat-containing hilar lesions include lipomas, angiomyolipomas, and less commonly other tumors which engulf sinus fat. Mesenchymal hilar tumors are rare. MR imaging diagnosis is generally not possible, although anatomic relations should be described to guide diagnosis by percutaneous biopsy or surgery.

Treatment of Ammonia Nitrogen Wastewater in Low Concentration by Two-Stage Ozonization.

PubMed

Luo, Xianping; Yan, Qun; Wang, Chunying; Luo, Caigui; Zhou, Nana; Jian, Chensheng

2015-09-23

Ammonia nitrogen wastewater (about 100 mg/L) was treated by two-stage ozone oxidation method. The effects of ozone flow rate and initial pH on ammonia removal were studied, and the mechanism of ammonia nitrogen removal by ozone oxidation was discussed. After the primary stage of ozone oxidation, the ammonia removal efficiency reached 59.32% and pH decreased to 6.63 under conditions of 1 L/min ozone flow rate and initial pH 11. Then, the removal efficiency could be over 85% (the left ammonia concentration was lower than 15 mg/L) after the second stage, which means the wastewater could have met the national discharge standards of China. Besides, the mechanism of ammonia removal by ozone oxidation was proposed by detecting the products of the oxidation: ozone oxidation directly and ·OH oxidation; ammonia was mainly transformed into NO₃(-)-N, less into NO₂(-)-N, not into N₂.

Design and monitoring of horizontal subsurface-flow constructed wetlands for treating nursery leachates.

PubMed

Narváez, Lola; Cunill, Conrad; Cáceres, Rafaela; Marfà, Oriol

2011-06-01

Nursery leachates usually contain high concentrations of nitrates, phosphorus and potassium, so discharging them into the environment often causes pollution. Single-stage or two-stage horizontal subsurface flow constructed wetlands (HSSCW) filled with different substrates were designed to evaluate the effect and evolution over time of the removal of nitrogen and other nutrients contained in nursery leachates. The addition of sodium acetate to achieve a C:NO(3)(-)-N ratio of 3:1 was sufficient to reach complete denitrification in all HSSCW. The removal rate of nitrate was high throughout the operation period (over 98%). Nevertheless, the removal rate of ammonium decreased about halfway through the operation. Removal of the COD was enhanced by the use of two-stage HSSCW. In general, the substrates and the number of stages of the wetlands did not affect the removal of nitrogen, total phosphorus and potassium. Copyright © 2011 Elsevier Ltd. All rights reserved.

Improved paramagnetic chelate for molecular imaging with MRI

NASA Astrophysics Data System (ADS)

Winter, Patrick; Athey, Phillip; Kiefer, Garry; Gulyas, Gyongyi; Frank, Keith; Fuhrhop, Ralph; Robertson, David; Wickline, Samuel; Lanza, Gregory

2005-05-01

The relaxivity and transmetallation of two lipophilic paramagnetic chelates incorporated onto perfluorocarbon nanoparticles, i.e., gadolinium-methoxy-tetraazacyclododecane-tetraacetic acid phosphatidylethanolamine (Gd-MeO-DOTA-PE) and gadolinium-methoxy-tetraazacyclododecane-tetraacetic acid triglycine phosphatidylethanolamine (Gd-MeO-DOTA-triglycine-PE (Gd-MeO-DOTA-triglycine-PE)), were compared to a prototypic gadolinium-diethylene-triamine-pentaacetic acid bis-oleate (Gd-DTPA-BOA) paramagnetic formulation. Nanoparticles with MeO-DOTA-based chelates demonstrated higher relaxivity (40% higher for Gd-MeO-DOTA-PE and 55% higher for Gd-MeO-DOTA-triglycine-PE) and less transmetallation than the original Gd-DTPA-BOA-based agent.

Recovery of methamphetamine associated cardiomyopathy predicted by late gadolinium enhanced cardiovascular magnetic resonance.

PubMed

Lopez, Javier E; Yeo, Khung; Caputo, Gary; Buonocore, Michael; Schaefer, Saul

2009-11-11

Methamphetamine is known to cause a cardiomyopathy which may be reversible with appropriate medical therapy and cessation of use. Late gadolinium enhancement cardiovascular magnetic resonance (CMR) has been shown to identify fibrosis in ischemic and non-ischemic cardiomyopathies. We present a case of severe methamphetamine-associated cardiomyopathy in which cardiac function recovered after 6 months. Evaluation by CMR using late gadolinium enhancement was notable for an absence of enhancement, suggesting an absence of irreversible myocyte injury and a good prognosis. CMR may be useful to predict recovery in toxin-associated non-ischemic cardiomyopathies.

Recovery of methamphetamine associated cardiomyopathy predicted by late gadolinium enhanced cardiovascular magnetic resonance

PubMed Central

2009-01-01

Methamphetamine is known to cause a cardiomyopathy which may be reversible with appropriate medical therapy and cessation of use. Late gadolinium enhancement cardiovascular magnetic resonance (CMR) has been shown to identify fibrosis in ischemic and non-ischemic cardiomyopathies. We present a case of severe methamphetamine-associated cardiomyopathy in which cardiac function recovered after 6 months. Evaluation by CMR using late gadolinium enhancement was notable for an absence of enhancement, suggesting an absence of irreversible myocyte injury and a good prognosis. CMR may be useful to predict recovery in toxin-associated non-ischemic cardiomyopathies. PMID:19906310

Do we need gadolinium-based contrast medium for brain magnetic resonance imaging in children?

PubMed

Dünger, Dennis; Krause, Matthias; Gräfe, Daniel; Merkenschlager, Andreas; Roth, Christian; Sorge, Ina

2018-06-01

Brain imaging is the most common examination in pediatric magnetic resonance imaging (MRI), often combined with the use of a gadolinium-based contrast medium. The application of gadolinium-based contrast medium poses some risk. There is limited evidence of the benefits of contrast medium in pediatric brain imaging. To assess the diagnostic gain of contrast-enhanced sequences in brain MRI when the unenhanced sequences are normal. We retrospectively assessed 6,683 brain MR examinations using contrast medium in children younger than 16 years in the pediatric radiology department of the University Hospital Leipzig to determine whether contrast-enhanced sequences delivered additional, clinically relevant information to pre-contrast sequences. All examinations were executed using a 1.5-T or a 3-T system. In 8 of 3,003 (95% confidence interval 0.12-0.52%) unenhanced normal brain examinations, a relevant additional finding was detected when contrast medium was administered. Contrast enhancement led to a change in diagnosis in only one of these cases. Children with a normal pre-contrast brain MRI rarely benefit from contrast medium application. Comparing these results to the risks and disadvantages of a routine gadolinium application, there is substantiated numerical evidence for avoiding routine administration of gadolinium in a pre-contrast normal MRI examination.

Accumulation of MRI contrast agents in malignant fibrous histiocytoma for gadolinium neutron capture therapy.

PubMed

Fujimoto, T; Ichikawa, H; Akisue, T; Fujita, I; Kishimoto, K; Hara, H; Imabori, M; Kawamitsu, H; Sharma, P; Brown, S C; Moudgil, B M; Fujii, M; Yamamoto, T; Kurosaka, M; Fukumori, Y

2009-07-01

Neutron-capture therapy with gadolinium (Gd-NCT) has therapeutic potential, especially that gadolinium is generally used as a contrast medium in magnetic resonance imaging (MRI). The accumulation of gadolinium in a human sarcoma cell line, malignant fibrosis histiocytoma (MFH) Nara-H, was visualized by the MRI system. The commercially available MRI contrast medium Gd-DTPA (Magnevist, dimeglumine gadopentetate aqueous solution) and the biodegradable and highly gadopentetic acid (Gd-DTPA)-loaded chitosan nanoparticles (Gd-nanoCPs) were prepared as MRI contrast agents. The MFH cells were cultured and collected into three falcon tubes that were set into the 3-tesra MRI system to acquire signal intensities from each pellet by the spin echo method, and the longitudinal relaxation time (T1) was calculated. The amount of Gd in the sample was measured by inductively coupled plasma atomic emission spectrography (ICP-AES). The accumulation of gadolinium in cells treated with Gd-nanoCPs was larger than that in cells treated with Gd-DTPA. In contrast, and compared with the control, Gd-DTPA was more effective than Gd-nanoCPs in reducing T1, suggesting that the larger accumulation exerted the adverse effect of lowering the enhancement of MRI. Further studies are warranted to gain insight into the therapeutic potential of Gd-NCT.

In vitro radiosensitizing effects of ultrasmall gadolinium based particles on tumour cells.

PubMed

Mowat, P; Mignot, A; Rima, W; Lux, F; Tillement, O; Roulin, C; Dutreix, M; Bechet, D; Huger, S; Humbert, L; Barberi-Heyob, M; Aloy, M T; Armandy, E; Rodriguez-Lafrasse, C; Le Duc, G; Roux, S; Perriat, P

2011-09-01

Since radiotherapy is widely used in cancer treatment, it is essential to develop strategies which lower the irradiation burden while increasing efficacy and become efficient even in radio resistant tumors. Our new strategy is relying on the development of solid hybrid nanoparticles based on rare-earth such as gadolinium. In this paper, we then evidenced that gadolinium-based particles can be designed to enter efficiently into the human glioblastoma cell line U87 in quantities that can be tuned by modifying the incubation conditions. These sub-5 nm particles consist in a core of gadolinium oxide, a shell of polysiloxane and are functionalized by diethylenetriaminepentaacetic acid (DTPA). Although photoelectric effect is maximal in the [10-100 keV] range, such particles were found to possess efficient in-vitro radiosensitizing properties at an energy of 660 keV by using the "single-cell gel electrophoresis comet assay," an assay that measures the number of DNA damage that occurs during irradiation. Even more interesting, the particles have been evidenced by MTT assays to be also efficient radiosensitizers at an energy of 6 MeV for doses comprised between 2 and 8 Gy. The properties of the gadolinium-based particles give promising opening to a particle-assisted radio-therapy by using irradiation systems already installed in the majority of hospitals.

Removal of pharmaceuticals in pre-denitrifying MBBR - Influence of organic substrate availability in single- and three-stage configurations.

PubMed

Polesel, Fabio; Torresi, Elena; Loreggian, Luca; Casas, Mònica Escolà; Christensson, Magnus; Bester, Kai; Plósz, Benedek Gy

2017-10-15

Due to the limited efficiency of conventional biological treatment, innovative solutions are being explored to improve the removal of trace organic chemicals in wastewater. Controlling biomass exposure to growth substrate represents an appealing option for process optimization, as substrate availability likely impacts microbial activity, hence organic trace chemical removal. This study investigated the elimination of pharmaceuticals in pre-denitrifying moving bed biofilm reactors (MBBRs), where biofilm exposure to different organic substrate loading and composition was controlled by reactor staging. A three-stage MBBR and a single-stage reference MBBR (with the same operating volume and filling ratio) were operated under continuous-flow conditions (18 months). Two sets of batch experiments (day 100 and 471) were performed to quantify and compare pharmaceutical removal and denitrification kinetics in the different MBBRs. Experimental results revealed the possible influence of retransformation (e.g., from conjugated metabolites) and enantioselectivity on the removal of selected pharmaceuticals. In the second set of experiments, specific trends in denitrification and biotransformation kinetics were observed, with highest and lowest rates/rate constants in the first (S1) and the last (S3) staged sub-reactors, respectively. These observations were confirmed by removal efficiency data obtained during continuous-flow operation, with limited removal (<10%) of recalcitrant pharmaceuticals and highest removal in S1 within the three-stage MBBR. Notably, biotransformation rate constants obtained for non-recalcitrant pharmaceuticals correlated with mean specific denitrification rates, maximum specific growth rates and observed growth yield values. Overall, these findings suggest that: (i) the long-term exposure to tiered substrate accessibility in the three-stage configuration shaped the denitrification and biotransformation capacity of biofilms, with significant reduction under substrate limitation; (ii) biotransformation of pharmaceuticals may have occurred as a result of cometabolism by heterotrophic denitrifying bacteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Steam and air co-injection in removing TCE in 2D-sand box].

PubMed

Wang, Ning; Peng, Sheng; Chen, Jia-Jun

2014-07-01

Steam and air co-injection is a newly developed and promising soil remediation technique for non-aqueous phase liquids (NAPLs) in vadose zone. In this study, in order to investigate the mechanism of the remediation process, trichloroethylene (TCE) removal using steam and air co-injection was carried out in a 2-dimensional sandbox with different layered sand structures. The results showed that co-injection perfectly improved the "tailing" effect compared to soil vapor extraction (SVE), and the remediation process of steam and air co-injection could be divided into SVE stage, steam strengthening stage and heat penetration stage. Removal ratio of the experiment with scattered contaminant area was higher and removal speed was faster. The removal ratios from the two experiments were 93.5% and 88.2%, and the removal periods were 83.9 min and 90.6 min, respectively. Steam strengthened the heat penetration stage. The temperature transition region was wider in the scattered NAPLs distribution experiment, which reduced the accumulation of TCE. Slight downward movement of TCE was observed in the experiment with TCE initially distributed in a fine sand zone. And such downward movement of TCE reduced the TCE removal ratio.

Usefulness of the advanced neuroimaging protocol based on plain and gadolinium-enhanced constructive interference in steady state images for gamma knife radiosurgery and planning microsurgical procedures for skull base tumors.

PubMed

Hayashi, Motohiro; Chernov, Mikhail F; Tamura, Noriko; Yomo, Shoji; Tamura, Manabu; Horiba, Ayako; Izawa, Masahiro; Muragaki, Yoshihiro; Iseki, Hiroshi; Okada, Yoshikazu; Ivanov, Pavel; Régis, Jean; Takakura, Kintomo

2013-01-01

Gamma Knife radiosurgery (GKS) is currently performed with 0.1 mm preciseness, which can be designated microradiosurgery. It requires advanced methods for visualizing the target, which can be effectively attained by a neuroimaging protocol based on plain and gadolinium-enhanced constructive interference in steady state (CISS) images. Since 2003, the following thin-sliced images are routinely obtained before GKS of skull base lesions in our practice: axial CISS, gadolinium-enhanced axial CISS, gadolinium-enhanced axial modified time-of-flight (TOF), and axial computed tomography (CT). Fusion of "bone window" CT and magnetic resonance imaging (MRI), and detailed three-dimensional (3D) delineation of the anatomical structures are performed with the Leksell GammaPlan (Elekta Instruments AB). Recently, a similar technique has been also applied to evaluate neuroanatomy before open microsurgical procedures. Plain CISS images permit clear visualization of the cranial nerves in the subarachnoid space. Gadolinium-enhanced CISS images make the tumor "lucid" but do not affect the signal intensity of the cranial nerves, so they can be clearly delineated in the vicinity to the lesion. Gadolinium-enhanced TOF images are useful for 3D evaluation of the interrelations between the neoplasm and adjacent vessels. Fusion of "bone window" CT and MRI scans permits simultaneous assessment of both soft tissue and bone structures and allows 3D estimation and correction of MRI distortion artifacts. Detailed understanding of the neuroanatomy based on application of the advanced neuroimaging protocol permits performance of highly conformal and selective radiosurgical treatment. It also allows precise planning of the microsurgical procedures for skull base tumors.

Multiple Removal of Spent Rocket Upper Stages with an Ion Beam Shepherd

NASA Astrophysics Data System (ADS)

Bombardelli, C.; Herrera-Montojo, J.; Gonzalo, J. L.

2013-08-01

Among the many advantages of the recently proposed ion beam shepherd (IBS) debris removal technique is the capability to deal with multiple targets in a single mission. A preliminary analysis is here conducted in order to estimate the cost in terms of spacecraft mass and total mission time to remove multiple large-size upper stages of the Zenit family. Zenit-2 upper stages are clustered at 71 degrees inclination around 850 km altitude in low Earth orbit. It is found that a removal of two targets per year is feasible with a modest size spacecraft. The most favorable combinations of targets are outlined.

Development of a low-cost biogas filtration system to achieve higher-power efficient AC generator

NASA Astrophysics Data System (ADS)

Mojica, Edison E.; Ardaniel, Ar-Ar S.; Leguid, Jeanlou G.; Loyola, Andrea T.

2018-02-01

The paper focuses on the development of a low-cost biogas filtration system for alternating current generator to achieve higher efficiency in terms of power production. A raw biogas energy comprises of 57% combustible element and 43% non-combustible elements containing carbon dioxide (36%), water vapor (5%), hydrogen sulfide (0.5%), nitrogen (1%), oxygen (0 - 2%), and ammonia (0 - 1%). The filtration system composes of six stages: stage 1 is the water scrubber filter intended to remove the carbon dioxide and traces of hydrogen sulfide; stage 2 is the silica gel filter intended to reduce the water vapor; stage 3 is the iron sponge filter intended to remove the remaining hydrogen sulfide; stage 4 is the sodium hydroxide solution filter intended to remove the elemental sulfur formed during the interaction of the hydrogen sulfide and the iron sponge and for further removal of carbon dioxide; stage 5 is the silica gel filter intended to further eliminate the water vapor gained in stage 4; and, stage 6 is the activated carbon filter intended to remove the carbon dioxide. The filtration system was able to lower the non-combustible elements by 72% and thus, increasing the combustible element by 54.38%. The unfiltered biogas is capable of generating 16.3 kW while the filtered biogas is capable of generating 18.6 kW. The increased in methane concentration resulted to 14.11% increase in the power output. The outcome resulted to better engine performance in the generation of electricity.

Type-II domains in ferroelectric gadolinium molybdate (in German)

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

Bohm, J.; Kuersten, H.D.

Etching (001)-faces of gadolinium molybdate (GMO) reveals new kinds of domains. They are created by a translation, that leaves the spontaneous polarization and the transition parameter invariant. The translation vector is a part of a lattice vector, similar to stacking faults. (auth)

[Rapid imaging in orbito-ocular pathology. Contribution of gadolinium].

PubMed

Pigeau, I; Legeais, J M; D'Hermies, F; Fayet, B; Leport, M; Abenhaim, A; Guinet, C; Levy, C; Renard, G; Vadrot, D

1990-01-01

To evaluate Gradient-Echo Imaging (GEI) in orbito-ocular pathology, 15 volunteers and 34 patients (40 lesions) were examined with GEA T1 and GEA T2 (0.5 T). Results were compared with SE T1 in all cases, with SE T2 in 20 cases and with other imaging modalities (CT). 30 patients were examined before and after injection of gadolinium. Final diagnosis was obtained by surgery or biopsy in 24 cases or by combined results of imaging and clinical findings in 16 cases. Compared with SE, GEA demonstrated a better visualisation of optic nerve, orbital muscles, choroidal-retinal layer, lens capsule and episclera and a better detection of small lesions. It is very helpful for characterisation of lesions containing hemorrhages or paramagnetic components (melanine, gadolinium) or of vascular nature (angioma). Gadolinium was useful for detection of small lesions or characterisation of a few lesions. Thus GEA seems to be an efficient method for the evaluation of orbito-ocular pathology.

Skin manifestations of chronic kidney disease.

PubMed

Robles-Mendez, J C; Vazquez-Martinez, O; Ocampo-Candiani, J

2015-10-01

Skin manifestations associated with chronic kidney disease are very common. Most of these conditions present in the end stages and may affect the patient's quality of life. Knowledge of these entities can contribute to establishing an accurate diagnosis and prognosis. Severe renal pruritus is associated with increased mortality and a poor prognosis. Nail exploration can provide clues about albumin and urea levels. Nephrogenic systemic fibrosis is a preventable disease associated with gadolinium contrast. Comorbidities, such as diabetes mellitus and secondary hyperparathyroidism, can lead to acquired perforating dermatosis and calciphylaxis, respectively. Effective and innovative treatments are available for all of these conditions. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.

[Unclassified cardiomyopathy or Lyme carditis? A three year follow-up].

PubMed

Konopka, Marcin; Kuch, Marek; Braksator, Wojciech; Walczak, Ewa; Jakuciński, Maciej; Lipowski, Dariusz; Dłużniewski, Mirosław

2013-01-01

Lyme carditis can be a clinical manifestation of the early disseminated stage of Lyme disease caused by the tick-transmitted pathogen Borrelia burgdorferi. We present the case of a 41 year-old Caucasian woman referred to our hospital with symptoms of fatigue, progressive exertional dyspnoea, supraventricular cardiac arrhythmia, and an enlarged heart revealed on chest radiography. Following an untypical result of transthoracic echocardiography, cardiac magnetic resonance was performed. This showed structural cardiac changes and focus of late gadolinium enhancement in the midwall of the apex region. Further diagnostic processes, including endomyocardial biopsy and serology tests, made it possible to diagnose Lyme carditis. Clinical observation was followed-up for three years.

The effect of viewing angle on the spectral behavior of a Gd plasma source near 6.7 nm

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

O'Gorman, Colm; Li Bowen; Cummins, Thomas

2012-04-02

We have demonstrated the effect of viewing angle on the extreme ultraviolet (EUV) emission spectra of gadolinium (Gd) near 6.7 nm. The spectra are shown to have a strong dependence on viewing angle when produced with a laser pulse duration of 10 ns, which may be attributed to absorption by low ion stages of Gd and an angular variation in the ion distribution. Absorption effects are less pronounced at a 150-ps pulse duration due to reduced opacity resulting from plasma expansion. Thus for evaluating source intensity, it is necessary to allow for variation with both viewing angle and target orientation.

78 FR 58184 - Approval and Promulgation of Implementation Plans; North Carolina; Removal of Stage II Gasoline...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-23

...] Approval and Promulgation of Implementation Plans; North Carolina; Removal of Stage II Gasoline Vapor... measures for new and upgraded gasoline dispensing facilities in the State. The September 18, 2009, SIP... .0953), entitled Vapor Return Piping for Stage II Vapor Recovery, for all new or improved gasoline tanks...

Treatment of Ammonia Nitrogen Wastewater in Low Concentration by Two-Stage Ozonization

PubMed Central

Luo, Xianping; Yan, Qun; Wang, Chunying; Luo, Caigui; Zhou, Nana; Jian, Chensheng

2015-01-01

Ammonia nitrogen wastewater (about 100 mg/L) was treated by two-stage ozone oxidation method. The effects of ozone flow rate and initial pH on ammonia removal were studied, and the mechanism of ammonia nitrogen removal by ozone oxidation was discussed. After the primary stage of ozone oxidation, the ammonia removal efficiency reached 59.32% and pH decreased to 6.63 under conditions of 1 L/min ozone flow rate and initial pH 11. Then, the removal efficiency could be over 85% (the left ammonia concentration was lower than 15 mg/L) after the second stage, which means the wastewater could have met the national discharge standards of China. Besides, the mechanism of ammonia removal by ozone oxidation was proposed by detecting the products of the oxidation: ozone oxidation directly and ·OH oxidation; ammonia was mainly transformed into NO3−-N, less into NO2−-N, not into N2. PMID:26404353

Removal of pharmaceuticals and organic matter from municipal wastewater using two-stage anaerobic fluidized membrane bioreactor.

PubMed

Dutta, Kasturi; Lee, Ming-Yi; Lai, Webber Wei-Po; Lee, Chien Hsien; Lin, Angela Yu-Chen; Lin, Cheng-Fang; Lin, Jih-Gaw

2014-08-01

The aim of present study was to treat municipal wastewater in two-stage anaerobic fluidized membrane bioreactor (AFMBR) (anaerobic fluidized bed reactor (AFBR) followed by AFMBR) using granular activated carbon (GAC) as carrier medium in both stages. Approximately 95% COD removal efficiency could be obtained when the two-stage AFMBR was operated at total HRT of 5h (2h for AFBR and 3h for AFMBR) and influent COD concentration of 250mg/L. About 67% COD and 99% TSS removal efficiency could be achieved by the system treating the effluent from primary clarifier of municipal wastewater treatment plant, at HRT of 1.28h and OLR of 5.65kg COD/m(3)d. The system could also effectively remove twenty detected pharmaceuticals in raw wastewaters with removal efficiency in the range of 86-100% except for diclofenac (78%). No other membrane fouling control was required except scouring effect of GAC for flux of 16LMH. Copyright © 2014 Elsevier Ltd. All rights reserved.

A two-stage pretreatment process using dilute hydrochloric acid followed by Fenton oxidation to improve sugar recovery from corn stover.

PubMed

Li, Wenzhi; Liu, Qiyu; Ma, Qiaozhi; Zhang, Tingwei; Ma, Longlong; Jameel, Hasan; Chang, Hou-Min

2016-11-01

A two-stage pretreatment process is proposed in this research in order to improve sugar recovery from corn stover. In the proposed process, corn stover is hydrolyzed by dilute hydrochloric acid to recover xylose, which is followed by a Fenton reagent oxidation to remove lignin. 0.7wt% dilute hydrochloric acid is applied in the first stage pretreatment at 120°C for 40min, resulting in 81.0% xylose removal. Fenton reagent oxidation (1g/L FeSO4·7H2O and 30g/L H2O2) is performed at room temperature (about 20°C) for 12 has a second stage which resulted in 32.9% lignin removal. The glucose yield in the subsequent enzymatic hydrolysis was 71.3% with a very low cellulase dosage (3FPU/g). This two-stage pretreatment is effective due to the hydrolysis of hemicelluloses in the first stage and the removal of lignin in the second stage, resulting in a very high sugar recovery with a low enzyme loading. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gadolinium chelate coated gold nanoparticles as contrast agents for both X-ray computed tomography and magnetic resonance imaging.

PubMed

Alric, Christophe; Taleb, Jacqueline; Le Duc, Géraldine; Mandon, Céline; Billotey, Claire; Le Meur-Herland, Alice; Brochard, Thierry; Vocanson, Francis; Janier, Marc; Perriat, Pascal; Roux, Stéphane; Tillement, Olivier

2008-05-07

Functionalized gold nanoparticles were applied as contrast agents for both in vivo X-ray and magnetic resonance imaging. These particles were obtained by encapsulating gold cores within a multilayered organic shell which is composed of gadolinium chelates bound to each other through disulfide bonds. The contrast enhancement in MRI stems from the presence of gadolinium ions which are entrapped in the organic shell, whereas the gold core provides a strong X-ray absorption. This study revealed that these particles suited for dual modality imaging freely circulate in the blood vessels without undesirable accumulation in the lungs, spleen, and liver.

Poly(acrylic acid) Bridged Gadolinium Metal-Organic Framework-Gold Nanoparticle Composites as Contrast Agents for Computed Tomography and Magnetic Resonance Bimodal Imaging.

PubMed

Tian, Chixia; Zhu, Liping; Lin, Feng; Boyes, Stephen G

2015-08-19

Imaging contrast agents for magnetic resonance imaging (MRI) and computed tomography (CT) have received significant attention in the development of techniques for early stage cancer diagnosis. Gadolinium (Gd)(III), which has seven unpaired electrons and a large magnetic moment, can dramatically influence the water proton relaxation and hence exhibits excellent MRI contrast. On the other hand, gold (Au), which has a high atomic number and high X-ray attenuation coefficient, is an ideal contrast agent candidate for X-ray-based CT imaging. Gd metal-organic framework (MOF) nanoparticles with tunable size, high Gd(III) loading and multivalency can potentially overcome the limitations of clinically utilized Gd chelate contrast agents. In this work, we report for the first time the integration of GdMOF nanoparticles with gold nanoparticles (AuNPs) for the preparation of a MRI/CT bimodal imaging agent. Highly stable hybrid GdMOF/AuNPs composites have been prepared by using poly(acrylic acid) as a bridge between the GdMOF nanoparticles and AuNPs. The hybrid nanocomposites were then evaluated in MRI and CT imaging. The results revealed high longitudinal relaxivity in MRI and excellent CT imaging performance. Therefore, these GdMOF/AuNPs hybrid nanocomposites potentially provide a new platform for the development of multimodal imaging probes.

Poly(acrylic acid) Bridged Gadolinium Metal-Organic Framework-Gold Nanoparticle Composites as Contrast Agents for Computed Tomography and Magnetic Resonance Bimodal Imaging

PubMed Central

Tian, Chixia; Zhu, Liping; Lin, Feng; Boyes, Stephen G.

2015-01-01

Imaging contrast agents for magnetic resonance imaging (MRI) and computed tomography (CT) have received significant attention in the development of techniques for early-stage cancer diagnosis. Gadolinium (Gd) (III), which has seven unpaired electrons and a large magnetic moment, can dramatically influence the water proton relaxation and hence exhibits excellent MRI contrast. On the other hand, gold (Au), which has a high atomic number and high x-ray attenuation coefficient, is an ideal contrast agent candidate for x-ray based CT imaging. Gd metal organic framework (MOF) nanoparticles with tunable size, high Gd (III) loading and multivalency can potentially overcome the limitations of clinically utilized Gd chelate contrast agents. In this work, we report for the first time the integration of GdMOF nanoparticles with gold nanoparticles (AuNPs) for the preparation of a MRI/CT bimodal imaging agent. Highly stable hybrid GdMOF/AuNPs composites have been prepared by using poly(acrylic acid) as a bridge between the GdMOF nanoparticles and AuNPs. The hybrid nanocomposites were then evaluated in MRI and CT imaging. The results revealed high longitudinal relaxivity in MRI and excellent CT imaging performance. Therefore, these GdMOF/AuNPs hybrid nanocomposites potentially provide a new platform for the development of multi-modal imaging probes. PMID:26147906

Dual photon absorptiometry using a gadolinium-153 source applied to measure equine bone mineral content

NASA Astrophysics Data System (ADS)

Moure, Alessandro; Reichmann, Peter; Remigio Gamba, Humberto

2003-12-01

The application of the dual photon absorptiometry (DPA) technique, using gadolinium-153 as the photon source, to evaluate the bone mineral density (BMD) of the third metacarpal bone of horses is presented. The radiation detector was implemented with a NaI(TI) scintillator coupled to a 14 stage photomultiplier. A modular mechanical system allows the position of the prototype to be adjusted in relation to the animal. A moveable carrier makes it possible to scan the third metacarpal with a velocity adjustable between 1 and 12 mm s-1, in steps of 1 mm s-1, for a total distance of 250 mm. The prototype was evaluated with a phantom of the third metacarpal bone made of perspex and aluminium, and in vitro with a transverse slice of the third metacarpal bone of a horse. The tests showed that the prototype has an accuracy and precision of, approximately, 10% and 6%, respectively, for a 6 s acquisition time. Preliminary studies carried out in three foals from birth to one year of age indicated that the prototype is well suited to in vivo and in situ analysis of the BMD of the third metacarpal bones of horses, making it possible to evaluate the changes of BMD levels on a monthly basis. Also, results indicated an exponential behaviour of the BMD curve during the first year of life of the studied horses.

Gadolinium-Loaded Solid Lipid Nanoparticles as a Tumor-Absorbable Contrast Agent for Early Diagnosis of Colorectal Tumors Using Magnetic Resonance Colonography.

PubMed

Sun, Jihong; Zhang, Shizheng; Jiang, Shaojie; Bai, Weixian; Liu, Fei; Yuan, Hong; Ji, Jiansong; Luo, Jingfeng; Han, Guocan; Chen, Lumin; Jin, Yin; Hu, Peng; Yu, Lei; Yang, Xiaoming

2016-09-01

Magnetic resonance (MR) contrast agents focusing on special functions are required to improve cancer diagnosis, particularly in the early stages. Here, we designed multifunctional solid lipid nanoparticles (SLNs) with simultaneous loading of gadolinium (Gd) diethylenetriaminepentaacetic acid (Gd-DTPA) and octadecylamine fluorescein isothiocyanate (FITC) to obtain Gd-FITC-SLNs as a tumor-absorbable nanoparticle contrast agent for the histological confirmation of MR imaging (MRI) findings. Colorectal tumors were evaluated in vitro and in vivo via direct uptake of this contrast agent, which displayed reasonable T1 relaxivity and no significant cytotoxicity at the experimental concentrations in human colon carcinoma cells (HT29) and mouse colon carcinoma cells (CT26). In vitro cell uptake experiments demonstrated that contrast agent absorption by the two types of cancer cells was concentration-dependent in the safe concentration range. During in vivo MRI, transrectal infusion of Gd-FITC-SLNs showed more significant enhancement at the tumor site compared with the infusion of Gd-DTPA in female C57/BL mice with azoxymethane/dextran sulfate sodium-induced colorectal highgrade intraepithelial neoplasia. Subsequent confocal fluorescence microscopy demonstrated Gd-FITC-SLNs as highly concentrated green fluorescent spots distributed from the tumor capsule into the tumor. This study establishes the "proof-of-principle" of a new MRI technique wherein colorectal tumors are enhanced via direct absorption or uptake of the nanoparticle contrast agent.

High-Sensitivity High-Speed X-ray Fluorescence Scanning Cadmium Telluride Detector for Deep-Portion Cancer Diagnosis Utilizing Tungsten-Kα-Excited Gadolinium Mapping

NASA Astrophysics Data System (ADS)

Yanbe, Yutaka; Sato, Eiichi; Chiba, Hiraku; Maeda, Tomoko; Matsushita, Ryo; Oda, Yasuyuki; Hagiwara, Osahiko; Matsukiyo, Hiroshi; Osawa, Akihiro; Enomoto, Toshiyuki; Watanabe, Manabu; Kusachi, Shinya; Sato, Shigehiro; Ogawa, Akira

2013-09-01

X-ray fluorescence (XRF) analysis is useful for mapping various atoms in objects. Bremsstrahlung X-rays with energies beyond tantalum (Ta) K-edge energy 67.4 keV are absorbed effectively using a 100-µm-thick Ta filter, and the filtered X-rays including tungsten (W) Kα rays are absorbed by gadolinium (Gd) atoms in objects. The Gd XRF is then produced from Gd atoms in the objects and is counted by a cadmium telluride (CdTe) detector. Gd Kα photons with a maximum count rate of 1 kilo counts per second are dispersed using a multichannel analyzer, and the number of photons is counted by a counter card. The distance between the CdTe detector and the object is minimized to 40 mm to increase the count rate. The object is scanned using an x-y stage with a velocity of 5.0 mm/s, and Gd mapping are shown on a computer monitor. The scan steps of the x- and y-axes were both 2.5 mm, and the photon-counting time per mapping point was 0.5 s. We obtained Gd XRF images at high contrast, and Gd Kα photons were easily detected from cancerous regions in a nude mouse placed behind a 20-mm-thick poly(methyl methacrylate) plate.

Bi-atrial fibrosis detected using three-dimensional late gadolinium enhancement magnetic resonance imaging in a patient with cardiac sarcoidosis.

PubMed

Spence, Stewart; Pena, Elena; Thornhill, Rebecca E; Nery, Pablo B; Birnie, David H

2018-05-01

Presented is the case of a 62-year old male with a history of sarcoidosis and sinus node dysfunction, who underwent late gadolinium enhancement magnetic resonance imaging, which demonstrated left ventricular hyperenhancement and bi-atrial fibrosis.

Influence of the implant-abutment connection design and diameter on the screw joint stability.

PubMed

Shin, Hyon-Mo; Huh, Jung-Bo; Yun, Mi-Jeong; Jeon, Young-Chan; Chang, Brian Myung; Jeong, Chang-Mo

2014-04-01

This study was conducted to evaluate the influence of the implant-abutment connection design and diameter on the screw joint stability. Regular and wide-diameter implant systems with three different joint connection designs: an external butt joint, a one-stage internal cone, and a two-stage internal cone were divided into seven groups (n=5, in each group). The initial removal torque values of the abutment screw were measured with a digital torque gauge. The postload removal torque values were measured after 100,000 cycles of a 150 N and a 10 Hz cyclic load had been applied. Subsequently, the rates of the initial and postload removal torque losses were calculated to evaluate the effect of the joint connection design and diameter on the screw joint stability. Each group was compared using Kruskal-Wallis test and Mann-Whitney U test as post-hoc test (α=0.05). THE POSTLOAD REMOVAL TORQUE VALUE WAS HIGH IN THE FOLLOWING ORDER WITH REGARD TO MAGNITUDE: two-stage internal cone, one-stage internal cone, and external butt joint systems. In the regular-diameter group, the external butt joint and one-stage internal cone systems showed lower postload removal torque loss rates than the two-stage internal cone system. In the wide-diameter group, the external butt joint system showed a lower loss rate than the one-stage internal cone and two-stage internal cone systems. In the two-stage internal cone system, the wide-diameter group showed a significantly lower loss rate than the regular-diameter group (P<.05). The results of this study showed that the external butt joint was more advantageous than the internal cone in terms of the postload removal torque loss. For the difference in the implant diameter, a wide diameter was more advantageous in terms of the torque loss rate.

Influence of the implant-abutment connection design and diameter on the screw joint stability

PubMed Central

Shin, Hyon-Mo; Huh, Jung-Bo; Yun, Mi-Jeong; Jeon, Young-Chan; Chang, Brian Myung

2014-01-01

PURPOSE This study was conducted to evaluate the influence of the implant-abutment connection design and diameter on the screw joint stability. MATERIALS AND METHODS Regular and wide-diameter implant systems with three different joint connection designs: an external butt joint, a one-stage internal cone, and a two-stage internal cone were divided into seven groups (n=5, in each group). The initial removal torque values of the abutment screw were measured with a digital torque gauge. The postload removal torque values were measured after 100,000 cycles of a 150 N and a 10 Hz cyclic load had been applied. Subsequently, the rates of the initial and postload removal torque losses were calculated to evaluate the effect of the joint connection design and diameter on the screw joint stability. Each group was compared using Kruskal-Wallis test and Mann-Whitney U test as post-hoc test (α=0.05). RESULTS The postload removal torque value was high in the following order with regard to magnitude: two-stage internal cone, one-stage internal cone, and external butt joint systems. In the regular-diameter group, the external butt joint and one-stage internal cone systems showed lower postload removal torque loss rates than the two-stage internal cone system. In the wide-diameter group, the external butt joint system showed a lower loss rate than the one-stage internal cone and two-stage internal cone systems. In the two-stage internal cone system, the wide-diameter group showed a significantly lower loss rate than the regular-diameter group (P<.05). CONCLUSION The results of this study showed that the external butt joint was more advantageous than the internal cone in terms of the postload removal torque loss. For the difference in the implant diameter, a wide diameter was more advantageous in terms of the torque loss rate. PMID:24843398

Technical Basis for Peak Reactivity Burnup Credit for BWR Spent Nuclear Fuel in Storage and Transportation Systems

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

Marshall, William BJ J; Ade, Brian J; Bowman, Stephen M

2015-01-01

Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission have initiated a multiyear project to investigate application of burnup credit for boiling-water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase (1) investigates applicability of peak reactivity methods currently used in spent fuel pools (SFPs) to storage and transportation systems and (2) evaluates validation of both reactivity (k eff) calculations and burnup credit nuclide concentrations within these methods. The second phase will focus on extending burnup credit beyond peak reactivity. This paper documents the first phase, including an analysis of latticemore » design parameters and depletion effects, as well as both validation components. Initial efforts related to extended burnup credit are discussed in a companion paper. Peak reactivity analyses have been used in criticality analyses for licensing of BWR fuel in SFPs over the last 20 years. These analyses typically combine credit for the gadolinium burnable absorber present in the fuel with a modest amount of burnup credit. Gadolinium burnable absorbers are used in BWR assemblies to control core reactivity. The burnable absorber significantly reduces assembly reactivity at beginning of life, potentially leading to significant increases in assembly reactivity for burnups less than 15–20 GWd/MTU. The reactivity of each fuel lattice is dependent on gadolinium loading. The number of gadolinium-bearing fuel pins lowers initial lattice reactivity, but it has a small impact on the burnup and reactivity of the peak. The gadolinium concentration in each pin has a small impact on initial lattice reactivity but a significant effect on the reactivity of the peak and the burnup at which the peak occurs. The importance of the lattice parameters and depletion conditions are primarily determined by their impact on the gadolinium depletion. Criticality code validation for BWR burnup credit at peak reactivity requires a different set of experiments than for pressurized-water reactor burnup credit analysis because of differences in actinide compositions, presence of residual gadolinium absorber, and lower fission product concentrations. A survey of available critical experiments is presented along with a sample criticality code validation and determination of undercoverage penalties for some nuclides. The validation of depleted fuel compositions at peak reactivity presents many challenges which largely result from a lack of radiochemical assay data applicable to BWR fuel in this burnup range. In addition, none of the existing low burnup measurement data include residual gadolinium measurements. An example bias and uncertainty associated with validation of actinide-only fuel compositions is presented.« less

Nephrogenic systemic fibrosis is associated with hypophosphataemia: a case-control study.

PubMed

Bernstein, Elana J; Isakova, Tamara; Sullivan, Mary E; Chibnik, Lori B; Wolf, Myles; Kay, Jonathan

2014-09-01

Nephrogenic systemic fibrosis (NSF) is an iatrogenic fibrosing disorder that primarily affects individuals with chronic kidney disease (CKD) following exposure to gadolinium-based contrast agents (GBCAs). Derangements of calcium and phosphorus have been reported in patients with NSF. The aim of this study was to investigate potential factors in addition to GBCA exposure that may be involved in the pathogenesis of NSF. We hypothesized that patients with stage 5 CKD and NSF would manifest greater alterations in calcium, phosphorus and fibroblast growth factor 23 (FGF23) levels than those who do not have NSF. Levels of phosphorus, calcium, FGF23 and 25-hydroxy-vitamin D were measured in 10 patients with stage 5 CKD and biopsy-proven NSF and in 19 patients with stage 5 CKD without NSF. Statistical analyses were performed using Fisher's exact test for categorical variables and the Kruskal-Wallis test for continuous variables. Patients with NSF had significantly lower phosphorus levels compared with controls (P = 0.01). There were no significant differences between NSF patients and controls in calcium, 25-hydroxy-vitamin D, intact parathyroid hormone or FGF23 levels. Differences in phosphorus metabolism may exist between patients with stage 5 CKD and NSF compared with patients with stage 5 CKD without NSF. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Loeffler endocarditis as a rare cause of heart failure with preserved ejection fraction: A case report and review of literature.

PubMed

Gao, Ming; Zhang, Weihua; Zhao, Waiou; Qin, Ling; Pei, Fei; Zheng, Yang

2018-03-01

Hypereosinophilic syndrome (HES) is a rare disease characterized by hypereosinophilia and its ensuing organ damage. Cardiac involvement is divided into 3 chronological stages: an acute necrotic stage; a thrombus formation stage; and a fibrotic stage. Infiltration of the myocardium by eosinophilic cells followed by endomyocardial fibrosis is known as "Loeffler endocarditis." We report a case of a 60-year-old man diagnosed with left-sided restrictive cardiomyopathy. The patient experienced heart failure with preserved ejection fraction. The cardiac MRI showed intense, linear, delayed gadolinium enhancement of the endocardium of the lateral wall of the left ventricle, and obliteration of the LV apex. He was ultimately identified as Loeffler endocarditis. A bone marrow smear and biopsy revealed the FIP1L1-PDGFRA fusion gene was positive in 82% of segmented nucleated cells. Our patient responded well to prednisone at 1 mg/kg/d. HES is a rare disease that often afflicts the heart. Cardiac involvement in hypereosinophilia, especially Loeffler endocarditis, carries a poor prognosis and significant mortality. Early detection and treatment of the disease is therefore essential. Further studies are needed to ascertain therapeutic corticosteroid dosages and develop targeted gene therapies, both important steps to ameliorate the effects of Loeffler endocarditis and improve patient outcomes.

Gadolinium: Central Metal of the Lanthanoids

ERIC Educational Resources Information Center

Laing, Michael

2009-01-01

The physical and chemical properties of gadolinium are compared with those of the other lanthanoids. Some properties are intermediate between those of lanthanum and lutetium; some between those of barium and hafnium; and others (unexpectedly) between those of ytterbium and lutetium. Both the remarkably high molar heat capacity of the metal and the…

Revisiting the Pharmacokinetic Profiles of Gadolinium-Based Contrast Agents: Differences in Long-Term Biodistribution and Excretion.

PubMed

Lancelot, Eric

2016-11-01

Gadolinium-based contrast agents (GBCAs) have been used for years for magnetic resonance imaging examinations. Because of their rapid blood clearance, they were considered as very safe products until some of them were shown to induce nephrogenic systemic fibrosis in patients with renal failure and hypersignals on T1-weighted unenhanced brain scans of patients with normal renal function. To date, these adverse effects have been related almost exclusively to the use of low-stability linear agents, which are more prone to release free gadolinium. The aim of the present meta-analysis was to ascertain the existence of a deep compartment for gadolinium storage in the body and to assess whether all the GBCAs present the same toxicokinetic profile. Applying a systematic literature search methodology, all clinical and preclinical studies reporting time-dependent plasma concentrations and renal excretion data of gadolinium were identified and analyzed. Since the individual data were not available, the analysis focused on the average values per groups of subjects or animals, which had received a given GBCA at a given dose. The rate constants of the distribution phase (α), rapid elimination phase (β), and residual excretion phase (γ) of gadolinium were determined in each group from the plasma concentration (Cp) time curves and the relative urinary excretion rate (rER) time curves, taking the 2-hour time point as a reference. Moreover, as bone may represent a reservoir for long-term gadolinium accumulation and slow release into the blood stream, the time curves of the relative concentration in the bone (rCB) of Gd-labeled GBCAs in mice or rats were analyzed taking day 1 concentrations as a reference. The ratio of gadolinium concentrations in the bone marrow (CBM) as compared with the bone (CB) was also calculated. The relative urinary excretion rate (rER) plots revealed a prolonged residual excretion phase of gadolinium in healthy volunteers, consistent with the existence of a deep compartment of distribution for the GBCAs. The rate constant γ of gadoterate meglumine (0.107 hour) is 5 times higher than that of the linear agents (0.020 ± 0.008 hour), indicating a much faster blood clearance for the macrocyclic GBCA. Similar results were obtained in the preclinical studies. A strong correlation was shown between the γ values of the different products and their respective thermodynamic stability constants (Ktherm). Greater clearance rates of Gd from murine bone were also found after gadoterate meglumine or gadoteridol injection (0.131-0.184 day) than after administration of the linear agents (0.004-0.067 day). The concentrations of Gd in the bone marrow (CBM) from animals exposed to either gadoterate meglumine or gadodiamide are higher than those in the bone (CB) for at least 24 hours. Moreover, the ratio of concentrations (CBM/CB) at 4 hours is significantly lower with the former agent than the latter (1.9 vs 6.5, respectively). Using a nonconventional pharmacokinetic approach, we showed that gadoterate meglumine undergoes a much faster residual excretion from the body than the linear GBCAs, a process that seems related to the thermodynamic stability of the different chelates. Gadolinium dissociation occurs in vivo for some linear chelates, a mechanism that may explain their long-term retention and slow release from bone. Potential consequences in terms of bone toxicity warrant further investigations.

Floodplain restoration enhances denitrification and reach-scale nitrogen removal in an agricultural stream.

PubMed

Roley, Sarah S; Tank, Jennifer L; Stephen, Mia L; Johnson, Laura T; Beaulieu, Jake J; Witter, Jonathan D

2012-01-01

Streams of the agricultural Midwest, USA, export large quantities of nitrogen, which impairs downstream water quality, most notably in the Gulf of Mexico. The two-stage ditch is a novel restoration practice, in which floodplains are constructed alongside channelized ditches. During high flows, water flows across the floodplains, increasing benthic surface area and stream water residence time, as well as the potential for nitrogen removal via denitrification. To determine two-stage ditch nitrogen removal efficacy, we measured denitrification rates in the channel and on the floodplains of a two-stage ditch in north-central Indiana for one year before and two years after restoration. We found that instream rates were similar before and after the restoration, and they were influenced by surface water NO3- concentration and sediment organic matter content. Denitrification rates were lower on the constructed floodplains and were predicted by soil exchangeable NO3- concentration. Using storm flow simulations, we found that two-stage ditch restoration contributed significantly to NO3- removal during storm events, but because of the high NO3- loads at our study site, < 10% of the NO3- load was removed under all storm flow scenarios. The highest percentage of NO3- removal occurred at the lowest loads; therefore, the two-stage ditch's effectiveness at reducing downstream N loading will be maximized when the practice is coupled with efforts to reduce N inputs from adjacent fields.

Investigation on the removal of H2S from microwave pyrolysis of sewage sludge by an integrated two-stage system.

PubMed

Zhang, Jun; Tian, Yu; Yin, Linlin; Zuo, Wei; Gong, Zhenlong; Zhang, Jie

2017-08-01

In this study, an integrated two-stage system, including the in-situ catalytic microwave pyrolysis (ICMP) and subsequent catalytic wet oxidation (CWO) processes, was proposed to remove H 2 S released from microwave-induced pyrolysis of sewage sludge. The emission profile and H 2 S removal from the pyrolysis of raw sewage sludge (SS) and sewage sludge spiked with conditioner CaO (SS-CaO) were investigated. The results showed that CaO played a positive role on sulfur fixation during the pyrolysis process. It was found that SS-CaO (10 wt.%) contributed to about 35% of H 2 S removal at the first stage (ICMP process). Additionally, the CWO process was demonstrated to have promising potential for posttreatment of remaining H 2 S gas. At the Fe 3+ concentration of 30 g/L, the maximum H 2 S removal efficiency of 94.8% was obtained for a single Fe 3+ /Cu 2+ solution. Finally, at the pyrolysis temperature of 800 °C, 99.7% of H 2 S was eliminated by the integrated two-stage system meeting the discharge standard of China. Therefore, the integrated two-stage system of ICMP + CWO may provide a promising strategy to remove H 2 S dramatically for the biomass pyrolysis industry.

Toxicological and pharmacological effects of gadolinium and samarium chlorides

PubMed Central

Haley, T. J.; Raymond, K.; Komesu, N.; Upham, H. C.

1961-01-01

A study has been made of the toxicology and pharmacology of gadolinium and samarium chlorides. The symptoms of acute toxicity following intraperitoneal injection are described. The chronic oral ingestion of both chemicals for 12 weeks produced no effects on growth or the blood picture, and only the male rats receiving gadolinium chloride showed liver damage. The pharmacological responses to both chemicals were mainly depressant on all systems studied, and death was associated with cardiovascular collapse coupled with respiratory paralysis. The greatest damage seen was on abraded skin, where non-healing ulcers were produced by both chemicals, whereas irritation of intact skin and ocular tissues was only transient in nature. PMID:13903826

Development of a Low-Power CO2 Removal and Compression System for Closed-Loop Air Revitalization in Future Spacecraft

NASA Technical Reports Server (NTRS)

Mulloth, Lila M.; Rosen, Micha; Affleck, David; LeVan, M. Douglas; Moate, Joe R.

2005-01-01

The current CO2 removal technology of NASA is very energy intensive and contains many non-optimized subsystems. This paper discusses the design and prototype development of a two-stage CO2 removal and compression system that will utilize much less power than NASA s current CO2 removal technology. This integrated system contains a Nafion membrane followed by a residual water adsorber that performs the function of the desiccant beds in the four-bed molecular sieve (4BMS) system of the International Space Station (ISS). The membrane and the water adsorber are followed by a two-stage CO2 removal and compression subsystem that satisfies the operations of the CO2 adsorbent beds of the 4BMS aid the interface compressor for the Sabatier reactor connection. The two-stage compressor will utilize the principles of temperature-swing adsorption (TSA) compression technology for CO2 removal and compression. The similarities in operation and cycle times of the CO2 removal (first stage) and compression (second stage) operations will allow thermal coupling of the processes to maximize the efficiency of the system. In addition to the low-power advantage, this processor will maintain a lower CO2 concentration in the cabin than that can be achieved by the existing CO2 removal systems. The compact, consolidated, configuration of membrane gas dryer and CO2 separator and compressor will allow continuous recycling of humid air in the cabin and supply of compressed CO2 to the reduction unit for oxygen recovery. The device has potential application to the International Space Station and future, long duration, transit, and planetary missions.

Preparation of 152Gd targets from a small quantity of gadolinium oxide in a pyrochemical reaction

NASA Astrophysics Data System (ADS)

Lipski, A. R.

1995-02-01

A simple method utilizing small amounts (< 5 mg) of isotopically enriched material for the production of gadolinium targets is discussed. An electrostatically focused e-gun is used in the procedure in which 152Gd 2O 3 powder undergoes reduction-distillation and deposition onto an Fe foil.

Two-stage magnetic refrigerator for astronomical applications with reservoir temperatures above 4 K

NASA Astrophysics Data System (ADS)

Hagmann, C.; Richards, P. L.

We propose a novel adiabatic demagnetization refrigerator (ADR) to produce temperatures as low as 100 mK starting from a high temperature reservoir between 4 and 8 K. The high temperature reservoir for the ADR can be provided by a mechanical cooler or an unpumped liquid helium bath. This refrigerator can be used to cool bolometric infrared detectors for low background astronomy from mountain tops, balloons or satellites, as well as to cool cryogenic X-ray detectors. The two-stage ADR consists of a single magnet with a paramagnetic chromic caesium alum (CCA) salt pill to produce the low temperature and paramagnetic gadolinium gallium garnet (GGG) as the first stage to intercept heat from the high temperature reservoir. Thermal contact between the paramagnets and the reservoir during magnetization is made with a mechanical heat switch. The ADR is suspended with Kevlar cords under tension for high mechanical stiffness and low parasitic heat leak. In a single cycle, the ADR maintains a temperature of 100 mK for 10-100 h. This time depends strongly on the magnetic field and reservoir temperature but not on the volume of the paramagnetic material as long as the heat leak is dominated by the suspension.

Characteristics of Gadolinium Oxide Nanoparticles Using Terahertz Spectroscopy (abstract)

NASA Astrophysics Data System (ADS)

Lee, Dongkyu; Maeng, Inhee; Oh, Seung Jae; Kim, Taekhoon; Cho, Byung Kyu; Lee, Kwangyeol; Son, Joo-Hiuk

2009-04-01

The penetration property of the terahertz electromagnetic (THz) wave is relevant to its use. We used the THz wave spectroscopy system which easily penetrates some materials that do not contain water, e.g., plastic and ceramics. The system has been developed for several purposes, including measuring the properties of semiconductors and bio-materials, and detecting plastic bombs and ceramic knives at airports. It is also used for medical imaging systems, such as magnetic resonance imaging (MRI), at some research institutes. It can show not only the difference in amplitude, but also the difference of the phase of each point of sample. MRI technology usually uses contrast agents to enhance the quality of the image. Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), made with a heavy metal ion, is commonly used as a clinical MRI contrast agent. Gadolinium oxide (Gd2O3) nanoparticle is a new contrast agent. It serves to equip the core of each particle with antibodies or ligands. It can freely circulate in blood vessels without amassing in the liver or lungs. This study shows the characteristics of gadolinium oxide nanoparticles to further advance terahertz medical imaging.

Measurement of gadolinium retention: current status and review from an applied radiation physics perspective.

PubMed

Gräfe, James L; McNeill, Fiona E

2018-06-28

This article briefly reviews the main measurement techniques for the non-invasive detection of residual gadolinium (Gd) in those exposed to gadolinium-based contrast agents (GBCAs). Approach and Main results: The current status of in vivo Gd measurement is discussed and is put into the context of concerns within the radiology community. The main techniques are based on applied atomic/nuclear medicine utilizing the characteristic atomic and nuclear spectroscopic signature of Gd. The main emission energies are in the 40-200 keV region and require spectroscopic detectors with good energy resolution. The two main techniques, prompt gamma neutron activation analysis and x-ray fluorescence, provide adequate detection limits for in vivo measurement, whilst delivering a low effective radiation dose on the order of a few µSv. Gadolinium is being detected in measureable quantities in people with healthy renal function who have received FDA approved GBCAs. The applied atomic/nuclear medicine techniques discussed in this review will be useful in determining the significance of this retention, and will help on advising future administration protocols.

K3 Li3 Gd7 (BO3 )9 : A New Gadolinium-Rich Orthoborate for Cryogenic Magnetic Cooling.

PubMed

Xia, Mingjun; Shen, Shipeng; Lu, Jun; Sun, Young; Li, Rukang

2018-03-02

Magnetic cooling technology based on magnetocaloric effect (MCE) has attracted great interest in obtaining extremely low temperatures, for example, for space exploration. Here, we grew a new gadolinium-rich orthoborate K 3 Li 3 Gd 7 (BO 3 ) 9 (1) as a promising cryogenic magnetic coolant. It exhibits a complicated three dimensional framework constructed from BO 3 groups and gadolinium-oxygen chains. The Gd-O chain consists of two types of clusters of Gd 3 O 20 and Gd 3 O 19 interconnection by Gd(4)O 8 polyhydron. Due to its high gadolinium concentration, a large -ΔS m of 56.6 J kg -1  K -1 for 1 was obtained at 2 K and ΔH=7 T, much larger than that of the commercial benchmark Gd 3 Ga 5 O 12 (GGG) crystal (38.4 J kg -1  K -1 ), suggesting it to be an excellent MCE material. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

METHOD FOR REMOVAL OF LIGHT ISOTOPE PRODUCT FROM LIQUID THERMAL DIFFUSION UNITS

DOEpatents

Hoffman, J.D.; Ballou, J.K.

1957-11-19

A method and apparatus are described for removing the lighter isotope of a gaseous-liquid product from a number of diffusion columns of a liquid thermal diffusion system in two stages by the use of freeze valves. The subject liquid flows from the diffusion columns into a heated sloping capsule where the liquid is vaporized by the action of steam in a heated jacket surrounding the capsule. When the capsule is filled the gas flows into a collector. Flow between the various stages is controlled by freeze valves which are opened and closed by the passage of gas and cool water respectively through coils surrounding portions of the pipes through which the process liquid is passed. The use of the dual stage remover-collector and the freeze valves is an improvement on the thermal diffusion separation process whereby the fraction containing the lighter isotope many be removed from the tops of the diffusion columns without intercolumn flow, or prior stage flow while the contents of the capsule is removed to the final receiver.

Imaging of cauda equina edema in lumbar canal stenosis by using gadolinium-enhanced MR imaging: experimental constriction injury.

PubMed

Kobayashi, S; Uchida, K; Takeno, K; Baba, H; Suzuki, Y; Hayakawa, K; Yoshizawa, H

2006-02-01

It has been reported that disturbance of blood flow arising from circumferential compression of the cauda equina by surrounding tissue plays a major role in the appearance of neurogenic intermittent claudication (NIC) associated with lumbar spinal canal stenosis (LSCS). We created a model of LSCS to clarify the mechanism of enhancement within the cauda equina on gadolinium-enhanced MR images from patients with LSCS. In 20 dogs, a lumbar laminectomy was performed by applying circumferential constriction to the cauda equina by using a silicon tube, to produce 30% stenosis of the circumferential diameter of the dural tube. After 1 and 3 weeks, gadolinium and Evans blue albumin were injected intravenously at the same time. The sections were used to investigate the status of the blood-nerve barrier function under a fluorescence microscope and we compared gadolinium-enhanced MR images with Evans blue albumin distribution in the nerve. The other sections were used for light and transmission electron microscopic study. In this model, histologic examination showed congestion and dilation in many of the intraradicular veins, as well as inflammatory cell infiltration. The intraradicular edema caused by venous congestion and Wallerian degeneration can also occur at sites that are not subject to mechanical compression. Enhanced MR imaging showed enhancement of the cauda equina at the stenosed region, demonstrating the presence of edema. Gadolinium-enhanced MR imaging may be a useful tool for the diagnosis of microcirculatory disorders of the cauda equina associated with LSCS.

Second-stage transsphenoidal approach (TSA) for highly vascular pituicytomas in children.

PubMed

Kim, Young Gyu; Park, Young Seok

2015-06-01

A pituicytoma in the sellar area is extremely rare in children and, due to its highly vascularized nature, can be difficult to address using the transsphenoid approach (TSA) to surgery. Here, we report a rare case of a pituicytoma that was completely removed from a child through a staged operation using the TSA. A 13-year-old girl was admitted with a 1-year history of visual disturbance and amenorrhea. Visual field examination showed left total blindness and right temporal hemianopsia. Laboratory results revealed hormonal levels all within normal ranges. Brain magnetic resonance imaging (MRI) showed a homogeneous, highly enhancing sellar and suprasellar mass, typically suggestive of a pituitary adenoma. TSA surgery revealed the tumor had a rubbery-firm consistency, hypervascularity, and profuse bleeding. We removed the tumor partially and planned a second-stage operation. Gross total removal is the treatment of choice for this type of tumor. Attempted resection of these presumed adenomas or meningiomas using the TSA often results in unexpectedly heavy intraoperative bleeding due to the high vascularity of this rare tumor, making surgery challenging, especially in children where the tumor is within a relatively narrow corridor. While pituicytomas are a rare differential diagnosis for sellar or parasellar tumors in children, total removal by second-stage TSA surgery is indicated in the case of profuse bleeding or uncertainty of biopsy. Following first-stage TSA surgery and pathologic confirmation of pituicytoma, the strategy is typically gross total removal during second-stage TSA surgery. Although very rare in children, a pituicytoma should be included in the differential diagnosis of a mass in the sellar area if the tumor is highly enhancing or very vascular. Second-stage TSA surgery is another strategy when the pathology is not clear during the first-stage TSA surgery.

Simple method for quantification of gadolinium magnetic resonance imaging contrast agents using ESR spectroscopy.

PubMed

Takeshita, Keizo; Kinoshita, Shota; Okazaki, Shoko

2012-01-01

To develop an estimation method of gadolinium magnetic resonance imaging (MRI) contrast agents, the effect of concentration of Gd compounds on the ESR spectrum of nitroxyl radical was examined. A solution of either 4-oxo-2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPONE) or 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPOL) was mixed with a solution of Gd compound and the ESR spectrum was recorded. Increased concentration of gadolinium-diethylenetriamine pentaacetic acid chelate (Gd-DTPA), an MRI contrast agent, increased the peak-to-peak line widths of ESR spectra of the nitroxyl radicals, in accordance with a decrease of their signal heights. A linear relationship was observed between concentration of Gd-DTPA and line width of ESR signal, up to approximately 50 mmol/L Gd-DTPA, with a high correlation coefficient. Response of TEMPONE was 1.4-times higher than that of TEMPOL as evaluated from the slopes of the lines. The response was slightly different among Gd compounds; the slopes of calibration curves for acua[N,N-bis[2-[(carboxymethyl)[(methylcarbamoyl)methyl]amino]ethyl]glycinato(3-)]gadolinium hydrate (Gd-DTPA-BMA) (6.22 μT·L/mmol) and gadolinium-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid chelate (Gd-DOTA) (6.62 μT·L/mmol) were steeper than the slope for Gd-DTPA (5.45 μT·L/mmol), whereas the slope for gadolinium chloride (4.94 μT·L/mmol) was less steep than that for Gd-DTPA. This method is simple to apply. The results indicate that this method is useful for rough estimation of the concentration of Gd contrast agents if calibration is carried out with each standard compound. It was also found that the plot of the reciprocal square root of signal height against concentrations of contrast agents could be useful for the estimation if a constant volume of sample solution is taken and measured at the same position in the ESR cavity every time.

Acute side effects of three commonly used gadolinium contrast agents in the paediatric population.

PubMed

Neeley, Chris; Moritz, Michael; Brown, Jeffrey J; Zhou, Yihua

2016-07-01

To determine the incidence of acute side effects of three commonly used gadolinium contrast agents in the paediatric population. A retrospective review of medical records was performed to determine the incidence of acute adverse side effects of i.v. gadolinium contrast agents [MultiHance(®) (Bracco Diagnostics Inc., Princeton, NJ), Magnevist(®) (Bayer Healthcare Pharmaceuticals, Wayne, NJ) or Gadavist(®) (Bayer HealthCare Pharmaceuticals)] in paediatric patients. 40 of the 2393 patients who received gadolinium contrast agents experienced acute side effects, representing an incidence of 1.7%. The majority of the acute side effects (in 30 patients) were nausea and vomiting. The incidence was significantly higher in non-sedated patients (2.37% vs 0.7%; p = 0.0018). Furthermore, without sedation, the incidence of both nausea and vomiting was significantly higher in children receiving MultiHance, with a 4.48% incidence of nausea when compared with Magnevist (0.33%, p < 0.0001) and Gadavist (0.28%, p < 0.0001) and a 2.36% incidence of vomiting compared with those for Magnevist (0.50%, p = 0.0054) and Gadavist (0.28%, p = 0.014), whereas no difference was observed between Magnevist and Gadavist within the power of the study. In addition, there was no apparent difference between any of the three contrast agents for the incidence of allergy or other acute side effects detected, given the sample size. The gadolinium contrast agents MultiHance, Magnevist and Gadavist have a low incidence of acute side effects in the paediatric population, a rate that is further reduced in moderately sedated patients. MultiHance demonstrated significantly increased incidence of gastrointestinal symptoms compared with Magnevist and Gadavist. The incidence of acute side effects of three commonly used gadolinium contrast agents was determined in the paediatric population, which can have clinical implications.

Progressing Toward a Cohesive Pediatric 18F-FDG PET/MR Protocol: Is Administration of Gadolinium Chelates Necessary?

PubMed

Klenk, Christopher; Gawande, Rakhee; Tran, Vy Thao; Leung, Jennifer Trinh; Chi, Kevin; Owen, Daniel; Luna-Fineman, Sandra; Sakamoto, Kathleen M; McMillan, Alex; Quon, Andy; Daldrup-Link, Heike E

2016-01-01

With the increasing availability of integrated PET/MR scanners, the utility and need for MR contrast agents for combined scans is questioned. The purpose of our study was to evaluate whether administration of gadolinium chelates is necessary for evaluation of pediatric tumors on (18)F-FDG PET/MR images. First, in 119 pediatric patients with primary and secondary tumors, we used 14 diagnostic criteria to compare the accuracy of several MR sequences: unenhanced T2-weighted fast spin-echo imaging; unenhanced diffusion-weighted imaging; and-before and after gadolinium chelate contrast enhancement-T1-weighted 3-dimensional spoiled gradient echo LAVA (liver acquisition with volume acquisition) imaging. Next, in a subset of 36 patients who had undergone (18)F-FDG PET within 3 wk of MRI, we fused the PET images with the unenhanced T2-weighted MR images (unenhanced (18)F-FDG PET/MRI) and the enhanced T1-weighted MR images (enhanced (18)F-FDG PET/MRI). Using the McNemar test, we compared the accuracy of the two types of fused images using the 14 diagnostic criteria. We also evaluated the concordance between (18)F-FDG avidity and gadolinium chelate enhancement. The standard of reference was histopathologic results, surgical notes, and follow-up imaging. There was no significant difference in diagnostic accuracy between the unenhanced and enhanced MR images. Accordingly, there was no significant difference in diagnostic accuracy between the unenhanced and enhanced (18)F-FDG PET/MR images. (18)F-FDG avidity and gadolinium chelate enhancement were concordant in 30 of the 36 patients and 106 of their 123 tumors. Gadolinium chelate administration is not necessary for accurate diagnostic characterization of most solid pediatric malignancies on (18)F-FDG PET/MR images, with the possible exception of focal liver lesions. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Monte Carlo simulation of energy absorbed in phenolic ESR dosimeters added with gadolinium exposed to thermal, epithermal and fast neutrons

NASA Astrophysics Data System (ADS)

Longo, A.; Collura, G.; Gallo, S.; Bartolotta, A.; Marrale, M.

2017-11-01

In this work analyses of the energy released per unit mass in phenolic compound exposed to neutron beams were performed with the aim of predicting the increase in dose achievable by addition of gadolinium (Gd) inside the pellets. In particular, Monte Carlo (MC) simulations were carried out for IRGANOX® 1076 phenolic compound irradiated with neutron beams with different energy spectra at various depths inside a water phantom. The addition of gadolinium increases sensitivity of phenolic ESR (electron spin resonance) dosimeters to neutrons thanks to the high gadolinium cross section for neutron capture and to the large number of secondary particles (mainly Auger and internal conversion electrons) which are able to release energy inside the sensitive material layers. For small depths in water phantom and low energy neutron spectra the increase in dose due to gadolinium is large (more than a factor 50). The enhancement is smaller in case of epithermal neutron beam, whereas the increase in dose for fast neutrons is less than 50%. In order to have a comparison with other ESR dosimeters the energy released per unit mass in phenolic compound was compared with that calculated in alanine pellets. For thermal neutron beams the energy released in phenolic compound with gadolinium is comparable to that released in alanine for small depths in phantom, whereas it is larger than in alanine for large depths. In case of epithermal and fast neutron beams the energy released in phenolic compound is larger than in alanine samples because the elastic scattering with hydrogen nuclei is more probable for high neutron energies and this phenolic compound is characterized by an higher number of 1H nuclei than alanine. All results here found suggest that these phenolic pellets could be fruitfully used for dosimetric applications in Neutron Capture Therapy.

Synthesis of internally functionalized silica nanoparticles for theranostic applications

NASA Astrophysics Data System (ADS)

Walton, Nathan Isaac

This thesis addresses the synthesis and characterization of novel inorganic silica nanoparticle hybrids. It focuses in large part on their potential applications in the medical field. Silica acts as a useful carrier for a variety of compounds and this thesis silica will demonstrate its use as a carrier for boron or gadolinium. Boron-10 and gadolinium-157 have been suggested for the radiological treatment of tumor cells through the process called neutron capture therapy (NCT). Gadolinium is also commonly used as a Magnetic Resonance Imaging (MRI) contrast agent. Particles that carry it have potential theranostic applications of both imaging and treating tumors. Chapter 1 presents a background on synthetic strategies and usages of silica nanoparticles, and NCT theory. Chapter 2 describes a procedure to create mesoporous metal chelating silica nanoparticles, mDTTA. This is achieved via a co-condensation of tetraethoxysilane (TEOS) and 3-trimethoxysilyl-propyl diethylenetriamine (SiDETA) followed by a post-synthesis modification step with bromoacetic acid (BrAA). These particles have a large surface area and well-defined pores of ~2 nm. The mDTTA nanoparticles were used to chelate the copper(II), cobalt(II) and gadolinium(III). The chelating of gadolinium is the most interesting since it can be used as a MRI contrast agent and a neutron capture therapeutic. The synthetic procedure developed also allows for the attachment of a fluorophore that gives the gadolinium chelating mDTTA nanoparticles a dual imaging modality. Chapter 3 presents the synthetic method used to produce two classes of large surface area organically modified silica (ORMOSIL) nanoparticles. Condensating the organosilane vinyltrimethoxysilane in a micellar solution results in nanoparticles that are either surface rough (raspberry-like) or mesoporous nanoparticles, which prior to this thesis has not been demonstrated in ORMOSIL chemistry. Furthermore, the vinyl functionalities are modified, using hydroboration, to make the nanoparticles into water-dispersible boron carriers that also have potential boron neutron capture therapy (BNCT) applications. Lastly, Chapter 4 provides a general description of NCT, specifically that involving boron-10 and gadolinium-157. It further describes the synthetic methodology used in producing fatty acid coated boron nanoparticles (BNPs). The BNPs are encapsulated with silica to add a hydrophilic shell so that they can potentially be used in biological systems as BNCT agents. The silica shell is also modified with a fluorophore, dansyl chloride, so that the particle hybrid could be imaged during cell studies.

Nitrogen removal from natural gas using two types of membranes

DOEpatents

Baker, Richard W.; Lokhandwala, Kaaeid A.; Wijmans, Johannes G.; Da Costa, Andre R.

2003-10-07

A process for treating natural gas or other methane-rich gas to remove excess nitrogen. The invention relies on two-stage membrane separation, using methane-selective membranes for the first stage and nitrogen-selective membranes for the second stage. The process enables the nitrogen content of the gas to be substantially reduced, without requiring the membranes to be operated at very low temperatures.

Method and apparatus for converting and removing organosulfur and other oxidizable compounds from distillate fuels, and compositions obtained thereby

DOEpatents

D'Alessandro, Robert N.; Tarabocchia, John; Jones, Jerald Andrew; Bonde, Steven E.; Leininger, Stefan

2010-10-26

The present disclosure is directed to a multi-stage system and a process utilizing said system with the design of reducing the sulfur-content in a liquid comprising hydrocarbons and organosulfur compounds. The process comprising at least one of the following states: (1) an oxidation stage; (2) an extraction state; (3) a raffinate washing stage; (4) a raffinate polishing stage; (5) a solvent recovery stage; (6) a solvent purification stage; and (7) a hydrocarbon recovery stage. The process for removing sulfur-containing hydrocarbons from gas oil, which comprises oxidizing gas oil comprising hydrocarbons and organosulfur compounds to obtain a product gas oil.

Modeling and Simulation of the ARES UPPER STAGE Transportation, Lifting, Stacking and Mating Operations Within the Vehicle Assembly Building at KSC

NASA Technical Reports Server (NTRS)

Kromis, Phillip A.

2010-01-01

This viewgraph presentation describes the modeling and simulation of the Ares Upper Stage Transportation, lifting, stacking, and mating operations within the Vehicle Assembly Building (VAB) at Kennedy Space Center (KSC). An aerial view of KSC Launch Shuttle Complex, two views of the Delmia process control layout, and an upper stage move subroutine and breakdown are shown. An overhead image of the VAB and the turning basin along with the Pegasus barge at the turning basin are also shown. This viewgraph presentation also shows the actual design and the removal of the mid-section spring tensioners, the removal of the AFT rear and forward tensioners tie downs, and removing the AFT hold down post and mount. US leaving the Pegasus Barge, the upper stage arriving at transfer aisle, upper stage receiving/inspection in transfer aisle, and an overhead view of upper stage receiving/inspection in transfer aisle are depicted. Five views of the actual connection of the cabling to the upper stage aft lifting hardware are shown. The upper stage transporter forward connector, two views of the rotation horizontal to vertical, the disconnection of the rear bolt ring cabling, the lowering of the upper stage to the inspection stand, disconnection of the rear bolt ring from the upper stage, the lifting of the upper stage and inspection of AFT fange, and the transfer of upper stage in an integrated stack are shown. Six views of the mating of the upper stage to the first stage are depicted. The preparation, inspection, and removal of the forward dome are shown. The upper stage mated on the integrated stack and crawler is also shown. This presentation concludes with A Rapid Upper Limb Assessment (RULA) utilizing male and female models for assessing risk factors to the upper extremities of human beings in an actual physical environment.

Dynamic global model of oxide Czochralski process with weighing control

NASA Astrophysics Data System (ADS)

Mamedov, V. M.; Vasiliev, M. G.; Yuferev, V. S.

2011-03-01

A dynamic model of oxide Czochralski growth with weighing control has been developed for the first time. A time-dependent approach is used for the calculation of temperature fields in different parts of a crystallization set-up and convection patterns in a melt, while internal radiation in crystal is considered in a quasi-steady approximation. A special algorithm is developed for the calculation of displacement of a triple point and simulation of a crystal surface formation. To calculate variations in the heat generation, a model of weighing control with a commonly used PID regulator is applied. As an example, simulation of the growth process of gallium-gadolinium garnet (GGG) crystals starting from the stage of seeding is performed.

Use of gadolinium chloride as a contrast agent for imaging spruce knots by magnetic resonance

Treesearch

Thomas L. Eberhardt; Chi-Leung So; Amy H. Herlihy; Po-Wah So

2006-01-01

Treatments of knot-containing spruce wood blocks with a paramagnetic salt, gadolinium (III) chloride, in combination with solvent pretreatments, were evaluated as strategies to enhance the visualization of wood features by magnetic resonance imaging (MRI). Initial experiments with clear wood and excised knot samples showed differences in moisture uptake after...

CONTROL ROD FOR A NUCLEAR REACTOR AND METHOD OF PREPARATION

DOEpatents

Hausner, H.H.

1958-12-30

BS>An improved control rod is presented for a nuclear reactor. This control rod is comprised of a rare earth metal oxide or rare earth metal carbide such as gadolinium oxide or gadolinium carbide, uniformly distributed in a metal matrix having a low cross sectional area of absorption for thermal neutrons, such as aluminum, beryllium, and zirconium.

Layered gadolinium hydroxides for low-temperature magnetic cooling.

PubMed

Abellán, Gonzalo; Espallargas, Guillermo Mínguez; Lorusso, Giulia; Evangelisti, Marco; Coronado, Eugenio

2015-09-28

Layered gadolinium hydroxides have revealed to be excellent candidates for cryogenic magnetic refrigeration. These materials behave as pure 2D magnetic systems with a Heisenberg-Ising critical crossover, induced by dipolar interactions. This 2D character and the possibility offered by these materials to be delaminated open the possibility of rapid heat dissipation upon substrate deposition.

Rapid colorimetric sensing of gadolinium by EGCG-derived AgNPs: the development of a nanohybrid bioimaging probe.

PubMed

Singh, Rohit Kumar; Mishra, Sourav; Jena, Satyapriya; Panigrahi, Bijayananda; Das, Bhaskar; Jayabalan, Rasu; Parhi, Pankaj Kumar; Mandal, Dindyal

2018-04-17

Polyphenol functionalized silver nanoparticles (AgNPs) have been developed and demonstrated as colorimetric sensors for the selective detection of gadolinium. The newly obtained AgNP-Gd3+ conjugates exhibit high aqueous dispersibility and excitation dependent fluorescence emission. The conjugates offer multicolor bioimaging potential owing to their excellent luminescence properties.

Neutron Absorbing Alloys

DOEpatents

Mizia, Ronald E.; Shaber, Eric L.; DuPont, John N.; Robino, Charles V.; Williams, David B.

2004-05-04

The present invention is drawn to new classes of advanced neutron absorbing structural materials for use in spent nuclear fuel applications requiring structural strength, weldability, and long term corrosion resistance. Particularly, an austenitic stainless steel alloy containing gadolinium and less than 5% of a ferrite content is disclosed. Additionally, a nickel-based alloy containing gadolinium and greater than 50% nickel is also disclosed.

[Gadolinium-based contrast agents for magnetic resonance imaging].

PubMed

Carrasco Muñoz, S; Calles Blanco, C; Marcin, Javier; Fernández Álvarez, C; Lafuente Martínez, J

2014-06-01

Gadolinium-based contrast agents are increasingly being used in magnetic resonance imaging. These agents can improve the contrast in images and provide information about function and metabolism, increasing both sensitivity and specificity. We describe the gadolinium-based contrast agents that have been approved for clinical use, detailing their main characteristics based on their chemical structure, stability, and safety. In general terms, these compounds are safe. Nevertheless, adverse reactions, the possibility of nephrotoxicity from these compounds, and the possibility of developing nephrogenic systemic fibrosis will be covered in this article. Lastly, the article will discuss the current guidelines, recommendations, and contraindications for their clinical use, including the management of pregnant and breast-feeding patients. Copyright © 2014 SERAM. Published by Elsevier Espana. All rights reserved.

Gadolinium-based nanoparticles for highly efficient T1-weighted magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Lim, Eun-Kyung; Kang, Byunghoon; Choi, Yuna; Jang, Eunji; Han, Seungmin; Lee, Kwangyeol; Suh, Jin-Suck; Haam, Seungjoo; Huh, Yong-Min

2014-06-01

We developed Pyrene-Gadolinium (Py-Gd) nanoparticles as pH-sensitive magnetic resonance imaging (MRI) contrast agents capable of showing a high-Mr signal in cancer-specific environments, such as acidic conditions. Py-Gd nanoparticles were prepared by coating Py-Gd, which is a complex of gadolinium with pyrenyl molecules, with pyrenyl polyethyleneglycol PEG using a nano-emulsion method. These particles show better longitudinal relaxation time (T1) MR signals in acidic conditions than they do in neutral conditions. Furthermore, the particles exhibit biocompatibility and MR contrast effects in both in vitro and in vivo studies. From these results, we confirm that Py-Gd nanoparticles have the potential to be applied for accurate cancer diagnosis and therapy.

The evolution of gadolinium based contrast agents: from single-modality to multi-modality

NASA Astrophysics Data System (ADS)

Zhang, Li; Liu, Ruiqing; Peng, Hui; Li, Penghui; Xu, Zushun; Whittaker, Andrew K.

2016-05-01

Gadolinium-based contrast agents are extensively used as magnetic resonance imaging (MRI) contrast agents due to their outstanding signal enhancement and ease of chemical modification. However, it is increasingly recognized that information obtained from single modal molecular imaging cannot satisfy the higher requirements on the efficiency and accuracy for clinical diagnosis and medical research, due to its limitation and default rooted in single molecular imaging technique itself. To compensate for the deficiencies of single function magnetic resonance imaging contrast agents, the combination of multi-modality imaging has turned to be the research hotpot in recent years. This review presents an overview on the recent developments of the functionalization of gadolinium-based contrast agents, and their application in biomedicine applications.

Successful Insular Glioma Removal in a Deaf Signer Patient During an Awake Craniotomy Procedure.

PubMed

Metellus, Philippe; Boussen, Salah; Guye, Maxime; Trebuchon, Agnes

2017-02-01

Resection of tumors located within the insula of the dominant hemisphere represents a technical challenge because of the complex anatomy, including the surrounding vasculature, and the relationship to functional (motor and language) structures. We report here the case of a successful resection of a left insular glioma in a native deaf signer during an awake craniotomy. The patient, a congenitally deaf right-handed patient who is a native user of sign language, presented with a seizure 1 week before he was referred to our department. Magnetic resonance imaging revealed a left heterogeneous insular tumor enhanced after intravenous gadolinium infusion. Because of its deep and dominant hemisphere location, an awake craniotomy was decided. The patient was evaluated intraoperatively using object naming, text reading, and sign repetition tasks. An isolated inferior frontal gyrus site evoked repeated object naming errors. A transopercular parietal approach was performed and allowed the successful removal of the tumor under direct electric stimulation and electrocorticography. To our knowledge, this is the first report of successful removal of a left insular tumor without any functional sequelae in a native deaf signer using intraoperative direct cerebral stimulation during an awake craniotomy. The methodology used also provides the first evidence of the actual anatomo-functional organization of language in deaf signers. Copyright © 2016 Elsevier Inc. All rights reserved.

Two-stage soil infiltration treatment system for treating ammonium wastewaters of low COD/TN ratios.

PubMed

Lei, Zhongfang; Wu, Ting; Zhang, Yi; Liu, Xiang; Wan, Chunli; Lee, Duu-Jong; Tay, Joo-Hwa

2013-01-01

Soil infiltration treatment (SIT) is ineffective to treat ammonium wastewaters of total nitrogen (TN) > 100 mg l(-1). This study applied a novel two-stage SIT process for effective TN removal from wastewaters of TN>100 mg l(-1) and of chemical oxygen demand (COD)/TN ratio of 3.2-8.6. The wastewater was first fed into the soil column (stage 1) at hydraulic loading rate (HLR) of 0.06 m(3) m(-2) d(-1) for COD removal and total phosphorus (TP) immobilization. Then the effluent from stage 1 was fed individually into four soil columns (stage 2) at 0.02 m(3) m(-2) d(-1) of HLR with different proportions of raw wastewater as additional carbon source. Over the one-year field test, balanced nitrification and denitrification in the two-stage SIT revealed excellent TN removal (>90%) from the tested wastewaters. Copyright © 2012 Elsevier Ltd. All rights reserved.

Method of CO.sub.2 removal from a gasesous stream at reduced temperature

DOEpatents

Fisher, James C; Siriwardane, Ranjani V; Berry, David A; Richards, George A

2014-11-18

A method for the removal of H.sub.2O and CO.sub.2 from a gaseous stream comprising H.sub.2O and CO.sub.2, such as a flue gas. The method initially utilizes an H.sub.2O removal sorbent to remove some portion of the H.sub.2O, producing a dry gaseous stream and a wet H.sub.2O removal sorbent. The dry gaseous stream is subsequently contacted with a CO.sub.2 removal sorbent to remove some portion of the CO.sub.2, generating a dry CO.sub.2 reduced stream and a loaded CO.sub.2 removal sorbent. The loaded CO.sub.2 removal sorbent is subsequently heated to produce a heated CO.sub.2 stream. The wet H.sub.2O removal sorbent and the dry CO.sub.2 reduced stream are contacted in a first regeneration stage, generating a partially regenerated H.sub.2O removal sorbent, and the partially regenerated H.sub.2O removal sorbent and the heated CO.sub.2 stream are subsequently contacted in a second regeneration stage. The first and second stage regeneration typically act to retain an initial monolayer of moisture on the various removal sorbents and only remove moisture layers bound to the initial monolayer, allowing for relatively low temperature and pressure operation. Generally the applicable H.sub.2O sorption/desorption processes may be conducted at temperatures less than about 70.degree. C. and pressures less than 1.5 atmospheres, with certain operations conducted at temperatures less than about 50.degree. C.

Biomedical Nanocrystal Agents: Design, Synthesis, and Applications

NASA Astrophysics Data System (ADS)

Cho, Minjung

In these days, nanomaterials are applied in a variety of biomedical applications including magnetic resonance imaging (MRI), cell imaging, drug delivery, and cell separation. Most MRI contrast agents affect the longitudinal relaxation time (T1) and transverse relaxation time (T2 ) of water protons in the tissue and result in increased positive or negative contrast. Here, we report the optimization of r1 (1/T 1) or r2 (1/T2) relaxivity dynamics with diameter controlled gadolinium oxide nanocrystals (2˜22 nm) and iron based magnetic nanocrystals (4 ˜33 nm). The r1 and r2 MR relaxivity values of hydrated nanocrystals were optimized and examined depending on their core diameter, surface coating, and compositions; the high r1 value of gadolinium oxide was 40-60 S-1mM-1, which is 10-15 fold higher than that of commercial Gd (III) chelates (4.3˜4.6 S-1mM-1). Moreover, in vitro toxicological studies revealed that polymer coated nanocrystals suspensions had no significant effect on human dermal fibroblast (HDF) cells even at high concentration. Towards multimodal imaging or multifunctional ability, we developed the iron oxide/QDs complexes, which consist of cores of iron oxide that act as nucleation sites for fluorescent QDs. The choice of variable QDs helped to visualize and remove large iron oxide materials in a magnetic separation. Additionally, diluted materials concentrated on the magnet could be fluorescently detected even at very low concentration. The designed MRI or multifunctional nanomaterials will give great and powerful uses in biomedical applications.

Treating low carbon/nitrogen (C/N) wastewater in simultaneous nitrification-endogenous denitrification and phosphorous removal (SNDPR) systems by strengthening anaerobic intracellular carbon storage.

PubMed

Wang, Xiaoxia; Wang, Shuying; Xue, Tonglai; Li, Baikun; Dai, Xian; Peng, Yongzhen

2015-06-15

A novel simultaneous nitrification denitrification and phosphorous removal-sequencing batch reactor (SNDPR-SBR) enriched with PAOs (phosphorus accumulating organisms), DPAOs (denitrifying PAOs), and GAOs (glycogen accumulating organisms) at the ratio of 2:1:1 was developed to achieve the simultaneous nutrient and carbon removal treating domestic wastewater with low carbon/nitrogen ratio (≤3.5). The SNDPR system was operated for 120 days at extended anaerobic stage (3 h) and short aerobic stage at low oxygen concentration (2.5 h) with short sludge retention time (SRT) of 10.9 d and hydraulic retention time (HRT) of 14.6 h. The results showed that at the stable operating stage, the average effluent chemical oxygen demand (COD) and PO4(3-)-P concentrations were 47.2 and 0.2 mg L(-1), respectively, the total nitrogen (TN) removal efficiency was 77.7%, and the SND efficiency reached 49.3%. Extended anaerobic stage strengthened the intracellular carbon (mainly poly-β-hydroxybutyrate, PHB) storage, efficiently utilized the organic substances in wastewater, and provided sufficient carbon sources for denitrification and phosphorus uptake without external carbon addition. Short aerobic stage at low oxygen concentration (dissolved oxygen (DO): 1 ± 0.3 mg L(-1)) achieved a concurrence of nitrification, endogenous denitrification, denitrifying and aerobic phosphorus uptake, and saved about 65% energy consumption for aeration. Microbial community analysis demonstrated that P removal was mainly performed by aerobic PAOs while N removal was mainly carried out by denitrifying GAOs (DGAOs), even though DPAOs were also participated in both N and P removal. Copyright © 2015 Elsevier Ltd. All rights reserved.

Intravital Microscopy for Identifying Tumor Vessels in Patients With Stage IA-IV Melanoma That is Being Removed by Surgery

ClinicalTrials.gov

2017-06-05

Recurrent Melanoma; Stage IA Skin Melanoma; Stage IB Skin Melanoma; Stage IIA Skin Melanoma; Stage IIB Skin Melanoma; Stage IIC Skin Melanoma; Stage IIIA Skin Melanoma; Stage IIIB Skin Melanoma; Stage IIIC Skin Melanoma; Stage IV Skin Melanoma

[Studies of three-dimensional cardiac late gadolinium enhancement MRI at 3.0 Tesla].

PubMed

Ishimoto, Takeshi; Ishihara, Masaru; Ikeda, Takayuki; Kawakami, Momoe

2008-12-20

Cardiac late Gadolinium enhancement MR imaging has been shown to allow assessment of myocardial viability in patients with ischemic heart disease. The current standard approach is a 3D inversion recovery sequence at 1.5 Tesla. The aims of this study were to evaluate the technique feasibility and clinical utility of MR viability imaging at 3.0 Tesla in patients with myocardial infarction and cardiomyopathy. In phantom and volunteer studies, the inversion time required to suppress the signal of interests and tissues was prolonged at 3.0 Tesla. In the clinical study, the average inversion time to suppress the signal of myocardium at 3.0 Tesla with respect to MR viability imaging at 1.5 Tesla was at 15 min after the administration of contrast agent (304.0+/-29.2 at 3.0 Tesla vs. 283.9+/-20.9 at 1.5 Tesla). The contrast between infarction and viable myocardium was equal at both field strengths (4.06+/-1.30 at 3.0 Tesla vs. 4.42+/-1.85 at 1.5 Tesla). Even at this early stage, MR viability imaging at 3.0 Tesla provides high quality images in patients with myocardial infarction. The inversion time is significantly prolonged at 3.0 Tesla. The contrast between infarction and viable myocardium at 3.0 Tesla are equal to 1.5 Tesla. Further investigation is needed for this technical improvement, for clinical evaluation, and for limitations.

Assessment of liver function in primary biliary cirrhosis using Gd-EOB-DTPA-enhanced liver MRI.

PubMed

Nilsson, Henrik; Blomqvist, Lennart; Douglas, Lena; Nordell, Anders; Jonas, Eduard

2010-10-01

Gd-EOB-DTPA (gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid) is a gadolinium-based hepatocyte-specific contrast agent for magnetic resonance imaging (MRI). The aim of this study was to determine whether the hepatic uptake and excretion of Gd-EOB-DTPA differ between patients with primary biliary cirrhosis (PBC) and healthy controls, and whether differences could be quantified. Gd-EOB-DTPA-enhanced liver MRI was performed in 20 healthy volunteers and 12 patients with PBC. The uptake of Gd-EOB-DTPA was assessed using traditional semi-quantitative parameters (C(max) , T(max) and T(1/2) ), as well as model-free parameters derived after deconvolutional analysis (hepatic extraction fraction [HEF], input-relative blood flow [irBF] and mean transit time [MTT]). In each individual, all parameters were calculated for each liver segment and the median of the segmental values was used to define a global liver median (GLM). Although the PBC patients had relatively mild disease according to their Model for End-stage Liver Disease (MELD), Child-Pugh and Mayo risk scores, they had significantly lower HEF and shorter MTT values compared with the healthy controls. These differences significantly increased with increasing MELD and Child-Pugh scores. Dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) has a potential role as an imaging-based liver function test. The high spatial resolution of MRI enables hepatic function to be assessed on segmental and sub-segmental levels. © 2010 International Hepato-Pancreato-Biliary Association.

Ablation plume structure and dynamics in ambient gas observed by laser-induced fluorescence imaging spectroscopy

NASA Astrophysics Data System (ADS)

Miyabe, M.; Oba, M.; Iimura, H.; Akaoka, K.; Khumaeni, A.; Kato, M.; Wakaida, I.

2015-08-01

The dynamic behavior of an ablation plume in ambient gas has been investigated by laser-induced fluorescence imaging spectroscopy. The second harmonic beam from an Nd:YAG laser (0.5-6 J/cm2) was focused on a sintered oxide pellet or a metal chip of gadolinium. The produced plume was subsequently intersected with a sheet-shaped UV beam from a dye laser so that time-resolved fluorescence images were acquired with an intensified CCD camera at various delay times. The obtained cross-sectional images of the plume indicate that the ablated ground state atoms and ions of gadolinium accumulate in a hemispherical contact layer between the plume and the ambient gas, and a cavity containing a smaller density of ablated species is formed near the center of the plume. At earlier expansion stage, another luminous component also expands in the cavity so that it coalesces into the hemispherical layer. The splitting and coalescence for atomic plume occur later than those for ionic plume. Furthermore, the hemispherical layer of neutral atoms appears later than that of ions; however, the locations of the layers are nearly identical. This coincidence of the appearance locations of the layers strongly suggests that the neutral atoms in the hemispherical layer are produced as a consequence of three-body recombination of ions through collisions with gas atoms. The obtained knowledge regarding plume expansion dynamics and detailed plume structure is useful for optimizing the experimental conditions for ablation-based spectroscopic analysis.

Synthesis and characterization of protocatechuic acid-loaded gadolinium-layered double hydroxide and gold nanocomposite for theranostic application

NASA Astrophysics Data System (ADS)

Usman, Muhammad Sani; Hussein, Mohd Zobir; Kura, Aminu Umar; Fakurazi, Sharida; Masarudin, Mas Jaffri; Saad, Fathinul Fikri Ahmad

2018-03-01

A theranostic nanocomposite was developed using anticancer agent, protocatechuic acid (PA) and magnetic resonance imaging (MRI) contrast agent gadolinium nitrate (Gd) for simultaneous delivery using layered double hydroxide (LDH) as the delivery agent. Gold nanoparticles (AuNPs) were adsorbed on the surface of the LDH, which served as a complementary contrast agent. Based on the concept of supramolecular chemistry (SPC) and multimodal delivery system (MDS), the PA and Gd guests were first intercalated into the LDH host and subsequently AuNPs were surface adsorbed as the third guest. The nanohybrid developed was named MAPGAu. The MAPGAu was exposed to various characterizations at different stages of synthesis, starting with XRD analysis, which was used to confirm the intercalation episode and surface adsorption of the guest molecules. Consequently, FESEM, Hi-TEM, XRD, ICP-OES, CHNS, FTIR and UV-Vis analyses were done on the nanohybrids. The result of XRD analysis indicated successful intercalation of the Gd and PA as well the adsorption of AuNPs. The UV-Vis release study showed 90% of the intercalated drug was released at pH 4.8, which is the pH of the cancer cells. The FESEM and TEM micrographs obtained equally confirmed the formation of MAGPAu nanocomposite, with AuNPs conspicuously deposited on the LDH surface. The cytotoxicity study of the nanohybrid also showed insignificant toxicity to normal cell lines and significant toxicity to cancer cell lines. The developed MAGPAu nanocomposite has shown prospects for future theranostic cancer treatment.

Gadolinium-loaded polymeric nanoparticles modified with Anti-VEGF as multifunctional MRI contrast agents for the diagnosis of liver cancer.

PubMed

Liu, Yongjun; Chen, Zhijin; Liu, Chunxi; Yu, Dexin; Lu, Zaijun; Zhang, Na

2011-08-01

Molecular imaging is essential to increase the sensitivity and selectivity of cancer diagnosis especially in the early stage of tumor. Here, we designed a novel multifunctional polymeric nanoparticle contrast agent (Anti-VEGF PLA-PEG-PLL-Gd NP) simultaneously modified with Gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) and anti-vascular endothelial growth factor (VEGF) antibody to deliver Gd-DTPA to the tumor area and achieve the early diagnosis of hepatocellular carcinoma (HCC). The Anti-VEGF PLA-PEG-PLL-Gd NPs exhibited high T(1) relaxivity and no obvious cytotoxicity under the experimental concentrations in human hepatocellular carcinoma (HepG2) cells. The results of in vitro cell uptake experiments demonstrated that the uptake process of NPs was both concentration and time depended. Compared with non-targeted NPs, the Anti-VEGF antibody modified NPs showed much higher cell uptake in the HepG2 cells. During in vivo studies, the targeted NPs showed significantly signal intensity enhancement at the tumor site (mouse hepatocarcinoma tumor, H22) compared with non-targeted NPs and Gd-DTPA injection in tumor-bearing mice and the imaging time was significantly prolonged from less than an hour (Gd-DTPA injection group) to 12 h. These results demonstrated that this novel MRI contrast agent Anti-VEGF PLA-PEG-PLL-Gd NPs showed great potential in the early diagnosis of liver tumors. Copyright © 2011 Elsevier Ltd. All rights reserved.

Complex magnetism of lanthanide intermetallics and the role of their valence electrons: Ab Initio theory and experiment

DOE PAGES

Petit, L.; Paudyal, D.; Mudryk, Y.; ...

2015-11-09

We explain a profound complexity of magnetic interactions of some technologically relevant gadolinium intermetallics using an ab initio electronic structure theory which includes disordered local moments and strong f-electron correlations. The theory correctly finds GdZn and GdCd to be simple ferromagnets and predicts a remarkably large increase of Curie temperature with a pressure of +1.5 K kbar –1 for GdCd confirmed by our experimental measurements of +1.6 K kbar –1. Moreover, we find the origin of a ferromagnetic-antiferromagnetic competition in GdMg manifested by noncollinear, canted magnetic order at low temperatures. As a result, replacing 35% of the Mg atoms withmore » Zn removes this transition, in excellent agreement with long-standing experimental data.« less

Sensitive and transportable gadolinium-core plastic scintillator sphere for neutron detection and counting

NASA Astrophysics Data System (ADS)

Dumazert, Jonathan; Coulon, Romain; Carrel, Frédérick; Corre, Gwenolé; Normand, Stéphane; Méchin, Laurence; Hamel, Matthieu

2016-08-01

Neutron detection forms a critical branch of nuclear-related issues, currently driven by the search for competitive alternative technologies to neutron counters based on the helium-3 isotope. The deployment of plastic scintillators shows a high potential for efficient detectors, safer and more reliable than liquids, more easily scalable and cost-effective than inorganic. In the meantime, natural gadolinium, through its 155 and mostly 157 isotopes, presents an exceptionally high interaction probability with thermal neutrons. This paper introduces a dual system including a metal gadolinium core inserted at the center of a high-scale plastic scintillator sphere. Incident fast neutrons are thermalized by the scintillator shell and then may be captured with a significant probability by gadolinium 155 and 157 nuclei in the core. The deposition of a sufficient fraction of the capture high-energy prompt gamma signature inside the scintillator shell will then allow discrimination from background radiations by energy threshold, and therefore neutron detection. The scaling of the system with the Monte Carlo MCNPX2.7 code was carried out according to a tradeoff between the moderation of incident fast neutrons and the probability of slow neutron capture by a moderate-cost metal gadolinium core. Based on the parameters extracted from simulation, a first laboratory prototype for the assessment of the detection method principle has been synthetized. The robustness and sensitivity of the neutron detection principle are then assessed by counting measurement experiments. Experimental results confirm the potential for a stable, highly sensitive, transportable and cost-efficient neutron detector and orientate future investigation toward promising axes.

Electrical and Structural Substrate of Arrhythmogenic Right Ventricular Cardiomyopathy Determined Using Noninvasive Electrocardiographic Imaging and Late Gadolinium Magnetic Resonance Imaging.

PubMed

Andrews, Christopher M; Srinivasan, Neil T; Rosmini, Stefania; Bulluck, Heerajnarain; Orini, Michele; Jenkins, Sharon; Pantazis, Antonis; McKenna, William J; Moon, James C; Lambiase, Pier D; Rudy, Yoram

2017-07-01

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a significant cause of sudden cardiac death in the young. Improved noninvasive assessment of ARVC and better understanding of the disease substrate are important for improving patient outcomes. We studied 20 genotyped ARVC patients with a broad spectrum of disease using electrocardiographic imaging (a method for noninvasive cardiac electrophysiology mapping) and advanced late gadolinium enhancement cardiac magnetic resonance scar imaging. Compared with 20 healthy controls, ARVC patients had longer ventricular activation duration (median, 52 versus 42 ms; P =0.007) and prolonged mean epicardial activation-recovery intervals (a surrogate for local action potential duration; median, 275 versus 241 ms; P =0.014). In these patients, we observed abnormal and varied epicardial activation breakthrough locations and regions of nonuniform conduction and fractionated electrograms. Nonuniform conduction and fractionated electrograms were present in the early concealed phase of ARVC. Electrophysiological abnormalities colocalized with late gadolinium enhancement scar, indicating a relationship with structural disease. Premature ventricular contractions were common in ARVC patients with variable initiation sites in both ventricles. Premature ventricular contraction rate increased with exercise, and within anatomic segments, it correlated with prolonged repolarization, electric markers of scar, and late gadolinium enhancement (all P <0.001). Electrocardiographic imaging reveals electrophysiological substrate properties that differ in ARVC patients compared with healthy controls. A novel mechanistic finding is the presence of repolarization abnormalities in regions where ventricular ectopy originates. The results suggest a potential role for electrocardiographic imaging and late gadolinium enhancement in early diagnosis and noninvasive follow-up of ARVC patients. © 2017 American Heart Association, Inc.

Liver acquisition with acceleration volume acquisition gadolinium-enhanced magnetic resonance combined with T2 sequences in the diagnosis of local recurrence of rectal cancer.

PubMed

Cao, Wuteng; Li, Fangqian; Gong, Jiaying; Liu, Dechao; Deng, Yanhong; Kang, Liang; Zhou, Zhiyang

2016-11-22

To investigate the efficacy of liver acquisition with acceleration volume acquisition (LAVA) gadolinium-enhanced magnetic resonance (MR) sequences and to assess its added accuracy in diagnosing local recurrence (LR) of rectal cancer with conventional T2-weighted fast spin echo (FSE) sequences. Pelvic MRI, including T2-weighted FSE sequences, gadolinium-enhanced sequences of LAVA and T1-weighted FSE with fat suppression, was performed on 225 patients with postoperative rectal cancer. Two readers evaluated the presence of LR according to "T2" (T2 sequences only), "T2 + LAVA-Gad" (LAVA and T2 imaging), and "T2 + T1-fs-Gad" (T1 fat suppression-enhanced sequence with T2 images). To evaluate diagnostic efficiency, imaging quality with LAVA and T1-fs-Gad by subjective scores and the signal intensity (SI) ratio. In the result, the SI ratio of LAVA was significantly higher than that of T1-fs-Gad (p = 0.0001). The diagnostic efficiency of "T2 + LAVA-Gad" was better than that of "T2 + T1-fs-Gad" (p = 0.0016 for Reader 1, p = 0.0001 for Reader 2) and T2 imaging only (p = 0.0001 for Reader 1; p = 0.0001 for Reader 2). Therefore, LAVA gadolinium-enhanced MR increases the accuracy of diagnosis of LR from rectal cancer and could replace conventional T1 gadolinium-enhanced sequences in the postoperative pelvic follow-up of rectal cancer.

Investigations into the mechanism of material removal and surface modification at atomic scale on stainless steel using molecular dynamics simulation

NASA Astrophysics Data System (ADS)

Ranjan, Prabhat; Balasubramaniam, R.; Jain, V. K.

2018-06-01

A molecular dynamics simulation (MDS) has been carried out to investigate the material removal phenomenon of chemo-mechanical magnetorheological finishing (CMMRF) process. To understand the role of chemical assisted mechanical abrasion in CMMRF process, material removal phenomenon is subdivided into three different stages. In the first stage, new atomic bonds viz. Fe-O-Si is created on the surface of the workpiece (stainless steel). The second stage deals with the rupture of parent bonds like Fe-Fe on the workpiece. In the final stage, removal of material from the surface in the form of dislodged debris (cluster of atoms) takes place. Effects of process parameters like abrasive particles, depth of penetration and initial surface condition on finishing force, potential energy (towards secondary phenomenon such as chemical instability of the finished surface) and material removal at atomic scale have been investigated. It was observed that the type of abrasive particle is one of the important parameters to produce atomically smooth surface. Experiments were also conducted as per the MDS to generate defect-free and sub-nanometre-level finished surface (Ra value better than 0.2 nm). The experimental results reasonably agree well with the simulation results.

Booster Vaccination in Preventing Disease Recurrence in Previously Vaccinated Patients With Melanoma That Has Been Removed By Surgery

ClinicalTrials.gov

2015-01-23

Recurrent Melanoma; Stage IA Skin Melanoma; Stage IB Skin Melanoma; Stage IIA Skin Melanoma; Stage IIB Skin Melanoma; Stage IIC Skin Melanoma; Stage IIIA Skin Melanoma; Stage IIIB Skin Melanoma; Stage IIIC Skin Melanoma; Stage IV Skin Melanoma

Quantitative Susceptibility Mapping and R2* Measured Changes during White Matter Lesion Development in Multiple Sclerosis: Myelin Breakdown, Myelin Debris Degradation and Removal, and Iron Accumulation.

PubMed

Zhang, Y; Gauthier, S A; Gupta, A; Chen, W; Comunale, J; Chiang, G C-Y; Zhou, D; Askin, G; Zhu, W; Pitt, D; Wang, Y

2016-09-01

Quantitative susceptibility mapping and R2* are sensitive to myelin and iron changes in multiple sclerosis lesions. This study was designed to characterize lesion changes on quantitative susceptibility mapping and R2* at various gadolinium-enhancement stages. This study included 64 patients with MS with different enhancing patterns in white matter lesions: nodular, shell-like, nonenhancing < 1 year old, and nonenhancing 1-3 years old. These represent acute, late acute, early chronic, and late chronic lesions, respectively. Susceptibility values measured on quantitative susceptibility mapping and R2* values were compared among the 4 lesion types. Their differences were assessed with a generalized estimating equation, controlling for Expanded Disability Status Scale score, age, and disease duration. We analyzed 203 lesions: 80 were nodular-enhancing, of which 77 (96.2%) were isointense on quantitative susceptibility mapping; 33 were shell-enhancing, of which 30 (90.9%) were hyperintense on quantitative susceptibility mapping; and 49 were nonenhancing lesions < 1 year old and 41 were nonenhancing lesions 1-3 years old, all of which were hyperintense on quantitative susceptibility mapping. Their relative susceptibility/R2* values were 0.5 ± 4.4 parts per billion/-5.6 ± 2.9 Hz, 10.2 ± 5.4 parts per billion/-8.0 ± 2.6 Hz, 20.2 ± 7.8 parts per billion/-3.1 ± 2.3 Hz, and 33.2 ± 8.2 parts per billion/-2.0 ± 2.6 Hz, respectively, and were significantly different (P < .005). Early active MS lesions with nodular enhancement show R2* decrease but no quantitative susceptibility mapping change, reflecting myelin breakdown; late active lesions with peripheral enhancement show R2* decrease and quantitative susceptibility mapping increase in the lesion center, reflecting further degradation and removal of myelin debris; and early or late chronic nonenhancing lesions show both quantitative susceptibility mapping and R2* increase, reflecting iron accumulation. © 2016 by American Journal of Neuroradiology.

Investigation of Magnetostatic Surface Waves for Anisotropic Effects.

DTIC Science & Technology

1986-06-01

inves- tigate the effect of launching magnetostatic surface waves at different angles on a yttrium-iron- garnet (YIG) single crystal film . Many...propagation indeed could be achieved on a YIG thin film ring grown on a gadolinium-gallium- garnet (GGG) substrate (Sethares, 1975) (see Figure 1.1). The use of...thin films grown on a gadolinium-gallium- garnet substrate. The films were 27

Gadolinium chloride as a contrast agent for imaging wood composite components by magnetic resonance

Treesearch

Thomas L. Eberhardt; Chi-Leung So; Andrea Protti; Po-Wah So

2009-01-01

Although paramagnetic contrast agents have an established track record in medical uses of magnetic resonance imaging (MRI), only recently has a contrast agent been used for enhancing MRI images of solid wood specimens. Expanding on this concept, wood veneers were treated with a gadolinium-based contrast agent and used in a model system comprising three-ply plywood...

An Integrated Rare Earth Elements Supply Chain Strategy

DTIC Science & Technology

2011-02-24

iron boron magnets in Joint Direct Attack Munitions (JDAM) smart bombs; neodymium-yttrium- aluminum - garnet lasers and range finders in multiple weapon...components Europium 63 computer screens, fluorescent lights Gadolinium 64 magnetic applications, phosphors Terbium 65 phosphors, projection TV’s...Defense Stockpile report advised several production delays of weapons systems were caused by lanthanum, cerium, europium and gadolinium supply

Type of MRI contrast, tissue gadolinium, and fibrosis.

PubMed

Do, Catherine; Barnes, Jeffrey L; Tan, Chunyan; Wagner, Brent

2014-10-01

It has been presupposed that the thermodynamic stability constant (K(therm)) of gadolinium-based MRI chelates relate to the risk of precipitating nephrogenic systemic fibrosis. The present study compared low-K(therm) gadodiamide with high-K(therm) gadoteridol in cultured fibroblasts and rats with uninephrectomies. Gadolinium content was assessed using scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy in paraffin-embedded tissues. In vitro, fibroblasts demonstrated dose-dependent fibronectin generation, transforming growth factor-β production, and expression of activated myofibroblast stress fiber protein α-smooth muscle actin. There were negligible differences with respect to toxicity or proliferation between the two contrast agents. In the rodent model, gadodiamide treatment led to greater skin fibrosis and dermal cellularity than gadoteridol. In the kidney, both contrast agents led to proximal tubule vacuolization and increased fibronectin accumulation. Despite large detectable gadolinium signals in the spleen, skin, muscle, and liver from the gadodiamide-treated group, contrast-induced fibrosis appeared to be limited to the skin and kidney. These findings support the hypothesis that low-K(therm) chelates have a greater propensity to elicit nephrogenic systemic fibrosis and demonstrate that certain tissues are resistant to these effects.

Diagnostic value of three-dimensional magnetic resonance imaging of inner ear after intratympanic gadolinium injection, and clinical application of magnetic resonance imaging scoring system in patients with delayed endolymphatic hydrops.

PubMed

Gu, X; Fang, Z-M; Liu, Y; Lin, S-L; Han, B; Zhang, R; Chen, X

2014-01-01

Three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging of the inner ear after intratympanic injection of gadolinium, together with magnetic resonance imaging scoring of the perilymphatic space, were used to investigate the positive identification rate of hydrops and determine the technique's diagnostic value for delayed endolymphatic hydrops. Twenty-five patients with delayed endolymphatic hydrops underwent pure tone audiometry, bithermal caloric testing, vestibular-evoked myogenic potential testing and three-dimensional magnetic resonance imaging of the inner ear after bilateral intratympanic injection of gadolinium. The perilymphatic space of the scanned images was analysed to investigate the positive identification rate of endolymphatic hydrops. According to the magnetic resonance imaging scoring of the perilymphatic space and the diagnostic standard, 84 per cent of the patients examined had endolymphatic hydrops. In comparison, the positive identification rates for vestibular-evoked myogenic potential and bithermal caloric testing were 52 per cent and 72 per cent respectively. Three-dimensional magnetic resonance imaging after intratympanic injection of gadolinium is valuable in the diagnosis of delayed endolymphatic hydrops and its classification. The perilymphatic space scoring system improved the diagnostic accuracy of magnetic resonance imaging.

Gadolinium-enhanced inner ear magnetic resonance imaging for evaluation of delayed endolymphatic hydrops, including a bilateral case.

PubMed

Fukushima, Munehisa; Oya, Ryohei; Akazawa, Hitoshi; Tsuruta, Yukinori; Inohara, Hidenori

2016-01-01

The data suggests that gadolinium-enhanced inner ear MR imaging is useful for diagnosis of delayed endolymphatic hydrops (DEH) because it is independent of inner ear function, and the size of the affected endolymphatic space is clearly enlarged. This study was performed to semi-quantitatively evaluate the endolymphatic space in patients with all types of DEH using gadolinium-enhanced inner ear magnetic resonance (MR) imaging. Seven patients (age range = 21-77 years; five female, two male) with ipsilateral DEH (n = 5), contralateral DEH (n = 1), and bilateral DEH (n = 1). All patients underwent 3T MR imaging 4 h after intravenous injection of gadolinium. Software was used to determine the size of the endolymphatic space. Pure tone audiometry and caloric testing using an electronystagmogram were carried out. One side of the endolymphatic space was dominantly extended in patients with ipsilateral DEH, and both sides of the space were extended in patients with contralateral and bilateral DEH. In patients with ipsilateral DEH, the volume ratio of endolymph to vestibule was 2.5-4.3-times that in the unaffected ear. The volume ratio of endolymph to vestibule was nearly equal in patients with contralateral and bilateral DEH.

Characteristics of Gadolinium Oxide Nanoparticles Using Terahertz Spectroscopy

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

Lee, Dongkyu; Maeng, Inhee; Son, Joo-Hiuk

2009-04-19

The penetration property of the terahertz electromagnetic (THz) wave is relevant to its use. We used the THz wave spectroscopy system which easily penetrates some materials that do not contain water, e.g., plastic and ceramics. The system has been developed for several purposes, including measuring the properties of semiconductors and bio-materials, and detecting plastic bombs and ceramic knives at airports. It is also used for medical imaging systems, such as magnetic resonance imaging (MRI), at some research institutes. It can show not only the difference in amplitude, but also the difference of the phase of each point of sample. MRImore » technology usually uses contrast agents to enhance the quality of the image. Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), made with a heavy metal ion, is commonly used as a clinical MRI contrast agent. Gadolinium oxide (Gd{sub 2}O{sub 3}) nanoparticle is a new contrast agent. It serves to equip the core of each particle with antibodies or ligands. It can freely circulate in blood vessels without amassing in the liver or lungs. This study shows the characteristics of gadolinium oxide nanoparticles to further advance terahertz medical imaging.« less

Gadolinium based contrast agents in current practice: Risks of accumulation and toxicity in patients with normal renal function

PubMed Central

Ranga, Anju; Agarwal, Yatish; Garg, Kanika J

2017-01-01

Despite being decked as the most prized compounds in the nugget box of contrast agents for clinical radiologists, and carrying an indisputable tag of safety of the US Food and Drug Administration for close to three decades, all may not be seemingly well with the family of gadolinium compounds. If the first signs of violations of primum non nocere in relation to gadolinium-based contrast agents (GBCAs) appeared in the millennium year with the first published report of skin fibrosis in patients with compromised renal function, the causal relationship between the development of nephrogenic systemic fibrosis (NSF) and GBCAs, first proposed by two European groups in 2006, further precluded their use in renocompromised patients. The toxicity, pharmacokinetics, and pharmacodynamics of GBCAs, however, has come under hawk-eyed scrutiny with recent reports that gadolinium tends to deposit cumulatively in the brain of patients with normal hepatobiliary function and intact blood–brain barrier. While the jury on the long-term hazard significance of this critical scientific finding is still out, the use of GBCAs must be guided by due clinical diligence, avoidance of repeated doses, and preferring GBCAs with the best safety profiles. PMID:28744073

Gadolinium enhanced cardiovascular magnetic resonance in Anderson-Fabry disease. Evidence for a disease specific abnormality of the myocardial interstitium.

PubMed

Moon, James C C; Sachdev, Bhavesh; Elkington, Andrew G; McKenna, William J; Mehta, Atul; Pennell, Dudley J; Leed, Philip J; Elliott, Perry M

2003-12-01

Anderson-Fabry Disease (AFD), an X-linked disorder of sphingolipid metabolism, is a cause of idiopathic left ventricular hypertrophy but the mechanism of hypertrophy is poorly understood. Gadolinium enhanced cardiovascular magnetic resonance can detect focal myocardial fibrosis. We hypothesised that hyperenhancement would be present in AFD. Eighteen males (mean 43+/-14 years) and eight female heterozygotes (mean 48+/-12 years) with AFD underwent cine and late gadolinium cardiovascular magnetic resonance. Nine male (50%) had myocardial hyperenhancement ranging from 3.4% to 20.6% (mean 7.7+/-5.7%) of total myocardium; in males, percentage hyperenhancement related to LV mass index (r=0.78, P=0.0002) but not to ejection fraction or left ventricular volumes. Lesser hyperenhancement was also found in four (50%) heterozygous females (mean 4.6%). In 12 (92%) patients with abnormal gadolinium uptake, hyperenhancement occurred in the basal infero-lateral wall where, unlike myocardial infarction, it was not sub-endocardial. In two male patients with severe LVH (left ventricular hypertrophy) and systolic impairment there was additional hyperenhancement in other myocardial segments. These observations suggests that myocardial fibrosis occurs in AFD and may contribute to the hypertrophy and the natural history of the disease.

Application of an oscillation-type linear cadmium telluride detector to enhanced gadolinium K-edge computed tomography

NASA Astrophysics Data System (ADS)

Matsukiyo, Hiroshi; Sato, Eiichi; Hagiwara, Osahiko; Abudurexiti, Abulajiang; Osawa, Akihiro; Enomoto, Toshiyuki; Watanabe, Manabu; Nagao, Jiro; Sato, Shigehiro; Ogawa, Akira; Onagawa, Jun

2011-03-01

A linear cadmium telluride (CdTe) detector is useful for carrying out energy-discrimination X-ray imaging, including computed tomography (CT). To perform enhanced gadolinium K-edge CT, we used an oscillation-type linear CdTe detector with an energy resolution of 1.2 keV. CT is performed by repeating the linear scan and the rotation of an object. Penetrating X-ray photons from the object are detected by the CdTe detector, and event signals of X-ray photons are produced using charge-sensitive and shaping amplifiers. Both the photon energy and the energy width are selected using a multichannel analyzer, and the number of photons is counted by a counter card. In energy-discrimination CT, tube voltage and current were 80 kV and 20 μA, respectively, and X-ray intensity was 1.55 μGy/s at 1.0 m from the source at a tube voltage of 80 kV. Demonstration of enhanced gadolinium K-edge X-ray CT was carried out by selecting photons with energies just beyond gadolinium K-edge energy of 50.3 keV.

Investigation of suspected Guillain-Barre syndrome in childhood: what is the role for gadolinium enhanced magnetic resonance imaging of the spine?

PubMed

Smith, Nicholas; Pereira, John; Grattan-Smith, Padraic

2014-10-01

To review the role of gadolinium-enhanced magnetic resonance imaging of the spine in the diagnosis of paediatric Guillain-Barre syndrome and compare it with nerve conduction studies and cerebrospinal fluid analysis. A retrospective review of investigations undertaken in children admitted to our institution with acute Guillain-Barre syndrome over a 10-year period was performed. Seven of eight children (88%) displayed post-gadolinium nerve root enhancement consistent with Guillain-Barre syndrome. This compared with supportive nerve conduction studies in 21/24 children (88%) and cerebrospinal fluid protein analysis consistent with the diagnosis in 16/20 children (80%). Nerve conduction studies are the recognised 'gold standard' technique for confirming a clinical diagnosis of Guillain-Barre syndrome. In this study, a high positive rate was demonstrated. While more experience is necessary, this study and the literature support gadolinium enhanced magnetic resonance imaging of the spine as a valuable, although not necessarily superior, investigation in the diagnosis of Guillain-Barre syndrome. It may be of particular benefit when specialist neurophysiology expertise is unavailable. © 2010 The Authors. Journal compilation © 2010 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

Axitinib in Treating Patients With Melanoma That is Metastatic or Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-05-08

Extraocular Extension Melanoma; Metastatic Intraocular Melanoma; Recurrent Intraocular Melanoma; Recurrent Melanoma; Stage IIIA Intraocular Melanoma; Stage IIIA Melanoma; Stage IIIB Intraocular Melanoma; Stage IIIB Melanoma; Stage IIIC Intraocular Melanoma; Stage IIIC Melanoma; Stage IV Intraocular Melanoma; Stage IV Melanoma

Nutrients removal from undiluted cattle farm wastewater by the two-stage process of microalgae-based wastewater treatment.

PubMed

Lv, Junping; Liu, Yang; Feng, Jia; Liu, Qi; Nan, Fangru; Xie, Shulian

2018-05-24

Chlorella vulgaris was selected from five freshwater microalgal strains of Chlorophyta, and showed a good potential in nutrients removal from undiluted cattle farm wastewater. By the end of treatment, 62.30%, 81.16% and 85.29% of chemical oxygen demand (COD), ammonium (NH 4 + -N) and total phosphorus (TP) were removed. Then two two-stage processes were established to enhance nutrients removal efficiency for meeting the discharge standards of China. The process A was the biological treatment via C. vulgaris followed by the biological treatment via C. vulgaris, and the process B was the biological treatment via C. vulgaris followed by the activated carbon adsorption. After 3-5 d of treatment of wastewater via the two processes, the nutrients removal efficiency of COD, NH 4 + -N and TP were 91.24%-92.17%, 83.16%-94.27% and 90.98%-94.41%, respectively. The integrated two-stage process could strengthen nutrients removal efficiency from undiluted cattle farm wastewater with high organic substance and nitrogen concentration. Copyright © 2018 Elsevier Ltd. All rights reserved.

Center removal amount control of magnetorheological finishing process by spiral polishing way

NASA Astrophysics Data System (ADS)

Wang, Yajun; He, Jianguo; Ji, Fang; Huang, Wen; Xiao, Hong; Luo, Qing; Zheng, Yongcheng

2010-10-01

Spiral polishing is a traditional process of computer-controlled optical surfacing. However, the additional polishing amount is great and the center polishing amount is difficult to control. At first, a simplified mathematics model is presented for magnetorheological finishing, which indicates that the center polishing amount and additional polishing amount are proportional to the length and peak value of magnetorheological finishing influence function, and are inversely proportional to pitch and rotation rate of spiral track, and the center polishing amount is much bigger than average polishing amount. Secondly, the relationships of "tool feed way and center polishing amount", "spiral pitch and calculation accuracy of influence matrix for dwell time function solution", "spiral pitch and center polishing amount" and "peak removal rate, dimensions of removal function and center removal amount" are studied by numerical computation by Archimedes spiral path. It shows that the center polishing amount is much bigger in feed stage than that in backhaul stage when the head of influence function is towards workpiece edge in feeding; and the bigger pitch, the bigger calculation error of influence matrix elements; and the bigger pitch, the smaller center polishing amount, and the smaller peak removal rate and dimensions of removal function, the smaller center removal amount. At last, the polishing results are given, which indicates that the center polishing amount is acceptable with a suitable polishing amount rate of feed stage and backhaul stage, and with a suitable spiral pitch during magnetorheological finishing procedure by spiral motion way.

Automated segmentation of myocardial scar in late enhancement MRI using combined intensity and spatial information.

PubMed

Tao, Qian; Milles, Julien; Zeppenfeld, Katja; Lamb, Hildo J; Bax, Jeroen J; Reiber, Johan H C; van der Geest, Rob J

2010-08-01

Accurate assessment of the size and distribution of a myocardial infarction (MI) from late gadolinium enhancement (LGE) MRI is of significant prognostic value for postinfarction patients. In this paper, an automatic MI identification method combining both intensity and spatial information is presented in a clear framework of (i) initialization, (ii) false acceptance removal, and (iii) false rejection removal. The method was validated on LGE MR images of 20 chronic postinfarction patients, using manually traced MI contours from two independent observers as reference. Good agreement was observed between automatic and manual MI identification. Validation results showed that the average Dice indices, which describe the percentage of overlap between two regions, were 0.83 +/- 0.07 and 0.79 +/- 0.08 between the automatic identification and the manual tracing from observer 1 and observer 2, and the errors in estimated infarct percentage were 0.0 +/- 1.9% and 3.8 +/- 4.7% compared with observer 1 and observer 2. The difference between the automatic method and manual tracing is in the order of interobserver variation. In conclusion, the developed automatic method is accurate and robust in MI delineation, providing an objective tool for quantitative assessment of MI in LGE MR imaging.

Purification of lanthanides for double beta decay experiments

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

Polischuk, O. G.; Barabash, A. S.; Belli, P.

2013-08-08

There are several potentially double beta active isotopes among the lanthanide elements. However, even high purity grade lanthanide compounds contain {sup 238}U, {sup 226}Ra and {sup 232,228}Th typically on the level of ∼ (0.1 - 1) Bq/kg. The liquid-liquid extraction technique was used to remove traces of U, Ra and Th from CeO{sub 2}, Nd{sub 2}O{sub 3} and Gd{sub 2}O{sub 3}. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe γ spectrometry at the underground Gran Sasso National Laboratories of the INFN (Italy). After the purification the radioactive contamination of gadolinium oxidemore » by Ra and Th was decreased at least one order of magnitude. The efficiency of the approach to purify cerium oxide from Ra was on same level, while the radioactive contamination of neodymium sample before and after the purification is below the sensitivity of analytical methods. The purification method is much less efficient for chemically very similar radioactive elements like lanthanum, lutetium and actinium. R and D of the methods to remove the pollutions with improved efficiency is in progress.« less

Effect of impurities and post-experimental purification in SAD phasing with serial femtosecond crystallography data.

PubMed

Zhang, Tao; Gu, Yuanxin; Fan, Haifu

2016-06-01

In serial crystallography (SX) with either an X-ray free-electron laser (XFEL) or synchrotron radiation as the light source, huge numbers of micrometre-sized crystals are used in diffraction data collection. For a SAD experiment using a derivative with introduced heavy atoms, it is difficult to completely exclude crystals of the native protein from the sample. In this paper, simulations were performed to study how the inclusion of native crystals in the derivative sample could affect the result of SAD phasing and how the post-experimental purification proposed by Zhang et al. [(2015), Acta Cryst. D71, 2513-2518] could be used to remove the impurities. A gadolinium derivative of lysozyme and the corresponding native protein were used in the test. Serial femtosecond crystallography (SFX) diffraction snapshots were generated by CrystFEL. SHELXC/D, Phaser, DM, ARP/wARP and REFMAC were used for automatic structure solution. It is shown that a small amount of impurities (snapshots from native crystals) in the set of derivative snapshots can strongly affect the SAD phasing results. On the other hand, post-experimental purification can efficiently remove the impurities, leading to results similar to those from a pure sample.

Ant-diaspore interactions during secondary succession in the Atlantic forest of Brazil.

PubMed

Zwiener, Victor P; Bihn, Jochen H; Marques, Márcia C M

2012-06-01

Animal-plant interactions are important for the recovery of diversity and processes in secondary forests, which increasingly dominate the tropical landscape. We used a combination of observational and experimental approaches to study the interactions of ants with diaspores across a successional gradient of forests in Southern Brazil, from August 2007 to April 2008. In addition to diaspore removal rates, we assessed the species richness, diversity and behaviour of ants interacting with diaspores, in three replicated sites of four successional stages of forests. We recorded 22 ant species interacting with diaspores (an estimated 15% of the total species pool in the region). Species richness and diversity did not differ among successional stages but the behaviour of ants towards diaspores changed with the age of secondary forests. In old successional stages the removal of entire diaspores was more common than in young successional stages of forests. Concordantly, diaspore removal rates were lowest in the youngest successional stage of secondary forests and increased with the age of forests. These results indicate that ant-diaspore interactions in secondary forests are disturbed and lower removal rates in secondary forests are likely to constrain the recruitment of plant populations during secondary succession.

Correlation Among Soil Enzyme Activities, Root Enzyme Activities, and Contaminant Removal in Two-Stage In Situ Constructed Wetlands Purifying Domestic Wastewater.

PubMed

Ni, Lixiao; Xu, Jiajun; Chu, Xianglin; Li, Shiyin; Wang, Peifang; Li, Yiping; Li, Yong; Zhu, Liang; Wang, Chao

2016-07-01

Two-stage in situ wetlands (two vertical flow constructed wetlands in parallel and a horizontal flow constructed wetland) were constructed for studying domestic wastewater purification and the correlations between contaminant removal and plant and soil enzyme activities. Results indicated the removal efficiency of NH4 (+) and NO3 (-) were significantly correlated with both urease and protease activity, and the removal of total phosphorus was significantly correlated with phosphatase activity. Chemical oxygen demand removal was not correlated with enzyme activity in constructed wetlands. Plant root enzyme (urease, phosphatase, protease and cellulose) activity correlation was apparent with all contaminant removal in the two vertical flow constructed wetlands. However, the correlation between the plant root enzyme activity and contaminant removal was poor in horizontal flow constructed wetlands. Results indicated that plant roots clearly played a role in the removal of contaminants.

Investigation of decolorization of textile wastewater in an anaerobic/aerobic biological activated carbon system (A/A BAC).

PubMed

Pasukphun, N; Vinitnantharat, S; Gheewala, S

2010-04-01

The aim of this study is to investigate the decolorization in anaerobic/aerobic biological activated carbon (A/A BAC) system. The experiment was divided into 2 stages; stage I is batch test for preliminary study of dye removal equilibrium time. The preliminary experiment (stage I) provided the optimal data for experimental design of A/A BAC system in SBR (stage II). Stage II is A/A BAC system imitated Sequencing Batch Reactor (SBR) which consist of 5 main periods; fill, react, settle, draw and idle. React period include anaerobic phase followed by aerobic phase. The BAC main media; Granular Activated Carbon (GAC), Mixed Cultures (MC) and Biological Activated Carbon (BAC) were used for dye and organic substances removal in three different solutions; Desizing Agent Solution (DAS), dye Solution (DS) and Synthetic Textile Wastewater (STW). Results indicate that GAC adsorption plays role in dye removal followed by BAC and MC activities, respectively. In the presence desizing agent, decolorization by MC was improved because desizing agent acts as co-substrates for microorganisms. It was found that 50% of dye removal efficiency was achieved in Fill period by MC. GC/MS analysis was used to identify dye intermediate from decolorization. Dye intermediate containing amine group was found in the solution and on BAC surfaces. The results demonstrated that combination of MC and BAC in the system promotes decolorization and dye intermediate removal. In order to improve dye removal efficiency in an A/A BAC system, replacement of virgin GAC, sufficient co-substrates supply and the appropriate anaerobic: aerobic period should be considered.

Gemcitabine Hydrochloride, Docetaxel, and Radiation Therapy in Treating Patients With Uterine Sarcoma That Has Been Removed By Surgery

ClinicalTrials.gov

2015-01-16

Stage IA Uterine Sarcoma; Stage IB Uterine Sarcoma; Stage IC Uterine Sarcoma; Stage IIA Uterine Sarcoma; Stage IIB Uterine Sarcoma; Stage IIIA Uterine Sarcoma; Stage IIIB Uterine Sarcoma; Stage IIIC Uterine Sarcoma; Stage IVA Uterine Sarcoma; Stage IVB Uterine Sarcoma; Uterine Corpus Leiomyosarcoma

Biocompatible Polyhydroxyethylaspartamide-based Micelles with Gadolinium for MRI Contrast Agents

NASA Astrophysics Data System (ADS)

Jeong, Sang Young; Kim, Hyo Jeong; Kwak, Byung-Kook; Lee, Ha-Young; Seong, Hasoo; Shin, Byung Cheol; Yuk, Soon Hong; Hwang, Sung-Joo; Cho, Sun Hang

2010-12-01

Biocompatible poly-[ N-(2-hydroxyethyl)- d, l-aspartamide]-methoxypoly(ethyleneglycol)-hexadecylamine (PHEA-mPEG-C16) conjugated with 1,4,7,10-tetraazacyclododecan-1,4,7,10-tetraacetic acid-gadolinium (DOTA-Gd) via ethylenediamine (ED) was synthesized as a magnetic resonance imaging (MRI) contrast agent. Amphiphilic PHEA-mPEG-C16-ED-DOTA-Gd forms micelle in aqueous solution. All the synthesized materials were characterized by proton nuclear magnetic resonance (1H NMR). Micelle size and shape were examined by dynamic light scattering (DLS) and atomic force microscopy (AFM). Micelles with PHEA-mPEG-C16-ED-DOTA-Gd showed higher relaxivities than the commercially available gadolinium contrast agent. Moreover, the signal intensity of a rabbit liver was effectively increased after intravenous injection of PHEA-mPEG-C16-ED-DOTA-Gd.

Renal function, nephrogenic systemic fibrosis and other adverse reactions associated with gadolinium-based contrast media.

PubMed

Canga, Ana; Kislikova, Maria; Martínez-Gálvez, María; Arias, Mercedes; Fraga-Rivas, Patricia; Poyatos, Cecilio; de Francisco, Angel L M

2014-01-01

Nephrogenic systemic fibrosis is a fibrosing disorder that affects patients with impaired renal function and is associated with the administration of gadolinium-based contrast media used in MRI. Despite being in a group of drugs that were considered safe, report about this potentially serious adverse reaction was a turning point in the administration guidelines of these contrast media. There has been an attempt to establish safety parameters to identify patients with risk factors of renal failure. The close pharmacovigilance and strict observation of current regulations, with special attention being paid to the value of glomerular filtration, have reduced the published cases involving the use of gadolinium-based contrast media. In a meeting between radiologists and nephrologists we reviewed the most relevant aspects currently and recommendations for its prevention.

The performance of hafnium and gadolinium self powered neutron detectors in the TREAT reactor

NASA Astrophysics Data System (ADS)

Imel, G. R.; Hart, P. R.

1996-05-01

The use of gadolinium and hafnium self powered neutron detectors in a transient reactor is described in this paper. The detectors were calibrated to the fission rate of U-235 using calibrated fission chambers; the calibration factors were tested in two reactors in steady state and found to be consistent. Calibration of the detectors in transient reactor conditions was done by using uranium wires that were analyzed by radiochemistry techniques to determine total fissions during the transient. This was correlated to the time-integrated current of the detectors during the transient. A temperature correction factor was derived to account for self-shielding effects in the hafnium and gadolinium detectors. The dynamic response of the detectors under transient conditions was studied, and found to be excellent.

Electron magnetic resonance investigation of gadolinium diffusion in zircon powders

NASA Astrophysics Data System (ADS)

de Biasi, R. S.; Grillo, M. L. N.

2011-11-01

The electron magnetic resonance (EMR) technique was used to investigate the diffusion of gadolinium in zircon (ZrSiO4) powders. The EMR absorption intensity was measured for several annealing times and three different temperatures of isothermal annealing: 1273, 1323 and 1373 K. The activation energy for diffusion, calculated from the experimental data using a theoretical model based on the Fick equation, was found to be EA=506±5 kJ mol-1. This value is close to the ones for the diffusion of Gd in UO2 and CeO2, but much larger than for the diffusion of gadolinium in a compound with the same crystal structure as zircon, YVO4. This is attributed to a difference in the relative sizes of the ions involved in the diffusion process.

Current status of SK-Gd project and EGADS

NASA Astrophysics Data System (ADS)

Xu, Chenyuan; Super-Kamiokande Collaboration

2016-05-01

Supernova Relic Neutrino (SRN) has not been observed yet because of its low event rate and high background. By adding gadolinium into water Cherenkov detector, inverse beta decay will have two signals, the prompt one is positron signal and the delayed one is a ~8 MeV gamma cascade from neutron capture on gadolinium. By this way, background for SRN can be largely reduced by detecting prompt and delayed signals coincidently, and Super-K will also have the ability to distinguish neutrino and anti-neutrino. SK-Gd is a R&D project proposed to dissolve gadolinium into Super-K. As a part of it, EGADS, a 200 ton water Cherenkov detector was built in Kamioka mine. Current status of SK-Gd project and the physics work being performed in EGADS will be presented here.

Graphene oxide-gadolinium (III) oxide nanoparticle composite: a novel MR contrast agent with high longitudinal and transverse relaxivity

NASA Astrophysics Data System (ADS)

Venkatesha, N.; Poojar, Pavan; Geethanath, Sairam; Srivastava, Chandan

2014-12-01

Production of bio-compatible contrast agent materials to enhance the sensitivity of the magnetic resonance imaging (MRI) technique is a highly active area in MRI related research. This work illustrates the potential of a new material: graphene oxide-gadolinium (III) oxide nanoparticle (GO-Gd2O3) composite in yielding both transverse (16.3 mM-1 s-1) and longitudinal relaxivity (40 mM-1 s-1) values which are significantly higher than the proton relaxivity values achieved using the gadolinium based contrast agents currently used in MRI. Such high proton relaxivity values can facilitate low dosage of GO-Gd2O3 composite for obtaining both T1 and T2 weighted high signal-to-noise ratio images in MRI.

Suppression of Rabbit VX‐2 Subcutaneous Tumor Growth by Gadolinium Neutron Capture Therapy

PubMed Central

Tokita, Nobuhiko; Tokuuye, Koichi; Satoh, Michinao; Churei, Hisahiko; Pechoux, Cécile Le; Kobayashi, Tooru; Kanda, Keiji

1993-01-01

VX‐2 tumors growing in hind legs of New Zealand White rabbits (n=4) were exposed to thermal neutrons for 40 min (2.1 × 1012 neutrons cm−2) while one of two hind leg tumors of each rabbit was infused continuously with meglumine gadopentetate through a branch of the left femoral artery. The contralateral (uninfused) tumors served as controls. Although no differential distribution of gadolinium was achieved between the tumor and its adjacent normal tissue, the gadolinium concentration in the infused tumor was approximately 5–6 fold higher than that in the contralateral tumor. Growth of gadolinium‐infused tumors was significantly inhibited compared to that of control tumors (P<0.05) between the 16th and 23rd days after treatment. PMID:8407547

Gadolinium concentration analysis in brain phantom by X-ray fluorescence.

PubMed

Almalki, Musaed; Majid, Samir Abdul; Butler, Philip H; Reinisch, Lou

2010-06-01

We have measured the X-ray fluorescence from gadolinium as a function of concentration and position in tumors of different sizes and shapes in a head phantom. The gadolinium fluorescence was excited with a 36 GBq Am-241 source. The fluorescence signal was detected with a CdTe detector and a multi-channel analyzer. The fluorescence peak was clearly separated from the scattered X-rays. Concentrations of 5.62-78.63 mg/ml of Gd ion were used in 1, 2, and 3 cm diameter spherical tumors and a 2x4 cm oblate spheroid tumor. The data show trends approaching saturation for the highest concentrations, probably due to reabsorption in the tumor. A comparison of X-ray photographic imaging and densitometer measurements to determine concentration is also presented.

Dramatic impact of the giant local magnetic fields on spin-dependent recombination processes in gadolinium based garnets

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

Romanov, N. G., E-mail: nikolai.romanov@mail.ioffe.ru; Tolmachev, D. O.; Gurin, A. S.

2015-06-29

A giant magnetic field effect on spin-dependent recombination of the radiation-induced defects has been found in cerium doped gadolinium based garnet crystals and ceramics, promising materials for scintillator applications. A sharp and strong increase in the afterglow intensity stimulated by external magnetic field and an evidence of the magnetic field memory have been discovered. The effect was ascribed to huge Gd-induced internal magnetic fields, which suppress the recombination, and cross-relaxation with Gd{sup 3+} ions leading to reorientation of the spins of the electron and hole centers. Thus, the spin system of radiation-induced defects in gadolinium garnet based scintillator materials wasmore » shown to accumulate significant energy which can be released in external magnetic fields.« less

Flotation of metal-loaded clay anion exchangers. Part II: the case of arsenates.

PubMed

Lazaridis, N K; Hourzemanoglou, A; Matis, K A

2002-04-01

Hydrotalcite-like materials, or otherwise termed layered double hydroxides, are clays with an ability to remove anions. As they usually are in powder form, these sorbents often present appreciable problems in the solid/liquid separation process following the sorption stage. Sorptive flotation of metal-loaded particles was investigated in this paper, as an alternative two-stage process. In the sorption process, satisfactory removals of arsenic(V) were obtained onto synthetic hydrotalcite particles from water. The effect of some parameters, like the solution ionic strength, concentrations, temperature, etc. was examined. During the second stage of the process, hydrotalcite fine particles were removed from the liquid phase by dispersed-air flotation; various surfactants were tested in relation to the ionic strength of the solution. The combined process of sorptive flotation provides promising results for arsenic removal.

76 FR 42610 - Airworthiness Directives; Turbomeca Arriel 1 Series Turboshaft Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-19

... products listed above. The existing AD currently requires removing from service certain gas generator..., whichever occurs later. That AD also requires removing from service certain gas generator second stage... affected discs. We are proposing this AD to prevent failure of the gas generator second stage turbine disc...

Erlotinib Hydrochloride in Treating Patients With Pancreatic Cancer That Can Be Removed by Surgery

ClinicalTrials.gov

2014-10-07

Intraductal Papillary Mucinous Neoplasm of the Pancreas; Recurrent Pancreatic Cancer; Stage IA Pancreatic Cancer; Stage IB Pancreatic Cancer; Stage IIA Pancreatic Cancer; Stage IIB Pancreatic Cancer; Stage III Pancreatic Cancer

Sorafenib Tosylate in Treating Patients With Liver Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2017-06-30

Advanced Adult Hepatocellular Carcinoma; Localized Non-Resectable Adult Hepatocellular Carcinoma; Stage III Childhood Hepatocellular Carcinoma; Stage IIIA Hepatocellular Carcinoma; Stage IIIB Hepatocellular Carcinoma; Stage IIIC Hepatocellular Carcinoma; Stage IV Childhood Hepatocellular Carcinoma; Stage IVA Hepatocellular Carcinoma; Stage IVB Hepatocellular Carcinoma

Quantitative assessment of hepatic fibrosis in chronic hepatitis B and C: T1 mapping on Gd-EOB-DTPA-enhanced liver magnetic resonance imaging.

PubMed

Pan, Shen; Wang, Xiao-Qi; Guo, Qi-Yong

2018-05-14

To assess the accuracy of Look-Locker on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for staging liver fibrosis in chronic hepatitis B/C (CHB/C). We prospectively included 109 patients with CHB or CHC who underwent a 3.0-Tesla MRI examination, including T1-weighted and Look-Locker sequences for T1 mapping. Hepatocyte fractions (HeF) and relaxation time reduction rate (RE) were measured for staging liver fibrosis. A receiver operating characteristic analysis using the area under the receiver operating characteristic curve (AUC) was used to compare the diagnostic performance in predicting liver fibrosis between HeF and RE. A total of 73 patients had both pathological results and MRI information. The number of patients in each fibrosis stage was evaluated semiquantitatively according to the METAVIR scoring system: F0, n = 23 (31.5%); F1, n = 19 (26.0%); F2, n = 13 (17.8%); F3, n = 6 (8.2%), and F4, n = 12 (16.4%). HeF by EOB enhancement imaging was significantly correlated with fibrosis stage ( r = -0.808, P < 0.05). AUC values for diagnosis of any (≥ F1), significant (≥ F2) or advanced (≥ F3) fibrosis, and cirrhosis (F4) using HeF were 0.837 (0.733-0.913), 0.890 (0.795-0.951), 0.957 (0.881-0.990), and 0.957 (0.882-0.991), respectively. HeF measurement was more accurate than use of RE in establishing liver fibrosis staging, suggesting that calculation of HeF is a superior noninvasive liver fibrosis staging method. A T1 mapping-based HeF method is an efficient diagnostic tool for the staging of liver fibrosis.

Switching of the polarization of ferroelectric-ferroelastic gadolinium molybdate in a magnetic field

NASA Astrophysics Data System (ADS)

Yakushkin, E. D.

2017-10-01

A change in the character of the electric switching of polydomain ferroelectric-ferroelastic gadolinium molybdate in an external magnetic field has been detected. This change has been attributed to a magnetically stimulated increase in the pinning of domain walls. Under certain conditions, the loop of switchable polarization is degenerated into an ellipse characteristic of a linear insulator with leakage current.

Fuel bundle design for enhanced usage of plutonium fuel

DOEpatents

Reese, Anthony P.; Stachowski, Russell E.

1995-01-01

A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced.

Fuel bundle design for enhanced usage of plutonium fuel

DOEpatents

Reese, A.P.; Stachowski, R.E.

1995-08-08

A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced. 10 figs.

Thermal energy harvesting and solar energy conversion utilizing carbon-based nanomaterials

NASA Astrophysics Data System (ADS)

McCarthy, Patrick T.

This dissertation provides details of carbon-based nanomaterial fabrication for applications in energy harvesting and generation. As energy demands increase, and concerns about mankind's environmental impact increase, alternative methods of generating energy will be widely researched. Carbon-based nanomaterials may be effective in such applications as their fabrication is often inexpensive and they have highly desirable electrical, mechanical, and thermal properties. Synthesis and characterization of carbon nanotube thermal interfaces on gadolinium foils is described herein. Total thermal interface resistances of carbon nanotube coated gadolinium were measured using a one-dimensional reference calorimeter technique, and the effect of hydrogen embrittlement on the magnetic properties of gadolinium foils is discussed. The samples generated in this study were consistently measured with reduced total thermal interface resistances of 55-70% compared to bare gadolinium. Characterization of gadolinium foils in a cooling device called a magneto thermoelectric generator was also performed. A gadolinium shuttle drives the device as it transitions between ferromagnetic and paramagnetic states. Reduced interface resistances from the carbon nanotube arrays led to increased shuttle frequency and effective heat transfer coefficients. Detailed theoretical derivations for electron emission during thermal and photo-excitation are provided for both three-dimensional and two-dimensional materials. The derived theories were fitted to experimental data from variable temperature photoemission studies of potassium-intercalated graphitic nanopetals. A work function reduction from approximately 4.5 eV to 2 -- 3 eV resulted from potassium intercalation and adsorption. While changes in the electron energy distribution shape and intensity were significant within 310 -- 680 K, potassium-intercalated graphitic petals demonstrate very high thermal stability after heating to nearly 1000 K. Boron nitride modification of the nanopetals was performed in an effort to minimize deintercalation of potassium from the nanopetal lattice and while multiple work functions were present within the electron energy distribution, massive reductions in emission intensity took place above 580 K. Finally, a device for measuring the current density during photoemission was also developed and photoemission induced by a solar simulator at room temperature produced currents on the order of 1 nA/cm 2 resulting in a quantum efficiency of approximately 8.0x10 --8 electrons emitted per photon of illumination.

Gadolinium-148 and other spallation production cross section measurements for accelerator target facilities

NASA Astrophysics Data System (ADS)

Kelley, Karen Corzine

At the Los Alamos Neutron Science Center accelerator complex, protons are accelerated to 800 MeV and directed to two tungsten targets, Target 4 at the Weapons Neutron Research facility and the 1L target at the Lujan Center. The Department of Energy requires hazard classification analyses to be performed on these targets and places limits on certain radionuclide inventories in the targets to avoid characterizing the facilities as "nuclear facilities." Gadolinium-148 is a radionuclide created from the spallation of tungsten. Allowed isotopic inventories are particularly low for this isotope because it is an alpha-particle emitter with a 75-year half-life. The activity level of Gadolinium-148 is low, but it encompasses almost two-thirds of the total dose burden for the two tungsten targets based on present yield estimates. From a hazard classification standpoint, this severely limits the lifetime of these tungsten targets. The cross section is not well-established experimentally and this is the motivation for measuring the Gadolinium-148 production cross section from tungsten. In a series of experiments at the Weapons Neutron Research facility, Gadolinium-148 production was measured for 600- and 800-MeV protons on tungsten, tantalum, and gold. These experiments used 3 mum thin tungsten, tantalum, and gold foils and 10 mum thin aluminum activation foils. In addition, spallation yields were determined for many short-lived and long-lived spallation products with these foils using gamma and alpha spectroscopy and compared with predictions of the Los Alamos National Laboratory codes CEM2k+GEM2 and MCNPX. The cumulative Gadolinium-148 production cross section measured from tantalum, tungsten, and gold for incident 600-MeV protons were 15.2 +/- 4.0, 8.31 +/- 0.92, and 0.591 +/- 0.155, respectively. The average production cross sections measured at 800 MeV were 28.6 +/- 3.5, 19.4 +/- 1.8, and 3.69 +/- 0.50 for tantalum, tungsten, and gold, respectively. These cumulative measurements compared best with Bertini and were within a factor of two to three of CEM2k+GEM2.

Stereotactic Body Radiation Therapy and Transarterial Chemoembolization in Treating Patients With Liver Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-03-01

Child-Pugh Class A; Child-Pugh Class B; Stage IIIA Hepatocellular Carcinoma; Stage IIIB Hepatocellular Carcinoma; Stage IIIC Hepatocellular Carcinoma; Stage IVA Hepatocellular Carcinoma; Stage IVB Hepatocellular Carcinoma

Producing desulfurized biogas through removal of sulfate in the first-stage of a two-stage anaerobic digestion.

PubMed

Yun, Yeo-Myeong; Sung, Shihwu; Shin, Hang-Sik; Han, Jong-In; Kim, Hyun-Woo; Kim, Dong-Hoon

2017-05-01

In the present work, a two-stage anaerobic digestion system (TSADS) was newly designed to produce biogas with a greatly reduced H 2 S content. The role of first (sulfidogenic)-stage digester was not only acidogenesis but also sulfidogenesis (sulfate reduction to H 2 S), which would minimize the input of H 2 S-producing source in the followed second (methanogenic)-stage digester. For the coexistence of acidogens and sulfate reducing bacteria (SRB) in the sulfidogenic-stage digester, it was found that pH played a crucial role. The acidogenic activity was not affected within a pH range of 4.5-6.0, while it was important to maintain a pH at 5.5 to achieve a sulfate removal efficiency over 70%. The highest sulfate removal attained was 78% at a hydraulic retention time (HRT) of 5 h at pH 5.5 ± 0.1. The H 2 S content in the biogas produced in the conventional single-stage digester (SSAD), used as a control, reached 1,650 ± 25 ppm v . In contrast, the biogas produced in the methanogenic-stage digester of the developed process had an H 2 S content of 200 ± 15 ppm v . Microbial analysis, done by the next generation sequencing technique, clearly showed the changes in community under different operating conditions. Desulfovibrio bastinii (4.9%) played a key role in sulfate removal in the sulfidogenic-stage of the TSADS owing to its characteristics of a short doubling time and growth in an acidic environment. Biotechnol. Bioeng. 2017;114: 970-979. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Fulvestrant and Palbociclib in Treating Older Patients With Hormone Responsive Breast Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2016-09-21

Estrogen Receptor and/or Progesterone Receptor Positive; HER2/Neu Negative; Stage IA Breast Cancer; Stage IB Breast Cancer; Stage IIA Breast Cancer; Stage IIB Breast Cancer; Stage IIIA Breast Cancer; Stage IIIB Breast Cancer; Stage IIIC Breast Cancer

Inter-stage thermophilic aerobic digestion may increase organic matter removal from wastewater sludge without decreasing biogas production.

PubMed

Hafner, Sasha D; Madsen, Johan T; Pedersen, Johanna M; Rennuit, Charlotte

2018-02-01

Combining aerobic and anaerobic digestion in a two-stage system can improve the degradation of wastewater sludge over the use of either technology alone. But use of aerobic digestion as a pre-treatment before anaerobic digestion generally reduces methane production due to loss of substrate through oxidation. An inter-stage configuration may avoid this reduction in methane production. Here, we evaluated the use of thermophilic aerobic digestion (TAD) as an inter-stage treatment for wastewater sludge using laboratory-scale semi-continuous reactors. A single anaerobic digester was compared to an inter-stage system, where a thermophilic aerobic digester (55 °C) was used between two mesophilic anaerobic digesters (37 °C). Both systems had retention times of approximately 30 days, and the comparison was based on measurements made over 97 days. Results showed that the inter-stage system provided better sludge destruction (52% volatile solids (VS) removal vs. 40% for the single-stage system, 44% chemical oxygen demand (COD) removal vs. 34%) without a decrease in total biogas production (methane yield per g VS added was 0.22-0.24 L g -1 for both systems).

Gadolinium-based Contrast Media, Cerebrospinal Fluid and the Glymphatic System: Possible Mechanisms for the Deposition of Gadolinium in the Brain.

PubMed

Taoka, Toshiaki; Naganawa, Shinji

2018-04-10

After Kanda's first report in 2014 on gadolinium (Gd) deposition in brain tissue, a considerable number of studies have investigated the explanation for the observation. Gd deposition in brain tissue after repeated administration of gadolinium-based contrast medium (GBCM) has been histologically proven, and chelate stability has been shown to affect the deposition. However, the mechanism for this deposition has not been fully elucidated. Recently, a hypothesis was introduced that involves the 'glymphatic system', which is a coined word that combines 'gl' for glia cell and 'lymphatic' system. According to this hypothesis, the perivascular space functions as a conduit for cerebrospinal fluid to flow into the brain parenchyma. The perivascular space around the arteries allows cerebrospinal fluid to enter the interstitial space of the brain tissue through water channels controlled by aquaporin 4. The cerebrospinal fluid entering the interstitial space clears waste proteins from the tissue. It then flows into the perivascular space around the vein and is discharged outside the brain. In addition to the hypothesis regarding the glymphatic system, some reports have described that after GBCM administration, some of the GBCM distributes through systemic blood circulation and remains in other compartments including the cerebrospinal fluid. It is thought that the GBCM distributed into the cerebrospinal fluid cavity via the glymphatic system may remain in brain tissue for a longer duration compared to the GBCM in systemic circulation. Glymphatic system may of course act as a clearance system for GBCM from brain tissue. Based on these findings, the mechanism for Gd deposition in the brain will be discussed in this review. The authors speculate that the glymphatic system may be the major contributory factor to the deposition and clearance of gadolinium in brain tissue.

Magnetic Resonance Imaging as a Predictor of Survival Free of Life-Threatening Arrhythmias and Transplantation in Cardiac Sarcoidosis.

PubMed

Ekström, Kaj; Lehtonen, Jukka; Hänninen, Helena; Kandolin, Riina; Kivistö, Sari; Kupari, Markku

2016-05-02

Cardiac magnetic resonance imaging has a key role in today's diagnosis of cardiac sarcoidosis. We set out to investigate whether cardiac magnetic resonance imaging also helps predict outcome in cardiac sarcoidosis. Our work involved 59 patients with cardiac sarcoidosis (38 female, mean age 46±10 years) seen at our hospital since February 2004 and followed up after contrast-enhanced cardiac magnetic resonance imaging. The extent of myocardial late gadolinium enhancement (measured as percentage of left ventricular mass), the volumes and ejection fractions of the left and right ventricles, and the thickness of the basal interventricular septum were determined and analyzed for prognostic significance. By April 2015, 23 patients had reached the study's end point, consisting of a composite of cardiac death (n=3), cardiac transplantation (n=1), and occurrence of life-threatening ventricular tachyarrhythmias (n=19; ventricular fibrillation in 5 and sustained ventricular tachycardia in 14 patients). In univariate analysis, myocardial extent of late gadolinium enhancement predicted event-free survival, as did scar-like thinning (<4 mm) of the basal interventricular septum and the ejection fraction of the right ventricle (P<0.05 for all). In multivariate Cox regression analysis, extent of late gadolinium enhancement was the only independent predictor of outcome events on cardiac magnetic resonance imaging, with a hazard ratio of 2.22 per tertile (95% CI 1.07-4.59). An extent of late gadolinium enhancement >22% (third tertile) had positive and negative predictive values for serious cardiac events of 75% and 76%, respectively. Findings on cardiac magnetic resonance imaging and the extent of myocardial late gadolinium enhancement in particular help predict serious cardiac events in cardiac sarcoidosis. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Penetration and distribution of gadolinium-based contrast agents into the cerebrospinal fluid in healthy rats: a potential pathway of entry into the brain tissue.

PubMed

Jost, Gregor; Frenzel, Thomas; Lohrke, Jessica; Lenhard, Diana Constanze; Naganawa, Shinji; Pietsch, Hubertus

2017-07-01

Signal hyperintensity on unenhanced MRI in certain brain regions has been reported after multiple administrations of some, but not all, gadolinium-based contrast agents (GBCAs). One potential initial pathway of GBCA entry into the brain, infiltration from blood into the cerebrospinal fluid (CSF), was systematically evaluated in this preclinical study. GBCA infiltration and distribution in the CSF were investigated in healthy rats using repeated fluid-attenuated MRI up to 4 h after high-dose (1.8 mmol/kg) administration of six marketed and one experimental GBCA. Additionally, gadolinium measurements in CSF, blood and brain tissue samples (after 24 h) were performed using inductively coupled plasma mass spectrometry. Enhanced MRI signals in the CSF spaces with similar distribution kinetics were observed for all GBCAs. No substantial differences in the gadolinium concentrations among the marketed GBCAs were found in the CSF, blood or brain tissue. After 4.5 h, the concentration in the CSF was clearly higher than in blood but was almost completely cleared and lower than the brain tissue concentration after 24 h. In contrast to the brain signal hyperintensities, no differences in penetration and distribution into the CSF of healthy rats exist among the marketed GBCAs. • Gadolinium-based contrast agents can cross the blood-CSF barrier. • Fluid-attenuated MRI shows GBCA distribution with CSF flow. • GBCA structure and physicochemical properties do not impact CSF penetration and distribution. • GBCA clearance from CSF was almost complete within 24 h in rats. • CSF is a potential pathway of GBCA entry into the brain.

Gadolinium-based Contrast Media, Cerebrospinal Fluid and the Glymphatic System: Possible Mechanisms for the Deposition of Gadolinium in the Brain

PubMed Central

Taoka, Toshiaki; Naganawa, Shinji

2018-01-01

After Kanda’s first report in 2014 on gadolinium (Gd) deposition in brain tissue, a considerable number of studies have investigated the explanation for the observation. Gd deposition in brain tissue after repeated administration of gadolinium-based contrast medium (GBCM) has been histologically proven, and chelate stability has been shown to affect the deposition. However, the mechanism for this deposition has not been fully elucidated. Recently, a hypothesis was introduced that involves the ‘glymphatic system’, which is a coined word that combines ‘gl’ for glia cell and ‘lymphatic’ system. According to this hypothesis, the perivascular space functions as a conduit for cerebrospinal fluid to flow into the brain parenchyma. The perivascular space around the arteries allows cerebrospinal fluid to enter the interstitial space of the brain tissue through water channels controlled by aquaporin 4. The cerebrospinal fluid entering the interstitial space clears waste proteins from the tissue. It then flows into the perivascular space around the vein and is discharged outside the brain. In addition to the hypothesis regarding the glymphatic system, some reports have described that after GBCM administration, some of the GBCM distributes through systemic blood circulation and remains in other compartments including the cerebrospinal fluid. It is thought that the GBCM distributed into the cerebrospinal fluid cavity via the glymphatic system may remain in brain tissue for a longer duration compared to the GBCM in systemic circulation. Glymphatic system may of course act as a clearance system for GBCM from brain tissue. Based on these findings, the mechanism for Gd deposition in the brain will be discussed in this review. The authors speculate that the glymphatic system may be the major contributory factor to the deposition and clearance of gadolinium in brain tissue. PMID:29367513

Hyperintense Dentate Nuclei on T1-Weighted MRI: Relation to Repeat Gadolinium Administration

PubMed Central

Adin, M.E.; Kleinberg, L.; Vaidya, D.; Zan, E.; Mirbagheri, S.; Yousem, D.M.

2016-01-01

BACKGROUND AND PURPOSE A hyperintense appearance of the dentate nucleus on T1-weighted MR images has been related to various clinical conditions, but the etiology remains indeterminate. We aimed to investigate the possible associations between a hyperintense appearance of the dentate nucleus on T1-weighted MR images in patients exposed to radiation and factors including, but not limited to, the cumulative number of contrast-enhanced MR images, amount of gadolinium administration, dosage of ionizing radiation, and patient demographics. MATERIALS AND METHODS The medical records of 706 consecutive patients who were treated with brain irradiation at The Johns Hopkins Medical Institutions between 1995 and 2010 were blindly reviewed by 2 readers. RESULTS One hundred eighty-four subjects were included for dentate nuclei analysis. Among the 184 subjects who cumulatively underwent 2677 MR imaging studies following intravenous gadolinium administration, 103 patients had hyperintense dentate nuclei on precontrast T1-weighted MR images. The average number of gadolinium-enhanced MR imaging studies performed in the group with normal dentate nuclei was significantly lower than that of the group with hyperintense dentate nuclei. The average follow-up time was 62.5 months. No significant difference was observed between hyperintense and normal dentate nuclei groups in terms of exposed radiation dose, serum creatinine and calcium/phosphate levels, patient demographics, history of chemotherapy, and strength of the scanner. No dentate nuclei abnormalities were found on the corresponding CT scans of patients with hyperintense dentate nuclei (n = 44). No dentate nuclei abnormalities were found in 53 healthy volunteers. CONCLUSIONS Repeat performance of gadolinium-enhanced studies likely contributes to a long-standing hyperintense appearance of dentate nuclei on precontrast T1-weighted-MR images. PMID:26294649

Nanoamplifiers synthesized from gadolinium and gold nanocomposites for magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Tian, Xiumei; Shao, Yuanzhi; He, Haoqiang; Liu, Huan; Shen, Yingying; Huang, Wenlin; Li, Li

2013-03-01

We have synthesized an efficient and highly sensitive nanoamplifier composed of gadolinium-doped silica nanoparticles and gold nanoparticles (AuNPs). Magnetic resonance imaging (MRI) in vitro and in vivo assays revealed enhancement of signal sensitivity, which may be explained by electron transfer between water and gadolinium-doped nanoparticles, apparent in the presence of gold. In vitro and in vivo evaluation demonstrated nanoamplifier incurred minimal cytotoxicity and immunotoxicity, increased stability, and gradual excretion patterns. Tumor targeted properties were preliminarily determined when the nanoamplifier was injected into mouse models of colon cancer liver metastasis. Furthermore, although AuNPs departed from the nanoamplifiers in specific mice tissues, optical and magnetic resonance imaging was efficient, especially in metastatic tumors. These assays validate our nanoamplifier as an effective MRI signal enhancer with sensitive cancer diagnosis potential.We have synthesized an efficient and highly sensitive nanoamplifier composed of gadolinium-doped silica nanoparticles and gold nanoparticles (AuNPs). Magnetic resonance imaging (MRI) in vitro and in vivo assays revealed enhancement of signal sensitivity, which may be explained by electron transfer between water and gadolinium-doped nanoparticles, apparent in the presence of gold. In vitro and in vivo evaluation demonstrated nanoamplifier incurred minimal cytotoxicity and immunotoxicity, increased stability, and gradual excretion patterns. Tumor targeted properties were preliminarily determined when the nanoamplifier was injected into mouse models of colon cancer liver metastasis. Furthermore, although AuNPs departed from the nanoamplifiers in specific mice tissues, optical and magnetic resonance imaging was efficient, especially in metastatic tumors. These assays validate our nanoamplifier as an effective MRI signal enhancer with sensitive cancer diagnosis potential. Electronic supplementary information (ESI) available: Protocols for the characterization, immunotoxicity and pharmacokinetics analyses. Additional supporting figures. See DOI: 10.1039/c3nr00170a

Serial nonenhancing magnetic resonance imaging scans of high grade glioblastoma multiforme.

PubMed Central

Moore-Stovall, J.; Venkatesh, R.

1993-01-01

Magnetic resonance imaging (MRI) from clinical experience has proven to be superior to all other diagnostic imaging modalities, including computed tomography (CT) in the detection of intracranial neoplasms. Although glioblastoma multiforme presents a challenge for all diagnostic imaging modalities including MRI, MRI is paramount to CT in detecting subtle abnormal water accumulation in brain tissue caused by tumor even before there is disruption of the blood brain barrier. Currently, clinical research and investigational trials on nonionic gadolinium contrast agents have proven that nonionic gadolinium HP-DO3A (ProHance) contrast agents have lower osmolality and greater stability, which make them superior compounds to gadolinium diethylenetriamine-pentacetic acid (Gd-DTPA). Therefore, the nonionic gadolinium contrasts have been safely administered more rapidly, in higher or multiple doses for contrast enhanced MRI without adverse side effects or changes in serum iron or total bilirubin, and the intensity of the area of enhancement and number of lesions detected were superior to that of Gd-DTPA (Magnevist) at the standard dose (0.1 mmol/Kg). Perhaps if the nonionic gadolinium contrast agent, ProHance, had been approved by the Food and Drug Administration (FDA) when this MRI was performed in 1990 it would have aided in providing contrast enhancement and visualization of the tumor lesion to assist in patient diagnosis and management. Magnetic resonance imaging also provides unique multiplanar capabilities that allow for optimal visualization of the temporal and occipital lobes of the brain without bone interference.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9A Figure 9B Figure 10 Figure 11 Figure 12 Figure 13 PMID:8382751

Frequency of second mesiobuccal canal in permanent maxillary first molars using the operating microscope and selective dentin removal: A clinical study.

PubMed

Das, Suroopa; Warhadpande, Manjusha M; Redij, Saurabh A; Jibhkate, N G; Sabir, Husain

2015-01-01

The aim of this study was to investigate whether the combination of operating microscope and selective dentin removal increased the frequency of second mesiobuccal (MB2) canal detection in permanent maxillary first molar teeth. One hundred fifty permanent maxillary first molars indicated for root canal treatment were randomly selected from patients belonging to the age group of 18-45 years irrespective of gender. After access cavity preparation and location of main canals, the MB2 canal orifice was sought in all teeth with an endodontic explorer under direct vision (Stage I), then under magnification with the aid of operating microscope (Stage II) and finally with the combined use of operating microscope and selective dentin removal (Stage III). MB2 canals were detected in 36%, 54% and 72% of the teeth in Stages I-III, respectively. This study demonstrated that dental operating microscope when used along with adjunctive aids such as selective dentin removal/troughing and good clinical knowledge will increase the ability of dental clinician to locate MB2 canals.

Gadolinium-Induced Fibrosis.

PubMed

Todd, Derrick J; Kay, Jonathan

2016-01-01

Gadolinium-based contrast agents (GBCAs), once believed to be safe for patients with renal disease, have been strongly associated with nephrogenic systemic fibrosis (NSF), a severe systemic fibrosing disorder that predominantly afflicts individuals with advanced renal dysfunction. We provide a historical perspective on the appearance and disappearance of NSF, including its initial recognition as a discrete clinical entity, its association with GBCA exposure, and the data supporting a causative relationship between GBCA exposure and NSF. On the basis of this body of evidence, we propose that the name gadolinium-induced fibrosis (GIF) more accurately reflects the totality of knowledge regarding this disease. Use of high-risk GBCAs, such as formulated gadodiamide, should be avoided in patients with renal disease. Restriction of GBCA use in this population has almost completely eradicated new cases of this debilitating condition. Emerging antifibrotic therapies may be useful for patients who suffer from GIF.

Biocompatible Polyhydroxyethylaspartamide-based Micelles with Gadolinium for MRI Contrast Agents

PubMed Central

2010-01-01

Biocompatible poly-[N-(2-hydroxyethyl)-d,l-aspartamide]-methoxypoly(ethyleneglycol)-hexadecylamine (PHEA-mPEG-C16) conjugated with 1,4,7,10-tetraazacyclododecan-1,4,7,10-tetraacetic acid-gadolinium (DOTA-Gd) via ethylenediamine (ED) was synthesized as a magnetic resonance imaging (MRI) contrast agent. Amphiphilic PHEA-mPEG-C16-ED-DOTA-Gd forms micelle in aqueous solution. All the synthesized materials were characterized by proton nuclear magnetic resonance (1H NMR). Micelle size and shape were examined by dynamic light scattering (DLS) and atomic force microscopy (AFM). Micelles with PHEA-mPEG-C16-ED-DOTA-Gd showed higher relaxivities than the commercially available gadolinium contrast agent. Moreover, the signal intensity of a rabbit liver was effectively increased after intravenous injection of PHEA-mPEG-C16-ED-DOTA-Gd. PMID:21170410

Method of separating and purifying gadolinium-153

DOEpatents

Bray, Lane A [Richland, WA; Corneillie, Todd M [Davis, CA

2001-01-01

The present invention is an improvement to the method of separating and purifying gadolinium from a mixture of gadolinium and europium having the steps of (a) dissolving the mixture in an acid; (b) reducing europium+3 to europium+2; and (c) precipitating the europium+2 with a sulfate ion in a superstoichiometric amount; wherein the improvement is achieved by using one or more of the following: (i) the acid is an anoic acid; (ii) the reducing is with zinc metal in the absence of a second metal or with an amount of the second metal that is ineffective in the reducing; (iii) adding a group IIA element after step (c) for precipitating the excess sulfate prior to repeating step (c); (iv) the sulfate is a sulfate salt with a monovalent cation; (v) adding cold europium+3 prior to repeating step (c).

The effect of boron and gadolinium burnable poisons on the hot-to-cold reactivity swing of a pressurized water reactor assembly

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

Galperin, A.; Segev, M.; Radkowsky, A.

1986-11-01

Control requirements for advanced pressurized water reactor designs must be met with heavy loadings of burnable poison rods, the required reactivity hold-down typically amounting to 30% or more in a poisoned subassembly. Two apparent choices for poisons are natural boron rods and natural gadolinium rods. Studied and analyzed is the effect of these two poisons on the hot-to-cold reactivity upswing. Compared with an upswing of 2.9% in a nonpoisoned assembly, the upswing in the gadolinium-poisoned assembly is 3.0%, and the upswing in the boron-poisoned assembly is 8.8%. Thus the hot-to-cold control penalty is almost nil for the choice of gadoliniummore » and is considerable for the choice of boron.« less

Insights into the use of gadolinium and gadolinium/boron-based agents in imaging-guided neutron capture therapy applications.

PubMed

Deagostino, Annamaria; Protti, Nicoletta; Alberti, Diego; Boggio, Paolo; Bortolussi, Silva; Altieri, Saverio; Crich, Simonetta Geninatti

2016-05-01

Gadolinium neutron capture therapy (Gd-NCT) is currently under development as an alternative approach for cancer therapy. All of the clinical experience to date with NCT is done with (10)B, known as boron neutron capture therapy (BNCT), a binary treatment combining neutron irradiation with the delivery of boron-containing compounds to tumors. Currently, the use of Gd for NCT has been getting more attention because of its highest neutron cross-section. Although Gd-NCT was first proposed many years ago, its development has suffered due to lack of appropriate tumor-selective Gd agents. This review aims to highlight the recent advances for the design, synthesis and biological testing of new Gd- and B-Gd-containing compounds with the task of finding the best systems able to improve the NCT clinical outcome.

A two-stage magnetic refrigerator for astronomical applications with reservoir temperatures above 4 K

NASA Astrophysics Data System (ADS)

Hagmann, C.; Richards, P. L.

1993-02-01

We propose a novel adiabatic demagnetization refrigerator (ADR) to produce temperatures as low as 100 mK starting from a high temperature reservoir between 4 and 8 K. The high temperature reservoir for the ADR can be provided by a mechanical cooler or an unpumped liquid helium bath. This refrigerator can be used to cool bolometric infrared detectors for low background astronomy from mountain tops, balloons or satellites as well as to cool cryogenic x-ray detectors. The two-stage ADR consists of a single magnet with a paramagnetic chromic-cesium-alum (CCA) salt pill to produce the low temperature and paramagnetic gadolinium-gallium-garnet (GGG) as the first stage to intercept heat from the high temperature reservoir. Thermal contact between the paramagnets and the reservoir during magnetization is made with a mechanical heat switch. The ADR is suspended with Kevlar chords under tension for high mechanical stiffness and low parasitic heat leak. In a single cycle, the ADR maintains a temperature of 100 mK for 10 to 100 hours. This time depends strongly on the magnetic field and reservoir temperature but not on the volume of the paramagnetic material as long as the heat leak is dominated by the suspension.

A two-stage magnetic refrigerator for astronomical applications with reservoir temperatures above 4 K

NASA Technical Reports Server (NTRS)

Hagmann, C.; Richards, P. L.

1993-01-01

We propose a novel adiabatic demagnetization refrigerator (ADR) to produce temperatures as low as 100 mK starting from a high temperature reservoir between 4 and 8 K. The high temperature reservoir for the ADR can be provided by a mechanical cooler or an unpumped liquid helium bath. This refrigerator can be used to cool bolometric infrared detectors for low background astronomy from mountain tops, balloons or satellites as well as to cool cryogenic x-ray detectors. The two-stage ADR consists of a single magnet with a paramagnetic chromic-cesium-alum (CCA) salt pill to produce the low temperature and paramagnetic gadolinium-gallium-garnet (GGG) as the first stage to intercept heat from the high temperature reservoir. Thermal contact between the paramagnets and the reservoir during magnetization is made with a mechanical heat switch. The ADR is suspended with Kevlar chords under tension for high mechanical stiffness and low parasitic heat leak. In a single cycle, the ADR maintains a temperature of 100 mK for 10 to 100 hours. This time depends strongly on the magnetic field and reservoir temperature but not on the volume of the paramagnetic material as long as the heat leak is dominated by the suspension.

Two-stage gas-phase bioreactor for the combined removal of hydrogen sulphide, methanol and alpha-pinene.

PubMed

Rene, Eldon R; Jin, Yaomin; Veiga, María C; Kennes, Christian

2009-11-01

Biological treatment systems have emerged as cost-effective and eco-friendly techniques for treating waste gases from process industries at moderately high gas flow rates and low pollutant concentrations. In this study, we have assessed the performance of a two-stage bioreactor, namely a biotrickling filter packed with pall rings (BTF, 1st stage) and a perlite + pall ring mixed biofilter (BF, 2nd stage) operated in series, for handling a complex mixture of hydrogen sulphide (H2S), methanol (CH3OH) and alpha-pinene (C10H16). It has been reported that the presence of H2S can reduce the biofiltration efficiency of volatile organic compounds (VOCs) when both are present in the gas mixture. Hydrogen sulphide and methanol were removed in the first stage BTF, previously inoculated with H2S-adapted populations and a culture containing Candida boidinii, an acid-tolerant yeast, whereas, in the second stage, alpha-pinene was removed predominantly by the fungus Ophiostoma stenoceras. Experiments were conducted in five different phases, corresponding to inlet loading rates varying between 2.1 and 93.5 g m(-3) h(-1) for H2S, 55.3 and 1260.2 g m(-3) h(-1) for methanol, and 2.8 and 161.1 g m(-3) h(-1) for alpha-pinene. Empty bed residence times were varied between 83.4 and 10 s in the first stage and 146.4 and 17.6 s in the second stage. The BTF, working at a pH as low as 2.7 as a result of H2S degradation, removed most of the H2S and methanol but only very little alpha-pinene. On the other hand, the BF, at a pH around 6.0, removed the rest of the H2S, the non-degraded methanol and most of the alpha-pinene vapours. Attempts were originally made to remove the three pollutants in a single acidophilic bioreactor, but the Ophiostoma strain was hardly active at pH <4. The maximum elimination capacities (ECs) reached by the two-stage bioreactor for individual pollutants were 894.4 g m(-3) h(-1) for methanol, 45.1 g m(-3) h(-1) for H2S and 138.1 g m(-3) h(-1) for alpha-pinene. The results from this study showed the potential effectiveness of a two-stage bioreactor for treating H2S together with two hydrophilic and hydrophobic VOCs that are typically emitted from wood industries.

Tunable Microwave Transversal Filters.

DTIC Science & Technology

1984-05-01

magnetostatic waves MSW propagating at microwave frequency in magnetically biased, liquid phase epitaxial films of yttrium iron garnet (YIG) grown on...25 uM-thick 3 mm-wide and 15 mm-long YIG film grown by liquid phase epitaxy On a 500 uM-thick ( ) gadolinium gallium garnet (GGG) substrate was used...obtained. The delay line material was prepared by growing YIG films on one inch diameter gallium gadolinium garnet (GGG) wafers using the liquid

Optical Properties of Nd Doped Rare Earth Vanadates (Preprint)

DTIC Science & Technology

2010-07-01

Rare earth orthovanadates are being used as substitute for traditional solid state laser hosts such as yttrium aluminium garnet (YAG). While the most...common of these is yttrium orthovanadate, other rare earth vanadates such as lutetium vanadate and gadolinium vanadate are being used for their... gadolinium vanadate are being used for their special properties in certain applications. We report new measurements of the refractive indices and thermo

Neuroprotective effect of gadolinium: a stretch-activated calcium channel blocker in mouse model of ischemia-reperfusion injury.

PubMed

Gulati, Puja; Muthuraman, Arunachalam; Jaggi, Amteshwar S; Singh, Nirmal

2013-03-01

The present study was designed to investigate the potential of gadolinium, a stretch-activated calcium channel blocker in ischemic reperfusion (I/R)-induced brain injury in mice. Bilateral carotid artery occlusion of 12 min followed by reperfusion for 24 h was given to induce cerebral injury in male Swiss mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was assessed using Morris water maze test and motor incoordination was evaluated using rota-rod, lateral push, and inclined beam walking tests. In addition, total calcium, thiobarbituric acid reactive substance (TBARS), reduced glutathione (GSH), and acetylcholinesterase (AChE) activity were also estimated in brain tissue. I/R injury produced a significant increase in cerebral infarct size. A significant loss of memory along with impairment of motor performance was also noted. Furthermore, I/R injury also produced a significant increase in levels of TBARS, total calcium, AChE activity, and a decrease in GSH levels. Pretreatment of gadolinium significantly attenuated I/R-induced infarct size, behavioral and biochemical changes. On the basis of the present findings, we can suggest that opening of stretch-activated calcium channel may play a critical role in ischemic reperfusion-induced brain injury and that gadolinium has neuroprotective potential in I/R-induced injury.

Safe Use of Contrast Media: What the Radiologist Needs to Know.

PubMed

Beckett, Katrina R; Moriarity, Andrew K; Langer, Jessica M

2015-10-01

Iodinated and gadolinium-based contrast media are used on a daily basis in most radiology practices. These agents often are essential to providing accurate diagnoses, and are nearly always safe and effective when administered correctly. However, reactions to contrast media do occur and can be life threatening. Therefore, it is critical for faculty and staff to know how reactions to contrast agents manifest and how to treat them promptly. The decline in renal function seen occasionally after intravenous administration of iodinated contrast agents is poorly understood and likely multifactorial, and its association with the contrast medium may be overemphasized. However, it is important that radiologists be aware of current understanding and strategies to decrease the incidence of renal dysfunction. Nephrogenic systemic fibrosis, a skin disease, is an adverse reaction related to use of some gadolinium-based contrast agents in patients with chronic renal failure. The types of gadolinium most often associated with this condition and the indications for withholding gadolinium are important and are discussed in this article. The use of enteric contrast agents and contrast agents during pregnancy and nursing are reviewed briefly. Current knowledge for safe use of contrast media and key concepts that all radiologists should know are summarized in this review. © RSNA, 2015.

Study of the Photon Strength Functions for Gadolinium Isotopes with the DANCE Array

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

Dashdorj, D.; Mitchell, G. E.; Baramsai, B.

2009-03-10

The gadolinium isotopes are interesting for reactor applications as well as for medicine and astrophysics. The gadolinium isotopes have some of the largest neutron capture cross sections. As a consequence they are used in the control rod in reactor fuel assembly. From the basic science point of view, there are seven stable isotopes of gadolinium with varying degrees of deformation. Therefore they provide a good testing ground for the study of deformation dependent structure such as the scissors mode. Decay gamma rays following neutron capture on Gd isotopes are detected by the DANCE array, which is located at flight pathmore » 14 at the Lujan Neutron Scattering Center at Los Alamos National Laboratory. The high segmentation and close packing of the detector array enable gamma-ray multiplicity measurements. The calorimetric properties of the DANCE array coupled with the neutron time-of-flight technique enables one to gate on a specific resonance of a specific isotope in the time-of-flight spectrum and obtain the summed energy spectrum for that isotope. The singles gamma-ray spectrum for each multiplicity can be separated by their DANCE cluster multiplicity. Various photon strength function models are used for comparison with experimentally measured DANCE data and provide insight for understanding the statistical decay properties of deformed nuclei.« less

Gadolinium-loaded Plastic Scintillators for Thermal Neutron Detection using Compensation

NASA Astrophysics Data System (ADS)

Dumazert, Jonathan; Coulon, Romain; Hamel, Matthieu; Carrel, Frédérick; Sguerra, Fabien; Normand, Stéphane; Méchin, Laurence; Bertrand, Guillaume H. V.

2016-06-01

Plastic scintillator loading with gadolinium-rich organometallic complexes shows a high potential for the deployment of efficient and cost-effective neutron detectors. Due to the low-energy photon and electron signature of thermal neutron capture by Gd-155 and Gd-157, alternative treatment to pulse-shape discrimination has to be proposed in order to display a count rate. This paper discloses the principle of a compensation method applied to a two-scintillator system: a detection scintillator interacts with photon and fast neutron radiation and is loaded with gadolinium organometallic compound to become a thermal neutron absorber, while a not-gadolinium loaded compensation scintillator solely interacts with the fast neutron and photon part of incident radiation. After the nonlinear smoothing of the counting signals, a hypothesis test determines whether the resulting count rate post-background response compensation falls into statistical fluctuations or provides a robust indication of neutron activity. Laboratory samples are tested under both photon and neutron irradiations, allowing the authors to investigate the performance of the overall detection system in terms of sensitivity and detection limits, especially with regards to a similar-active volume He-3 based commercial counter. The study reveals satisfactory figures of merit in terms of sensitivity and directs future investigation toward promising paths.

Ferromagnetic coupling in the three-dimensional malonato-bridged gadoliniumIII complex [Gd2(mal)3(H2O)6] (H2mal = malonic acid).

PubMed

Hernández-Molina, María; Ruiz-Pérez, Catalina; López, Trinidad; Lloret, Francesc; Julve, Miguel

2003-09-08

The novel gadolinium(III) complex of formula [Gd(2)(mal)(3)(H(2)O)(6)] (1) (H(2)mal = 1,3-propanedioic acid) has been prepared and characterized by X-ray diffraction analysis. Crystal data for 1: monoclinic, space group I2/a, a = 11.1064(10) A, b = 12.2524(10) A, c =13.6098(2) A, beta = 92.925(10) degrees, U = 1849.5(3) A(3), Z = 4. Compound 1 is a three-dimensional network made up of malonate-bridged gadolinium(III) ions where the malonate exhibits two bridging modes, eta(5)-bidentate + unidentate and eta(3):eta(3) + bis(unidentate). The gadolinium atom is nine-coordinate with three water molecules and six malonate oxygen atoms from three malonate ligands forming a distorted monocapped square antiprism. The shortest metal-metal separations are 4.2763(3) A [through the oxo-carboxylate bridge] and 6.541(3) A [through the carboxylate in the anti-syn coordination mode]. The value of the angle at the oxo-carboxylate atom is 116.8(2) degrees. Variable-temperature magnetic susceptibility measurements reveal the occurrence of a significant ferromagnetic interaction through the oxo-carboxylate pathway (J = +0.048(1) cm(-1), H = -JS(Gd(1)) x S(Gd(1a))).

High-pressure high-temperature phase diagram of gadolinium studied using a boron-doped heater anvil

NASA Astrophysics Data System (ADS)

Montgomery, J. M.; Samudrala, G. K.; Velisavljevic, N.; Vohra, Y. K.

2016-04-01

A boron-doped designer heater anvil is used in conjunction with powder x-ray diffraction to collect structural information on a sample of quasi-hydrostatically loaded gadolinium metal up to pressures above 8 GPa and 600 K. The heater anvil consists of a natural diamond anvil that has been surface modified with a homoepitaxially grown chemical-vapor-deposited layer of conducting boron-doped diamond, and is used as a DC heating element. Internally insulating both diamond anvils with sapphire support seats allows for heating and cooling of the high-pressure area on the order of a few tens of seconds. This device is then used to scan the phase diagram of the sample by oscillating the temperature while continuously increasing the externally applied pressure and collecting in situ time-resolved powder diffraction images. In the pressure-temperature range covered in this experiment, the gadolinium sample is observed in its hcp, αSm, and dhcp phases. Under this temperature cycling, the hcp → αSm transition proceeds in discontinuous steps at points along the expected phase boundary. From these measurements (representing only one hour of synchrotron x-ray collection time), a single-experiment equation of state and phase diagram of each phase of gadolinium is presented for the range of 0-10 GPa and 300-650 K.

Core-shell monodisperse spherical mSiO2/Gd2O3:Eu3+@mSiO2 particles as potential multifunctional theranostic agents

NASA Astrophysics Data System (ADS)

Eurov, Daniil A.; Kurdyukov, Dmitry A.; Kirilenko, Demid A.; Kukushkina, Julia A.; Nashchekin, Alexei V.; Smirnov, Alexander N.; Golubev, Valery G.

2015-02-01

Core-shell nanoparticles with diameters in the range 100-500 nm have been synthesized as monodisperse spherical mesoporous (pore diameter 3 nm) silica particles with size deviation of less than 4 %, filled with gadolinium and europium oxides and coated with a mesoporous silica shell. It is shown that the melt technique developed for filling with gadolinium and europium oxides provides a nearly maximum filling of mesopores in a single-run impregnation, with gadolinium and europium uniformly distributed within the particles and forming no bulk oxides on their surface. The coating with a shell does not impair the monodispersity and causes no coagulation. The coating technique enables controlled variation of the shell thickness within the range 5-100 % relative to the core diameter. The thus produced nanoparticles are easily dispersed in water, have large specific surface area (300 m2 g-1) and pore volume (0.3 cm3 g-1), and are bright solid phosphor with superior stability in aqueous media. The core-shell structured particles can be potentially used for cancer treatment as a therapeutic agent (gadolinium neutron-capture therapy and drug delivery system) and, simultaneously, as a multimodal diagnostic tool (fluorescence and magnetic resonance imaging), thereby serving as a multifunctional theranostic agent.

Laparoscopic sleeve gastrectomy as revisional surgery for adjustable gastric band erosion.

PubMed

Park, Yeon Ho; Kim, Seong Min

2014-09-01

Laparoscopic sleeve gastrectomy (LSG) has been increasingly adopted as a revisional surgery for failed gastric banding. However, little information is available regarding the outcome of revisional LSG for band erosion. A retrospective database analysis was performed to study LSG as revisional surgery for band erosion. For staged revision, we waited a minimum of 3 months after band removal, and for single-stage revision, the band was removed by gastrotomy, and sleeve gastrectomy was performed at the same time. Main outcome measures were success rates of therapeutic strategies, morbidity, and mortality rates, length of stay, and body mass index (BMI) (percentage excess weight loss [%EWL]) before and after revision. From March 2011 to February 2013, 9 female patients underwent revisional LSG. Average age was 34.7 years. Six patients underwent a staged procedure, and the other 3 underwent a single-stage revision. Among the 6 staged patients, eroded bands had been removed by laparoscopy in 4 and by endoscopy in 2 without complications. Their LSGs were performed at a median of 4.4 months after band removal. Another 2 patients underwent single-stage revision. In the last patient, band erosion was incidentally found during a revisional LSG for insufficient weight loss. No mortality occurred. There were one stenosis and two proximal leaks. Two patients with leak underwent total gastrectomy and fistulojejunostomy. After a mean follow-up of 19.1 months, all 9 patients exhibited weight loss. The mean (±standard deviation [SD]) pre- and post-LSG BMIs were 34.0±4.4 and 25.6±2.1 kg/m(2), respectively, and their mean (±SD) %EWL from prebanding was 86.8±10.1%. Revisional LSG resulted in a further median %EWL of 28.0% (range, 7.9%-68.9%) versus weight at time of band removal. Revisional LSG after band erosion was found to be feasible and effective. However, it is prone to severe complication. In selected cases of band erosion, LSG can be performed at the time of band removal in a single stage.

Sperm removal during copulation confirmed in the oldest extant damselfly, Hemiphlebia mirabilis

PubMed Central

2016-01-01

Postcopulatory sexual selection may favour mechanisms to reduce sperm competition, like physical sperm removal by males. To investigate the origin of sperm removal, I studied the reproductive behaviour and mechanisms of sperm competition in the only living member of the oldest damselfly family, Hemiphlebia mirabilis, one species that was considered extinct in the 1980s. This species displays scramble competition behaviour. Males search for females with short flights and both sexes exhibit a conspicuous “abdominal flicking”. This behaviour is used by males during an elaborate precopulatory courtship, unique among Odonata. Females use a similar display to reject male attempts to form tandem, but eventually signal receptivity by a particular body position. Males immobilise females during courtship using their legs, which, contrarily to other damselflies, never autotomise. Copulation is short (range 4.1–18.7 min), and occurs in two sequential stages. In the first stage, males remove part of the stored sperm, and inseminate during the second stage, at the end of mating. The male genital ligula matches the size and form of female genitalia, and ends by two horns covered by back-oriented spines. The volume of sperm in females before copulation was 2.7 times larger than the volume stored in females whose copulation was interrupted at the end of stage I, indicative of a significant sperm removal. These results point out that sperm removal is an old character in the evolution of odonates, possibly dating back to the Permian. PMID:27257552

COD removal characteristics in air-cathode microbial fuel cells.

PubMed

Zhang, Xiaoyuan; He, Weihua; Ren, Lijiao; Stager, Jennifer; Evans, Patrick J; Logan, Bruce E

2015-01-01

Exoelectrogenic microorganisms in microbial fuel cells (MFCs) compete with other microorganisms for substrate. In order to understand how this affects removal rates, current generation, and coulombic efficiencies (CEs), substrate removal rates were compared in MFCs fed a single, readily biodegradable compound (acetate) or domestic wastewater (WW). Removal rates based on initial test conditions fit first-order kinetics, but rate constants varied with circuit resistance. With filtered WW (100Ω), the rate constant was 0.18h(-)(1), which was higher than acetate or filtered WW with an open circuit (0.10h(-)(1)), but CEs were much lower (15-24%) than acetate. With raw WW (100Ω), COD removal proceeded in two stages: a fast removal stage with high current production, followed by a slower removal with little current. While using MFCs increased COD removal rate due to current generation, secondary processes will be needed to reduce COD to levels suitable for discharge. Copyright © 2014 Elsevier Ltd. All rights reserved.

True intraspinal neurenteric cyst in the lumbosacral region--case report.

PubMed

Yunoki, Masatoshi; Hirashita, Koji; Gohda, Yuji; Yoshino, Kimihiro; Fujimoto, Shunichiro; Mizobuchi, Koichi

2007-05-01

A 56-year-old man presented with a very rare true neurenteric cyst in the conus medullaris without evidence of vertebral or visceral anomaly manifesting as a 6-month history of mild low back and bilateral inguinal pain. No motor weakness was found in the bilateral lower extremities. He had also suffered dysesthesia in the bilateral feet for several weeks before admission. Lumbar spine magnetic resonance (MR) imaging demonstrated a cystic intradural extramedullary mass at the L1-2 levels without enhancement after gadolinium injection. MR imaging, computed tomography, and radiography detected no vertebral anomaly. Lumbar laminectomy at the L1-2 levels was performed and the lesion was incompletely removed. Histological examination showed the cystic wall lined with ciliated columnar epithelium. Neurenteric cyst should be considered in the diagnosis of isolated cystic mass lesion at the lumbosacral region even in the absence of vertebral or visceral abnormality.

An open source, 3D printed preclinical MRI phantom for repeated measures of contrast agents and reference standards.

PubMed

Cox, B L; Ludwig, K D; Adamson, E B; Eliceiri, K W; Fain, S B

2018-03-01

In medical imaging, clinicians, researchers and technicians have begun to use 3D printing to create specialized phantoms to replace commercial ones due to their customizable and iterative nature. Presented here is the design of a 3D printed open source, reusable magnetic resonance imaging (MRI) phantom, capable of flood-filling, with removable samples for measurements of contrast agent solutions and reference standards, and for use in evaluating acquisition techniques and image reconstruction performance. The phantom was designed using SolidWorks, a computer-aided design software package. The phantom consists of custom and off-the-shelf parts and incorporates an air hole and Luer Lock system to aid in flood filling, a marker for orientation of samples in the filled mode and bolt and tube holes for assembly. The cost of construction for all materials is under $90. All design files are open-source and available for download. To demonstrate utility, B 0 field mapping was performed using a series of gadolinium concentrations in both the unfilled and flood-filled mode. An excellent linear agreement (R 2 >0.998) was observed between measured relaxation rates (R 1 /R 2 ) and gadolinium concentration. The phantom provides a reliable setup to test data acquisition and reconstruction methods and verify physical alignment in alternative nuclei MRI techniques (e.g. carbon-13 and fluorine-19 MRI). A cost-effective, open-source MRI phantom design for repeated quantitative measurement of contrast agents and reference standards in preclinical research is presented. Specifically, the work is an example of how the emerging technology of 3D printing improves flexibility and access for custom phantom design.

VEGF Trap in Treating Patients With Recurrent Stage III or Stage IV Melanoma That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-04-26

Ciliary Body and Choroid Melanoma, Medium/Large Size; Extraocular Extension Melanoma; Iris Melanoma; Metastatic Intraocular Melanoma; Recurrent Intraocular Melanoma; Recurrent Melanoma; Stage III Melanoma; Stage IV Melanoma

Local staging and assessment of colon cancer with 1.5-T magnetic resonance imaging

PubMed Central

Blake, Helena; Jeyadevan, Nelesh; Abulafi, Muti; Swift, Ian; Toomey, Paul; Brown, Gina

2016-01-01

Objective: The aim of this study was to assess the accuracy of 1.5-T MRI in the pre-operative local T and N staging of colon cancer and identification of extramural vascular invasion (EMVI). Methods: Between 2010 and 2012, 60 patients with adenocarcinoma of the colon were prospectively recruited at 2 centres. 55 patients were included for final analysis. Patients received pre-operative 1.5-T MRI with high-resolution T2 weighted, gadolinium-enhanced T1 weighted and diffusion-weighted images. These were blindly assessed by two expert radiologists. Accuracy of the T-stage, N-stage and EMVI assessment was evaluated using post-operative histology as the gold standard. Results: Results are reported for two readers. Identification of T3 disease demonstrated an accuracy of 71% and 51%, sensitivity of 74% and 42% and specificity of 74% and 83%. Identification of N1 disease demonstrated an accuracy of 57% for both readers, sensitivity of 26% and 35% and specificity of 81% and 74%. Identification of EMVI demonstrated an accuracy of 74% and 69%, sensitivity 63% and 26% and specificity 80% and 91%. Conclusion: 1.5-T MRI achieved a moderate accuracy in the local evaluation of colon cancer, but cannot be recommended to replace CT on the basis of this study. Advances in knowledge: This study confirms that MRI is a viable alternative to CT for the local assessment of colon cancer, but this study does not reproduce the very high accuracy reported in the only other study to assess the accuracy of MRI in colon cancer staging. PMID:27226219

Non-hypervascular hypointense nodules on Gd-EOB-DTPA-enhanced MRI as a predictor of outcomes for early-stage HCC.

PubMed

Toyoda, Hidenori; Kumada, Takashi; Tada, Toshifumi; Sone, Yasuhiro; Maeda, Atsuyuki; Kaneoka, Yuji

2015-01-01

In patients with hepatocellular carcinoma (HCC), gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) often identifies non-hypervascular hypointense hepatic nodules during the hepatobiliary phase, but their prognostic significance is unclear. We conducted a prospective observational study to investigate the impact of non-hypervascular hypointense hepatic nodules detected by Gd-EOB-DTPA-enhanced MRI on the outcome of patients with early-stage HCC. Post-treatment recurrence and survival rates were analyzed in 138 patients with non-recurrent, early-stage HCC [Barcelona Clinic Liver Cancer (BCLC) stage 0 or A] and Child-Pugh A liver function according to the presence of non-hypervascular hypointense nodules on pretreatment Gd-EOB-DTPA-enhanced MRI. Non-hypervascular hypointense hepatic nodules were detected in 51 (37.0%) patients with early-stage HCC on pretreatment Gd-EOB-DTPA-enhanced MRI. Recurrence rates were significantly higher in patients with non-hypervascular hypointense nodules (p < 0.0001). Based on a multivariate analysis, the presence of non-hypervascular hypointense hepatic nodules on Gd-EOB-DTPA-enhanced MRI was independently associated with an increased recurrence rate, independent of tumor progression or treatment (p = 0.0005). The survival rate was significantly lower in patients with non-hypervascular hypointense nodules on Gd-EOB-DTPA-enhanced MRI (p = 0.0108). In patients with early-stage typical HCC (BCLC 0 or A), the presence of concurrent non-hypervascular hypointense hepatic nodules in the hepatobiliary phase of pretreatment Gd-EOB-DTPA-enhanced MRI is an indicator of higher likelihood of recurrence after treatment and may be a marker for unfavorable outcome.

The use of innovative gadolinium-based contrast agent for MR-diagnosis of cancer in the experiment

NASA Astrophysics Data System (ADS)

Chernov, V.; Medvedeva, A.; Sinilkin, I.; Zelchan, R.; Grigorev, E.; Frolova, I.; Nam, I.

2016-02-01

The present study of the functional suitability and specific activity of the contrast agent gadolinium-based for magnetic resonance imaging demonstrated that the investigated contrast agent intensively accumulates in organs and anatomical structures of the experimental animals. In the model of tumor lesions in animals, study have shown that investigational contrast agent accumulates in the tumor tissue and retained there in for a long enough time.

How to Evaluate and Synthesize Literature Data on Physical Properties.

DTIC Science & Technology

1980-09-01

experimental set-up, refined technique for fabri - cating and installing the specimen heater so as to minimize heat leakage, technique for installing...Conductivity of Gadolinium Figure 3 shows another type of disagreement in experimental data from the literature. Here the two sets of thermal conductivity data...for gadolinium are for the same one piece of specimen measured in the same laboratory which S-" is one of the best known internationally, and published

Gadolinium Endohedral Metallofullerene-Based MRI Contrast Agents

NASA Astrophysics Data System (ADS)

Bolskar, Robert D.

With the ability to encapsulate and carry the highly paramagnetic Gd3+ ion, gadolinium endohedral metallofullerenes or "gadofullerenes" are being explored as alternatives to the chelate complexes that are currently used for contrast-enhanced magnetic resonance imaging (MRI). Reviewed here are the various water-soluble derivatives of the gadofullerenes Gd@C82, Gd@C60, and Gd3N@C80 that have been investigated as MRI contrast agents. The water proton r1 relaxivities of gadofullerenes can be more than an order of magnitude higher than those of clinically used chelate agents. Gadofullerene relaxivity mechanisms have been studied, and multiple factors are found to contribute to their high relaxivities. In vitro and in vivoT1-weighted MRI tests of gadofullerene derivatives have shown their utility as bright image-enhancing agents. The gadofullerene MRI contrast agents are a promising new and unique style of gadolinium carrier for advanced imaging applications, including cellular and molecular imaging.

Multimodal targeted high relaxivity thermosensitive liposome for in vivo imaging

NASA Astrophysics Data System (ADS)

Kuijten, Maayke M. P.; Hannah Degeling, M.; Chen, John W.; Wojtkiewicz, Gregory; Waterman, Peter; Weissleder, Ralph; Azzi, Jamil; Nicolay, Klaas; Tannous, Bakhos A.

2015-11-01

Liposomes are spherical, self-closed structures formed by lipid bilayers that can encapsulate drugs and/or imaging agents in their hydrophilic core or within their membrane moiety, making them suitable delivery vehicles. We have synthesized a new liposome containing gadolinium-DOTA lipid bilayer, as a targeting multimodal molecular imaging agent for magnetic resonance and optical imaging. We showed that this liposome has a much higher molar relaxivities r1 and r2 compared to a more conventional liposome containing gadolinium-DTPA-BSA lipid. By incorporating both gadolinium and rhodamine in the lipid bilayer as well as biotin on its surface, we used this agent for multimodal imaging and targeting of tumors through the strong biotin-streptavidin interaction. Since this new liposome is thermosensitive, it can be used for ultrasound-mediated drug delivery at specific sites, such as tumors, and can be guided by magnetic resonance imaging.

Kondo effect and enhanced magnetic properties in gadolinium functionalized carbon nanotube supramolecular complex.

PubMed

Ncube, S; Coleman, C; Strydom, A; Flahaut, E; de Sousa, A; Bhattacharyya, S

2018-05-23

We report on the enhancement of magnetic properties of multiwalled carbon nanotubes (MWNTs) functionalized with a gadolinium based supramolecular complex. By employing a newly developed synthesis technique we find that the functionalization method of the nanocomposite enhances the strength of magnetic interaction leading to a large effective moment of 15.79 µ B and non-superparamagnetic behaviour unlike what has been previously reported. Saturating resistance at low temperatures is fitted with the numerical renormalization group formula verifying the Kondo effect for magnetic impurities on a metallic electron system. Magnetoresistance shows devices fabricated from aligned gadolinium functionalized MWNTs (Gd-Fctn-MWNTs) exhibit spin-valve switching behaviour of up to 8%. This study highlights the possibility of enhancing magnetic interactions in carbon systems through chemical modification, moreover we demonstrate the rich physics that might be useful for developing spin based quantum computing elements based on one-dimensional (1D) channels.

HB-LINE ANION EXCHANGE PURIFICATION OF AFS-2 PLUTONIUM FOR MOX

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

Kyser, E. A.; King, W. D.

2012-07-31

Non-radioactive cerium (Ce) and radioactive plutonium (Pu) anion exchange column experiments using scaled HB-Line designs were performed to investigate the feasibility of using either gadolinium nitrate (Gd) or boric acid (B as H{sub 3}BO{sub 3}) as a neutron poison in the H-Canyon dissolution process. Expected typical concentrations of probable impurities were tested and the removal of these impurities by a decontamination wash was measured. Impurity concentrations are compared to two specifications - designated as Column A or Column B (most restrictive) - proposed for plutonium oxide (PuO{sub 2}) product shipped to the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). Usemore » of Gd as a neutron poison requires a larger volume of wash for the proposed Column A specification. Since boron (B) has a higher proposed specification and is more easily removed by washing, it appears to be the better candidate for use in the H-Canyon dissolution process. Some difficulty was observed in achieving the Column A specification due to the limited effectiveness that the wash step has in removing the residual B after ~4 BV's wash. However a combination of the experimental 10 BV's wash results and a calculated DF from the oxalate precipitation process yields an overall DF sufficient to meet the Column A specification. For those impurities (other than B) not removed by 10 BV's of wash, the impurity is either not expected to be present in the feedstock or process, or recommendations have been provided for improvement in the analytical detection/method or validation of calculated results. In summary, boron is recommended as the appropriate neutron poison for H-Canyon dissolution and impurities are expected to meet the Column A specification limits for oxide production in HB-Line.« less

HB-LINE ANION EXCHANGE PURIFICATION OF AFS-2 PLUTONIUM FOR MOX

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

Kyser, E.; King, W.

2012-04-25

Non-radioactive cerium (Ce) and radioactive plutonium (Pu) anion exchange column experiments using scaled HB-Line designs were performed to investigate the feasibility of using either gadolinium nitrate (Gd) or boric acid (B as H{sub 3}BO{sub 3}) as a neutron poison in the H-Canyon dissolution process. Expected typical concentrations of probable impurities were tested and the removal of these impurities by a decontamination wash was measured. Impurity concentrations are compared to two specifications - designated as Column A or Column B (most restrictive) - proposed for plutonium oxide (PuO{sub 2}) product shipped to the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). Usemore » of Gd as a neutron poison requires a larger volume of wash for the proposed Column A specification. Since boron (B) has a higher proposed specification and is more easily removed by washing, it appears to be the better candidate for use in the H-Canyon dissolution process. Some difficulty was observed in achieving the Column A specification due to the limited effectiveness that the wash step has in removing the residual B after {approx}4 BV's wash. However a combination of the experimental 10 BV's wash results and a calculated DF from the oxalate precipitation process yields an overall DF sufficient to meet the Column A specification. For those impurities (other than B) not removed by 10 BV's of wash, the impurity is either not expected to be present in the feedstock or process, or recommendations have been provided for improvement in the analytical detection/method or validation of calculated results. In summary, boron is recommended as the appropriate neutron poison for H-Canyon dissolution and impurities are expected to meet the Column A specification limits for oxide production in HB-Line.« less

Iodine I 131 and Pazopanib Hydrochloride in Treating Patients With Recurrent and/or Metastatic Thyroid Cancer Previously Treated With Iodine I 131 That Cannot Be Removed By Surgery

ClinicalTrials.gov

2015-11-04

Recurrent Thyroid Cancer; Stage IVA Follicular Thyroid Cancer; Stage IVA Papillary Thyroid Cancer; Stage IVB Follicular Thyroid Cancer; Stage IVB Papillary Thyroid Cancer; Stage IVC Follicular Thyroid Cancer; Stage IVC Papillary Thyroid Cancer

Glycoprotein and Glycan in Tissue and Blood Samples of Patients With Stage IB-IVA Cervical Cancer Undergoing Surgery to Remove Pelvic and Abdominal Lymph Nodes

ClinicalTrials.gov

2017-08-23

Cervical Adenocarcinoma; Cervical Adenosquamous Carcinoma; Cervical Small Cell Carcinoma; Cervical Squamous Cell Carcinoma, Not Otherwise Specified; Stage IB Cervical Cancer; Stage IIA Cervical Cancer; Stage IIB Cervical Cancer; Stage III Cervical Cancer; Stage IVA Cervical Cancer

Classification and regression tree (CART) analysis of endometrial carcinoma: Seeing the forest for the trees.

PubMed

Barlin, Joyce N; Zhou, Qin; St Clair, Caryn M; Iasonos, Alexia; Soslow, Robert A; Alektiar, Kaled M; Hensley, Martee L; Leitao, Mario M; Barakat, Richard R; Abu-Rustum, Nadeem R

2013-09-01

The objectives of the study are to evaluate which clinicopathologic factors influenced overall survival (OS) in endometrial carcinoma and to determine if the surgical effort to assess para-aortic (PA) lymph nodes (LNs) at initial staging surgery impacts OS. All patients diagnosed with endometrial cancer from 1/1993-12/2011 who had LNs excised were included. PALN assessment was defined by the identification of one or more PALNs on final pathology. A multivariate analysis was performed to assess the effect of PALNs on OS. A form of recursive partitioning called classification and regression tree (CART) analysis was implemented. Variables included: age, stage, tumor subtype, grade, myometrial invasion, total LNs removed, evaluation of PALNs, and adjuvant chemotherapy. The cohort included 1920 patients, with a median age of 62 years. The median number of LNs removed was 16 (range, 1-99). The removal of PALNs was not associated with OS (P=0.450). Using the CART hierarchically, stage I vs. stages II-IV and grades 1-2 vs. grade 3 emerged as predictors of OS. If the tree was allowed to grow, further branching was based on age and myometrial invasion. Total number of LNs removed and assessment of PALNs as defined in this study were not predictive of OS. This innovative CART analysis emphasized the importance of proper stage assignment and a binary grading system in impacting OS. Notably, the total number of LNs removed and specific evaluation of PALNs as defined in this study were not important predictors of OS. Copyright © 2013 Elsevier Inc. All rights reserved.

Adjuvant radiation therapy and lymphadenectomy in esophageal cancer: a SEER database analysis.

PubMed

Shridhar, Ravi; Weber, Jill; Hoffe, Sarah E; Almhanna, Khaldoun; Karl, Richard; Meredith, Kenneth

2013-08-01

This study seeks to determine the effects of postoperative radiation therapy and lymphadenectomy on survival in esophageal cancer. An analysis of patients with surgically resected esophageal cancer from the SEER database between 2004 and 2008 was performed to determine association of adjuvant radiation and lymph node dissection on survival. Survival curves were calculated according to the Kaplan-Meier method and log-rank analysis. Multivariate analysis (MVA) was performed by the Cox proportional hazard model. We identified 2109 patients who met inclusion criteria. Radiation was associated with increased survival in stage III patients (p = 0.005), no benefit in stage II (p = 0.075) and IV (p = 0.913) patients, and decreased survival in stage I patients (p < 0.0001). Univariate analysis revealed that radiation therapy was associated with a survival benefit node positive (N1) patients while it was associated with a detriment in survival for node negative (N0) patients. Removing >12 and >15 lymph nodes was associated with increased survival in N0 patients, while removing >8, >10, >12, >15, and >20 lymph nodes was associated with a survival benefit in N1 patients. MVA revealed that age, gender, tumor and nodal stage, tumor location, and number of lymph nodes removed were prognostic for survival in N0 patients. In N1 patients, MVA showed the age, tumor stage, number of lymph nodes removed, and radiation were prognostic for survival. The number of lymph nodes removed in esophageal cancer is associated with increased survival. The benefit of adjuvant radiation therapy on survival in esophageal cancer is limited to N1 patients.

Propranolol Hydrochloride in Treating Patients With Locally Recurrent or Metastatic Solid Tumors That Cannot Be Removed By Surgery

ClinicalTrials.gov

2017-11-27

Male Breast Cancer; Recurrent Melanoma; Stage IV Breast Cancer; Stage IV Melanoma; Stage IV Ovarian Epithelial Cancer; Stage IV Ovarian Germ Cell Tumor; Unspecified Adult Solid Tumor, Protocol Specific; Hepatocellular Carcinoma

Eribulin Mesylate and Gemcitabine Hydrochloride in Treating Patients With Metastatic Solid Tumors or Solid Tumors That Cannot be Removed by Surgery

ClinicalTrials.gov

2017-09-19

Adult Solid Neoplasm; Recurrent Ovarian Carcinoma; Recurrent Uterine Corpus Carcinoma; Stage III Ovarian Cancer; Stage III Uterine Corpus Cancer; Stage IV Ovarian Cancer; Stage IV Uterine Corpus Cancer

Method and apparatus for advanced staged combustion utilizing forced internal recirculation

DOEpatents

Rabovitser, Iosif K.; Knight, Richard A.; Cygan, David F.; Nester, Serguei; Abbasi, Hamid A.

2003-12-16

A method and apparatus for combustion of a fuel in which a first-stage fuel and a first-stage oxidant are introduced into a combustion chamber and ignited, forming a primary combustion zone. At least about 5% of the total heat output produced by combustion of the first-stage fuel and the first-stage oxidant is removed from the primary combustion zone, forming cooled first-stage combustion products. A portion of the cooled first-stage combustion products from a downstream region of the primary combustion zone is recirculated to an upstream region of primary combustion zone. A second-stage fuel is introduced into the combustion chamber downstream of the primary combustion zone and ignited, forming a secondary combustion zone. At least about 5% of the heat from the secondary combustion zone is removed. In accordance with one embodiment, a third-stage oxidant is introduced into the combustion chamber downstream of the secondary combustion zone, forming a tertiary combustion zone.

Sustainable multistage process for enhanced productivity of bioplastics from waste remediation through aerobic dynamic feeding strategy: Process integration for up-scaling.

PubMed

Amulya, K; Jukuri, Srinivas; Venkata Mohan, S

2015-01-01

Polyhydroxyalkanoates (PHA) production was evaluated in a multistage operation using food waste as a renewable feedstock. The first step involved the production of bio-hydrogen (bio-H2) via acidogenic fermentation. Volatile fatty acid (VFA) rich effluent from bio-H2 reactor was subsequently used for PHA production, which was carried out in two stages, Stage II (culture enrichment) and Stage III (PHA production). PHA-storing microorganisms were enriched in a sequencing batch reactor (SBR), operated at two different cycle lengths (CL-24; CL-12). Higher polymer recovery as well as VFA removal was achieved in CL-12 operation both in Stage II (16.3% dry cell weight (DCW); VFA removal, 84%) and Stage III (23.7% DCW; VFA removal, 88%). The PHA obtained was a co-polymer [P(3HB-co-3HV)] of PHB and PHV. The results obtained indicate that this integrated multistage process offers new opportunities to further leverage large scale PHA production with simultaneous waste remediation in the framework of biorefinery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Single-stage versus two-stage anaerobic fluidized bed bioreactors in treating municipal wastewater: Performance, foulant characteristics, and microbial community.

PubMed

Wu, Bing; Li, Yifei; Lim, Weikang; Lee, Shi Lin; Guo, Qiming; Fane, Anthony G; Liu, Yu

2017-03-01

This study examined the receptive performance, membrane foulant characteristics, and microbial community in the single-stage and two-stage anaerobic fluidized membrane bioreactor (AFMBR) treating settled raw municipal wastewater with the aims to explore fouling mechanisms and microbial community structure in both systems. Both AFMBRs exhibited comparable organic removal efficiency and membrane performances. In the single-stage AFMBR, less soluble organic substances were removed through biosorption by GAC and biodegradation than those in the two-stage AFMBR. Compared to the two-stage AFMBR, the formation of cake layer was the main cause of the observed membrane fouling in the single-stage AFMBR at the same employed flux. The accumulation rate of the biopolymers was linearly correlated with the membrane fouling rate. In the chemical-cleaned foulants, humic acid-like substances and silicon were identified as the predominant organic and inorganic fouants respectively. As such, the fluidized GAC particles might not be effective in removing these substances from the membrane surfaces. High-throughout pyrosequencing analysis further revealed that beta-Proteobacteria were predominant members in both AFMBRs, which contributed to the development of biofilms on the fluidized GAC and membrane surfaces. However, it was also noted that the abundance of the identified dominant in the membrane surface-associated biofilm seemed to be related to the permeate flux and reactor configuration. Copyright © 2016 Elsevier Ltd. All rights reserved.

Removal of hazardous gaseous pollutants from industrial flue gases by a novel multi-stage fluidized bed desulfurizer.

PubMed

Mohanty, C R; Adapala, Sivaji; Meikap, B C

2009-06-15

Sulfur dioxide and other sulfur compounds are generated as primary pollutants from the major industries such as sulfuric acid plants, cupper smelters, catalytic cracking units, etc. and cause acid rain. To remove the SO(2) from waste flue gas a three-stage counter-current multi-stage fluidized bed adsorber was developed as desulfurization equipment and operated in continuous bubbling fluidization regime for the two-phase system. This paper represents the desulfurization of gas mixtures by chemical sorption of sulfur dioxide on porous granular calcium oxide particles in the reactor at ambient temperature. The advantages of the multi-stage fluidized bed reactor are of high mass transfer and high gas-solid residence time that can enhance the removal of acid gas at low temperature by dry method. Experiments were carried out in the bubbling fluidization regime supported by visual observation. The effects of the operating parameters such as sorbent (lime) flow rate, superficial gas velocity, and the weir height on SO(2) removal efficiency in the multistage fluidized bed are reported. The results have indicated that the removal efficiency of the sulfur dioxide was found to be 65% at high solid flow rate (2.0 kg/h) corresponding to lower gas velocity (0.265 m/s), wier height of 70 mm and SO(2) concentration of 500 ppm at room temperature.

Coagulation removal of humic acid-stabilized carbon nanotubes from water by PACl: influences of hydraulic condition and water chemistry.

PubMed

Ma, Si; Liu, Changli; Yang, Kun; Lin, Daohui

2012-11-15

Discharged carbon nanotubes (CNTs) can adsorb the widely-distributed humic acid (HA) in aquatic environments and thus be stabilized. HA-stabilized CNTs can find their way into and challenge the potable water treatment system. This study investigated the efficiency of coagulation and sedimentation techniques in the removal of the HA-stabilized multi-walled carbon nanotubes (MWCNTs) using polyaluminum chloride (PACl) as a coagulant, with a focus on the effects of hydraulic conditions and water chemistry. Stirring speeds in the mixing and reacting stages were gradually changed to examine the effect of the hydraulic conditions on the removal rate. The stirring speed in the reacting stage affected floc formation and thereby had a greater impact on the removal rate than the stirring speed in the mixing stage. Water chemistry factors such as pH and ionic strength had a significant effect on the stability of MWCNT suspension and the removal efficiency. Low pH (4-7) was favorable for saving the coagulant and maintaining high removal efficiency. High ionic strength facilitated the destabilization of the HA-stabilized MWCNTs and thereby lowered the required PACl dosage for the coagulation. However, excessively high ionic strength (higher than the critical coagulation concentration) decreased the maximum removal rate, probably by inhibiting ionic activity of PACl hydrolyzate in water. These results are expected to shed light on the potential improvement of coagulation removal of aqueous stabilized MWCNTs in water treatment systems. Copyright © 2012 Elsevier B.V. All rights reserved.

Pilot investigation of two-stage biofiltration for removal of natural organic matter in drinking water treatment.

PubMed

Fu, Jie; Lee, Wan-Ning; Coleman, Clark; Meyer, Melissa; Carter, Jason; Nowack, Kirk; Huang, Ching-Hua

2017-01-01

A pilot study employing two parallel trains of two-stage biofiltration, i.e., a sand/anthracite (SA) biofilter followed by a biologically-active granular activated carbon (GAC) contactor, was conducted to test the efficiency, feasibility and stability of biofiltration for removing natural organic matter (NOM) after coagulation in a drinking water treatment plant. Results showed the biofiltration process could effectively remove turbidity (<0.1 NTU in all effluents) and NOM (>24% of dissolved organic carbon (DOC), >57% of UV 254 , and >44% of SUVA 254 ), where the SA biofilters showed a strong capacity for turbidity removal, while the GAC contactors played the dominant role in NOM removal. The vertical profile of water quality in the GAC contactors indicated the middle-upper portion was the critical zone for the removal of NOM, where relatively higher adsorption and enhanced biological removal were afforded. Fluorescence excitation-emission matrix (EEM) analysis of NOM showed that the GAC contactors effectively decreased the content of humic-like component, while protein-like component was refractory for the biofiltration process. Nutrients (NH 4 -N and PO 4 -P) supplementation applied upstream of one of the two-stage biofiltration trains (called engineered biofiltration) stimulated the growth of microorganisms, and showed a modest effect on promoting the biological removal of small non-aromatic compositions in NOM. Redundancy analysis (RDA) indicated influent UV 254 was the most explanatory water quality parameter for GAC contactors' treatment performance, and a high load of UV 254 would result in significantly reduced removals of UV 254 and SUVA 254 . Copyright © 2016 Elsevier Ltd. All rights reserved.

A simple approach to optimal control of invasive species.

PubMed

Hastings, Alan; Hall, Richard J; Taylor, Caz M

2006-12-01

The problem of invasive species and their control is one of the most pressing applied issues in ecology today. We developed simple approaches based on linear programming for determining the optimal removal strategies of different stage or age classes for control of invasive species that are still in a density-independent phase of growth. We illustrate the application of this method to the specific example of invasive Spartina alterniflora in Willapa Bay, WA. For all such systems, linear programming shows in general that the optimal strategy in any time step is to prioritize removal of a single age or stage class. The optimal strategy adjusts which class is the focus of control through time and can be much more cost effective than prioritizing removal of the same stage class each year.

Sequential biofiltration - A novel approach for enhanced biological removal of trace organic chemicals from wastewater treatment plant effluent.

PubMed

Müller, Johann; Drewes, Jörg E; Hübner, Uwe

2017-12-15

Recent studies revealed the benefits of oligotrophic and oxic conditions for the biological removal of many trace organic chemicals (TOrCs) during soil-aquifer treatment. These findings indicate an unused tuning potential that might also be applicable in engineered biofiltration systems with drastically reduced hydraulic retention times for an enhanced mitigation of TOrCs during wastewater treatment. This study introduces the novel approach of sequential biofiltration (SBF) for the advanced treatment of secondary effluent using two granular media filters operated in series with an intermediate aeration step aiming for oxic and oligotrophic conditions in the second filter stage. Results from the experiments conducted at pilot-scale confirm a reduced substrate availability and predominantly oxic conditions in the second filter stage of the SBF setup. An increased removal of several TOrCs was observed in an SBF system as compared to a conventional single-stage biofiltration unit operated at the same overall empty bed contact time (EBCT). Short-term tests with varying EBCTs in the first filter stage revealed a high degree of system robustness of TOrC mitigation when confronted with sudden hydraulic load variations. Higher removal of several TOrCs at increased EBCTs in the second filter stage indicates that EBCT might play a crucial role for the degradation of certain compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal sulfide sorbents

DOEpatents

Ayala, Raul E.; Gal, Eli

1995-01-01

A process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal-sulfur compound. Spent metal-sulfur compound is regenerated to re-usable metal oxide by moving a bed of spent metal-sulfur compound progressively through a single regeneration vessel having a first and second regeneration stage and a third cooling and purging stage. The regeneration is carried out and elemental sulfur is generated in the first stage by introducing a first gas of sulfur dioxide which contains oxygen at a concentration less than the stoichiometric amount required for complete oxidation of the spent metal-sulfur compound. A second gas containing sulfur dioxide and excess oxygen at a concentration sufficient for complete oxidation of the partially spent metal-sulfur compound, is introduced into the second regeneration stage. Gaseous sulfur formed in the first regeneration stage is removed prior to introducing the second gas into the second regeneration stage. An oxygen-containing gas is introduced into the third cooling and purging stage. Except for the gaseous sulfur removed from the first stage, the combined gases derived from the regeneration stages which are generally rich in sulfur dioxide and lean in oxygen, are removed from the regenerator as an off-gas and recycled as the first and second gas into the regenerator. Oxygen concentration is controlled by adding air, oxygen-enriched air or pure oxygen to the recycled off-gas.

An innovative attached-growth biological system for purification of pond water.

PubMed

Chang, Chia-Yuan; Chang, Jing-Song; Chen, Chien-Min; Chiemchaisri, Chart; Vigneswaran, Saravanamuthu

2010-03-01

This study applied the non-woven material from used diaper as the carrier for bio-film process to purify the recycled water from a landscape pond at the Tainan City Municipal Culture Center (TCMCC), Taiwan. An on-site system was installed and the experiment was accomplished through three stages in 192 days with different time periods of 70 days, 63 days, and 59 days, respectively. The results showed that the non-woven media is functional for SS removal. The average SS removal of stages 1, 2, and 3 were 91%, 96%, and 95%, respectively. The highest SCOD removal efficiency of 90% occurred at stage 3. A significant color improvement of the pond water was achieved through this non-woven bio-carrier treatment system. Whole system can be without any maintenance for 139 days. The result indicated that the non-woven medium system was with a great potential in treating and recycling the pond water with stable operation and satisfactory removal performance. 2009 Elsevier Ltd. All rights reserved.

Nuclear reactor with makeup water assist from residual heat removal system

DOEpatents

Corletti, Michael M.; Schulz, Terry L.

1993-01-01

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path.

Nuclear reactor with makeup water assist from residual heat removal system

DOEpatents

Corletti, M.M.; Schulz, T.L.

1993-12-07

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path. 2 figures.

Current German Laser and Quantum Optics Research Reviewed at the 50th Annual Meeting of the Physikalische Gesellschaft.

DTIC Science & Technology

1986-04-23

Physics, Munster In the area of generating useable University) studied an interesting de- coherent high-frequency radiation, I vice, a silicon Fabry ...has a substantial crys- tingen) described studies with Cr- plus tal growing capability. One paper from Nd-doped gadolinium -scandium-gallium the Hamburg...institute, read by J. Drube, garnets (GSGG), and also with Cr-doped reported on Xe-flashlamp-pumped Cr:CSA(; % gadolinium -scandium-aluminum garnets

Crystallography, Spectroscopic Analysis, and Lasing Properties of Nd(3+) :Y3Sc2Al3O12

DTIC Science & Technology

1989-12-01

aluminum garnet (GSAG), are formed from more stable constitu- ent oxides than gallium-containing materials, 2. Experimental Results and such as gadolinium ...the which an assessment can be made regarding aluminum -based systems, such as YAG, YSAG, Nd:YSAG as a laser material. or gadolinium scandium...Structure oxidation state variation or oxygen vacancies, and this problem is greatly reduced in alumi- Yttrium scandium aluminum garnet be- nate systems

High-pressure high-temperature phase diagram of gadolinium studied using a boron-doped heater anvil

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

Montgomery, J. M.; Samudrala, G. K.; Vohra, Y. K.

A boron-doped designer heater anvil is used in conjunction with powder x-ray diffraction to collect structural information on a sample of quasi-hydrostatically loaded gadolinium metal up to pressures above 8 GPa and 600 K. The heater anvil consists of a natural diamond anvil that has been surface modified with a homoepitaxially grown chemical-vapor-deposited layer of conducting boron-doped diamond, and is used as a DC heating element. Internally insulating both diamond anvils with sapphire support seats allows for heating and cooling of the high-pressure area on the order of a few tens of seconds. This device is then used to scan the phasemore » diagram of the sample by oscillating the temperature while continuously increasing the externally applied pressure and collecting in situ time-resolved powder diffraction images. In the pressure-temperature range covered in this experiment, the gadolinium sample is observed in its hcp, αSm, and dhcp phases. Under this temperature cycling, the hcp → αSm transition proceeds in discontinuous steps at points along the expected phase boundary. From these measurements (representing only one hour of synchrotron x-ray collection time), a single-experiment equation of state and phase diagram of each phase of gadolinium is presented for the range of 0–10 GPa and 300–650 K.« less

Saline as the Sole Contrast Agent for Successful MRI-guided Epidural Injections

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

Deli, Martin, E-mail: martin.deli@web.de; Fritz, Jan, E-mail: jfritz9@jhmi.edu; Mateiescu, Serban, E-mail: mateiescu@microtherapy.de

Purpose. To assess the performance of sterile saline solution as the sole contrast agent for percutaneous magnetic resonance imaging (MRI)-guided epidural injections at 1.5 T. Methods. A retrospective analysis of two different techniques of MRI-guided epidural injections was performed with either gadolinium-enhanced saline solution or sterile saline solution for documentation of the epidural location of the needle tip. T1-weighted spoiled gradient echo (FLASH) images or T2-weighted single-shot turbo spin echo (HASTE) images visualized the test injectants. Methods were compared by technical success rate, image quality, table time, and rate of complications. Results. 105 MRI-guided epidural injections (12 of 105 withmore » gadolinium-enhanced saline solution and 93 of 105 with sterile saline solution) were performed successfully and without complications. Visualization of sterile saline solution and gadolinium-enhanced saline solution was sufficient, good, or excellent in all 105 interventions. For either test injectant, quantitative image analysis demonstrated comparable high contrast-to-noise ratios of test injectants to adjacent body substances with reliable statistical significance levels (p < 0.001). The mean table time was 22 {+-} 9 min in the gadolinium-enhanced saline solution group and 22 {+-} 8 min in the saline solution group (p = 0.75). Conclusion. Sterile saline is suitable as the sole contrast agent for successful and safe percutaneous MRI-guided epidural drug delivery at 1.5 T.« less

[Combined use of contrast media containing iodine and gadolinium for imaging and intervention : A hitherto widely ignored topic in radiological practice].

PubMed

Golder, W

2012-02-01

The synchronous use of chemically different contrast media in the same body compartment is a challenge for the radiologist, whether it is scheduled or unexpected. However, to inject contrast media containing iodine and gadolinium at the same time can be a prerequisite for the examination of several organs or organ systems. Unlike other topics of contrast-enhanced imaging procedures, the difficulties encountered with double contrast injections have been widely ignored in the literature. In the absence of reliable data from experimental and clinical studies the radiologist is dependent on case reports, information provided by the contrast media manufacturers, personal communications, mostly scanty personal experiences and a skilful time management, in order to overcome the situation. Only the combination of X-ray, computed tomography and magnetic resonance arthrography can be performed without another thought. However, the more or less synchronous vascular application of contrast media containing iodine and gadolinium requires vigilance. The more seriously ill the patient is, the more caution is advised even if the decision on the combined administration has to be reached urgently. The following overview gives a description of the properties of contrast media containing iodine and gadolinium as far as interactions following simultaneous administration are concerned. Subsequently, the clinically relevant situations and constellations are outlined and analyzed.

Convection-enhanced delivery of MANF--volume of distribution analysis in porcine putamen and substantia nigra.

PubMed

Barua, N U; Bienemann, A S; Woolley, M; Wyatt, M J; Johnson, D; Lewis, O; Irving, C; Pritchard, G; Gill, S

2015-10-15

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a 20kDa human protein which has both neuroprotective and neurorestorative activity on dopaminergic neurons and therefore may have application for the treatment of Parkinson's Disease. The aims of this study were to determine the translational potential of convection-enhanced delivery (CED) of MANF for the treatment of PD by studying its distribution in porcine putamen and substantia nigra and to correlate histological distribution with co-infused gadolinium-DTPA using real-time magnetic resonance imaging. We describe the distribution of MANF in porcine putamen and substantia nigra using an implantable CED catheter system using co-infused gadolinium-DTPA to allow real-time MRI tracking of infusate distribution. The distribution of gadolinium-DTPA on MRI correlated well with immunohistochemical analysis of MANF distribution. Volumetric analysis of MANF IHC staining indicated a volume of infusion (Vi) to volume of distribution (Vd) ratio of 3 in putamen and 2 in substantia nigra. This study confirms the translational potential of CED of MANF as a novel treatment strategy in PD and also supports the co-infusion of gadolinium as a proxy measure of MANF distribution in future clinical studies. Further study is required to determine the optimum infusion regime, flow rate and frequency of infusions in human trials. Copyright © 2015 Elsevier B.V. All rights reserved.

T1 relaxivity of core-encapsulated gadolinium liposomal contrast agents--effect of liposome size and internal gadolinium concentration.

PubMed

Ghaghada, Ketan; Hawley, Catherine; Kawaji, Keigo; Annapragada, Ananth; Mukundan, Srinivasan

2008-10-01

Long circulating core-encapsulated gadolinium (CE-Gd) liposomal nanoparticles that have surface conjugated polyethylene glycol are a promising platform technology for use as blood pool T1-based magnetic resonance (MR) contrast agents. The objective of this study was to investigate the effect of liposome size and internal (core) Gd concentration on the T1 relaxivity of CE-Gd liposomes. Twelve different liposomal formulations were synthesized and characterized, resulting in a size (50, 100, 200, and 400 nm) and core Gd-concentration (200, 350, and 500 mM) "matrix" of test samples. Subsequently, CE-Gd liposomes were diluted in deionized water (four diluted samples) and molar T1 relaxivity (r1) measurements were performed at 2- and 7-T MR field strengths. The r1 of CE-Gd liposomes was inversely related to the liposome size. The largest change in r1 was observed between liposomes that were extruded through 50- and 100-nm filter membranes. At both field strengths, the variation in internal gadolinium concentration did not show any significant correlation (alpha < or = 0.05) with r1. The size of CE-Gd liposomal nanoparticles significantly affects the T1 relaxivity. An inverse relation was observed between liposome size and T1 relaxivity. The T1 relaxivity did not change significantly with core Gd concentration over the measured concentration range.

Gadolinium prevents high airway pressure-induced permeability increases in isolated rat lungs.

PubMed

Parker, J C; Ivey, C L; Tucker, J A

1998-04-01

To determine the initial signaling event in the vascular permeability increase after high airway pressure injury, we compared groups of lungs ventilated at different peak inflation pressures (PIPs) with (gadolinium group) and without (control group) infusion of 20 microM gadolinium chloride, an inhibitor of endothelial stretch-activated cation channels. Microvascular permeability was assessed by using the capillary filtration coefficient (Kfc), a measure of capillary hydraulic conductivity. Kfc was measured after ventilation for 30-min periods with 7, 20, and 30 cmH2O PIP with 3 cmH2O positive end-expiratory pressure and with 35 cmH2O PIP with 8 cmH2O positive end-expiratory pressure. In control lungs, Kfc increased significantly to 1.8 and 3.7 times baseline after 30 and 35 cmH2O PIP, respectively. In the gadolinium group, Kfc was unchanged from baseline (0.060 +/- 0.010 ml . min-1 . cmH2O-1 . 100 g-1) after any PIP ventilation period. Pulmonary vascular resistance increased significantly from baseline in both groups before the last Kfc measurement but was not different between groups. These results suggest that microvascular permeability is actively modulated by a cellular response to mechanical injury and that stretch-activated cation channels may initiate this response through increases in intracellular calcium concentration.

In vivo evaluation of neutron capture therapy effectivity using calcium phosphate-based nanoparticles as Gd-DTPA delivery agent.

PubMed

Dewi, Novriana; Mi, Peng; Yanagie, Hironobu; Sakurai, Yuriko; Morishita, Yasuyuki; Yanagawa, Masashi; Nakagawa, Takayuki; Shinohara, Atsuko; Matsukawa, Takehisa; Yokoyama, Kazuhito; Cabral, Horacio; Suzuki, Minoru; Sakurai, Yoshinori; Tanaka, Hiroki; Ono, Koji; Nishiyama, Nobuhiro; Kataoka, Kazunori; Takahashi, Hiroyuki

2016-04-01

A more immediate impact for therapeutic approaches of current clinical research efforts is of major interest, which might be obtained by developing a noninvasive radiation dose-escalation strategy, and neutron capture therapy represents one such novel approach. Furthermore, some recent researches on neutron capture therapy have focused on using gadolinium as an alternative or complementary for currently used boron, taking into account several advantages that gadolinium offers. Therefore, in this study, we carried out feasibility evaluation for both single and multiple injections of gadolinium-based MRI contrast agent incorporated in calcium phosphate nanoparticles as neutron capture therapy agent. In vivo evaluation was performed on colon carcinoma Col-26 tumor-bearing mice irradiated at nuclear reactor facility of Kyoto University Research Reactor Institute with average neutron fluence of 1.8 × 10(12) n/cm(2). Antitumor effectivity was evaluated based on tumor growth suppression assessed until 27 days after neutron irradiation, followed by histopathological analysis on tumor slice. The experimental results showed that the tumor growth of irradiated mice injected beforehand with Gd-DTPA-incorporating calcium phosphate-based nanoparticles was suppressed up to four times higher compared to the non-treated group, supported by the results of histopathological analysis. The results of antitumor effectivity observed on tumor-bearing mice after neutron irradiation indicated possible effectivity of gadolinium-based neutron capture therapy treatment.

Nivolumab and Ipilimumab With or Without Sargramostim in Treating Patients With Stage III-IV Melanoma That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-06-20

Recurrent Melanoma of the Skin; Stage III Cutaneous Melanoma AJCC v7; Stage IIIA Cutaneous Melanoma AJCC v7; Stage IIIB Cutaneous Melanoma AJCC v7; Stage IIIC Cutaneous Melanoma AJCC v7; Stage IV Cutaneous Melanoma AJCC v6 and v7

Parallel magnetic resonance imaging using coils with localized sensitivities.

PubMed

Goldfarb, James W; Holland, Agnes E

2004-09-01

The purpose of this study was to present clinical examples and illustrate the inefficiencies of a conventional reconstruction using a commercially available phased array coil with localized sensitivities. Five patients were imaged at 1.5 T using a cardiac-synchronized gadolinium-enhanced acquisition and a commercially available four-element phased array coil. Four unique sets of images were reconstructed from the acquired k-space data: (a) sum-of-squares image using four elements of the coil; localized sum-of-squares images from the (b) anterior coils and (c) posterior coils and a (c) local reconstruction. Images were analyzed for artifacts and usable field-of-view. Conventional image reconstruction produced images with fold-over artifacts in all cases spanning a portion of the image (mean 90 mm; range 36-126 mm). The local reconstruction removed fold-over artifacts and resulted in an effective increase in the field-of-view (mean 50%; range 20-70%). Commercially available phased array coils do not always have overlapping sensitivities. Fold-over artifacts can be removed using an alternate reconstruction method. When assessing the advantages of parallel imaging techniques, gains achieved using techniques such as SENSE and SMASH should be gauged against the acquisition time of the localized method rather than the conventional sum-of-squares method.

Palatal insufficiency as isolated sign of GQ1b antibody syndrome.

PubMed

Verhelst, Helene; Maes, Michaela; Deblaere, Karel; Van Coster, Rudy

2011-04-01

Antiganglioside GQ1b antibodies mediate a continuum of disorders with overlapping features, fostering the concept of anti-GQ1b antibody syndrome. We present a patient whose palatal insufficiency was the only clinical sign of postinfectious GQ1b antibody syndrome. Cerebral magnetic resonance imaging confirmed involvement of the glossopharyngeal nerve and vagus nerve bilaterally, revealing gadolinium enhancement of both nerves bilaterally and thickening of the left nervus vagus. Magnetic resonance imaging may help in diagnosing postinfectious GQ1b antibody syndrome, especially at early stages and in monosymptomatic patients. Early diagnosis may lead to early therapy, resulting in a milder disease course by preventing further deterioration leading to the ataxia and ophthalmoplegia usually observed in patients with postinfectious GQ1b antibody syndrome. Copyright © 2011 Elsevier Inc. All rights reserved.

Sacral myeloradiculitis complicating genital herpes in a HIV-infected patient.

PubMed

Corral, I; Quereda, C; Navas, E; Pérez-Elias, M J; Jover, F; Moreno, S

2005-02-01

Myeloradiculitis is a rare neurological complication of herpes simplex type 2 (HSV-2) infection, frequently associated with a fatal outcome. Among patients with HIV infection, HSV-2 myeloradiculitis has occasionally been reported, always associated with advanced immunosuppression and AIDS. We report a patient with HIV infection but no history of previous opportunistic infections, who developed sacral myeloradiculitis immediately after an episode of genital herpes. Magnetic resonance imaging with gadolinium showed necrotizing myelitis in the conus medullaris and enhancement of sacral roots. CD4 lymphocyte count was 530/mm3. Other possible causes of myeloradiculitis in HIV-infected patients were appropriately excluded. Acyclovir therapy resulted in partial clinical improvement. This report shows that myeloradiculitis as a complication of genital herpes may occur in the early stages of HIV infection and may have a favourable outcome with antiviral treatment.

Combined inhibition of autophagy and caspases fails to prevent developmental nurse cell death in the Drosophila melanogaster ovary.

PubMed

Peterson, Jeanne S; McCall, Kimberly

2013-01-01

During the final stages of Drosophila melanogaster oogenesis fifteen nurse cells, sister cells to the oocyte, degenerate as part of normal development. This process involves at least two cell death mechanisms, caspase-dependent cell death and autophagy, as indicated by apoptosis and autophagy markers. In addition, mutations affecting either caspases or autophagy partially reduce nurse cell removal, leaving behind end-stage egg chambers with persisting nurse cell nuclei. To determine whether apoptosis and autophagy work in parallel to degrade and remove these cells as is the case with salivary glands during pupariation, we generated mutants doubly affecting caspases and autophagy. We found no significant increase in either the number of late stage egg chambers containing persisting nuclei or in the number of persisting nuclei per egg chamber in the double mutants compared to single mutants. These findings suggest that there is another cell death mechanism functioning in the ovary to remove all nurse cell remnants from late stage egg chambers.

A new multiple-stage electrocoagulation process on anaerobic digestion effluent to simultaneously reclaim water and clean up biogas.

PubMed

Liu, Zhiguo; Stromberg, David; Liu, Xuming; Liao, Wei; Liu, Yan

2015-03-21

A new multiple-stage treatment process was developed via integrating electrocoagulation with biogas pumping to simultaneously reclaim anaerobic digestion effluent and clean up biogas. The 1st stage of electrocoagulation treatment under the preferred reaction condition led to removal efficiencies of 30%, 81%, 37% and >99.9% for total solids, chemical oxygen demand, total nitrogen and total phosphorus, respectively. Raw biogas was then used as a reactant and pumped into the effluent to simultaneously neutralize pH of the effluent and remove H2S in the biogas. The 2nd stage of electrocoagulation treatment on the neutralized effluent showed that under the selected reaction condition, additional 60% and 10% of turbidity and chemical oxygen demand were further removed. The study concluded a dual-purpose approach for the first time to synergistically combine biogas purification and water reclamation for anaerobic digestion system, which well addresses the downstream challenges of anaerobic digestion technology. Copyright © 2014 Elsevier B.V. All rights reserved.

Structural, kinetic, and thermodynamic characterization of the interconverting isomers of MS-325, a gadolinium(III)-based magnetic resonance angiography contrast agent.

PubMed

Tyeklar, Zoltan; Dunham, Stephen U; Midelfort, Katarina; Scott, Daniel M; Sajiki, Hirano; Ong, Karen; Lauffer, Randall B; Caravan, Peter; McMurry, Thomas J

2007-08-06

The amphiphilic gadolinium complex MS-325 ((trisodium-{(2-(R)-[(4,4-diphenylcyclohexyl) phosphonooxymethyl] diethylenetriaminepentaacetato) (aquo)gadolinium(III)}) is a contrast agent for magnetic resonance angiography (MRA). MS-325 comprises a GdDTPA core with an appended phosphodiester moiety linked to a diphenylcyclohexyl group to facilitate noncovalent binding to serum albumin and extension of the plasma half-life in vivo. The chiral DTPA ligand (R) was derived from L-serine, and upon complexation with gadolinium, forms two interconvertible diastereomers, denoted herein as isomers A and B. X-ray crystallography of the tris(ethylenediamine)cobalt(III) salt derivative of isomer A revealed a structure in the polar acentric space group P32. The structure consisted of three independent molecules of the gadolinium complex in the asymmetric unit along with three Delta-[Co(en)3]3+ cations, and it represents an unusual example of spontaneous Pasteur resolution of the cobalt cation. The geometry of the coordination core was best described as a distorted trigonal prism, and the final R factor was 5.6%. The configuration of the chiral central nitrogen of the DTPA core was S. The Gd-water (2.47-2.48 A), the Gd-acetate oxygens (2.34-2.42 A), and the Gd-N bond distances (central N, 2.59-2.63 A; terminal N, 2.74-2.80 A) were similar to other reported GdDTPA structures. The structurally characterized single crystal was one of two interconvertable diastereomers (isomers A and B) that equilibrated to a ratio of 1.81 to 1 at pH 7.4 and were separable at elevated pH by ion-exchange chromatography. The rate of isomerization was highly pH dependent: k1 = (1.45 +/- 0.08) x 102[H+] + (4.16 +/- 0.30) x 105[H+]2; k-1 = (2.57 +/- 0.17) x 102[H+] + (7.54 +/- 0.60) x 105[H+]2.

Image-guided convection-enhanced delivery of muscimol to the primate brain

PubMed Central

Heiss, John D.; Walbridge, Stuart; Asthagiri, Ashok R.; Lonser, Russell R.

2009-01-01

Object Muscimol is a potent γ-aminobutyric acid-A receptor agonist (GABAA) that temporarily and selectively suppresses neurons. Targeted muscimol-suppression of neuronal structures could provide insight into the pathophysiology and treatment of a variety of neurologic disorders. To determine if muscimol delivered to the brain by convection-enhanced delivery (CED) could be monitored using a co-infused surrogate magnetic resonance (MR)-imaging tracer, we perfused the striata of primates with tritiated muscimol and gadolinium-DTPA. Methods Three primates underwent convective co-infusion of 3H-muscimol (0.8 μM) and gadolinium-DTPA (−5 mM) into the bilateral striata. Primates underwent serial MR-imaging during infusion and animals were sacrificed immediately after infusion. Post-mortem quantitative autoradiography and histological analysis was performed. Results MR-imaging revealed that infusate (tritiated muscimol and gadolinium-DTPA) distribution was clearly discernible from the non-infused parenchyma. Real-time MR-imaging of the infusion revealed the precise region of anatomic perfusion in each animal. Imaging analysis during infusion revealed that the distribution volume of infusate linearly increased (R=0.92) with volume of infusion. Overall, the mean (±S.D.) volume of distribution to volume of infusion ratio was 8.2±1.3. Autoradiographic analysis revealed that MR-imaging of gadolinium-DTPA closely correlated with the distribution of 3H-muscimol and precisely estimated its volume of distribution (mean difference in volume of distribution, 7.4%). Quantitative autoradiograms revealed that muscimol was homogeneously distributed over the perfused region in a square-shaped concentration profile. Conclusions Muscimol can be effectively delivered to clinically relevant volumes of the primate brain. Moreover, the distribution of muscimol can be tracked by co-infusion of gadolinium-DTPA using MR-imaging. The ability to accurately monitor and control the anatomic extent of muscimol distribution during its convection-enhanced delivery will enhance safety, permit correlations of muscimol distribution with clinical effect, and should lead to an improved understanding of the pathophysiologic processes underlying a variety of neurologic disorders. PMID:19715424

Effect of Cu2+ substitution on the structural, magnetic and electrical properties of gadolinium orthoferrite

NASA Astrophysics Data System (ADS)

Sai Vandana, C.; Hemalatha Rudramadevi, B.

2018-04-01

The pure and copper (Cu) substituted Gadolinium orthoferrites, GdFeO3, GdCu0.1Fe0.9O3, GdCu0.2Fe0.8O3 and GdCu0.3Fe0.7O3 were synthesized by conventional solid state method. The structural, morphological, dielectric, magnetic and impedance properties of Cu substituted Gadolinium orthoferrites have been investigated. The crystallographic phase as well as the substitution of Cu2+ ions in the lattice of GdFeO3 is confirmed from the x-ray diffraction patterns. The Fourier transform infrared spectra exhibit two prominent fundamental absorption peaks at ∼417 cm‑1 and 545 cm‑1. These bands are related to inherent stretching vibrations of metals at octahedral and tetrahedral sites respectively. The coercivity (Hc) and saturation magnetization (Ms) of the synthesized samples at different temperatures were determined from the hysteresis plots. Higher coercive values, 598 Oe and 600 Oe were achieved in GdCu0.1Fe0.9O3 ferrites compared to 527 Oe and 360 Oe in pure GdFeO3 at room temperature (300 K) and low temperature (20 k) respectively. Dielectric dispersion has been observed for gadolinium ferrite samples with Maxwell–Wagner type interfacial polarization. The decrease of dielectric constant and dielectric loss tangent with an increase in frequency was observed. The conduction due to charge hopping between localized states was confirmed from AC conductivity measurements. The composition dependent cationic distributions estimated from XRD, magnetic and electrical studies are in good agreement with each other. The achieved results indicate that the substitution of Cu in gadolinium orthoferrite strongly influences the crystal structure, magnetic and electrical properties thereby making them suitable as multiple state memory devices, transducers, electronic field controlled ferromagnetic resonance devices and spintronic devices.

Gadolinium embedded iron oxide nanoclusters as T1-T2 dual-modal MRI-visible vectors for safe and efficient siRNA delivery

NASA Astrophysics Data System (ADS)

Wang, Xiaoyong; Zhou, Zijian; Wang, Zhiyong; Xue, Yunxin; Zeng, Yun; Gao, Jinhao; Zhu, Lei; Zhang, Xianzhong; Liu, Gang; Chen, Xiaoyuan

2013-08-01

This report illustrates a new strategy of designing a T1-T2 dual-modal magnetic resonance imaging (MRI)-visible vector for siRNA delivery and MRI. Hydrophobic gadolinium embedded iron oxide (GdIO) nanocrystals are self-assembled into nanoclusters in the water phase with the help of stearic acid modified low molecular weight polyethylenimine (stPEI). The resulting water-dispersible GdIO-stPEI nanoclusters possess good stability, monodispersity with narrow size distribution and competitive T1-T2 dual-modal MR imaging properties. The nanocomposite system is capable of binding and delivering siRNA for knockdown of a gene of interest while maintaining its magnetic properties and biocompatibility. This new gadolinium embedded iron oxide nanocluster provides an important platform for safe and efficient gene delivery with non-invasive T1-T2 dual-modal MRI monitoring capability.This report illustrates a new strategy of designing a T1-T2 dual-modal magnetic resonance imaging (MRI)-visible vector for siRNA delivery and MRI. Hydrophobic gadolinium embedded iron oxide (GdIO) nanocrystals are self-assembled into nanoclusters in the water phase with the help of stearic acid modified low molecular weight polyethylenimine (stPEI). The resulting water-dispersible GdIO-stPEI nanoclusters possess good stability, monodispersity with narrow size distribution and competitive T1-T2 dual-modal MR imaging properties. The nanocomposite system is capable of binding and delivering siRNA for knockdown of a gene of interest while maintaining its magnetic properties and biocompatibility. This new gadolinium embedded iron oxide nanocluster provides an important platform for safe and efficient gene delivery with non-invasive T1-T2 dual-modal MRI monitoring capability. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr02797j

Pembrolizumab and Capecitabine in Treating Patients With Locally Advanced or Metastatic Triple Negative or Hormone-Refractory Breast Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-03-15

Estrogen Receptor Negative; HER2/Neu Negative; Progesterone Receptor Negative; Recurrent Breast Carcinoma; Stage III Breast Cancer; Stage IIIA Breast Cancer; Stage IIIB Breast Cancer; Stage IIIC Breast Cancer; Stage IV Breast Cancer; Triple-Negative Breast Carcinoma

Neurosarcoidosis--demonstration of meningeal disease by gadolinium enhanced magnetic resonance imaging.

PubMed Central

Khaw, K T; Manji, H; Britton, J; Schon, F

1991-01-01

Arriving at a firm diagnosis of neurosarcoidosis continues to pose serious problems, particularly when evidence of granulomatous disease outside the nervous system is lacking. The commonest mode of presentation of neurosarcoidosis is with cranial nerve palsies. Two cases of presumed neurosarcoidosis with cranial nerve palsies showed clear evidence of focal meningeal disease on gadolinium-DTPA enhanced MRI brain scans. Although not specific for sarcoidosis, this technique may be very useful in aiding the diagnosis in suspected cases. Images PMID:1880510

Tunable Microwave Transversal Filters and Dispersive Delay Lines Based on Oblique Incidence Reflection of Magnetostatic Wave Propagating in Epitaxial Garnets.

DTIC Science & Technology

1986-09-30

surface. Ferromagnetic resonance measurements on Ion implanted garnet films (2.18, 2.19) have confirmed that the principal effects of ion implantation...Yttrium Iro Garnet (Y 3FesO1 2 ) films used in the experiments were grown or one Inch polished [111] oriented Gadolinium Gallium Garnet (GGG) wafers, by...Yttrium Iron Garnet ) films grown on 0.5mm thick substrate of GGG (Gadolinium Gallium Garnet ). Samples were angle lapped to optimize coupling into and

Feasibility analysis of reciprocating magnetic heat pumps

NASA Technical Reports Server (NTRS)

Larson, A. V.; Hartley, J. G.; Shelton, S. V.; Smith, M. M.

1986-01-01

The conceptual design selected for detailed system analysis and optimization is the reciprocating gadolinium core in a regenerative fluid column within the bore of a superconducting magnet. The thermodynamic properties of gadolinium are given. A computerized literature search for relevant papers was conducted and is being analyzed. Contact was made with suppliers of superconducting magnets and accessories, magnetic materials, and various types of hardware. A description of the model for the thermal analysis of the core and regenerator fluids is included.

Quality Control and Nondestructive Evaluation Techniques for Composites. Part 4. Radiography - A State-of-the-Art Review

DTIC Science & Technology

1982-06-01

attenuation caused by planar delaminations and voids are indistin- guishable on a radiograph. In this investigation, center-slit specimens were fabri - cated...vendor and as modified by the addition of a gadolinium oxide neutron radiog- raphy image enhancer. A number of specimen assemblies were prepared to...film, types SR-54 and AA were used. A 0.001-inch-thick vapor-deposited gadolinium metal film was used as a converter, see Figure 41 (given as

Synthesis of samarium doped gadolinium oxide nanorods, its spectroscopic and physical properties

NASA Astrophysics Data System (ADS)

Boopathi, G.; Gokul Raj, S.; Ramesh Kumar, G.; Mohan, R.; Mohan, S.

2018-06-01

One-dimensional samarium doped gadolinium oxide [Sm:Gd2O3] nanorods have been synthesized successfully through co-precipitation technique in aqueous solution. The as-synthesized and calcined products were characterized by using powder X-ray diffraction pattern, Fourier transform Raman spectroscopy, thermogravimetric/differential thermal analysis, scanning electron microscopy with energy-dispersive X-ray analysis, transmission electron microscopy, Fourier transform infrared spectroscopy, Ultraviolet-Visible spectrometry, photoluminescence spectrophotometer and X-ray photoelectron spectroscopy techniques. The obtained results are discussed in detailed manner.

Rare-Earth Doping and Co-Doping of GaN for Magnetic and Luminescent Applications

DTIC Science & Technology

2010-08-16

The main focus of this project is the study of Gadolinium doped Gallium Nitride. Calculations were carried out to elucidate the origin of the reported...Ga vacancies in the triple negative charge state, which is the most likely charge state in semi-insulating samples, 1. REPORT DATE (DD-MM-YYYY) 4...applications Report Title ABSTRACT The main focus of this project is the study of Gadolinium doped Gallium Nitride. Calculations were carried out to

Saracatinib in Treating Patients With Metastatic or Locally Advanced Breast Cancer That Cannot Be Removed By Surgery

ClinicalTrials.gov

2014-04-02

Estrogen Receptor-negative Breast Cancer; Male Breast Cancer; Progesterone Receptor-negative Breast Cancer; Recurrent Breast Cancer; Stage IIIB Breast Cancer; Stage IIIC Breast Cancer; Stage IV Breast Cancer

APN401 in Treating Patients With Recurrent or Metastatic Pancreatic Cancer, Colorectal Cancer, or Other Solid Tumors That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-03-29

Metastatic Malignant Neoplasm in the Brain; Metastatic Solid Neoplasm; Recurrent Colorectal Carcinoma; Recurrent Pancreatic Carcinoma; Recurrent Solid Neoplasm; Stage IV Colorectal Cancer; Stage IV Pancreatic Cancer; Stage IVA Colorectal Cancer; Stage IVA Pancreatic Cancer; Stage IVB Colorectal Cancer; Stage IVB Pancreatic Cancer; Unresectable Solid Neoplasm

Pembrolizumab, Capecitabine, and Bevacizumab in Treating Patients With Microsatellite Stable Colorectal Cancer That Is Locally Advanced, Metastatic, or Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-04-04

Microsatellite Stable; Mismatch Repair Protein Proficient; Stage III Colorectal Cancer AJCC v7; Stage IIIB Colorectal Cancer AJCC v7; Stage IIIC Colorectal Cancer AJCC v7; Stage IV Colorectal Cancer AJCC v7; Stage IVA Colorectal Cancer AJCC v7; Stage IVB Colorectal Cancer AJCC v7

Dabrafenib and Trametinib in Treating Patients With Stage III-IV BRAF Mutant Melanoma That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-06-25

BRAF V600E Mutation Present; BRAF V600K Mutation Present; Recurrent Melanoma; Stage III Cutaneous Melanoma AJCC v7; Stage IIIA Cutaneous Melanoma AJCC v7; Stage IIIB Cutaneous Melanoma AJCC v7; Stage IIIC Cutaneous Melanoma AJCC v7; Stage IV Cutaneous Melanoma AJCC v6 and v7

A two-stage approach to removing noise from recorded music

NASA Astrophysics Data System (ADS)

Berger, Jonathan; Goldberg, Maxim J.; Coifman, Ronald C.; Goldberg, Maxim J.; Coifman, Ronald C.

2004-05-01

A two-stage algorithm for removing noise from recorded music signals (first proposed in Berger et al., ICMC, 1995) is described and updated. The first stage selects the ``best'' local trigonometric basis for the signal and models noise as the part having high entropy [see Berger et al., J. Audio Eng. Soc. 42(10), 808-818 (1994)]. In the second stage, the original source and the model of the noise obtained from the first stage are expanded into dyadic trees of smooth local sine bases. The best basis for the source signal is extracted using a relative entropy function (the Kullback-Leibler distance) to compare the sum of the costs of the children nodes to the cost of their parent node; energies of the noise in corresponding nodes of the model noise tree are used as weights. The talk will include audio examples of various stages of the method and proposals for further research.

Catalytic two-stage coal liquefaction process having improved nitrogen removal

DOEpatents

Comolli, Alfred G.

1991-01-01

A process for catalytic multi-stage hydrogenation and liquefaction of coal to produce high yields of low-boiling hydrocarbon liquids containing low concentrations of nitogen compounds. First stage catalytic reaction conditions are 700.degree.-800.degree. F. temperature, 1500-3500 psig hydrogen partial pressure, with the space velocity maintained in a critical range of 10-40 lb coal/hr ft.sup.3 catalyst settled volume. The first stage catalyst has 0.3-1.2 cc/gm total pore volume with at least 25% of the pore volume in pores having diameters of 200-2000 Angstroms. Second stage reaction conditions are 760.degree.-870.degree. F. temperature with space velocity exceeding that in the first stage reactor, so as to achieve increased hydrogenation yield of low-boiling hydrocarbon liquid products having at least 75% removal of nitrogen compounds from the coal-derived liquid products.

CPI-613 and Fluorouracil in Treating Patients With Metastatic Colorectal Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-04-26

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Recurrent Colon Cancer; Recurrent Rectal Cancer; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IIIA Colon Cancer; Stage IIIA Rectal Cancer; Stage IIIB Colon Cancer; Stage IIIB Rectal Cancer; Stage IIIC Colon Cancer; Stage IIIC Rectal Cancer; Stage IVA Colon Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Rectal Cancer

Treatment performances of French constructed wetlands: results from a database collected over the last 30 years.

PubMed

Morvannou, A; Forquet, N; Michel, S; Troesch, S; Molle, P

2015-01-01

Approximately 3,500 constructed wetlands (CWs) provide raw wastewater treatment in France for small communities (<5,000 people equivalent). Built during the past 30 years, most consist of two vertical flow constructed wetlands (VFCWs) in series (stages). Many configurations exist, with systems associated with horizontal flow filters or waste stabilization ponds, vertical flow with recirculation, partially saturated systems, etc. A database analyzed 10 years earlier on the classical French system summarized the global performances data. This paper provides a similar analysis of performance data from 415 full-scale two-stage VFCWs from an improved database expanded by monitoring data available from Irstea and the French technical department. Trends presented in the first study are confirmed, exhibiting high chemical oxygen demand (COD), total suspended solids (TSS) and total Kjeldahl nitrogen (TKN) removal rates (87%, 93% and 84%, respectively). Typical concentrations at the second-stage outlet are 74 mgCOD L(-1), 17 mgTSS L(-1) and 11 mgTKN L(-1). Pollutant removal performances are summarized in relation to the loads applied at the first treatment stage. While COD and TSS removal rates remain stable over the range of applied loads, the spreading of TKN removal rates increases as applied loads increase.

Therapeutic Angiotensin-(1-7) in Treating Patients With Metastatic Sarcoma That Cannot Be Removed By Surgery

ClinicalTrials.gov

2018-02-27

Bone Cancer; Chondrosarcoma; Clear Cell Sarcoma of the Kidney; Metastatic Osteosarcoma; Ovarian Sarcoma; Recurrent Adult Soft Tissue Sarcoma; Recurrent Osteosarcoma; Recurrent Uterine Sarcoma; Stage III Adult Soft Tissue Sarcoma; Stage III Uterine Sarcoma; Stage IV Adult Soft Tissue Sarcoma; Stage IV Uterine Sarcoma

EVALUATION OF A TWO-STAGE PASSIVE TREATMENT APPROACH FOR MINING INFLUENCE WATERS

EPA Science Inventory

A two-stage passive treatment approach was assessed at bench-scale using two Colorado Mining Influenced Waters (MIWs). The first-stage was a limestone drain with the purpose of removing iron and aluminum and mitigating the potential effects of mineral acidity. The second stage w...

Nintedanib Compared With Placebo in Treating Against Radiation-Induced Pneumonitis in Patients With Non-small Cell Lung Cancer That Cannot Be Removed by Surgery and Are Undergoing Chemoradiation Therapy

ClinicalTrials.gov

2017-07-08

Radiation-Induced Pneumonitis; Stage IIA Non-Small Cell Lung Carcinoma; Stage IIB Non-Small Cell Lung Carcinoma; Stage IIIA Non-Small Cell Lung Cancer; Stage IIIB Non-Small Cell Lung Cancer; Stage IV Non-Small Cell Lung Cancer

Independent measurement of the neutrino mixing angle θ 13 via neutron capture on hydrogen at Daya Bay

DOE PAGES

Jaffe, D. E.

2014-10-03

A new measurement of the θ 13 mixing angle has been obtained at the Daya Bay Reactor Neutrino Experiment via the detection of inverse beta decays tagged by neutron capture on hydrogen. The antineutrino events for hydrogen capture are distinct from those for gadolinium capture with largely different systematic uncertainties, allowing a determination independent of the gadolinium-capture result and an improvement on the precision of the θ 13 measurement. With a 217-day antineutrino data set obtained with six antineutrino detectors and from six 2.9 GW th reactors, the rate deficit observed at the far hall is interpreted as sin 22θmore » 13=0.083±0.018 in the three-flavor oscillation model. When combined with the gadolinium-capture result from Daya Bay, we obtain sin 22θ 13=0.089±0.008 as the final result for the six-antineutrino-detector configuration of the Daya Bay experiment.« less

Gadolinium-modulated 19F signals from Perfluorocarbon Nanoparticles as a New Strategy for Molecular Imaging

PubMed Central

Neubauer, Anne M.; Myerson, Jacob; Caruthers, Shelton D.; Hockett, Franklin D.; Winter, Patrick M.; Chen, Junjie; Gaffney, Patrick J.; Robertson, J. David; Lanza, Gregory M.; Wickline, Samuel A.

2008-01-01

Recent advances in the design of fluorinated nanoparticles for magnetic resonance molecular imaging have enabled specific detection of 19F nuclei, providing unique and quantifiable spectral signatures. However, a pressing need for signal enhancement exists because the total 19F in imaging voxels is often limited. By directly incorporating a relaxation agent (gadolinium) into the lipid monolayer that surrounds the perfluorocarbon, a marked augmentation of the 19F signal from 200nm nanoparticles was achieved. This design increases the magnetic relaxation rate of the 19F nuclei 4-fold at 1.5 T and effects a 125% increase in signal, an effect which is maintained when they are targeted to human plasma clots. By varying the surface concentration of gadolinium, the relaxation effect can be quantitatively modulated to tailor particle properties. This novel strategy dramatically improves the sensitivity and range of 19F MRI/MRS and forms the basis for designing contrast agents capable of sensing their surface chemistry. PMID:18956457

Disparate ultrafast dynamics of itinerant and localized magnetic moments in gadolinium metal

PubMed Central

Frietsch, B.; Bowlan, J.; Carley, R.; Teichmann, M.; Wienholdt, S.; Hinzke, D.; Nowak, U.; Carva, K.; Oppeneer, P. M.; Weinelt, M.

2015-01-01

The Heisenberg–Dirac intra-atomic exchange coupling is responsible for the formation of the atomic spin moment and thus the strongest interaction in magnetism. Therefore, it is generally assumed that intra-atomic exchange leads to a quasi-instantaneous aligning process in the magnetic moment dynamics of spins in separate, on-site atomic orbitals. Following ultrashort optical excitation of gadolinium metal, we concurrently record in photoemission the 4f magnetic linear dichroism and 5d exchange splitting. Their dynamics differ by one order of magnitude, with decay constants of 14 versus 0.8 ps, respectively. Spin dynamics simulations based on an orbital-resolved Heisenberg Hamiltonian combined with first-principles calculations explain the particular dynamics of 5d and 4f spin moments well, and corroborate that the 5d exchange splitting traces closely the 5d spin-moment dynamics. Thus gadolinium shows disparate dynamics of the localized 4f and the itinerant 5d spin moments, demonstrating a breakdown of their intra-atomic exchange alignment on a picosecond timescale. PMID:26355196

Hybrid Calcium Phosphate-Polymeric Micelles Incorporating Gadolinium Chelates for Imaging-Guided Gadolinium Neutron Capture Tumor Therapy.

PubMed

Mi, Peng; Dewi, Novriana; Yanagie, Hironobu; Kokuryo, Daisuke; Suzuki, Minoru; Sakurai, Yoshinori; Li, Yanmin; Aoki, Ichio; Ono, Koji; Takahashi, Hiroyuki; Cabral, Horacio; Nishiyama, Nobuhiro; Kataoka, Kazunori

2015-06-23

Gadolinium (Gd) chelates-loaded nanocarriers have high potential for achieving magnetic resonance imaging (MRI)-guided Gd neutron capture therapy (GdNCT) of tumors. Herein, we developed calcium phosphate micelles hybridized with PEG-polyanion block copolymers, and incorporated with the clinical MRI contrast agent Gd-diethylenetriaminepentaacetic acid (Gd-DTPA/CaP). The Gd-DTPA/CaP were nontoxic to cancer cells at the concentration of 100 μM based on Gd-DTPA, while over 50% of the cancer cells were killed by thermal neutron irradiation at this concentration. Moreover, the Gd-DTPA/CaP showed a dramatically increased accumulation of Gd-DTPA in tumors, leading to the selective contrast enhancement of tumor tissues for precise tumor location by MRI. The enhanced tumor-to-blood distribution ratio of Gd-DTPA/CaP resulted in the effective suppression of tumor growth without loss of body weight, indicating the potential of Gd-DTPA/CaP for safe cancer treatment.

The rostral medulla of bullfrog tadpoles contains critical lung rhythmogenic and chemosensitive regions across metamorphosis.

PubMed

Reed, Mitchell D; Iceman, Kimberly E; Harris, Michael B; Taylor, Barbara E

2018-06-08

The development of amphibian breathing provides insight into vertebrate respiratory control mechanisms. Neural oscillators in the rostral and caudal medulla drive ventilation in amphibians, and previous reports describe ventilatory oscillators and CO 2 sensitive regions arise during different stages of amphibian metamorphosis. However, inconsistent findings have been enigmatic, and make comparisons to potential mammalian counterparts challenging. In the current study we assessed amphibian central CO 2 responsiveness and respiratory rhythm generation during two different developmental stages. Whole-nerve recordings of respiratory burst activity in cranial and spinal nerves were made from intact or transected brainstems isolated from tadpoles during early or late stages of metamorphosis. Brainstems were transected at the level of the trigeminal nerve, removing rostral structures including the nucleus isthmi, midbrain, and locus coeruleus, or transected at the level of the glossopharyngeal nerve, removing the putative buccal oscillator and caudal medulla. Removal of caudal structures stimulated the frequency of lung ventilatory bursts and revealed a hypercapnic response in normally unresponsive preparations derived from early stage tadpoles. In preparations derived from late stage tadpoles, removal of rostral or caudal structures reduced lung burst frequency, while CO 2 responsiveness was retained. Our results illustrate that structures within the rostral medulla are capable of sensing CO 2 throughout metamorphic development. Similarly, the region controlling lung ventilation appears to be contained in the rostral medulla throughout metamorphosis. This work offers insight into the consistency of rhythmic respiratory and chemosensitive capacities during metamorphosis. Copyright © 2018. Published by Elsevier Inc.

Entinostat and Anastrozole in Treating Postmenopausal Women With TNBC That Can Be Removed by Surgery

ClinicalTrials.gov

2017-10-02

Estrogen Receptor-negative Breast Cancer; HER2-negative Breast Cancer; Progesterone Receptor-negative Breast Cancer; Stage I Breast Cancer; Stage II Breast Cancer; Stage IIIA Breast Cancer; Triple-negative Breast Cancer

Nivolumab, Cisplatin, and Pemetrexed Disodium or Gemcitabine Hydrochloride in Treating Patients With Stage I-IIIA Non-small Cell Lung Cancer That Can Be Removed by Surgery

ClinicalTrials.gov

2018-03-02

Non-Squamous Non-Small Cell Lung Carcinoma; Stage I Non-Small Cell Lung Cancer; Stage IA Non-Small Cell Lung Carcinoma; Stage IB Non-Small Cell Lung Carcinoma; Stage II Non-Small Cell Lung Cancer; Stage IIA Non-Small Cell Lung Carcinoma; Stage IIB Non-Small Cell Lung Carcinoma; Stage IIIA Non-Small Cell Lung Cancer

Gd-EOB-DTPA-enhanced magnetic resonance imaging and alpha-fetoprotein predict prognosis of early-stage hepatocellular carcinoma.

PubMed

Yamashita, Taro; Kitao, Azusa; Matsui, Osamu; Hayashi, Takehiro; Nio, Kouki; Kondo, Mitsumasa; Ohno, Naoki; Miyati, Tosiaki; Okada, Hikari; Yamashita, Tatsuya; Mizukoshi, Eishiro; Honda, Masao; Nakanuma, Yasuni; Takamura, Hiroyuki; Ohta, Tetsuo; Nakamoto, Yasunari; Yamamoto, Masakazu; Takayama, Tadatoshi; Arii, Shigeki; Wang, XinWei; Kaneko, Shuichi

2014-11-01

The survival of patients with hepatocellular carcinoma (HCC) is often individually different even after surgery for early-stage tumors. Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) has been introduced recently to evaluate hepatic lesions with regard to vascularity and the activity of the organic anion transporter OATP1B3. Here we report that Gd-EOB-DTPA-enhanced MRI (EOB-MRI) in combination with serum alpha-fetoprotein (AFP) status reflects the stem/maturational status of HCC with distinct biology and prognostic information. Gd-EOB-DTPA uptake in the hepatobiliary phase was observed in ∼15% of HCCs. This uptake correlated with low serum AFP levels, maintenance of hepatocyte function with the up-regulation of OATP1B3 and HNF4A expression, and good prognosis. By contrast, HCC showing reduced Gd-EOB-DTPA uptake with high serum AFP levels was associated with poor prognosis and the activation of the oncogene FOXM1. Knockdown of HNF4A in HCC cells showing Gd-EOB-DTPA uptake resulted in the increased expression of AFP and FOXM1 and the loss of OATP1B3 expression accompanied by morphological changes, enhanced tumorigenesis, and loss of Gd-EOB-DTPA uptake in vivo. HCC classification based on EOB-MRI and serum AFP levels predicted overall survival in a single-institution cohort (n=70), and its prognostic utility was validated independently in a multi-institution cohort of early-stage HCCs (n=109). This noninvasive classification system is molecularly based on the stem/maturation status of HCCs and can be incorporated into current staging practices to improve management algorithms, especially in the early stage of disease. © 2014 by the American Association for the Study of Liver Diseases.

Gd-EOB-DTPA-enhanced Magnetic Resonance Imaging and Alpha-fetoprotein Predict Prognosis of Early-Stage Hepatocellular Carcinoma

PubMed Central

Yamashita, Taro; Kitao, Azusa; Matsui, Osamu; Hayashi, Takehiro; Nio, Kouki; Kondo, Mitsumasa; Ohno, Naoki; Miyati, Tosiaki; Okada, Hikari; Yamashita, Tatsuya; Mizukoshi, Eishiro; Honda, Masao; Nakanuma, Yasuni; Takamura, Hiroyuki; Ohta, Tetsuo; Nakamoto, Yasunari; Yamamoto, Masakazu; Takayama, Tadatoshi; Arii, Shigeki; Wang, Xin Wei; Kaneko, Shuichi

2014-01-01

The survival of patients with hepatocellular carcinoma (HCC) is often individually different even after surgery for early-stage tumors. Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) has been introduced recently to evaluate hepatic lesions with regard to vascularity and the activity of the organic anion transporter OATP1B3. Here, we report that Gd-EOB-DTPA-enhanced MRI (EOB-MRI) in combination with serum alpha-fetoprotein (AFP) status reflects the stem/maturational status of HCC with distinct biology and prognostic information. Gd-EOB-DTPA uptake in the hepatobiliary phase was observed in approximately 15% of HCCs. This uptake correlated with low serum AFP levels, maintenance of hepatocyte function with the up-regulation of OATP1B3 and HNF4A expression, and good prognosis. By contrast, HCC showing reduced Gd-EOB-DTPA uptake with high serum AFP levels was associated with poor prognosis and the activation of the oncogene FOXM1. Knockdown of HNF4A in HCC cells showing Gd-EOB-DTPA uptake resulted in the increased expression of AFP and FOXM1 and the loss of OATP1B3 expression accompanied by morphological changes, enhanced tumorigenesis, and loss of Gd-EOB-DTPA uptake in vivo. HCC classification based on EOB-MRI and serum AFP levels predicted overall survival in a single-institution cohort (n = 70), and its prognostic utility was validated independently in a multi-institution cohort of early-stage HCCs (n = 109). Conclusion: This non-invasive classification system is molecularly based on the stem/maturation status of HCCs and can be incorporated into current staging practices to improve management algorithms, especially in the early stage of disease. PMID:24700365

Enhanced P, N and C removal from domestic wastewater using constructed wetland employing construction solid waste (CSW) as main substrate.

PubMed

Yang, Y; Wang, Z M; Liu, C; Guo, X C

2012-01-01

Construction solid waste (CSW), an inescapable by-product of the construction and demolition process, was used as main substrate in a four-stage vertical subsurface flow constructed wetland system to improve phosphorus P removal from domestic wastewater. A 'tidal flow' operation was also employed in the treatment system. Under a hydraulic loading rate (HLR) of 0.76 m3/m2 d for 1st and 3rd stage and HLR of 0.04 m3/m2 d for 2nd and 4th stage of the constructed wetland system respectively and tidal flow operation strategy, average removal efficiencies of 99.4% for P, 95.4% for ammoniacal-nitrogen, 56.5% for total nitrogen and 84.5% for total chemical oxygen demand were achieved during the operation period. The CSW-based constructed wetland system presents excellent P removal performance. The adoption of tidal flow strategy creates the aerobic/anoxic condition intermittently in the treatment system. This can achieve better oxygen transfer and hence lead to more complete nitrification and organic matter removal and enhanced denitrification. Overall, the CSW-based tidal flow constructed wetland system holds great promise for enabling high rate removal of P, ammoniacal-nitrogen and organic matter from domestic wastewater, and transforms CSW from a waste into a useful material.

[Relationship between the nitrogen removal and oxygen demand in constructed wetlands].

PubMed

He, Lian-sheng; Liu, Hong-liang; Xi, Bei-dou; Zhu, Ying-bo; Wei, Zi-min; Huo, Shou-liang

2006-06-01

A simplified model of sequential N transformations and sink was applied to investigate the relationship between the nitrogen removal and oxygen demand to verify the validity of full nitrification-denitrification mechanism in a newly-built multi-stages constructed wetlands. Average net rates of N mineralization ranged from 0.01 to 0.28 g x (m2 x d)(-1), nitrification from 0.50 to 1.54 g x (m2 x d)(-1), denitrification from 0.41 to 1.13 g x (m2 x d)(-1)(3.4% approximately 35.4% of measured N removal in different stage) and plant assimilation from 0.07 to 0.26 g x (m2 x d)(-1) in the five tanks. Nitrification and denitrification occurred concurrently with BOD removal, even in the first stage receiving the higher-strength wastewater. Surprisingly, net areal nitrification rates, was correlated with BOD removal rates positively. Nitrification rates were also correlated linearly with average NH4+-N concentrations in the cascade tanks. The nitrogenous oxygen demand (NOD) required to support full nitrification of ammonia and mineralized Org-N in the wetland was in the upper range of that expected to be able to be supplied through surface and plant-mediated oxygen transfer. Some potential alternative nitrogen removal pathways with reduced overall oxygen requirements that have relevance to constructed wetlands were discussed.

Improved removal performance and mechanism investigation of papermaking wastewater treatment using manganese enhanced Fenton reaction.

PubMed

Wang, Yingcai; Wang, Can; Shi, Shuai; Fang, Shuai

2018-06-01

The effects of Mn(II) on Fenton system to treat papermaking wastewater and the mechanism of Mn(II) enhanced Fenton reaction were investigated in this study. The chemical oxygen demand (COD) removal efficiency was enhanced in the presence of Mn(II), which increased by 19% compared with that of the Fenton system alone. The pseudo-first order reaction kinetic rate constant of Mn(II)/Fenton system was 2.11 times higher than that of Fenton system. 67%-81% COD were removed with the increasing Mn(II) concentration from 0 to 0.8 g/L. COD removal efficiency was also enhanced in a wider pH range (3-7), which indicated the operation parameters of Fenton technology could be broadened to a milder condition. The study of the mechanism showed that Mn(II) participated in the oxidation and coagulation stages in Fenton system. In the oxidation stage, Mn(II) promotes the production of HO 2 •/ O 2 • - , then HO 2 •/ O 2 • - reacts with Fe(III) to accelerate the formation of Fe(II), and finally accelerates the production of HO•. Meantime MnMnO 3 and Fe(OH) 3 forms in the coagulation stage, facilitating the removal of suspended substances and a large amount of COD, which enhances the overall COD removal of papermaking wastewater. This study provided a detailed mechanism to improve practical applications of Fenton technology.

Rare case of Cushing's disease due to double ACTH-producing adenomas, one located in the pituitary gland and one into the stalk.

PubMed

Mendola, Marco; Dolci, Alessia; Piscopello, Lanfranco; Tomei, Giustino; Bauer, Dario; Corbetta, Sabrina; Ambrosi, Bruno

2014-01-01

We describe a patient affected by Cushing's disease due to the presence of double pituitary adenomas, one located within the anterior pituitary and the other in the infundibulum associated with a remnant of Rakthe's pouch. Cure was achieved only after the infundibulum lesion was surgically removed. A 38-year-old female presented with unexplained weight gain, hirsutism, amenorrhea, asthenia, recurrent cutaneous micotic infections and alopecia. Hormonal studies indicated Cushing's disease and MRI showed an enlarged pituitary gland with a marked and homogeneous enhancement after injection of gadolinium and an enlarged infundibulum with a maximum diameter of 8 mm. As a venous sampling of the inferior petrosal sinus after 10 μg iv desmopressin stimulation revealed a central to peripheral ACTH ratio consistent with a pituitary ACTH-secreting tumor, transphenoidal explorative surgery was performed and a 4-mm pituitary adenoma immunopositive for ACTH was disclosed and removed. Since postoperative hormonal evaluation showed persistent hypercortisolism, confirmed by dynamic tests, the patient again underwent surgery by transcranial access and the infundibulum mass was removed. Histology and immunochemistry were consistent with an ACTH-secreting adenoma. A few months after the second operation, cushingoid features were significantly reverted and symptoms improved. Although Cushing's patients bearing multiple adenomas have already been documented, the presence of two adenomas both immunohistochemically positive for ACTH is a very rare cause of Cushing's disease and this is the first report of a case of double ACTH-producing adenomas, one located in the pituitary gland and one attached to the stalk.

Gadolinium-based nanoparticles to improve the hadrontherapy performances.

PubMed

Porcel, Erika; Tillement, Olivier; Lux, François; Mowat, Pierre; Usami, Noriko; Kobayashi, Katsumi; Furusawa, Yoshiya; Le Sech, Claude; Li, Sha; Lacombe, Sandrine

2014-11-01

Nanomedicine is proposed as a novel strategy to improve the performance of radiotherapy. High-Z nanoparticles are known to enhance the effects of ionizing radiation. Recently, multimodal nanoparticles such as gadolinium-based nanoagents were proposed to amplify the effects of x-rays and g-rays and to improve MRI diagnosis. For tumors sited in sensitive tissues, childhood cases and radioresistant cancers, hadrontherapy is considered superior to x-rays and g-rays. Hadrontherapy, based on fast ion radiation, has the advantage of avoiding damage to the tissues behind the tumor; however, the damage caused in front of the tumor is its major limitation. Here, we demonstrate that multimodal gadolinium-based nanoparticles amplify cell death with fast ions used as radiation. Molecular scale experiments give insights into the mechanisms underlying the amplification of radiation effects. This proof-of-concept opens up novel perspectives for multimodal nanomedicine in hadrontherapy, ultimately reducing negative radiation effects in healthy tissues in front of the tumor. Gadolinium-chelating polysiloxane nanoparticles were previously reported to amplify the anti-tumor effects of x-rays and g-rays and to serve as MRI contrast agents. Fast ion radiation-based hadrontherapy avoids damage to the tissues behind the tumor, with a major limitation of tissue damage in front of the tumor. This study demonstrates a potential role for the above nanoagents in optimizing hadrontherapy with preventive effects in healthy tissue and amplified cell death in the tumor. Copyright © 2014 Elsevier Inc. All rights reserved.

A first principles kinetic Monte Carlo investigation of the adsorption and mobility of gadolinium on the (100) surface of tungsten

NASA Astrophysics Data System (ADS)

Samin, Adib J.; Zhang, Jinsuo

2017-05-01

An accurate characterization of lanthanide adsorption and mobility on tungsten surfaces is important for pyroprocessing. In the present study, the adsorption and diffusion of gadolinium on the (100) surface of tungsten was investigated. It was found that the hollow sites were the most energetically favorable for the adsorption. It was further observed that a magnetic moment was induced following the adsorption of gadolinium on the tungsten surface and that the system with adsorbed hollow sites had the largest magnetization. A pathway for the surface diffusion of gadolinium was determined to occur by hopping between the nearest neighbor hollow sites via the bridge site and the activation energy for the hop was calculated to be 0.75 eV. The surface diffusion process was further assessed using two distinct kinetic Monte Carlo models; one that accounted for lateral adsorbate interactions up to the second nearest neighbor and one that did not account for such interatomic interactions in the adlayer. When the lateral interactions were included in the simulations, the diffusivity was observed to have a strong dependence on coverage (for the coverage values being studied). The effects of lateral interactions were further observed in a one-dimensional simulation of the diffusion equation where the asymmetry in the surface coverage profile upon its approach to a steady state distribution was clear in comparison with the simulations which did not account for those interactions.

Evaluation of Novel 64Cu-Labeled Theranostic Gadolinium-Based Nanoprobes in HepG2 Tumor-Bearing Nude Mice.

PubMed

Hu, Pengcheng; Cheng, Dengfeng; Huang, Tao; Banizs, Anna B; Xiao, Jie; Liu, Guobing; Chen, Quan; Wang, Yuenan; He, Jiang; Shi, Hongcheng

2017-09-06

Radiation therapy of liver cancer is limited by low tolerance of the liver to radiation. Radiosensitizers can effectively reduce the required radiation dose. AGuIX nanoparticles are small, multifunctional gadolinium-based nanoparticles that can carry radioisotopes or fluorescent markers for single-photon emission computed tomography (SPECT), positron emission tomography (PET), fluorescence imaging, and even multimodality imaging. In addition, due to the high atomic number of gadolinium, it can also serve as a tumor radiation sensitizer. It is critical to define the biodistribution and pharmacokinetics of these gadolinium-based nanoparticles to quantitate the magnitude and duration of their retention within the tumor microenvironment during radiotherapy. Therefore, in this study, we successfully labeled AGuIX with 64 Cu through the convenient built-in chelator. The biodistribution studies indicated that the radiotracer 64 Cu-AGuIX accumulates to high levels in the HepG2 xenograft of nude mice, suggesting that it would be a potential theranostic nanoprobe for image-guided radiotherapy in HCC. We also used a transmission electron microscope to confirm AGuIX uptake in the HepG2 cells. In radiation therapy studies, a decrease in 18 F-FDG uptake was observed in the xenografts of the nude mice irradiated with AGuIX, which was injected 1 h before. These results provide proof-of-concept that AGuIX can be used as a theranostic radiosensitizer for PET imaging to guide radiotherapy for liver cancer.

High-pressure high-temperature phase diagram of gadolinium studied using a boron-doped heater anvil

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

Montgomery, J. M.; Samudrala, G. K.; Velisavljevic, N.

A boron-doped designer heater anvil is used in conjunction with powder x-ray diffraction to collect structural information on a sample of quasi-hydrostatically loaded gadolinium metal up to pressures above 8 GPa and 600 K. The heater anvil consists of a natural diamond anvil that has been surface modified with a homoepitaxially-grown chemical-vapor-deposited layer of conducting boron-doped diamond, and is used as a DC heating element. Internally insulating both diamond anvils with sapphire support seats allows for heating and cooling of the high pressure area on the order of a few tens of seconds. This device is then used to scanmore » the phase diagram of the sample by oscillating the temperature while continuously increasing the externally applied pressure and collecting in situ time-resolved powder diffraction images. In the pressure-temperature range covered in the experiment the gadolinium sample is observed in its hcp, αSm, and dhcp phases. Under this temperature cycling, the hcp→αSm transition proceeds in discontinuous steps at points along the expected phase boundary. Additionally, the unit cell volumes of each phase deviate from the expected thermal expansion behavior just before each transition is observed from the diffraction data. From these measurements (representing only one hour of synchrotron x-ray collection time), a single-experiment equation of state and phase diagram of each phase of gadolinium is presented for the range of 0 - 10 GPa and 300 - 650 K.« less

Quantitative assessment of the rheumatoid synovial microvascular bed by gadolinium-DTPA enhanced magnetic resonance imaging

PubMed Central

Gaffney, K.; Cookson, J.; Blades, S.; Coumbe, A.; Blake, D.

1998-01-01

OBJECTIVE—To examine the relation between rate of synovial membrane enhancement, intra-articular pressure (IAP), and histologically determined synovial vascularity in rheumatoid arthritis, using gadolinium-DTPA enhanced magnetic resonance imaging (MRI).
METHODS—Dynamic gadolinium-DTPA enhanced MRI was performed in 31 patients with knee synovitis (10 patients IAP study, 21 patients vascular morphometry study). Rate of synovial membrane enhancement was quantified by line profile analysis using the image processing package ANALYZE. IAP was measured using an intra-compartmental pressure monitor system. Multiple synovial biopsy specimens were obtained by a blind biopsy technique. Blood vessels were identified immunohistochemically using the endothelial cell marker QBend30 and quantified (blood vessel numerical density and fractional area).
RESULTS—Median blood vessel numerical density and fractional area were 77.5/mm2 (IQR; 69.3-110.7) and 5.6% (IQR; 3.4-8.5) respectively. The rate of synovial membrane enhancement (median 2.74 signal intensity units/s, IQR 2.0-3.8) correlated with both blood vessel numerical density (r = 0.46, p < 0.05) and blood vessel fractional area (r = 0.55, p < 0.02). IAP did not influence the rate of enhancement.
CONCLUSIONS—Gadolinium-DTPA enhanced MRI may prove to be a valuable technique for evaluating drugs that influence angiogenesis.

 Keywords: magnetic resonance imaging; rheumatoid arthritis; synovitis; vascularity PMID:9640130

Breakthrough reactions of iodinated and gadolinium contrast media after oral steroid premedication protocol.

PubMed

Jingu, Akiko; Fukuda, Junya; Taketomi-Takahashi, Ayako; Tsushima, Yoshito

2014-10-06

Adverse reactions to iodinated and gadolinium contrast media are an important clinical issue. Although some guidelines have proposed oral steroid premedication protocols to prevent adverse reactions, some patients may have reactions to contrast media in spite of premedication (breakthrough reaction; BTR).The purpose of this study was to assess the frequency, type and severity of BTR when following an oral steroid premedication protocol. All iodinated and gadolinium contrast-enhanced radiologic examinations between August 2011 and February 2013 for which the premedication protocol was applied in our institution were assessed for BTRs. The protocol was applied to a total of 252 examinations (153 patients, ages 15-87 years; 63 males, 90 females). Of these, 152 were for prior acute adverse reactions to contrast media, 85 were for a history of bronchial asthma, and 15 were for other reasons. There were 198 contrast enhanced CTs and 54 contrast enhanced MRIs. There were nine BTR (4.5%) for iodinated contrast media, and only one BTR (1.9%) for gadolinium contrast media: eight were mild and one was moderate. No patient who had a mild index reaction (IR) had a severe BTR. Incidence of BTRs when following the premedication protocol was low. This study by no means proves the efficacy of premedication, but provides some support for following a premedication protocol to improve safety of contrast-enhanced examinations when prior adverse reactions are mild, or when there is a history of asthma.

Breakthrough reactions of iodinated and gadolinium contrast media after oral steroid premedication protocol

PubMed Central

2014-01-01

Background Adverse reactions to iodinated and gadolinium contrast media are an important clinical issue. Although some guidelines have proposed oral steroid premedication protocols to prevent adverse reactions, some patients may have reactions to contrast media in spite of premedication (breakthrough reaction; BTR). The purpose of this study was to assess the frequency, type and severity of BTR when following an oral steroid premedication protocol. Methods All iodinated and gadolinium contrast-enhanced radiologic examinations between August 2011 and February 2013 for which the premedication protocol was applied in our institution were assessed for BTRs. Results The protocol was applied to a total of 252 examinations (153 patients, ages 15–87 years; 63 males, 90 females). Of these, 152 were for prior acute adverse reactions to contrast media, 85 were for a history of bronchial asthma, and 15 were for other reasons. There were 198 contrast enhanced CTs and 54 contrast enhanced MRIs. There were nine BTR (4.5%) for iodinated contrast media, and only one BTR (1.9%) for gadolinium contrast media: eight were mild and one was moderate. No patient who had a mild index reaction (IR) had a severe BTR. Conclusion Incidence of BTRs when following the premedication protocol was low. This study by no means proves the efficacy of premedication, but provides some support for following a premedication protocol to improve safety of contrast-enhanced examinations when prior adverse reactions are mild, or when there is a history of asthma. PMID:25287952

Evaluation of Novel 64Cu-Labeled Theranostic Gadolinium-Based Nanoprobes in HepG2 Tumor-Bearing Nude Mice

NASA Astrophysics Data System (ADS)

Hu, Pengcheng; Cheng, Dengfeng; Huang, Tao; Banizs, Anna B.; Xiao, Jie; Liu, Guobing; Chen, Quan; Wang, Yuenan; He, Jiang; Shi, Hongcheng

2017-09-01

Radiation therapy of liver cancer is limited by low tolerance of the liver to radiation. Radiosensitizers can effectively reduce the required radiation dose. AGuIX nanoparticles are small, multifunctional gadolinium-based nanoparticles that can carry radioisotopes or fluorescent markers for single-photon emission computed tomography (SPECT), positron emission tomography (PET), fluorescence imaging, and even multimodality imaging. In addition, due to the high atomic number of gadolinium, it can also serve as a tumor radiation sensitizer. It is critical to define the biodistribution and pharmacokinetics of these gadolinium-based nanoparticles to quantitate the magnitude and duration of their retention within the tumor microenvironment during radiotherapy. Therefore, in this study, we successfully labeled AGuIX with 64Cu through the convenient built-in chelator. The biodistribution studies indicated that the radiotracer 64Cu-AGuIX accumulates to high levels in the HepG2 xenograft of nude mice, suggesting that it would be a potential theranostic nanoprobe for image-guided radiotherapy in HCC. We also used a transmission electron microscope to confirm AGuIX uptake in the HepG2 cells. In radiation therapy studies, a decrease in 18F-FDG uptake was observed in the xenografts of the nude mice irradiated with AGuIX, which was injected 1 h before. These results provide proof-of-concept that AGuIX can be used as a theranostic radiosensitizer for PET imaging to guide radiotherapy for liver cancer.

High-pressure high-temperature phase diagram of gadolinium studied using a boron-doped heater anvil

DOE PAGES

Montgomery, J. M.; Samudrala, G. K.; Velisavljevic, N.; ...

2016-04-07

A boron-doped designer heater anvil is used in conjunction with powder x-ray diffraction to collect structural information on a sample of quasi-hydrostatically loaded gadolinium metal up to pressures above 8 GPa and 600 K. The heater anvil consists of a natural diamond anvil that has been surface modified with a homoepitaxially-grown chemical-vapor-deposited layer of conducting boron-doped diamond, and is used as a DC heating element. Internally insulating both diamond anvils with sapphire support seats allows for heating and cooling of the high pressure area on the order of a few tens of seconds. This device is then used to scanmore » the phase diagram of the sample by oscillating the temperature while continuously increasing the externally applied pressure and collecting in situ time-resolved powder diffraction images. In the pressure-temperature range covered in the experiment the gadolinium sample is observed in its hcp, αSm, and dhcp phases. Under this temperature cycling, the hcp→αSm transition proceeds in discontinuous steps at points along the expected phase boundary. Additionally, the unit cell volumes of each phase deviate from the expected thermal expansion behavior just before each transition is observed from the diffraction data. From these measurements (representing only one hour of synchrotron x-ray collection time), a single-experiment equation of state and phase diagram of each phase of gadolinium is presented for the range of 0 - 10 GPa and 300 - 650 K.« less

Relaxivity enhancement of aquated Tris(β-diketonate)gadolinium(III) chelates by confinement within ultrashort single-walled carbon nanotubes.

PubMed

Law, Justin J; Guven, Adem; Wilson, Lon J

2014-01-01

Ultrashort single-walled carbon nanotubes loaded with gadolinium ions (gadonanotubes) have been previously shown to exhibit extremely high T1 -weighted relaxivities (>100 mm(-1) s(-1) ). To further examine the effect of nanoconfinement on the relaxivity of gadolinium-based contrast agents for magnetic resonance imaging, a series of ultrashort single-walled carbon nanotube (US-tube) materials internally loaded with gadolinium chelates have been prepared and studied. US-tubes were loaded with Gd(acac)3  · 2H2 O, Gd(hfac)3  · 2H2 O, and Gd(thd)3 (acac = acetylacetone, hfac = hexafluoroacetylacetone, thd = tetramethylheptanedione). The longitudinal relaxivities of the prepared materials determined at 25°C in a 1.5 T field were 103 mm(-1) s(-1) for Gd(acac)3  · 2H2 O@US-tubes, 105 mm(-1) s(-1) for Gd(hfac)3  · 2H2 O@US-tubes and 26 mm(-1) s(-1) for Gd(thd)3 @US-tubes. Compared with the relaxivities obtained for the unloaded chelates (<10 mm(-1) s(-1) ) as well as accounting for the T1 reduction observed for the empty US-tubes, the boost in relaxivity for chelate-loaded US-tubes is attributed to confinement within the nanotube and depends on the number of coordinated water molecules. Copyright © 2014 John Wiley & Sons, Ltd.

Pembrolizumab, Combination Chemotherapy, and Radiation Therapy Before Surgery in Treating Adult Patients With Locally Advanced Gastroesophageal Junction or Gastric Cardia Cancer That Can Be Removed by Surgery

ClinicalTrials.gov

2018-04-13

Gastric Cardia Adenocarcinoma; Gastroesophageal Junction Adenocarcinoma; Stage IB Gastric Cancer AJCC v7; Stage II Gastric Cancer AJCC v7; Stage IIA Gastric Cancer AJCC v7; Stage IIB Gastric Cancer AJCC v7; Stage IIIA Gastric Cancer AJCC v7; Stage IIIB Gastric Cancer AJCC v7

Soil infiltration bioreactor incorporated with pyrite-based (mixotrophic) denitrification for domestic wastewater treatment.

PubMed

Kong, Zhe; Li, Lu; Feng, Chuanping; Chen, Nan; Dong, Shanshan; Hu, Weiwu

2015-01-01

In this study, an integrated two-stage soil infiltration bioreactor incorporated with pyrite-based (mixotrophic) denitrification (SIBPD) was designed for domestic wastewater treatment. Benefited from excellent adsorption ability and water-permeability, soil infiltration could avoid clogging, shorten operating time and lower maintenance cost. Respiration and nitrification were mostly engaged in aerobic stage (AES), while nitrate was majorly removed by pyrite-based mixotrophic denitrification mainly occurred in anaerobic stage (ANS). Fed with synthetic and real wastewater for 120days at 1.5h HRT, SIBPD demonstrated good removal performance showing 87.14% for COD, 92.84% for NH4(+)-N and 82.58% for TP along with 80.72% of nitrate removed by ANS. TN removal efficiency was 83.74% when conducting real wastewater. Compared with sulfur-based process, the effluent pH of SIBPD was maintained at 6.99-7.34 and the highest SO4(2-) concentration was only 64.63mgL(-1). This study revealed a promising and feasible application prospect for on-site domestic wastewater treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Transition from a failing dentition to a removable implant-supported prosthesis: a staged approach.

PubMed

Cordaro, Luca; Torsello, Ferruccio; Ribeiro, Carlos Accorsi

2010-05-01

Patients with hopeless dentition often present difficulties in the management of the transitional phase to the final restoration. This article describes a staged approach to achieve a full-arch, implant-supported, removable prosthesis in patients with a hopeless dentition. The approach described allows the clinician to proceed in a staged manner and facilitate prosthetic steps by keeping fixed references for vertical dimension. This technique includes initial conservative periodontal care and, afterward, extraction of some strategic teeth, while others are temporarily maintained. At this point, the implants are positioned, and during the healing period, the remaining natural abutments are used for occlusal reference and to stabilize the removable provisional prosthesis. After osseointegration of the implants, the residual teeth are extracted and the final prosthesis is delivered. The main advantages of the technique include maintenance of function during treatment, stabilization of the removable provisional (especially in the mandibular arch), prosthetic-guided insertion of implants, and easier retrieval of prosthetic references. The main drawbacks are longer treatment time and the need for two surgical steps.

Evaluation of liver function using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid enhanced magnetic resonance imaging based on a three-dimensional volumetric analysis system.

PubMed

Kudo, Masashi; Gotohda, Naoto; Sugimoto, Motokazu; Kobayashi, Tatsushi; Kojima, Motohiro; Takahashi, Shinichiro; Konishi, Masaru; Hayashi, Ryuichi

2018-06-02

Magnetic resonance imaging with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (EOB-MRI) is a diagnostic modality for liver tumors. Three-dimensional (3D) volumetric analysis systems using EOB-MRI data are used to simulate liver anatomy for surgery. This study was conducted to investigate clinical utility of a 3D volumetric analysis system on EOB-MRI to evaluate liver function. Between August 2014 and December 2015, 181 patients underwent laboratory and radiological exams as standardized preoperative evaluation for liver surgery. The liver-spleen contrast-enhanced ratio (LSR) was measured by a semi-automated 3D volumetric analysis system on EOB-MRI. First, the inter-evaluator variability of the calculated LSR was evaluated. Additionally, a subset of liver surgical specimens was evaluated histologically by using immunohistochemical staining. Finally, the correlations between the LSR and grading systems of liver function, laboratory data, or histological findings were analyzed. The inter-evaluator correlation coefficient of the measured LSR was 0.986. The mean LSR was significantly correlated with the Child-Pugh score (p = 0.014) and the ALBI score (p < 0.001). Significant correlations were also observed between the LSR and indocyanine green retention rate at 15 min (r = - 0.601, p < 0.001), between the LSR and liver fibrosis stage (r = - 0.556, p < 0.001), and between the LSR and liver steatosis grade (r = - 0.396, p < 0.001). The LSR calculated by a 3D volumetric analysis system on EOB-MRI was highly reproducible and was shown to be correlated with liver function parameters and liver histology. These data suggest that this imaging modality can be a reliable tool to evaluate liver function.

Presence of non-hypervascular hypointense nodules on Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging in patients with hepatocellular carcinoma.

PubMed

Inoue, Masanori; Ogasawara, Sadahisa; Chiba, Tetsuhiro; Ooka, Yoshihiko; Wakamatsu, Toru; Kobayashi, Kazufumi; Suzuki, Eiichiro; Tawada, Akinobu; Yokosuka, Osamu

2017-04-01

Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) performed before curative therapy for hepatocellular carcinoma (HCC) can distinguish between intrahepatic distant recurrence and hypervascularization. This study aimed to retrospectively evaluate the presence of non-hypervascular hypointense nodules on hepatobiliary phase images from Gd-EOB-DTPA-enhanced MRI as a risk factor of the intrahepatic distant recurrence of early stage HCC following radiofrequency ablation (RFA). A total of 132 patients who underwent preprocedural Gd-EOB-DTPA-enhanced MRI followed by initial RFA were retrospectively analyzed. Post-RFA intrahepatic distant recurrence, which excluded the hypervascularization of non-hypervascular hypointense nodules detected by preprocedural Gd-EOB-DTPA-enhanced MRI, was evaluated according to the presence of non-hypervascular hypointense nodules on preprocedural Gd-EOB-DTPA-enhanced MRI. Intrahepatic distant recurrence rates following RFA were higher in patients with non-hypervascular hypointense nodules (1-year: 22.5%, 2-year: 52.1%, 5-year: 89.1%) compared with in patients without non-hypervascular hypointense nodules (1-year: 7.0%, 2-year: 28.8%, 5-year: 48.7%). The presence of non-hypervascular hypointense nodules was associated with markedly increased cumulative recurrence rates of both identical and different subsegment intrahepatic distant recurrence, being an independent risk factor for post-RFA identical and different subsegment intrahepatic distant recurrence (identical: HR = 2.365, P = 0.027; different: HR = 3.276, P < 0.001). The presence of non-hypervascular hypointense nodules on hepatobiliary phase images from Gd-EOB-DTPA-enhanced MRI obtained prior to RFA is an important predictive factor of intrahepatic distant recurrence following RFA of HCC. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Measurement of glomerular filtration rate using dynamic magnetic resonance imaging in patients with chronic kidney disease.

PubMed

Artunc, Ferruh; Yildiz, Serdar; Boss, Andreas; Frenzel, Thomas; Schlemmer, Heinz-Peter; Schick, Fritz; Risler, Teut; Häring, Hans-Ulrich; Rossi, Cristina

2011-01-01

Determination of glomerular filtration rate (GFR) using plasma disappearance curves requires the injection of a filtration marker and repeated timed blood collections. Gadolinium-containing contrast media are excreted exclusively by glomerular filtration and could provide a novel approach to quantifying GFR using magnetic resonance (MR) imaging. The aim of this study was to demonstrate the feasibility of measuring GFR by the clearance of gadolinium-containing contrast medium in patients with chronic kidney disease (CKD). Informed consent was obtained from stable CKD patients in stages 1, 2 or 3 (n=16; 5 women, 11 men; median age 54 years). GFR was measured after a bolus injection of gadobutrol (4 mL, approximately 0.05 mmol/kg) and calculated from the washout of the signal intensity obtained over the liver. The obtained MR-GFR was compared with simultaneously measured plasma clearance of inulin and gadobutrol. Technical failure occurred in 2 patients. The mean obtained MR-GFR was 71 ± 25 (SD) mL/min per 1.73 m² and agreed well with the mean inulin-GFR (70 ± 24 mL/min per 1.73 m²). Pearson's correlation coefficient was r=0.91. The mean of the paired differences was 1 ± 10 mL/min per 1.73 m² and not significantly different from zero. GFR obtained from gadobutrol plasma clearance also agreed well with inulin-GFR and MR-GFR (r=0.92 and r=0.75, respectively). We describe a novel method of determining GFR from MR imaging using a low dose of gadobutrol in patients with reduced GFR that enables the absolute quantification of GFR after routine contrast-enhanced MR imaging.

Landfill Leachate Treatment by Electrocoagulation and Fiber Filtration.

PubMed

Li, Runwei; Wang, Boya; Owete, Owete; Dertien, Joe; Lin, Chen; Ahmad, Hafiz; Chen, Gang

2017-11-01

  Landfilling is widely adopted as one of the most economical processes for solid waste disposal. At the same time, landfill leachate is also a great environmental concern owing to its complex composition and high concentrations of contaminants. This research investigated electrocoagulation and fiber filtration for the treatment of landfill leachate. Besides electrical current (i.e., current density) and reaction time, pH played a very important role in arsenic and phosphorus removal by electrocoagulation. The combination of electrocoagulation with fiber filtration achieved a 94% chemical oxygen demand (COD), 87% arsenic, 96% iron, and 86% phosphorus removal. During electrocoagulation, the micro-particles that could not be settled by gravity were removed by the first stage of fiber filtration. Organic contaminants in the leachate were further removed by biodegradation in the second stage of fiber biofiltration.

Sequential anaerobic/aerobic digestion for enhanced sludge stabilization: comparison of the process performance for mixed and waste sludge [corrected].

PubMed

Tomei, M Concetta; Carozza, Nicola Antonello

2015-05-01

Sequential anaerobic-aerobic digestion has been demonstrated as a promising alternative for enhanced sludge stabilization. In this paper, a feasibility study of the sequential digestion applied to real waste activated sludge (WAS) and mixed sludge is presented. Process performance is evaluated in terms of total solid (TS) and volatile solid (VS) removal, biogas production, and dewaterability trend in the anaerobic and double-stage digested sludge. In the proposed digestion lay out, the aerobic stage was operated with intermittent aeration to reduce the nitrogen load recycled to the wastewater treatment plant (WWTP). Experimental results showed a very good performance of the sequential digestion process for both waste and mixed sludge, even if, given its better digestibility, higher efficiencies are observed for mixed sludge. VS removal efficiencies in the anaerobic stage were 48 and 50% for waste and mixed sludge, respectively, while a significant additional improvement of the VS removal of 25% for WAS and 45% for mixed sludge has been obtained in the aerobic stage. The post-aerobic stage, operated with intermittent aeration, was also efficient in nitrogen removal, providing a significant decrease of the nitrogen content in the supernatant: nitrification efficiencies of 90 and 97% and denitrification efficiencies of 62 and 70% have been obtained for secondary and mixed sludges, respectively. A positive effect due to the aerobic stage was also observed on the sludge dewaterability in both cases. Biogas production, expressed as Nm(3)/(kgVSdestroyed), was 0.54 for waste and 0.82 for mixed sludge and is in the range of values reported in the literature in spite of the low anaerobic sludge retention time of 15 days.

Biological Pilot Plant Study at Radford Army Ammunition Plant

DTIC Science & Technology

1976-10-01

amount of organics applied to the rotating bio- logical disc system was substantially incre sed when the hy- draulic loading was increased from 2 GPD/ft... organic loading, therefore, the effluent organic con- centrations increased significantly. The increase in effluent BOD and COD after May 13th are...provided some additional organic removal while the third and fourth stages began providing an increased amount of organic removal. The first stage soluble

Gefitinib in Treating Patients With Stage IB, II, or IIIA Non-small Cell Lung Cancer That Was Completely Removed by Surgery

ClinicalTrials.gov

2014-12-19

Adenocarcinoma of the Lung; Adenosquamous Cell Lung Cancer; Bronchoalveolar Cell Lung Cancer; Large Cell Lung Cancer; Squamous Cell Lung Cancer; Stage IB Non-small Cell Lung Cancer; Stage IIA Non-small Cell Lung Cancer; Stage IIB Non-small Cell Lung Cancer; Stage IIIA Non-small Cell Lung Cancer

Trametinib, Combination Chemotherapy, and Radiation Therapy in Treating Patients With Stage III Non-small Cell Lung Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-05-23

KRAS Activating Mutation; Recurrent Non-Small Cell Lung Carcinoma; Stage III Non-Small Cell Lung Cancer AJCC v7; Stage IIIA Non-Small Cell Lung Cancer AJCC v7; Stage IIIB Non-Small Cell Lung Cancer AJCC v7

Combination Chemotherapy and Filgrastim Before Surgery in Treating Patients With HER2-Positive Breast Cancer That Can Be Removed By Surgery

ClinicalTrials.gov

2018-02-12

Estrogen Receptor-negative Breast Cancer; Estrogen Receptor-positive Breast Cancer; HER2-positive Breast Cancer; Progesterone Receptor-negative Breast Cancer; Progesterone Receptor-positive Breast Cancer; Stage IA Breast Cancer; Stage IB Breast Cancer; Stage II Breast Cancer; Stage IIIA Breast Cancer

AFP464 in Treating Patients With Metastatic or Refractory Solid Tumors That Cannot Be Removed By Surgery

ClinicalTrials.gov

2014-02-21

Male Breast Cancer; Recurrent Breast Cancer; Recurrent Ovarian Epithelial Cancer; Recurrent Primary Peritoneal Cavity Cancer; Recurrent Renal Cell Cancer; Stage IV Breast Cancer; Stage IV Ovarian Epithelial Cancer; Stage IV Primary Peritoneal Cavity Cancer; Stage IV Renal Cell Cancer; Unspecified Adult Solid Tumor, Protocol Specific

LGE Provides Incremental Prognostic Information Over Serum Biomarkers in AL Cardiac Amyloidosis.

PubMed

Boynton, Samuel J; Geske, Jeffrey B; Dispenzieri, Angela; Syed, Imran S; Hanson, Theodore J; Grogan, Martha; Araoz, Philip A

2016-06-01

This study sought to determine the prognostic value of cardiac magnetic resonance (CMR) late gadolinium enhancement (LGE) in amyloid light chain (AL) cardiac amyloidosis. Cardiac involvement is the major determinant of mortality in AL amyloidosis. CMR LGE is a marker of amyloid infiltration of the myocardium. The purpose of this study was to evaluate retrospectively the prognostic value of CMR LGE for determining all-cause mortality in AL amyloidosis and to compare the prognostic power with the biomarker stage. Seventy-six patients with histologically proven AL amyloidosis underwent CMR LGE imaging. LGE was categorized as global, focal patchy, or none. Global LGE was considered present if it was visualized on LGE images or if the myocardium nulled before the blood pool on a cine multiple inversion time (TI) sequence. CMR morphologic and functional evaluation, echocardiographic diastolic evaluation, and cardiac biomarker staging were also performed. Subjects' charts were reviewed for all-cause mortality. Cox proportional hazards analysis was used to evaluate survival in univariate and multivariate analysis. There were 40 deaths, and the median study follow-up period was 34.4 months. Global LGE was associated with all-cause mortality in univariate analysis (hazard ratio = 2.93; p < 0.001). In multivariate modeling with biomarker stage, global LGE remained prognostic (hazard ratio = 2.43; p = 0.01). Diffuse LGE provides incremental prognosis over cardiac biomarker stage in patients with AL cardiac amyloidosis. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Number of Lymph Nodes Removed and Survival after Gastric Cancer Resection: An Analysis from the US Gastric Cancer Collaborative.

PubMed

Gholami, Sepideh; Janson, Lucas; Worhunsky, David J; Tran, Thuy B; Squires, Malcolm Hart; Jin, Linda X; Spolverato, Gaya; Votanopoulos, Konstantinos I; Schmidt, Carl; Weber, Sharon M; Bloomston, Mark; Cho, Clifford S; Levine, Edward A; Fields, Ryan C; Pawlik, Timothy M; Maithel, Shishir K; Efron, Bradley; Norton, Jeffrey A; Poultsides, George A

2015-08-01

Examination of at least 16 lymph nodes (LNs) has been traditionally recommended during gastric adenocarcinoma resection to optimize staging, but the impact of this strategy on survival is uncertain. Because recent randomized trials have demonstrated a therapeutic benefit from extended lymphadenectomy, we sought to investigate the impact of the number of LNs removed on prognosis after gastric adenocarcinoma resection. We analyzed patients who underwent gastrectomy for gastric adenocarcinoma from 2000 to 2012, at 7 US academic institutions. Patients with M1 disease or R2 resections were excluded. Disease-specific survival (DSS) was calculated using the Kaplan-Meier method and compared using log-rank and Cox regression analyses. Of 742 patients, 257 (35%) had 7 to 15 LNs removed and 485 (65%) had ≥16 LNs removed. Disease-specific survival was not significantly longer after removal of ≥16 vs 7 to 15 LNs (10-year survival, 55% vs 47%, respectively; p = 0.53) for the entire cohort, but was significantly improved in the subset of patients with stage IA to IIIA (10-year survival, 74% vs 57%, respectively; p = 0.018) or N0-2 disease (72% vs 55%, respectively; p = 0.023). Similarly, for patients who were classified to more likely be "true N0-2," based on frequentist analysis incorporating both the number of positive and of total LNs removed, the hazard ratio for disease-related death (adjusted for T stage, R status, grade, receipt of neoadjuvant and adjuvant therapy, and institution) significantly decreased as the number of LNs removed increased. The number of LNs removed during gastrectomy for adenocarcinoma appears itself to have prognostic implications for long-term survival. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Number of Lymph Nodes Removed and Survival after Gastric Cancer Resection: An Analysis from the U.S. Gastric Cancer Collaborative

PubMed Central

Gholami, Sepideh; Janson, Lucas; Worhunsky, David J.; Tran, Thuy B.; Squires, Malcolm Hart; Jin, Linda X.; Spolverato, Gaya; Votanopoulos, Konstantinos I.; Schmidt, Carl; Weber, Sharon M.; Bloomston, Mark; Cho, Clifford S.; Levine, Edward A.; Fields, Ryan C.; Pawlik, Timothy M.; Maithel, Shishir K.; Efron, Bradley; Norton, Jeffrey A.; Poultsides, George A.

2015-01-01

Background Examination of at least 16 lymph nodes (LNs) has been traditionally recommended during gastric adenocarcinoma (GAC) resection to optimize staging, but the impact of this strategy on survival is uncertain. As recent randomized trials have demonstrated a therapeutic benefit from extended lymphadenectomy, we sought to investigate the impact of the number of LNs removed on prognosis after GAC resection. Study Design Patients who underwent gastrectomy for GAC from 2000 to 2012 at seven US academic institutions were analyzed. Patients with M1 disease or R2 resections were excluded. Disease-specific survival (DSS) was calculated using the Kaplan-Meier method and compared using log-rank and Cox regression analyses. Results Of 742 patients, 257 (35%) had 7–15 LNs removed and 485 (65%) had ≥16 LNs removed. DSS was not significantly longer after removal of ≥16 versus 7–15 LNs (10-year, 55% versus 47%; P = 0.53) for the entire cohort, but was significantly improved in the subset of patients with stage IA-IIIA (10-year, 74% versus 57%; P = 0.018) or N0-2 disease (72% versus 55%, P = 0.023). Similarly, for patients who were classified to more likely be “true N0-2”, based on frequentist analysis incorporating both the number of positive and of total LNs removed, the hazard ratio for disease-related death (adjusted for T stage, R status, grade, receipt of neoadjuvant and adjuvant therapy, as well as institution) significantly decreased as the number of LNs removed increased. Conclusions The number of lymph nodes removed during gastrectomy for adenocarcinoma appears itself to have prognostic implications on long-term survival. PMID:26206635

Electric Field Tunable Microwave and MM-wave Ferrite Devices

DTIC Science & Technology

2010-04-30

xm thick YIG film grown by liquid-phase epitaxy on a (111) gadolinium gallium garnet was used. A PZT plate with the dimensions 4x1x0.5 mm3 was...of width ~ 150 micron and length 20 mm. An YIG film , 6 u.m thick, 0.5 mm in width and 2.5 mm long, grown on a 0.5 mm thick gadolinium gallium garnet ...yttrium iron garnet film and a ceramic barium strontium titanate slab. The electrical tunability of the differential phase shift Acp is achieved through

Light deflection in gadolinium molybdate ferroelastic crystals

NASA Astrophysics Data System (ADS)

Staniorowski, Piotr; Bornarel, Jean

2000-02-01

The deflection of a He-Ne light beam by polydomain gadolinium molybdate (GMO) crystals has been studied with respect to incidence angle icons/Journals/Common/alpha" ALT="alpha" ALIGN="TOP"/> i on the sample at room temperature. The A and B deflected beams do not cross each other during the icons/Journals/Common/alpha" ALT="alpha" ALIGN="TOP"/> i variation, in contrast to results and calculations previously published. The model using the Fresnel equation confirms this result. The model presented is more accurate for numerical calculation than that using the Huygens construction.

Dielectric properties and activation behavior of gadolinium doped nanocrystalline yttrium chromite

NASA Astrophysics Data System (ADS)

Sinha, R.; Basu, S.; Meikap, A. K.

2018-04-01

Gadolinium doped Yttrium Chromite nanoparticles are synthesized following sol-gel method. The formation of the nanoparticles are confirmed by XRD and TEM measurements. Dielectric permittivity and dielectric loss are estimated within the temperature range 298K to 523K and in the frequency range 20 Hz to 1 MHz. Dielectric permittivity follows the power law ɛ'(f) ∝ Tm. It is observed that the temperature exponent m increases with the decreasing frequency. The temperature variation of resistivity shows that the samples have semiconducting behavior. The activation energy is also measured.

Modification of the crystal structure of gadolinium gallium garnet by helium ion irradiation

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

Ostafiychuk, B. K.; Yaremiy, I. P., E-mail: yaremiy@rambler.ru; Yaremiy, S. I.

2013-12-15

The structure of gadolinium gallium garnet (GGG) single crystals before and after implantation by He{sup +} ions has been investigated using high-resolution X-ray diffraction methods and the generalized dynamic theory of X-ray scattering. The main types of growth defects in GGG single crystals and radiation-induced defects in the ion-implanted layer have been determined. It is established that the concentration of dislocation loops in the GGG surface layer modified by ion implantation increases and their radius decreases with an increase in the implantation dose.

Gemcitabine Hydrochloride and Eribulin Mesylate in Treating Patients With Bladder Cancer That is Advanced or Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-05-23

Metastatic Ureteral Neoplasm; Metastatic Urethral Neoplasm; Stage III Bladder Urothelial Carcinoma AJCC v6 and v7; Stage III Ureter Cancer AJCC v7; Stage III Urethral Cancer AJCC v7; Stage IV Bladder Urothelial Carcinoma AJCC v7; Stage IV Ureter Cancer AJCC v7; Stage IV Urethral Cancer AJCC v7; Ureter Urothelial Carcinoma; Urethral Urothelial Carcinoma

Akt Inhibitor MK2206, Lapatinib Ditosylate, and Trastuzumab in Treating Patients With Locally Advanced or Metastatic HER2-Positive Breast , Gastric, or Gastroesophageal Cancer That Cannot Be Removed By Surgery

ClinicalTrials.gov

2013-09-27

Adenocarcinoma of the Gastroesophageal Junction; HER2-positive Breast Cancer; Male Breast Cancer; Recurrent Breast Cancer; Recurrent Esophageal Cancer; Recurrent Gastric Cancer; Stage IIIC Breast Cancer; Stage IIIC Esophageal Cancer; Stage IIIC Gastric Cancer; Stage IV Breast Cancer; Stage IV Esophageal Cancer; Stage IV Gastric Cancer

Nivolumab With or Without Ipilimumab in Treating Patients With Metastatic Sarcoma That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-06-20

Dedifferentiated Liposarcoma; Gastrointestinal Stromal Tumor; Metastatic Liposarcoma; Metastatic Undifferentiated Pleomorphic Sarcoma; Pleomorphic Liposarcoma; Stage III Bone Sarcoma AJCC v7; Stage III Soft Tissue Sarcoma AJCC v7; Stage IV Bone Sarcoma AJCC v7; Stage IV Soft Tissue Sarcoma AJCC v7; Stage IVA Bone Sarcoma AJCC v7; Stage IVB Bone Sarcoma AJCC v7; Unresectable Liposarcoma

Surface modified α-glycine - EuF3: Gd nanoparticles for upconversion luminescence

NASA Astrophysics Data System (ADS)

Mahajan, Manoj P.; Khandpekar, M. M.

2018-04-01

Gadolinium doped EuF3 nanoparticles have been synthesized in the presence of α-glycine via chloride route with subsequent microwave drying. The XRD profile shows hexagonal phase structure with lattice parameters a = b = 6.920 A° and c = 7.085 A° (JCPDS No. 32-0373) with Debye-Scherer particle size of 51 nm. The SEM shows chipped morphology and TEM images exhibit shallow toroid like hexagonal - rounded nanostructures (30 - 50 nm) and their subsequent spontaneous transformation in to hyperboloid shaped nanostructures (200 - 600 nm) possibly with extension of the reaction time. SAED pattern confirms crystalline nature of nanoparticles and the planes are in agreement with XRD Peaks. Comparative FTTR and Raman spectrum shows presence of various functional groups confirming the capping of the glycine on EuF3:Gd core. A TGA/DTA spectrum shows decomposition in two stages. The photoluminescence spectrum shows up conversion luminescence at wavelength 653 nm (red).

Catalytic multi-stage process for hydroconversion and refining hydrocarbon feeds

DOEpatents

Comolli, Alfred G.; Lee, Lap-Keung

2001-01-01

A multi-stage catalytic hydrogenation and hydroconversion process for heavy hydrocarbon feed materials such as coal, heavy petroleum fractions, and plastic waste materials. In the process, the feedstock is reacted in a first-stage, back-mixed catalytic reactor with a highly dispersed iron-based catalyst having a powder, gel or liquid form. The reactor effluent is pressure-reduced, vapors and light distillate fractions are removed overhead, and the heavier liquid fraction is fed to a second stage back-mixed catalytic reactor. The first and second stage catalytic reactors are operated at 700-850.degree. F. temperature, 1000-3500 psig hydrogen partial pressure and 20-80 lb./hr per ft.sup.3 reactor space velocity. The vapor and light distillates liquid fractions removed from both the first and second stage reactor effluent streams are combined and passed to an in-line, fixed-bed catalytic hydrotreater for heteroatom removal and for producing high quality naphtha and mid-distillate or a full-range distillate product. The remaining separator bottoms liquid fractions are distilled at successive atmospheric and vacuum pressures, low and intermediate-boiling hydrocarbon liquid products are withdrawn, and heavier distillate fractions are recycled and further upgraded to provide additional low-boiling hydrocarbon liquid products. This catalytic multistage hydrogenation process provides improved flexibility for hydroprocessing the various carbonaceous feedstocks and adjusting to desired product structures and for improved economy of operations.

Emission control system for nitrogen oxides using enhanced oxidation, scrubbing, and biofiltration

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

Martinez, A.; Cabezas, J.

2009-05-15

Nitric oxide (NO) constitutes about 90% of the nitrogen oxide (NOx) species in the flue gases emitted from combustion processes, but NO is difficult to remove in existing scrubbers due to its low solubility. NO may be oxidized with hydrogen peroxide (H{sub 2}O{sub 2}) into soluble species that can be partially removed in wet scrubbers simultaneously with sulfur dioxide (SO{sub 2}) and biofilters located downstream of the scrubber can increase the removal efficiency. This article presents the results of a bench-scale evaluation of such an integrated system combining enhanced oxidation, scrubbing, and biofiltration. Main components of the bench-scale system consistedmore » of a quartz tube in a furnace to simulate the NO oxidation stage and two vertical packed bed cylinders constituting the scrubber and the biofilter. Inlet synthetic gas had a concentration of 50 mu L/L of NO. Overall removal efficiency by the integrated system was in the range of 53% to 93% with an average of 79%, absorption accounted for 43% and biofiltration for 36% of the total removal. Key parameters in the operation of the system are the H{sub 2}O{sub 2}:NO mole ratio, the reaction temperature, the liquid to gas flow ratio, and the biofilter residence time. Experimental results suggest a path for optimization of the technology focusing simultaneously in minimizing H{sub 2}O{sub 2} use in the enhanced oxidation stage, reducing water consumption in the scrubber stage and balancing the residence times in the three stages of the integrated system.« less

Application of Kalman filter in frequency offset estimation for coherent optical quadrature phase-shift keying communication system

NASA Astrophysics Data System (ADS)

Jiang, Wen; Yang, Yanfu; Zhang, Qun; Sun, Yunxu; Zhong, Kangping; Zhou, Xian; Yao, Yong

2016-09-01

The frequency offset estimation (FOE) schemes based on Kalman filter are proposed and investigated in detail via numerical simulation and experiment. The schemes consist of a modulation phase removing stage and Kalman filter estimation stage. In the second stage, the Kalman filters are employed for tracking either differential angles or differential data between two successive symbols. Several implementations of the proposed FOE scheme are compared by employing different modulation removing methods and two Kalman algorithms. The optimal FOE implementation is suggested for different operating conditions including optical signal-to-noise ratio and the number of the available data symbols.

Reducing false positives of microcalcification detection systems by removal of breast arterial calcifications.

PubMed

Mordang, Jan-Jurre; Gubern-Mérida, Albert; den Heeten, Gerard; Karssemeijer, Nico

2016-04-01

In the past decades, computer-aided detection (CADe) systems have been developed to aid screening radiologists in the detection of malignant microcalcifications. These systems are useful to avoid perceptual oversights and can increase the radiologists' detection rate. However, due to the high number of false positives marked by these CADe systems, they are not yet suitable as an independent reader. Breast arterial calcifications (BACs) are one of the most frequent false positives marked by CADe systems. In this study, a method is proposed for the elimination of BACs as positive findings. Removal of these false positives will increase the performance of the CADe system in finding malignant microcalcifications. A multistage method is proposed for the removal of BAC findings. The first stage consists of a microcalcification candidate selection, segmentation and grouping of the microcalcifications, and classification to remove obvious false positives. In the second stage, a case-based selection is applied where cases are selected which contain BACs. In the final stage, BACs are removed from the selected cases. The BACs removal stage consists of a GentleBoost classifier trained on microcalcification features describing their shape, topology, and texture. Additionally, novel features are introduced to discriminate BACs from other positive findings. The CADe system was evaluated with and without BACs removal. Here, both systems were applied on a validation set containing 1088 cases of which 95 cases contained malignant microcalcifications. After bootstrapping, free-response receiver operating characteristics and receiver operating characteristics analyses were carried out. Performance between the two systems was compared at 0.98 and 0.95 specificity. At a specificity of 0.98, the sensitivity increased from 37% to 52% and the sensitivity increased from 62% up to 76% at a specificity of 0.95. Partial areas under the curve in the specificity range of 0.8-1.0 were significantly different between the system without BACs removal and the system with BACs removal, 0.129 ± 0.009 versus 0.144 ± 0.008 (p<0.05), respectively. Additionally, the sensitivity at one false positive per 50 cases and one false positive per 25 cases increased as well, 37% versus 51% (p<0.05) and 58% versus 67% (p<0.05) sensitivity, respectively. Additionally, the CADe system with BACs removal reduces the number of false positives per case by 29% on average. The same sensitivity at one false positive per 50 cases in the CADe system without BACs removal can be achieved at one false positive per 80 cases in the CADe system with BACs removal. By using dedicated algorithms to detect and remove breast arterial calcifications, the performance of CADe systems can be improved, in particular, at false positive rates representative for operating points used in screening.

Genomic Sequencing in Determining Treatment in Patients With Metastatic Cancer or Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-01-22

Metastatic Neoplasm; Recurrent Neoplasm; Recurrent Non-Small Cell Lung Carcinoma; Stage IIIA Non-Small Cell Lung Cancer; Stage IIIB Non-Small Cell Lung Cancer; Stage IV Non-Small Cell Lung Cancer; Unresectable Malignant Neoplasm

76 FR 76027 - Airworthiness Directives; Pratt & Whitney Division (PW) PW4000 Series Turbofan Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-06

... performed by PW. This AD requires removing certain part number (P/N) high-pressure turbine (HPT) stage 1 and... engines, with high-pressure turbine (HPT) stage 1 airseal, part number (P/N) 50L879; HPT stage 2 airseal...

Preservation of auditory and vestibular function after surgical removal of bilateral vestibular schwannomas in a patient with neurofibromatosis type 2

NASA Technical Reports Server (NTRS)

Black, F. O.; Brackmann, D. E.; Hitselberger, W. E.; Purdy, J.

1995-01-01

The outcome of acoustic neuroma (vestibular schwannoma) surgery continues to improve rapidly. Advances can be attributed to several fields, but the most important contributions have arisen from the identification of the genes responsible for the dominant inheritance of neurofibromatosis types 1 (NF1) and 2 (NF2) and the development of magnetic resonance imaging with gadolinium enhancement for the early anatomic confirmation of the pathognomonic, bilateral vestibular schwannomas in NF2. These advances enable early diagnosis and treatment when the tumors are small in virtually all subjects at risk for NF2. The authors suggest that advising young NF2 patients to wait until complications develop, especially hearing loss, before diagnosing and operating for bilateral eighth nerve schwannomas may not always be in the best interest of the patient. To the authors' knowledge, this is the first reported case of preservation of both auditory and vestibular function in a patient after bilateral vestibular schwannoma excision.

Electrochemical Testing of Ni-Cr-Mo-Gd Alloys

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

T. E. Lister; R. E. Mizia; H. Tian

2005-10-01

The waste package site recommendation design specified a boron-containing stainless steel, Neutronit 976/978, for fabrication of the internal baskets that will be used as a corrosion-resistant neutron-absorbing material. Recent corrosion test results gave higher-than-expected corrosion rates for this material. The material callout for these components has been changed to a Ni-Cr-Mo-Gd alloy (ASTM-B 932-04, UNS N06464) that is being developed at the Idaho National Laboratory. This report discusses the results of initial corrosion testing of this material in simulated in-package environments that could contact the fuel baskets after breach of the waste package outer barrier. The corrosion test matrix wasmore » executed using the potentiodynamic and potentiostatic electrochemical test techniques. The alloy performance shows low rates of general corrosion after initial removal of a gadolinium-rich second phase that intersects the surface. The high halide-containing test solutions exhibited greater tendencies toward initiation of crevice corrosion.« less

Transient increase in the levels of gamma-tubulin complex in reorientation of cortical microtubules by gravity in azuki bean epicotyls

NASA Astrophysics Data System (ADS)

Soga, Kouichi; Kotake, Toshihisa; Wakabayashi, Kazuyuki; Kamisaka, Seiichiro; Hoson, Takayuki

Azuki bean (Vigna angularis Ohwi et Ohashi) seedlings were exposed to centrifugal hypergravity, and the changes in the orientation of cortical microtubules and the expression of genes cording γ-tubulin complex (VaTUBG and VaSpc98p) were examined. By 300 g treatment, the percentage of cells with transverse microtubules was decreased, while that with longitudinal microtubules was increased in epicotyls. Hypergravity increased the expression of VaTUBG and VaSpc98p transiently. Also, the expression of both genes was increased transiently by removal of hypergravity stimulus. Lanthanum and gadolinium ions, potential blockers of mechanosensitive calcium ion-permeable channels (mechanoreceptors), nullified reorientation of microtubules as well as up-regulation of expression of VaTUBG and VaSpc98p by hypergravity. These results suggest that mechanoreceptors on the plasma membrane may perceive the gravity signal, which leads to reorientation of cortical microtubules by transiently stimulating the formation of γ-tubulin complex.

Stage II Remedial Action Plan Deer Lake AOC

EPA Pesticide Factsheets

Michigan Department of Environmental Quality reports on actions taken that have resulted in the removal of two beneficial use impairments. Outlines plans to remove remaining BUI and to delist the Area Of Concern.

Heterogeneous selenite reduction by zero valent iron steel wool.

PubMed

Li, Ziyan; Huang, Donglin; McDonald, Louis M

2017-02-01

Mine drainage from the low-sulfur surface coal mines in southern West Virginia, USA, is circumneutral (pH > 6) but contains elevated selenium (Se) concentrations. Removal of selenite ions from aqueous solutions under anoxic condition at pH 6-8.5 by zero valent iron steel wool (ZVI-SW) was investigated in bench-scale kinetic experiments using wet chemical, microscopic and spectroscopic techniques (X-ray photoelectron spectroscopy). ZVI-SW could effectively and efficiently remove Se IV from solution with pH 6-8.5. A two-step removal mechanism was identified for Se IV reduction by ZVI-SW. The proposed mechanism was electrochemical reduction of Se IV by Fe 0 in an initial lag stage, followed by a faster heterogeneous reduction, mediated by an Fe II -bearing phase (hydroxide or green rust). Solution pH was a critical factor for the kinetic rate in the lag stage (0.33 h -1 for pH > 8 and 0.10 h -1 for pH 6-8). The length of lag stage was 20-30 min as determined by the time for dissolved Fe II concentration to reach 0.30 ± 0.04 mg L -1 which was critical for induction of the faster stage. About 65% of the initial Se IV was reduced to Se 0 , the primary reductive product in both stages.

Municipal waste liquor treatment via bioelectrochemical and fermentation (H2 + CH4) processes: Assessment of various technological sequences.

PubMed

Rózsenberszki, Tamás; Koók, László; Bakonyi, Péter; Nemestóthy, Nándor; Logroño, Washington; Pérez, Mario; Urquizo, Gladys; Recalde, Celso; Kurdi, Róbert; Sarkady, Attila

2017-03-01

In this paper, the anaerobic treatment of a high organic-strength wastewater-type feedstock, referred as the liquid fraction of pressed municipal solid waste (LPW) was studied for energy recovery and organic matter removal. The processes investigated were (i) dark fermentation to produce biohydrogen, (ii) anaerobic digestion for biogas formation and (iii) microbial fuel cells for electrical energy generation. To find a feasible alternative for LPW treatment (meeting the two-fold aims given above), various one- as well as multi-stage processes were tested. The applications were evaluated based on their (i) COD removal efficiencies and (ii) specific energy gain. As a result, considering the former aspect, the single-stage processes could be ranked as: microbial fuel cell (92.4%)> anaerobic digestion (50.2%)> hydrogen fermentation (8.8%). From the latter standpoint, an order of hydrogen fermentation (2277 J g -1  COD removed  d -1 )> anaerobic digestion (205 J g -1  COD removed  d -1 )> microbial fuel cell (0.43 J g -1  COD removed  d -1 ) was attained. The assessment showed that combined, multi-step treatment was necessary to simultaneously achieve efficient organic matter removal and energy recovery from LPW. Therefore, a three-stage system (hydrogen fermentation-biomethanation-bioelectrochemical cell in sequence) was suggested. The different approaches were characterized via the estimation of COD balance, as well. Copyright © 2016 Elsevier Ltd. All rights reserved.

Exogenous contrast agents for thermoacoustic imaging: An investigation into the underlying sources of contrast

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

Ogunlade, Olumide, E-mail: o.ogunlade@ucl.ac.uk; Beard, Paul

2015-01-15

Purpose: Thermoacoustic imaging at microwave excitation frequencies is limited by the low differential contrast exhibited by high water content tissues. To overcome this, exogenous thermoacoustic contrast agents based on gadolinium compounds, iron oxide, and single wall carbon nanotubes have previously been suggested and investigated. However, these previous studies did not fully characterize the electric, magnetic, and thermodynamic properties of these agents thus precluding identification of the underlying sources of contrast. To address this, measurements of the complex permittivity, complex permeability, DC conductivity, and Grüneisen parameter have been made. These measurements allowed the origins of the contrast provided by each substancemore » to be identified. Methods: The electric and magnetic properties of the contrast agents were characterized at 3 GHz using two rectangular waveguide cavities. The DC conductivity was measured separately using a conductivity meter. Thermoacoustic signals were then acquired and compared to those generated in water. Finally, 3D electromagnetic simulations were used to decouple the different contributions to the absorbed power density. Results: It was found that the gadolinium compounds provided appreciable electric contrast but not originating from the gadolinium itself. The contrast was either due to dissociation of the gadolinium salt which increased ionic conductivity or its nondissociated polar fraction which increased dielectric polarization loss or a combination of both. In addition, very high concentrations were required to achieve appreciable contrast, to the extent that the Grüneisen parameter increased significantly and became a source of contrast. Iron oxide particles were found to produce low but measurable dielectric contrast due to dielectric polarization loss, but this is attributed to the coating of the particles not the iron oxide. Single wall carbon nanotubes did not provide measurable contrast of any type. Conclusions: It is concluded that gadolinium based contrast agents, iron oxide particles, and single walled carbon nanotubes have little intrinsic merit as thermoacoustic contrast agents. Simple electrolytes such as saline which yield high contrast based on ionic conductivity provide much higher dielectric contrast per unit solute concentration and are likely to be significantly more effective as contrast agents.« less

Geometrically confined ultrasmall gadolinium oxide nanoparticles boost the T1 contrast ability

NASA Astrophysics Data System (ADS)

Ni, Kaiyuan; Zhao, Zhenghuan; Zhang, Zongjun; Zhou, Zijian; Yang, Li; Wang, Lirong; Ai, Hua; Gao, Jinhao

2016-02-01

High-performance magnetic resonance imaging (MRI) contrast agents and novel contrast enhancement strategies are urgently needed for sensitive and accurate diagnosis. Here we report a strategy to construct a new T1 contrast agent based on the Solomon-Bloembergen-Morgan (SBM) theory. We loaded the ultrasmall gadolinium oxide nanoparticles into worm-like interior channels of mesoporous silica nanospheres (Gd2O3@MSN nanocomposites). This unique structure endows the nanocomposites with geometrical confinement, high molecular tumbling time, and a large coordinated number of water molecules, which results in a significant enhancement of the T1 contrast with longitudinal proton relaxivity (r1) as high as 45.08 mM-1 s-1. Such a high r1 value of Gd2O3@MSN, compared to those of ultrasmall Gd2O3 nanoparticles and gadolinium-based clinical contrast agents, is mainly attributed to the strong geometrical confinement effect. This strategy provides new guidance for developing various high-performance T1 contrast agents for sensitive imaging and disease diagnosis.High-performance magnetic resonance imaging (MRI) contrast agents and novel contrast enhancement strategies are urgently needed for sensitive and accurate diagnosis. Here we report a strategy to construct a new T1 contrast agent based on the Solomon-Bloembergen-Morgan (SBM) theory. We loaded the ultrasmall gadolinium oxide nanoparticles into worm-like interior channels of mesoporous silica nanospheres (Gd2O3@MSN nanocomposites). This unique structure endows the nanocomposites with geometrical confinement, high molecular tumbling time, and a large coordinated number of water molecules, which results in a significant enhancement of the T1 contrast with longitudinal proton relaxivity (r1) as high as 45.08 mM-1 s-1. Such a high r1 value of Gd2O3@MSN, compared to those of ultrasmall Gd2O3 nanoparticles and gadolinium-based clinical contrast agents, is mainly attributed to the strong geometrical confinement effect. This strategy provides new guidance for developing various high-performance T1 contrast agents for sensitive imaging and disease diagnosis. Electronic supplementary information (ESI) available: Supplementary Fig. S1-S6. See DOI: 10.1039/c5nr08402d

Lenalidomide, Ibrutinib, and Rituximab in Treating Patients With Relapsed or Refractory Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma That Is Metastatic or Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-04-13

Ann Arbor Stage III Small Lymphocytic Lymphoma; Ann Arbor Stage IV Small Lymphocytic Lymphoma; Recurrent Chronic Lymphocytic Leukemia; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Small Lymphocytic Lymphoma; Stage III Chronic Lymphocytic Leukemia; Stage IV Chronic Lymphocytic Leukemia

Talimogene Laherparepvec and Radiation Therapy in Treating Patients With Newly Diagnosed Soft Tissue Sarcoma That Can Be Removed by Surgery

ClinicalTrials.gov

2018-05-23

FNCLCC Sarcoma Grade 2; FNCLCC Sarcoma Grade 3; Leiomyosarcoma; Liposarcoma; Stage I Soft Tissue Sarcoma AJCC v7; Stage IA Soft Tissue Sarcoma AJCC v7; Stage IB Soft Tissue Sarcoma AJCC v7; Stage II Soft Tissue Sarcoma AJCC v7; Stage IIA Soft Tissue Sarcoma AJCC v7; Stage IIB Soft Tissue Sarcoma AJCC v7; Undifferentiated Pleomorphic Sarcoma

Clinical application of a gadolinium-based capsule as an MRI contrast agent in slow transit constipation diagnostics.

PubMed

Zhi, M; Zhou, Z; Chen, H; Xiong, F; Huang, J; He, H; Zhang, M; Su, M; Gao, X; Hu, P

2017-06-01

As a traditional method for the assessment of colon dynamics, radio-opaque markers (ROMs) are limited in clinical use because of their ionizing radiation. We compared the accuracy and applicability of gadolinium-based capsules with ROMs in the measurement of colon dynamics in healthy controls and slow transit constipation (STC) patients. Seven patients with STC and nine healthy controls under a normal diet orally consumed ROMs and gadolinium-based capsules simultaneously. All subjects underwent X-ray and magnetic resonance imaging (MRI). Healthy control images were acquired at 12, 24, and 48 h, and STC patient images were acquired at 24, 48, and 72 h. The scores based on the position of the labeling capsules and ROMs in the colon and the colon transit times (CTTs) in the two groups were compared. The CTTs obtained via the ROMs were 34.7±17.4 and 67.3±6.5 h in the healthy controls and STC patients, respectively (P<.05). The CTTs obtained via MRI were 30.9±15.9 and 74.1±7.2 h in the healthy controls and STC patients, respectively (P<.05). The CTTs of the STC patients were significantly longer than the healthy controls. The correlation (r s ) between the scores based on the position of the labeling capsule and ROMs in the healthy group and the STC patients was .880 (P<.05) and .889 (P<.05), respectively. As a MRI contrast label, gadolinium-based capsules exhibit results comparable to ROMs in colon motility measurements. © 2017 John Wiley & Sons Ltd.

DAM_Explorer: A Modeling Framework for Assessing the Physical Response of Streams to Dam Removal

DTIC Science & Technology

2009-06-01

ERDC TN-EMRRP-SR-65 1 DAM_Explorer: A Modeling Framework for Assessing the Physical Response of Streams to Dam Removal By Jock Conyngham1 and...physical and temporal increments for staged removals) is anticipated. POINTS OF CONTACT For additional information contact Jock N. Conyngham (406-541

Removal of PPCPs from the sludge supernatant in a one stage nitritation/anammox process.

PubMed

Alvarino, T; Suarez, S; Katsou, E; Vazquez-Padin, J; Lema, J M; Omil, F

2015-01-01

Pharmaceutical and personal care products (PPCPs) are extensively used and can therefore find their way into surface, groundwater and municipal and industrial effluents. In this work, the occurrence, fate and removal mechanisms of 19 selected PPCPs was investigated in an 'ELiminación Autótrofa de Nitrógeno' (ELAN) reactor of 200 L. In this configuration, ammonium oxidation to nitrite and the anoxic ammonium oxidation (anammox)processes occur simultaneously in a single-stage reactor under oxygen limited conditions. The ELAN process achieved high removal (>80%) of the studied hormones, naproxen, ibuprofen, bisphenol A and celestolide, while it was not effective in the removal of carbamazepine (<7%), diazepam (<7%) and fluoxetine (<30%). Biodegradation was the dominant removal mechanism, while sorption was only observed for musk fragrances, fluoxetine and triclosan. The sorption was strongly dependent on the granule size, with smaller granules facilitating the sorption of the target compounds. Increased hydraulic retention time enhanced the intramolecular diffusion of the PPCPs into the granules, and thus increased the solid phase concentration. The increase of nitritation rate favored the removal of ibuprofen, bisphenol A and triclosan, while the removal of erythromycin was strongly correlated to the anammox reaction rate.

Investigation of gas stripping and pervaporation for improved feasibility of two-stage butanol production process.

PubMed

Setlhaku, Mpho; Heitmann, Sebastian; Górak, Andrzej; Wichmann, Rolf

2013-05-01

Gas stripping and pervaporation are investigated for butanol recovery in a two-stage acetone-butanol-ethanol (ABE) fermentation process. The first stage is operated in a continuous mode and the second stage as a fed-batch. Gas stripping coupled to the second stage and operated intermittently enabled additional glucose feeding in the second stage and up to 59 g/L butanol and 73 g/L total ABE solvents in the condensate. Concentration of 167 g/L butanol and 269 g/L ABE in the permeate was measured in ex situ pervaporation experiments using a PDMS membrane at temperature of 37 °C and pressure of 10mbars. The "operating window" tool is introduced to evaluate the feasibility of the existing ABE fermentations operated as continuous with cell recycle, as two-stages, with biomass immobilization or with integrated product removal. This tool enables the identification of the most favorable process configuration, which is the combination of cell immobilization and integrated product removal. Copyright © 2013 Elsevier Ltd. All rights reserved.

Radiation methods for demercaptanization and desulfurization of oil products

NASA Astrophysics Data System (ADS)

Zaykina, R. F.; Zaykin, Yu. A.; Mamonova, T. B.; Nadirov, N. K.

2002-03-01

A two-stage method for the desulfurization of oil is presented. The first stage strongly oxidizes sulfuric material to do away with its chemical aggressiveness and promote its removal. Desulfurization of the overall product is reached at the second stage by means of conventional methods.

Paclitaxel With or Without Carboplatin and/or Bevacizumab Followed by Doxorubicin and Cyclophosphamide in Treating Patients With Breast Cancer That Can Be Removed by Surgery

ClinicalTrials.gov

2018-03-29

Estrogen Receptor Negative; HER2/Neu Negative; Male Breast Carcinoma; Progesterone Receptor Negative; Stage IIA Breast Cancer; Stage IIB Breast Cancer; Stage IIIA Breast Cancer; Triple-Negative Breast Carcinoma

Gadolinium-hydrogen ion exchange of zirconium phosphate

NASA Technical Reports Server (NTRS)

Liu, D. C.; Power, J. L.

1972-01-01

The Gd(+3)/H(+) ion exchange on a commercial zirconium phosphate ion exchanger was investigated in chloride, sulfate, and phosphate solutions of Gd(+3) at gadolinium concentrations of 0.001 to 1 millimole per cc and in the pH range of 0 to 3.5. Relatively low Gd(+3) capacities, in the range of 0.01 to 0.1 millimole per g of ion exchanger were found at room temperature. A significant difference in Gd(+3) sorption was observed, depending on whether the ion exchanger was converted from initial conditions of greater or lesser Gd(+3) sorption than the specific final conditions. Correlations were found between decrease in Gd(+3) capacity and loss of exchanger phosphate groups due to hydrolysis during washing and between increase in capacity and treatment with H3PO4. Fitting of the experimental data to ideal ion exchange equilibrium expressions indicated that each Gd(+3) ion is sorbed on only one site of the ion exchanger. The selectivity quotient was determined to be 2.5 + or - 0.4 at room temperature on gadolinium desorption in chloride solutions.

Comparative theoretical study of the structures and stabilities of four typical gadolinium carboxylates in different scintillator solvents.

PubMed

Huang, Pin-Wen

2016-03-01

The structural properties and stabilities of four typical gadolinium carboxylates (Gd-CBX) in toluene, linear alkyl benzene (LAB), and phenyl xylyl ethane (PXE) solvents were theoretically studied using density functional theory (DFT/B3LYP with the basis sets 6-311G(d) and MWB54) and the polarizable continuum model (PCM). The average Gd-ligand interaction energies (E int, corrected for dispersion) and the values of the energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital (ΔHL) for the gadolinium complexes were calculated to compare the relative stabilities of the four Gd-CBX molecules in the three liquid scintillator solvents. According to the calculations, the values of E int and ΔHL for Gd-CBX in LAB are larger than the corresponding values in PXE and toluene. Gd-CBX may therefore be more compatible with LAB than with PXE and toluene. It was also found that, in the three scintillator solvents, the stabilities of the four Gd-CBX molecules increase in the order Gd-2EHA < Gd-2MVA < Gd-pivalate < Gd-TMHA.

Right ventricular stress-induced perfusion defects and late gadolinium enhancement in coronary artery disease.

PubMed

Milks, Michael Wesley; Upadhya, Bharathi; Hall, Michael E; Vasu, Sujethra; Hundley, William Gregory; Stacey, Richard Brandon

2015-01-01

The assessment of right ventricular (RV) perfusion defects has remained challenging during vasodilator stress perfusion with cardiovascular magnetic resonance (CMR). The significance of RV signal abnormalities during vasodilator stress perfusion and late gadolinium-enhanced CMR is yet uncertain. Among 61 individuals who underwent adenosine CMR stress testing before cardiac catheterization, we assessed the severity of coronary artery stenoses, mortality, the presence of stress and rest perfusion defects, as well as the presence of late gadolinium enhancement (LGE). Right ventricular stress-induced perfusion defects were positively associated with left anterior descending artery and proximal right coronary artery stenoses but were negatively associated with left circumflex artery stenoses. The presence of RVLGE was associated with mortality, but 77% of those with RVLGE also had left ventricular LGE. Proximal right coronary artery and left anterior descending artery stenoses are positively associated, whereas left circumflex artery stenoses are negatively associated with RV stress-induced perfusion defects. Right ventricular LGE was associated with mortality, but further study is needed to determine whether this is independent of left ventricular LGE.

Rare-earth doped gadolinia based phosphors for potential multicolor and white light emitting deep UV LEDs.

PubMed

Bedekar, Vinila; Dutta, Dimple P; Mohapatra, M; Godbole, S V; Ghildiyal, R; Tyagi, A K

2009-03-25

Gadolinium oxide host and europium/dysprosium/terbium doped gadolinium oxide nanoparticles were synthesized using the sonochemical technique. Gadolinium oxide nanocrystals were also co-doped with total 2 mol% of Eu(3+)/Dy(3+),Eu(3+)/Tb(3+),Dy(3+)/Tb(3+), and also Eu(3+)/Dy(3+)/Tb(3+) ions, by the same method. The nanoparticles obtained were characterized using powder x-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) techniques. The size of the particles ranged from 15 to 30 nm. The triple doped samples showed multicolor emission on single wavelength excitation. The photoluminescence results were correlated with the lifetime data to get an insight into the luminescence and energy transfer processes taking place in the system. On excitation at 247 nm, the novel nanocrystalline Gd(2)O(3):RE (RE = Dy, Tb) phosphor resulted in having very impressive CIE chromaticity coordinates of x = 0.315 and y = 0.316, and a correlated color temperature of 6508 K, which is very close to standard daylight.

Effect of solid-phase amorphization on the spectral characteristics of europium-doped gadolinium molybdate

NASA Astrophysics Data System (ADS)

Shmurak, S. Z.; Kiselev, A. P.; Kurmasheva, D. M.; Red'Kin, B. S.; Sinitsyn, V. V.

2010-05-01

A method is proposed for detecting spectral characteristics of optically inactive molybdates of rare-earth elements by their doping with rare-earth ions whose luminescence lies in the transparency region of all structural modifications of the sample. Gadolinium molybdate is chosen as the object of investigations, while europium ions are used as an optically active and structurally sensitive admixture. It is shown that after the action of a high pressure under which gadolinium molybdate passes to the amorphous state, the spectral characteristics of Gd1.99Eu0.01(MoO4)3 (GMO:Eu) change radically; namely, considerable line broadening is observed in the luminescence spectra and the luminescence excitation spectra, while the long-wave threshold of optical absorption is shifted considerably (by approximately 1.1 eV) towards lower energies. It is found that by changing the structural state of GMO:Eu by solid-state amorphization followed by annealing, the spectral characteristics of the sample can be purposefully changed. This is extremely important for solving the urgent problem of designing high-efficiency light-emitting diodes producing “white” light.

Ultrasonically enhanced fractionation of milk fat in a litre-scale prototype vessel.

PubMed

Leong, Thomas; Johansson, Linda; Mawson, Raymond; McArthur, Sally L; Manasseh, Richard; Juliano, Pablo

2016-01-01

The ultrasonic fractionation of milk fat in whole milk to fractions with distinct particle size distributions was demonstrated using a stage-based ultrasound-enhanced gravity separation protocol. Firstly, a single stage ultrasound gravity separation was characterised after various sonication durations (5-20 min) with a mass balance, where defined volume partitions were removed across the height of the separation vessel to determine the fat content and size distribution of fat droplets. Subsequent trials using ultrasound-enhanced gravity separation were carried out in three consecutive stages. Each stage consisted of 5 min sonication, with single and dual transducer configurations at 1 MHz and 2 MHz, followed by aliquot collection for particle size characterisation of the formed layers located at the bottom and top of the vessel. After each sonication stage, gentle removal of the separated fat layer located at the top was performed. Results indicated that ultrasound promoted the formation of a gradient of vertically increasing fat concentration and particle size across the height of the separation vessel, which became more pronounced with extended sonication time. Ultrasound-enhanced fractionation provided fat enriched fractions located at the top of the vessel of up to 13 ± 1% (w/v) with larger globules present in the particle size distributions. In contrast, semi-skim milk fractions located at the bottom of the vessel as low as 1.2 ± 0.01% (w/v) could be produced, containing proportionally smaller sized fat globules. Particle size differentiation was enhanced at higher ultrasound energy input (up to 347 W/L). In particular, dual transducer after three-stage operation at maximum energy input provided highest mean particle size differentiation with up to 0.9 μm reduction in the semi-skim fractions. Higher frequency ultrasound at 2 MHz was more effective in manipulating smaller sized fat globules retained in the later stages of skimming than 1 MHz. While 2 MHz ultrasound removed 59 ± 2% of the fat contained in the initial sample, only 47 ± 2% was removed with 1 MHz after 3 ultrasound-assisted fractionation stages. Copyright © 2015 Elsevier B.V. All rights reserved.

Gadolinium-Based Contrast Agents in Kidney Disease: Comprehensive Review and Clinical Practice Guideline Issued by the Canadian Association of Radiologists.

PubMed

Schieda, Nicola; Blaichman, Jason I; Costa, Andreu F; Glikstein, Rafael; Hurrell, Casey; James, Matthew; Jabehdar Maralani, Pejman; Shabana, Wael; Tang, An; Tsampalieros, Anne; van der Pol, Christian; Hiremath, Swapnil

2018-05-01

Use of gadolinium-based contrast agents (GBCAs) in renal impairment is controversial, with physician and patient apprehension in acute kidney injury (AKI), chronic kidney disease (CKD), and dialysis because of concerns regarding nephrogenic systemic fibrosis (NSF). The position that GBCAs are absolutely contraindicated in AKI, CKD stage 4 or 5 (estimated glomerular filtration rate [eGFR] <30 mL/min/1.73 m 2 ) and dialysis-dependent patients is outdated, and may limit access to clinically necessary contrast-enhanced MRI examinations. Following a comprehensive review of the literature and reported NSF cases to date, a committee of radiologists and nephrologists developed clinical practice guidelines to assist physicians in making decisions regarding GBCA administrations. In patients with mild-to-moderate CKD (eGFR ≥30 and <60 mL/min/1.73 m 2 ), administration of standard doses of GBCA is safe and no additional precautions are necessary. In patients with AKI, with severe CKD (eGFR <30 mL/min/1.73 m 2 ), or on dialysis, administration of GBCAs should be considered individually and alternative imaging modalities utilized whenever possible. If GBCAs are necessary, newer GBCAs may be administered with patient consent obtained by a physician (or their delegate), citing an exceedingly low risk (much less than 1%) of developing NSF. Standard GBCA dosing should be used; half or quarter dosing is not recommended and repeat injections should be avoided. Dialysis-dependent patients should receive dialysis; however, initiating dialysis or switching from peritoneal to hemodialysis to reduce the risk of NSF is unproven. Use of a macrocyclic ionic instead of macrocyclic nonionic GBCA or macrocyclic instead of newer linear GBCA to further prevent NSF is unproven. Gadopentetate dimeglumine, gadodiamide, and gadoversetamide remain absolutely contraindicated in patients with AKI, with stage 4 or 5 CKD, or on dialysis. The panel agreed that screening for renal disease is important but less critical when using macrocyclic and newer linear GBCAs. Monitoring for and reporting of potential cases of NSF in patients with AKI or CKD who have received GBCAs is recommended. Copyright © 2017 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

Surface-flow constructed wetlands dominated by Cladophora for reclaiming nutrients in diffuse domestic effluent.

PubMed

Zhu, Huaqing; Lu, Xiwu; Dai, Hongliang

2018-03-01

In this work, a surface-flow constructed wetland (SFCW) dominated by Cladophora was used to remove and reclaim nutrients in diffuse domestic effluent (DDE) discharged from rural regions around Taihu Lake, a eutrophic shallow lake in China. Growth rate of Cladophora was investigated and linked to ambient factors and nutrient consuming rates. The growth performances of Cladophora and animal-feed microbes were studied during the commissioning of SFCW. Results show that the growth rate of Cladophora was closely correlated with field temperature and surface irradiance, while surface coverage was suitable for the manipulation of SFCW. Harvest of Cladophora along with animal-feed microbes and removal of nutrients in DDE could be achieved by manipulating surface coverage to drag growth rate back at the end of linear zone and to quickly restore Cladophora biomass in the mid zone of surface growth rate. Among four stages of the commissioning, concentrating stage experienced the majority species of animal-feed microbes and maximal nutrient removal; during decomposing stage, however, the reproduction of animal-feed microbes and nutrient removal were lower, whereas the density of pathogens was higher. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dabrafenib, Trametinib, and Navitoclax in Treating Patients With BRAF Mutant Melanoma or Solid Tumors That Are Metastatic or Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-05-21

BRAF V600E Mutation Present; BRAF V600K Mutation Present; Metastatic Melanoma; Solid Neoplasm; Stage III Cutaneous Melanoma AJCC v7; Stage IIIA Cutaneous Melanoma AJCC v7; Stage IIIB Cutaneous Melanoma AJCC v7; Stage IIIC Cutaneous Melanoma AJCC v7; Stage IV Cutaneous Melanoma AJCC v6 and v7

Sunitinib in Treating Patients With Thyroid Cancer That Did Not Respond to Iodine I 131 and Cannot Be Removed by Surgery

ClinicalTrials.gov

2017-08-18

Recurrent Thyroid Gland Carcinoma; Stage III Thyroid Gland Follicular Carcinoma; Stage III Thyroid Gland Medullary Carcinoma; Stage IV Thyroid Gland Follicular Carcinoma; Stage IV Thyroid Gland Medullary Carcinoma; Stage IV Thyroid Gland Papillary Carcinoma; Stage IVA Thyroid Gland Follicular Carcinoma; Stage IVA Thyroid Gland Medullary Carcinoma; Stage IVA Thyroid Gland Papillary Carcinoma; Stage IVB Thyroid Gland Follicular Carcinoma; Stage IVB Thyroid Gland Medullary Carcinoma; Stage IVB Thyroid Gland Papillary Carcinoma; Stage IVC Thyroid Gland Follicular Carcinoma; Stage IVC Thyroid Gland Medullary Carcinoma; Stage IVC Thyroid Gland Papillary Carcinoma; Thyroid Gland Oncocytic Follicular Carcinoma

Pilot Trial of CRLX101 in Treatment of Patients With Advanced or Metastatic Stomach, Gastroesophageal, or Esophageal Cancer That Cannot be Removed by Surgery

ClinicalTrials.gov

2018-01-08

Adenocarcinoma of the Esophagus; Adenocarcinoma of the Gastroesophageal Junction; Diffuse Adenocarcinoma of the Stomach; Intestinal Adenocarcinoma of the Stomach; Mixed Adenocarcinoma of the Stomach; Recurrent Esophageal Cancer; Recurrent Gastric Cancer; Squamous Cell Carcinoma of the Esophagus; Stage IIIB Esophageal Cancer; Stage IIIB Gastric Cancer; Stage IIIC Esophageal Cancer; Stage IIIC Gastric Cancer; Stage IV Esophageal Cancer; Stage IV Gastric Cancer

Crizotinib in Treating Patients With Stage IB-IIIA Non-small Cell Lung Cancer That Has Been Removed by Surgery and ALK Fusion Mutations (An ALCHEMIST Treatment Trial)

ClinicalTrials.gov

2017-12-07

ALK Gene Rearrangement; ALK Gene Translocation; ALK Positive; Stage IB Non-Small Cell Lung Carcinoma AJCC v7; Stage II Non-Small Cell Lung Cancer AJCC v7; Stage IIA Non-Small Cell Lung Carcinoma AJCC v7; Stage IIB Non-Small Cell Lung Carcinoma AJCC v7; Stage IIIA Non-Small Cell Lung Cancer AJCC v7

Process and system for removing sulfur from sulfur-containing gaseous streams

DOEpatents

Basu, Arunabha; Meyer, Howard S.; Lynn, Scott; Leppin, Dennis; Wangerow, James R.

2012-08-14

A multi-stage UCSRP process and system for removal of sulfur from a gaseous stream in which the gaseous stream, which contains a first amount of H.sub.2S, is provided to a first stage UCSRP reactor vessel operating in an excess SO.sub.2 mode at a first amount of SO.sub.2, producing an effluent gas having a reduced amount of SO.sub.2, and in which the effluent gas is provided to a second stage UCSRP reactor vessel operating in an excess H.sub.2S mode, producing a product gas having an amount of H.sub.2S less than said first amount of H.sub.2S.

A novel PSB-EDI system for high ammonia wastewater treatment, biomass production and nitrogen resource recovery: PSB system.

PubMed

Wang, Hangyao; Zhou, Qin; Zhang, Guangming; Yan, Guokai; Lu, Haifeng; Sun, Liyan

A novel process coupling photosynthetic bacteria (PSB) with electrodeionization (EDI) treatment was proposed to treat high ammonia wastewater and recover bio-resources and nitrogen. The first stage (PSB treatment) was used to degrade organic pollutants and accumulate biomass, while the second stage (EDI) was for nitrogen removal and recovery. The first stage was the focus in this study. The results showed that using PSB to transform organic pollutants in wastewater into biomass was practical. PSB could acclimatize to wastewater with a chemical oxygen demand (COD) of 2,300 mg/L and an ammonia nitrogen (NH4(+)-N) concentration of 288-4,600 mg/L. The suitable pH was 6.0-9.0, the average COD removal reached 80%, and the biomass increased by an average of 9.16 times. The wastewater COD removal was independent of the NH4(+)-N concentration. Moreover, the PSB functioned effectively when the inoculum size was only 10 mg/L. The PSB-treated wastewater was then further handled in an EDI system. More than 90% of the NH4(+)-N was removed from the wastewater and condensed in the concentrate, which could be used to produce nitrogen fertilizer. In the whole system, the average NH4(+)-N removal was 94%, and the average NH4(+)-N condensing ratio was 10.0.

Prognostic significance of number of nodes removed in patients with node-negative early cervical cancer.

PubMed

Mao, Siyue; Dong, Jun; Li, Sheng; Wang, Yiqi; Wu, Peihong

2016-10-01

The aim of this study was to investigate whether the number of removed lymph nodes was associated with survival of patients with node-negative early cervical cancer and to analyze the prognostic significance of clinical and pathologic features in these patients. Patients with FIGO stage IA-IIB cervical cancer who underwent radical hysterectomy with lymphadenectomy without receiving preoperative therapy were reviewed retrospectively. Patients were all proved to have lymph-node-negative disease and classified into five groups based on the number of nodes removed. The Kaplan-Meier method and Cox's proportional hazards regression model were used in prognostic analysis. The final dataset included 359 patients: 45 (12.5%) patients had ≤10 nodes removed, 93 (25.9%) had 11-15, 98 (27.3%) had 16-20, 64 (17.8%) had 21-25, and 59 (16.4%) had >25 nodes removed. There was no association between the number of nodes removed and survival of patients with node-negative early cervical cancer (χ 2  = 6.19, P = 0.185). Similarly, subgroup analyses for FIGO stage IB1-IIB also showed that the number of lymph nodes was not significantly related to survival in each stage. Multivariate analyses showed that histology and depth of invasion were independent prognostic factors for survival in these patients. If a standardized lymphadenectomy is performed, the number of lymph nodes removed is not an independent prognostic factor for patients with node-negative early cervical cancer. Our study suggests that there is inconclusive evidence to support survival benefit of complete lymphadenectomy among these patients. © 2016 Japan Society of Obstetrics and Gynecology.

Caustic Precipitation of Plutonium Using Gadolinium as the Neutron Poison for Disposition to High Level Waste

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

Bronikowski, M.G.

2002-06-24

Nuclear Materials Management Division (NMMD) has proposed that up to 100 kg of the plutonium (Pu) solutions stored in H-Canyon be precipitated with a nuclear poison and dispositioned to H-Area Tank Farm. The use of gadolinium (Gd) as the poison would greatly reduce the number of additional glass logs resulting from this disposition. This report summarizes the characteristics of the precipitation process and addresses criticality concerns in the Nuclear Criticality Safety Evaluation. No problems were found with the nature of the precipitate or the neutralization process.

Measuring θ13 in the Double Chooz experiment

NASA Astrophysics Data System (ADS)

Crum, Keith

2013-04-01

Double Chooz measures θ13 by searching for the disappearance of reactor electron antineutrinos (νe) interacting via inverse beta decay (IBD) in a liquid scintillator-based detector. The signature of IBD is the coincidence of positron annihilation followed by the capture of a neutron. Although Double Chooz was primarily designed to detect νe by searching for neutron capture on gadolinium, we can also search for neutron capture on hydrogen. We developed separate analyses for neutron capture on hydrogen and gadolinium as the two elements have different capture energies, capture lifetimes, and spatial distributions within our detector.

Active extravasation of gadolinium-based contrast agent into the subdural space following lumbar puncture.

PubMed

Kothari, Pranay D; Hanser, Evelyn M; Wang, Harrison; Farid, Nikdokht

2016-01-01

A 38year-old male presented with cauda equina syndrome following multiple lumbar puncture attempts. Lumbar spine magnetic resonance imaging (MRI) showed a subdural hematoma and an area of apparent contrast enhancement in the spinal canal on sagittal post-contrast images. Axial post-contrast images obtained seven minutes later demonstrated an increase in size and change in shape of the region of apparent contrast enhancement, indicating active extravasation of the contrast agent. This is the first reported case of active extravasation of gadolinium-based contrast agent in the spine. Copyright © 2016 Elsevier Inc. All rights reserved.

The histological basis of late gadolinium enhancement cardiovascular magnetic resonance in a patient with Anderson-Fabry disease.

PubMed

Moon, James C; Sheppard, Mary; Reed, Emma; Lee, Phillip; Elliott, Perry M; Pennell, Dudley J

2006-01-01

Anderson-Fabry Disease (AFD) is a storage disease that mimics hypertrophic cardiomyopathy. Late gadolinium enhancement (LGE) by cardiovascular magnetic resonance occurs in approximately 50% of patients in the basal inferolateral LV wall, but how an intracellular storage disease causes focal LGE is unknown. We present a whole-heart histological validation that LGE is caused by focal myocardial collagen scarring. This scarring may be the substrate for electrical re-entry and sudden arrhythmic death. The reasons for this distribution of fibrosis are unclear, but may reflect inhomogeneous left ventricular wall stress.

Gadolinium(III)-sensitized fluorescence of europium in its mixed-metal compounds with trifluroacetate

NASA Astrophysics Data System (ADS)

Kalinovskaya, I. V.; Zadorozhnaya, A. N.

2017-04-01

The fluorescence properties of mixed-metal compounds of Eu(III) and Gd(III) with trifluoroacetic acid, Eu1-хGdx(С2F3O2)3·yD·zH2O, where D - 1,10-phenanthroline, 2,2-dipyridil, diphenylguanidine, x = 0, 0.25, 0.5, or 0.7, were studied. Luminescence spectroscopic evidence and the examination of excitation spectra indicate the occurrence of efficient energy transfer from the gadolinium to the europium ion. The greatest promotion of Eu3+ photoluminescence at 615 nm is observed when Eu:Gd = 1:1.

Practical and efficient magnetic heat pump

NASA Technical Reports Server (NTRS)

Brown, G. V.

1978-01-01

Method for pumping heat magnetically at room temperature is more economical than existing refrigeration systems. Method uses natural magneto-thermal effect of gadolinium metal to establish temperature gradient across length of tube. Regenerative cyclic process in which gadolinium sample is magnetized and gives off heat at one end of tube, and then is demagnetized at other end to absorb heat has established temperature gradients of 144 degrees F in experiments near room temperature. Other materials with large magnetothermal effects can be used below room temperature. Possible commercial applications include freeze-drying and food processing, cold storage, and heating and cooling of buildings, plants, and ships.

Band-gap modulation via gallium substitution in cerium doped gadolinium aluminum garnet using a mixed fuel combustion approach

NASA Astrophysics Data System (ADS)

Tyagi, Mohit; Pitale, Shreyas S.; Ghosh, Manoranjan; Shinde, Seema

2014-04-01

Cerium doped Gadolinium garnets (Gd3AlxGa5-xO12 where 0≤x≤5) are synthesized via combustion synthesis using mixture of urea and glycine fuels. A 4h Post annealing at 1400 oC is found to be necessary for pure phase formation. Lattice spacing variation as a result of partial or total Ga substitution at Al site was mapped by X-ray diffraction. Photoluminescence emission of Ce shifts as a consequence of Ga substitution and therefore suggests a local re-adjustment of crystal field around activator site.

Highly transparent cerium doped gadolinium gallium aluminum garnet ceramic prepared with precursors fabricated by ultrasonic enhanced chemical co-precipitation.

PubMed

Zhang, Ji-Yun; Luo, Zhao-Hua; Jiang, Hao-Chuan; Jiang, Jun; Chen, Chun-Hua; Zhang, Jing-Xian; Gui, Zhen-Zhen; Xiao, Na

2017-11-01

Cerium doped gadolinium gallium aluminum garnet (GGAG:Ce) ceramic precursors have been synthesized with an ultrasonic chemical co-precipitation method (UCC) and for comparison with a traditional chemical co-precipitation method (TCC). The effect of ultra-sonication on the morphology of powders and the transmittance of GGAG:Ce ceramics are studied. The results indicate that the UCC method can effectively improve the homogenization and sinterability of GGAG:Ce powders, which contribute to obtain high transparent GGAG ceramic with the highest transmittance of 81%. Copyright © 2017 Elsevier B.V. All rights reserved.

Endometrial cancer: magnetic resonance imaging.

PubMed

Manfredi, R; Gui, B; Maresca, G; Fanfani, F; Bonomo, L

2005-01-01

Carcinoma of the endometrium is the most common invasive gynecologic malignancy of the female genital tract. Clinically, patients with endometrial carcinoma present with abnormal uterine bleeding. The role of magnetic resonance imaging (MRI) in endometrial carcinoma is disease staging and treatment planning. MRI has been shown to be the most valuable imaging mod-ality in this task, compared with endovaginal ultrasound and computed tomography, because of its intrinsic contrast resolution and multiplanar capability. MRI protocol includes axial T1-weighted images; axial, sagittal, and coronal T2-weighted images; and dynamic gadolinium-enhanced T1-weighted imaging. MR examination is usually performed in the supine position with a phased array multicoil using a four-coil configuration. Endometrial carcinoma is isointense with the normal endometrium and myometrium on noncontrast T1-weighted images and has a variable appearance on T2-weighted images demonstrating heterogeneous signal intensity. The appearance of noninvasive endometrial carcinoma on MRI is characterized by a normal or thickened endometrium, with an intact junctional zone and a sharp tumor-myometrium interface. Invasive endometrial carcinoma is characterized disruption or irregularity of the junctional zone by intermediate signal intensity mass on T2-weighted images. Invasion of the cervical stroma is diagnosed when the low signal intensity cervical stroma is disrupted by the higher signal intensity endometrial carcinoma. MRI in endometrial carcinoma performs better than other imaging modalities in disease staging and treatment planning. Further, the accuracy and the cost of MRI are equivalent to those of surgical staging.

Impact of the Glymphatic System on the Kinetic and Distribution of Gadodiamide in the Rat Brain: Observations by Dynamic MRI and Effect of Circadian Rhythm on Tissue Gadolinium Concentrations.

PubMed

Taoka, Toshiaki; Jost, Gregor; Frenzel, Thomas; Naganawa, Shinji; Pietsch, Hubertus

2018-04-12

The glymphatic system is a recently hypothesized waste clearance system of the brain in which perivascular space constitutes a pathway similar to the lymphatic system in other body regions. Sleep and anesthesia are reported to influence the activity of the glymphatic system. Because rats are nocturnal animals, the glymphatic system is expected to be more active during the day. We attempted to elucidate the influence of the glymphatic system for intravenously injected gadodiamide in the rat brain by 2 experiments. One was a magnetic resonance imaging (MRI) experiment to evaluate the short-term dynamics of signal intensity changes after gadodiamide administration. The other was a quantification experiment to evaluate the concentration of retained gadolinium within the rat brain after repeated intravenous administration of gadodiamide at different times of day and levels of anesthesia. The imaging experiment was performed on 6 rats that received an intravenous injection of gadodiamide (1 mmol/kg) and dynamic MRI for 3 hours at 2.4-minute intervals. The time course of the signal intensity changes was evaluated for different brain structures. The tissue quantification experiment was performed on 24 rats divided into 4 groups by injection time (morning, late afternoon) and anesthesia (none, short, long) during administration. All animals received gadodiamide (1.8 mmol/kg, 8 times over 2 weeks). Gadolinium concentration of dissected brain tissues was quantified 5 weeks after the last administration by inductively coupled plasma mass spectrometry. In the imaging experiment, muscle and the fourth ventricle showed an instantaneous signal intensity increase immediately after gadodiamide injection. The signal curve of the cerebral cortex and deep cerebellar nuclei reached the peak signal intensity later than the fourth ventricle but earlier than that of the prepontine cistern. In the gadolinium quantification experiment, the concentration in the group with the morning injection showed a significantly lower concentration than the late afternoon injection group. The lowest tissue gadolinium concentrations were found in the groups injected in the morning during long anesthesia. Instantaneous transition of gadodiamide from blood to cerebrospinal fluid was indicated by dynamic MRI. The gadodiamide distribution to the cerebral cortex and deep cerebellar nuclei seemed to depend on both blood flow and cerebrospinal fluid. This confirms previous studies indicating that the cerebrospinal fluid is one potential pathway of gadolinium-based contrast agent entry into the brain. For the distribution and clearance of the gadodiamide from brain tissue, involvement of the glymphatic system seemed to be indicated in terms of the influence of sleep and anesthesia.

Effect of kangaroo mother care vs expressed breast milk administration on pain associated with removal of adhesive tape in very low birth weight neonates: a randomized controlled trial.

PubMed

Nanavati, Ruchi N; Balan, Rajiv; Kabra, Nandkishor S

2013-11-08

To compare the pain relief effect of Kangaroo Mother Care (KMC) and Expressed Breast Milk (EBM) on the pain associated with adhesive tape removal in very low birth weight (VLBW) neonates. Randomized Controlled Trial. Neonatal intensive care unit of a tertiary care teaching hospital. 15 VLBW neonates who needed adhesive tape removal for the first part and 50 VLBW neonates needing adhesive tape removal for the second part. In first stage of the study, we studied whether adhesive tape removal in VLBW neonates was painful. In the second stage, eligible VLBW neonates were randomised to compare the efficacy of KMC and EBM in reducing the pain during the procedure of adhesive tape removal. Premature Infant Pain Profile (PIPP) Score, heart rate, oxygen saturation. There was significant increase in pain associated with the removal of adhesive tape (Mean pre-procedure PIPP score 3.47 ± 0.74; post-procedure mean PIPP score 12.13 ± 2.59; P<0.0001). The post intervention mean PIPP pain score was not significantly different between the KMC and EBM groups (P= 0.62). Removal of adhesive tape is a painful procedure for VLBW neonates. There was no difference between KMC and EBM in relieving pain associated with adhesive tape removal.

Enhanced nitrogen removal from electroplating tail wastewater through two-staged anoxic-oxic (A/O) process.

PubMed

Yan, Xinmei; Zhu, Chunyan; Huang, Bin; Yan, Qun; Zhang, Guangsheng

2018-01-01

Consisted of anaerobic (ANA), anoxic-1 (AN1), aerobic-1 (AE1), anoxic-2 (AN2), aerobic-2 (AE2) reactors and sediment tank, the two-staged A/O process was applied for depth treatment of electroplating tail wastewater with high electrical conductivity and large amounts of ammonia nitrogen. It was found that the NH 4 + -N and COD removal efficiencies reached 97.11% and 83.00%, respectively. Besides, the short-term salinity shock of the control, AE1 and AE2 indicated that AE1 and AE2 have better resistance to high salinity when the concentration of NaCl ranged from 1 to 10g/L. Meanwhile, it was found through high-throughput sequencing that bacteria genus Nitrosomonas, Nitrospira and Thauera, which are capable of nitrogen removal, were enriched in the two-staged A/O process. Moreover, both salt-tolerant bacteria and halophili bacteria were also found in the combined process. Therefore, microbial community within the two-staged A/O process could be acclimated to high electrical conductivity, and adapted for electroplating tail wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characteristics of back corona discharge in a honeycomb catalyst and its application for treatment of volatile organic compounds.

PubMed

Feng, Fada; Zheng, Yanyan; Shen, Xinjun; Zheng, Qinzhen; Dai, Shaolong; Zhang, Xuming; Huang, Yifan; Liu, Zhen; Yan, Keping

2015-06-02

The main technical challenges for the treatment of volatile organic compounds (VOCs) with plasma-assisted catalysis in industrial applications are large volume plasma generation under atmospheric pressure, byproduct control, and aerosol collection. To solve these problems, a back corona discharge (BCD) configuration has been designed to evenly generate nonthermal plasma in a honeycomb catalyst. Voltage-current curves, discharge images, and emission spectra have been used to characterize the plasma. Grade particle collection results and flow field visualization in the discharge zones show not only that the particles can be collected efficiently, but also that the pressure drop of the catalyst layer is relatively low. A three-stage plasma-assisted catalysis system, comprising a dielectric barrier discharge (DBD) stage, BCD stage, and catalyst stage, was built to evaluate toluene treatment performance by BCD. The ozone analysis results indicate that BCD enhances the ozone decomposition by collecting aerosols and protecting the Ag-Mn-O catalyst downstream from aerosol contamination. The GC and FTIR results show that BCD contributes to toluene removal, especially when the specific energy input is low, and the total removal efficiency reaches almost 100%. Furthermore, this removal results in the emission of fewer byproducts.

Direct liquefaction proof-of-concept facility

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

Alfred G. Comolli; Peizheng Zhou; HTI Staff

2000-01-01

The main objective of the U.S. DOE, Office of Fossil Energy, is to ensure the US a secure energy supply at an affordable price. An integral part of this program was the demonstration of fully developed coal liquefaction processes that could be implemented if market and supply considerations so required, Demonstration of the technology, even if not commercialized, provides a security factor for the country if it is known that the coal to liquid processes are proven and readily available. Direct liquefaction breaks down and rearranges complex hydrocarbon molecules from coal, adds hydrogen, and cracks the large molecules to thosemore » in the fuel range, removes hetero-atoms and gives the liquids characteristics comparable to petroleum derived fuels. The current processes being scaled and demonstrated are based on two reactor stages that increase conversion efficiency and improve quality by providing the flexibility to adjust process conditions to accommodate favorable reactions. The first stage conditions promote hydrogenation and some oxygen, sulfur and nitrogen removal. The second stage hydrocracks and speeds the conversion to liquids while removing the remaining sulfur and nitrogen. A third hydrotreatment stage can be used to upgrade the liquids to clean specification fuels.« less

Trametinib or Combination Chemotherapy in Treating Patients With Refractory or Advanced Biliary or Gallbladder Cancer or That Cannot Be Removed by Surgery

ClinicalTrials.gov

2017-08-11

Adult Cholangiocarcinoma; Advanced Adult Hepatocellular Carcinoma; BCLC Stage C Adult Hepatocellular Carcinoma; BCLC Stage D Adult Hepatocellular Carcinoma; Hilar Cholangiocarcinoma; Localized Non-Resectable Adult Liver Carcinoma; Recurrent Adult Liver Carcinoma; Recurrent Childhood Liver Cancer; Recurrent Extrahepatic Bile Duct Carcinoma; Recurrent Gallbladder Carcinoma; Stage II Gallbladder Cancer; Stage III Childhood Hepatocellular Carcinoma; Stage IIIA Gallbladder Cancer; Stage IIIB Gallbladder Cancer; Stage IV Childhood Hepatocellular Carcinoma; Stage IV Distal Bile Duct Cancer; Stage IVA Gallbladder Cancer; Stage IVB Gallbladder Cancer; Unresectable Extrahepatic Bile Duct Carcinoma

Subsurface damage and microstructure development in precision microground hard ceramics using magnetorheological finishing spots.

PubMed

Shafrir, Shai N; Lambropoulos, John C; Jacobs, Stephen D

2007-08-01

We demonstrate the use of spots taken with magnetorheological finishing (MRF) for estimating subsurface damage (SSD) depth from deterministic microgrinding for three hard ceramics: aluminum oxynitride (Al(23)O(27)N(5)/ALON), polycrystalline alumina (Al(2)O(3)/PCA), and chemical vapor deposited (CVD) silicon carbide (Si(4)C/SiC). Using various microscopy techniques to characterize the surfaces, we find that the evolution of surface microroughness with the amount of material removed shows two stages. In the first, the damaged layer and SSD induced by microgrinding are removed, and the surface microroughness reaches a low value. Peak-to-valley (p-v) surface microroughness induced from grinding gives a measure of the SSD depth in the first stage. With the removal of additional material, a second stage develops, wherein the interaction of MRF and the material's microstructure is revealed. We study the development of this texture for these hard ceramics with the use of power spectral density to characterize surface features.

Subsurface Damage and Microstructure Development in Precision Microground Hard Ceramics Using Magnetorheological Finishing Spots

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

Shafrir, S.N.; Lambropoulos, J.C.; Jacobs, S.D.

2007-08-01

We demonstrate the use of spots taken with magnetorheological finishing (MRF) for estimating subsurface damage (SSD) depth from deterministic microgrinding for three hard ceramics: aluminum oxynitride (Al23O27N5/ALON), polycrystalline alumina (AL2O3/PCA), and chemical vapor deposited (CVD) silicon carbide (Si4C/SiC). Using various microscopy techniques to characterize the surfaces, we find that the evolution of surface microroughness with the amount of material removed shows two stages. In the first, the damaged layer and SSD induced by microgrinding are removed, and the surface roughness reaches a low value. Peak-to-valley (p-v) surface microroughness induced from grinding gives a measure of the SSD depth in themore » first stage. With the removal of additional material, a second stage develops, wherein the interaction of MRF and the material's microstructure is revealed. We study the development of this texture for these har ceramics with the use of power spectral density to characterize surface features.« less

Chromium (Ⅵ) removal from aqueous solutions through powdered activated carbon countercurrent two-stage adsorption.

PubMed

Wang, Wenqiang

2018-01-01

To exploit the adsorption capacity of commercial powdered activated carbon (PAC) and to improve the efficiency of Cr(VI) removal from aqueous solutions, the adsorption of Cr(VI) by commercial PAC and the countercurrent two-stage adsorption (CTA) process was investigated. Different adsorption kinetics models and isotherms were compared, and the pseudo-second-order model and the Langmuir and Freundlich models fit the experimental data well. The Cr(VI) removal efficiency was >80% and was improved by 37% through the CTA process compared with the conventional single-stage adsorption process when the initial Cr(VI) concentration was 50 mg/L with a PAC dose of 1.250 g/L and a pH of 3. A calculation method for calculating the effluent Cr(VI) concentration and the PAC dose was developed for the CTA process, and the validity of the method was confirmed by a deviation of <5%. Copyright © 2017. Published by Elsevier Ltd.

Moisture effects on greenhouse gases generation in nitrifying gas-phase compost biofilters.

PubMed

Maia, Guilherme D N; Day, George B; Gates, Richard S; Taraba, Joseph L; Coyne, Mark S

2012-06-01

Gas-phase compost biofilters are extensively used in concentrated animal feeding operations to remove odors and, in some cases, ammonia from air sources. The expected biochemical pathway for these predominantly aerobic systems is nitrification. However, non-uniform media with low oxygen levels can shift biofilter microbial pathways to denitrification, a source of greenhouse gases. Several factors contribute to the formation of anoxic/anaerobic zones: media aging, media and particle structure, air velocity distribution, compaction, biofilm thickness, and moisture content (MC) distribution. The present work studies the effects of media moisture conditions on ammonia (NH(3)) removal and greenhouse gas generation (nitrous oxide, N(2)O and methane, CH(4)) for gas-phase compost biofilters subject to a 100-day controlled drying process. Continuous recordings were made for the three gases and water vapor (2.21-h sampling cycle, each cycle consisted of three gas species, and water vapor, for a total of 10,050 data points). Media moisture conditions were classified into three corresponding media drying rate (DR) stages: Constant DR (wetter media), falling DR, and stable-dry system. The first-half of the constant DR period (0-750 h; MC=65-52%, w.b.) facilitated high NH(3) removal rates, but higher N(2)O generation and no CH(4) generation. At the drier stages of the constant DR (750-950 h; MC=52-48%, w.b.) NH(3) removal remained high but N(2)O net generation decreased to near zero. In the falling DR stage (1200-1480 h; MC=44-13%) N(2)O generation decreased, CH(4) increased, and NH(3) was no longer removed. No ammonia removal or greenhouse gas generation was observed in the stable-dry system (1500-2500 h; MC=13%). These results indicate that media should remain toward the drier region of the constant DR (in close proximity to the falling DR stage; MC=50%, approx.), to maintain high levels of NH(3) removal, reduced levels of N(2)O generation, and nullify levels of CH(4) generation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Gd, I-doped TiO2 thin films coated on solid waste material: synthesis, characterization, and photocatalytic activity under UV or visible light irradiation

NASA Astrophysics Data System (ADS)

Deng, Siwei; Yu, Jiang; Yang, Chun; Chang, Jiahua; Wang, Yizheng; Wang, Ping; Xie, Shiqian

2017-10-01

In this work, titanium dioxide thin films doped with different concentrations of gadolinium (Gd) and iodine (I) were synthesized using the sol-gel method and successfully coated on solid waste material (made in our lab) by dipping, resulting in the titanium dioxide thin-film-coated material (TiO2M). Then, the doped titanium dioxide thin films were characterized by X-ray diffraction (XRD), SEM, and UV-Vis spectroscopy; the optimum coating cycle was evaluated by removal rates of COD and ammonia nitrogen in raw wastewater and secondary effluent. Moreover, the photocatalytic activity was determined by degradation efficiency of methyl orange. The results showed that TiO2M had desirable reusability and the photocatalytic activity was attractive under ultraviolet light irradiation. Furthermore, it is found that the amount of dopant in TiO2 was a key parameter in increasing the photoactivity. 1% Gd-doped TiO2M exhibited the best photocatalytic activity for the degradation of methyl orange with the removal rate reaching 85.55%. The result was in good agreement with the observed smaller crystallite size and profitable crystal structure (anatase phase). Besides, the TiO2M (0.8% Gd-doped TiO2M, 1% Gd-doped TiO2M, 10% I-doped TiO2M, and 5% I-1% Gd-doped TiO2M) with desirable photocatalytic activity at ultraviolet light irradiation was selected for the visible light photocatalytic experiments with taking methyl orange as the target pollutants. The results showed that all of them exhibited the similar photocatalytic activity after 7 h of sunlight irradiation (around 90% removal effect). In general, this research developed a very effective and environmentally friendly photocatalyst for pollutant degradation.

Image-Guided Hypofractionated Radiation Therapy With Stereotactic Body Radiation Therapy Boost and Combination Chemotherapy in Treating Patients With Stage II-III Non-Small Cell Lung Cancer That Cannot Be Removed By Surgery

ClinicalTrials.gov

2017-06-12

Adenocarcinoma of the Lung; Adenosquamous Cell Lung Cancer; Large Cell Lung Cancer; Recurrent Non-small Cell Lung Cancer; Squamous Cell Lung Cancer; Stage IIA Non-small Cell Lung Cancer; Stage IIB Non-small Cell Lung Cancer; Stage IIIA Non-small Cell Lung Cancer; Stage IIIB Non-small Cell Lung Cancer

Entinostat, Nivolumab, and Ipilimumab in Treating Patients With Solid Tumors That Are Metastatic or Cannot Be Removed by Surgery or Locally Advanced or Metastatic HER2-Negative Breast Cancer

ClinicalTrials.gov

2018-03-22

Breast Adenocarcinoma; HER2/Neu Negative; Invasive Breast Carcinoma; Metastatic Malignant Solid Neoplasm; Stage III Breast Cancer AJCC v7; Stage IIIA Breast Cancer AJCC v7; Stage IIIB Breast Cancer AJCC v7; Stage IIIC Breast Cancer AJCC v7; Stage IV Breast Cancer AJCC v6 and v7; Unresectable Solid Neoplasm

Impact of temperature on nitrification in biological activated carbon (BAC) filters used for drinking water treatment.

PubMed

Andersson, A; Laurent, P; Kihn, A; Prévost, M; Servais, P

2001-08-01

The impact of temperature on nitrification in biological granular activated carbon (GAC) filters was evaluated in order to improve the understanding of the nitrification process in drinking water treatment. The study was conducted in a northern climate where very cold water temperatures (below 2 degrees C) prevail for extended periods and rapid shifts of temperature are frequent in the spring and fall. Ammonia removals were monitored and the fixed nitrifying biomass was measured using a method of potential nitrifying activity. The impact of temperature was evaluated on two different filter media: an opened superstructure wood-based activated carbon and a closed superstructure activated carbon-based on bituminous coal. The study was conducted at two levels: pilot scale (first-stage filters) and full-scale (second-stage filters) and the results indicate a strong temperature impact on nitrification activity. Ammonia removal capacities ranged from 40 to 90% in pilot filters, at temperatures above 10 degrees C, while more than 90% ammonia was removed in the full-scale filters for the same temperature range. At moderate temperatures (4-10 degrees C), the first stage pilot filters removed 10-40% of incoming ammonia for both media (opened and closed superstructure). In the full-scale filters, a difference between the two media in nitrification performances was observed at moderate temperatures: the ammonia removal rate in the opened superstructure support (more than 90%) was higher than in the closed superstructure support (45%). At low temperatures (below 4 degrees C) both media performed poorly. Ammonia removal capacities were below 30% in both pilot- and full-scale filters.

Auxin-Regulated Polypeptide Changes at Different Stages of Strawberry Fruit Development 1

PubMed Central

Veluthambi, K.; Poovaiah, B. W.

1984-01-01

The pattern of polypeptides at different stages of strawberry (Fragaria ananassa Duch. cv Ozark Beauty) fruit development was studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. An 81,000-dalton polypeptide appeared between 5 and 10 days after pollination. Polypeptides with molecular weights of 76,000 and 37,000 daltons were formed after 10 days. The control exerted by auxin in the stage-specific formation of polypeptides was investigated by stopping fruit growth after removing the achenes and reinitiating fruit growth by the application of a synthetic auxin, α-naphthaleneacetic acid (NAA). When the achenes were removed from the 5- and 10-day-old fruits, the fruits failed to grow, the 81,000 dalton polypeptide was not formed between 5 and 10 days, and the 76,000- and 37,000-dalton polypeptides were not formed between 10 and 20 days. Application of NAA to fruits deprived of auxin by removal of achenes resulted in the resumption of growth and also in the appearance of these polypeptides. Removal of achenes of the 5- or 10-day-old fruits and growing them without auxin resulted in the formation of 52,000- and 57,000-dalton polypeptides. These two polypeptides were not formed when NAA was applied to fruits after removal of achenes. Supply of NAA to auxin-deprived fruits 5 days after removal of achenes resulted in resumption of growth and also in the disappearance of these two polypeptides, pointing out their possible relation to the inhibition of fruit growth. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:16663624

Reducing false positives of microcalcification detection systems by removal of breast arterial calcifications

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

Mordang, Jan-Jurre, E-mail: Jan-Jurre.Mordang@radboudumc.nl; Gubern-Mérida, Albert; Karssemeijer, Nico

Purpose: In the past decades, computer-aided detection (CADe) systems have been developed to aid screening radiologists in the detection of malignant microcalcifications. These systems are useful to avoid perceptual oversights and can increase the radiologists’ detection rate. However, due to the high number of false positives marked by these CADe systems, they are not yet suitable as an independent reader. Breast arterial calcifications (BACs) are one of the most frequent false positives marked by CADe systems. In this study, a method is proposed for the elimination of BACs as positive findings. Removal of these false positives will increase the performancemore » of the CADe system in finding malignant microcalcifications. Methods: A multistage method is proposed for the removal of BAC findings. The first stage consists of a microcalcification candidate selection, segmentation and grouping of the microcalcifications, and classification to remove obvious false positives. In the second stage, a case-based selection is applied where cases are selected which contain BACs. In the final stage, BACs are removed from the selected cases. The BACs removal stage consists of a GentleBoost classifier trained on microcalcification features describing their shape, topology, and texture. Additionally, novel features are introduced to discriminate BACs from other positive findings. Results: The CADe system was evaluated with and without BACs removal. Here, both systems were applied on a validation set containing 1088 cases of which 95 cases contained malignant microcalcifications. After bootstrapping, free-response receiver operating characteristics and receiver operating characteristics analyses were carried out. Performance between the two systems was compared at 0.98 and 0.95 specificity. At a specificity of 0.98, the sensitivity increased from 37% to 52% and the sensitivity increased from 62% up to 76% at a specificity of 0.95. Partial areas under the curve in the specificity range of 0.8–1.0 were significantly different between the system without BACs removal and the system with BACs removal, 0.129 ± 0.009 versus 0.144 ± 0.008 (p<0.05), respectively. Additionally, the sensitivity at one false positive per 50 cases and one false positive per 25 cases increased as well, 37% versus 51% (p<0.05) and 58% versus 67% (p<0.05) sensitivity, respectively. Additionally, the CADe system with BACs removal reduces the number of false positives per case by 29% on average. The same sensitivity at one false positive per 50 cases in the CADe system without BACs removal can be achieved at one false positive per 80 cases in the CADe system with BACs removal. Conclusions: By using dedicated algorithms to detect and remove breast arterial calcifications, the performance of CADe systems can be improved, in particular, at false positive rates representative for operating points used in screening.« less

Ozone: Stage Two Vapor Recovery Rule and Guidance

EPA Pesticide Factsheets

This page includes the guidance document, fact sheet, memorandum, and final rule on removing Stage II Gasoline Vapor Control Programs from State Implementation Plans (SIP) for the Ozone National Ambient Air Quality Standards (NAAQS)

78 FR 48339 - Airworthiness Directives; Rolls-Royce Corporation Turbofan Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-08

... currently requires removing certain high-pressure turbine (HPT) stage 2 wheels, or performing inspections on... turbofan engines: (1) With an installed high-pressure turbine (HPT) stage 2 wheel, part number (P/N...

Erlotinib Hydrochloride in Treating Patients With Stage IB-IIIA Non-small Cell Lung Cancer That Has Been Completely Removed by Surgery (An ALCHEMIST Treatment Trial)

ClinicalTrials.gov

2018-06-29

ALK Gene Rearrangement; EGFR Exon 19 Deletion Mutation; EGFR NP_005219.2:p.L858R; Stage IB Non-Small Cell Lung Carcinoma AJCC v7; Stage II Non-Small Cell Lung Cancer AJCC v7; Stage IIA Non-Small Cell Lung Carcinoma AJCC v7; Stage IIB Non-Small Cell Lung Carcinoma AJCC v7; Stage IIIA Non-Small Cell Lung Cancer AJCC v7

Talazoparib in Treating Patients With Advanced or Metastatic Solid Tumors That Cannot Be Removed by Surgery and Liver or Kidney Dysfunction

ClinicalTrials.gov

2017-04-20

Estrogen Receptor Negative; Head and Neck Squamous Cell Carcinoma; HER2/Neu Negative; Hormone-Resistant Prostate Cancer; Metastatic Pancreatic Adenocarcinoma; Progesterone Receptor Negative; Solid Neoplasm; Stage III Mesothelioma; Stage IIIA Gastric Cancer; Stage IIIA Non-Small Cell Lung Cancer; Stage IIIA Ovarian Cancer; Stage IIIA Small Cell Lung Carcinoma; Stage IIIB Gastric Cancer; Stage IIIB Non-Small Cell Lung Cancer; Stage IIIB Ovarian Cancer; Stage IIIB Small Cell Lung Carcinoma; Stage IIIC Gastric Cancer; Stage IIIC Ovarian Cancer; Stage IV Mesothelioma; Stage IV Non-Small Cell Lung Cancer; Stage IV Ovarian Cancer; Stage IV Small Cell Lung Carcinoma; Triple-Negative Breast Carcinoma

Performance evaluation of an anaerobic/aerobic landfill-based digester using yard waste for energy and compost production

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

Yazdani, Ramin, E-mail: ryazdani@sbcglobal.net; Civil and Environmental Engineering, University of California, One Shields Avenue, Ghausi Hall, Davis, CA 95616; Barlaz, Morton A., E-mail: barlaz@eos.ncsu.edu

2012-05-15

Highlights: Black-Right-Pointing-Pointer Biochemical methane potential decreased by 83% during the two-stage operation. Black-Right-Pointing-Pointer Net energy produced was 84.3 MWh or 46 kWh per million metric tons (Mg). Black-Right-Pointing-Pointer The average removal efficiency of volatile organic compounds (VOCs) was 96-99%. Black-Right-Pointing-Pointer The average removal efficiency of non-methane organic compounds (NMOCs) was 68-99%. Black-Right-Pointing-Pointer The two-stage batch digester proved to be simple to operate and cost-effective. - Abstract: The objective of this study was to evaluate a new alternative for yard waste management by constructing, operating and monitoring a landfill-based two-stage batch digester (anaerobic/aerobic) with the recovery of energy and compost. Themore » system was initially operated under anaerobic conditions for 366 days, after which the yard waste was aerated for an additional 191 days. Off gas generated from the aerobic stage was treated by biofilters. Net energy recovery was 84.3 MWh, or 46 kWh per million metric tons of wet waste (as received), and the biochemical methane potential of the treated waste decreased by 83% during the two-stage operation. The average removal efficiencies of volatile organic compounds and non-methane organic compounds in the biofilters were 96-99% and 68-99%, respectively.« less

Securing stent during multi-stage laryngotracheoplasty--an evolved technique.

PubMed

Siegel, Bianca; Bent, John P

2015-09-01

Multi-stage laryngotracheoplasty (LTP) typically requires a stent be secured to the airway for 2-6 weeks. Our technique has evolved over time to securing the stent to the strap muscles and tying a series of knots long enough to leave the suture tail protruding through the skin incision, which simplifies stent removal. Retrospective chart review. Twenty-four patients underwent multi-stage LTP at our institution from 2007 to 2013. Eight patients were excluded from the study because they either did not have a stent placed (n=4), or they had a t-tube placed which was not sutured in place (n=4). Of the remaining 16 patients, 62.5% (n=10) had their stent secured via sutures which were buried below the skin, and 37.5% (n=6) via a long suture tail which was left protruding through the end of the skin incision. An incision was required for stent removal 100% of buried sutures patients, and 33% of exposed suture patients (p=0.0009). Average operative time for stent removal was 60min in the buried sutures group, and 25min in the exposed sutures group (p=0.0075). Securing stents via an exposed suture technique decreases the need for making a skin incision during the second stage of the operation, and significantly decreases the operative time of the second stage. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Safety assessment of nanoparamagnetic contrast agents with different coatings for molecular MRI

NASA Astrophysics Data System (ADS)

Azizian, Gholamreza; Riyahi-Alam, Nader; Haghgoo, Soheila; Saffari, Mojtaba; Zohdiaghdam, Reza; Gorji, Ensieh

2013-04-01

Despite the wide application of gadolinium as a contrast agent for magnetic resonance imaging (MRI), there is a serious lack of information on its toxicity. Gadolinium and gadolinium oxide (Gd-oxide) are used as contrast agents for magnetic resonance imaging (MRI). There are methods for reducing toxicity of these materials, such as core nanoparticles coating or conjugating. Therefore, for toxicity evaluation, we compared the viability of commercial contrast agents in MRI (Gd-DTPA) and three nanoparticles with the same core Gd2O3 and small particulate gadolinium oxide or SPGO (< 40 nm) but different coatings of diethyleneglycol (DEG) as Gd2O3-DEG and methoxy polyethylene glycol-silane (mPEG-silane: 550 and 2000 Dalton) as SPGO-mPEG-silane550 and SPGO-mPEG-silane2000, respectively, in the SK-MEL3 cell line, by light microscopy, MTT assay using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide, and the LDH assay detecting lactate dehydrogenase activity. The viability values were not statistically different between the three nanoparticles and Gd-DTPA. The MTT and LDH assay results showed that Gd2O3-DEG nanoparticles were more toxic than Gd-DTPA and other nanoparticles. Also, SPGO-mPEG-silane2000 was more biocompatible than other nanoparticles. The obtained results did not show any significant increase in cytotoxicity of the nanoparticles and Gd-DTPA, neither dose-dependent nor time-dependent. Therefore, DEG and PEG, due to their considerable properties and irregular sizes (different molecular weights), were selected as the useful surface covering materials of nanomagnetic particles that could reveal noticeable relaxivity and biocompatibility characteristics.

A novel cryogenic magnetic refrigerant metal-organic framework based on 1D gadolinium(III) chain

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

Tang, Qun; Li, Peng-Fei; Zou, Zhi-Ming, E-mail: 2014005@glut.edu.cn

2017-02-15

A metal-organic framework (MOF) based on gadolinium ion (Gd{sup 3+}) and tricarboxylate ligand, [Gd(BTPCA)(H{sub 2}O)]·2DMF·3H{sub 2}O (Gd-BTPCA) (H{sub 3}BTPCA =1,1′,1′-(benzene-1,3,5-triyl)tripiperidine-4-carboxylic acid; DMF=dimethylformamide), was synthesized and structurally characterized. The adjacent Gd{sup 3+} ions are intraconnected by the carboxylate groups of the BTPCA{sup 3-} ligands to form a 1D Gd{sup 3+} ion chain. The 1D Gd{sup 3+} ion chains are interconnected by the BTPCA{sup 3-} ligands, giving rise to a 3D framework with 1D open channel. The magnetic studies indicate that Gd-BTPCA exhibits weak ferromagnetic interactions, and acts as a cryogenic magnetic refrigerant having the magnetic entropy change (−ΔS{sub m}) of 20.40more » J kg{sup −1} K{sup −1} for ΔH =7 T at 3 K. - Graphical abstract: A 1D gadolinium(III) chains-based metal-organic framework performed ferromagnetic coupling on the magnetic property. Magnetic investigation reveals that Gd-BTPCA exhibits the entropy change (−ΔS{sub m}) of 20.40 J kg{sup −1} K{sup −1} for ΔH =7 T at 3 K. - Highlights: • The MOF based on gadolinium ion and tricarboxylate ligand was synthesized. • This MOF is connected with 1D Gd{sup 3+} ions chain and the carboxylate groups of BTPCA{sup 3-} ligands. • The magnetic studies indicate that the MOF exhibits the weak ferromagnetic interactions. • Magnetic investigation reveals that the MOF exhibits the high entropy change.« less

Revised Recommendations of the Consortium of MS Centers Task Force for a Standardized MRI Protocol and Clinical Guidelines for the Diagnosis and Follow-Up of Multiple Sclerosis

PubMed Central

Traboulsee, A.; Simon, J.H.; Stone, L.; Fisher, E.; Jones, D.E.; Malhotra, A.; Newsome, S.D.; Oh, J.; Reich, D.S.; Richert, N.; Rammohan, K.; Khan, O.; Radue, E.-W.; Ford, C.; Halper, J.; Li, D.

2016-01-01

SUMMARY An international group of neurologists and radiologists developed revised guidelines for standardized brain and spinal cord MR imaging for the diagnosis and follow-up of MS. A brain MR imaging with gadolinium is recommended for the diagnosis of MS. A spinal cord MR imaging is recommended if the brain MR imaging is nondiagnostic or if the presenting symptoms are at the level of the spinal cord. A follow-up brain MR imaging with gadolinium is recommended to demonstrate dissemination in time and ongoing clinically silent disease activity while on treatment, to evaluate unexpected clinical worsening, to re-assess the original diagnosis, and as a new baseline before starting or modifying therapy. A routine brain MR imaging should be considered every 6 months to 2 years for all patients with relapsing MS. The brain MR imaging protocol includes 3D T1-weighted, 3D T2-FLAIR, 3D T2-weighted, post-single-dose gadolinium-enhanced T1-weighted sequences, and a DWI sequence. The progressive multifocal leukoencephalopathy surveillance protocol includes FLAIR and DWI sequences only. The spinal cord MR imaging protocol includes sagittal T1-weighted and proton attenuation, STIR or phase-sensitive inversion recovery, axial T2- or T2*-weighted imaging through suspicious lesions, and, in some cases, postcontrast gadolinium-enhanced T1-weighted imaging. The clinical question being addressed should be provided in the requisition for the MR imaging. The radiology report should be descriptive, with results referenced to previous studies. MR imaging studies should be permanently retained and available. The current revision incorporates new clinical information and imaging techniques that have become more available. PMID:26564433

Survey of gadolinium-based contrast agent utilization among the members of the Society for Pediatric Radiology: a Quality and Safety Committee report.

PubMed

Blumfield, Einat; Moore, Michael M; Drake, Mary K; Goodman, Thomas R; Lewis, Kristopher N; Meyer, Laura T; Ngo, Thang D; Sammet, Christina; Stanescu, Arta Luana; Swenson, David W; Slovis, Thomas L; Iyer, Ramesh S

2017-05-01

Gadolinium-based contrast agents (GBCAs) have been used for magnetic resonance (MR) imaging over the last three decades. Recent reports demonstrated gadolinium retention in patients' brains following intravenous administration. Since gadolinium is a highly toxic heavy metal, there is a potential for adverse effects from prolonged retention or deposition, particularly in children. For this reason, the Society (SPR) for Pediatric Radiology Quality and Safety committee conducted a survey to evaluate the current status of GBCAs usage among pediatric radiologists. To assess the usage of GBCAs among SPR members. An online 15-question survey was distributed to SPR members. Survey questions pertained to the type of GBCAs used, protocoling workflow, requirement of renal function or pregnancy tests, and various clinical indications for contrast-enhanced MRI examinations. A total of 163 survey responses were compiled (11.1% of survey invitations), the majority of these from academic institutions in the United States. Ninety-four percent reported that MR studies are always or usually protocoled by pediatric radiologists. The most common GBCA utilized by survey respondents were Eovist (60.7%), Ablavar (45.4%), Gadovist (38.7%), Magnevist (34.4%) and Dotarem (32.5%). For several clinical indications, survey responses regarding GBCA administration were concordant with American College of Radiology (ACR) Appropriateness Criteria, including seizures, headache and osteomyelitis. For other indications, including growth hormone deficiency and suspected vascular ring, survey responses revealed potential overutilization of GBCAs when compared to ACR recommendations. Survey results demonstrate that GBCAs are administered judiciously in children, yet there is an opportunity to improve their utilization with the goal of reducing potential future adverse effects.

Spectral presaturation inversion recovery MR imaging sequence after gadolinium injection to differentiate fibrotic scar tissue and neoplastic strands in the mesorectal fat in patients undergoing restaging of rectal carcinoma after neoadjuvant chemo- and radiation therapy.

PubMed

Quaia, Emilio; Ulcigrai, Veronica; Coss, Matteo; De Paoli, Luca; Ukmar, Maja; Zanconati, Fabrizio; De Pellegrin, Alessandro; De Manzini, Nicolò; Cova, Maria Assunta

2011-11-01

To retrospectively assess the value of spectral presaturation by inversion-recovery (SPIR) magnetic resonance (MR) imaging sequence after gadolinium injection to differentiate fibrotic scar tissue and tumoral infiltration within the mesorectal fat in patients with rectal carcinoma undergoing MR restaging after neoadjuvant chemo- and radiation therapy (CRT). Forty-three consecutive patients (mean age, 65.8 years; range, 46-85 years; male:female, 29:14) with locally advanced rectal carcinoma underwent CRT followed by surgery. MR imaging was performed before and after completion of CRT by using T2-weighted turbo spin-echo and T1-weighted SPIR sequences before and after gadolinium injection, and MR images were assessed by two radiologists in consensus. Logistic regression was conducted to test the significance of the MR image findings with histology. After CRT the disease was either limited to the rectal wall (n = 18 patients) or presented perirectal infiltration (n = 25) on histology. In 21 patients, mesorectal enhancing strands were observed. Reticular-shaped enhancing strands reaching the mesorectal fascia presented the highest correlation with tumor infiltration of the mesorectal fat (OR 130.33, 95% CI: 4.1-4220.29; logistic regression), whereas linear-shaped enhancing strands either reaching or not reaching the mesorectal fascia (OR 0.25 or 0.1, 95% CI: 0.024-2.6 or 0.01-1.07) revealed the lowest correlation. Reticular-shaped enhancing strands on SPIR MR imaging after gadolinium injection are associated with tumor infiltration of the mesorectal fat. Copyright © 2011 AUR. Published by Elsevier Inc. All rights reserved.

Veliparib With or Without Radiation Therapy, Carboplatin, and Paclitaxel in Patients With Stage III Non-small Cell Lung Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-06-01

Large Cell Lung Carcinoma; Lung Adenocarcinoma; Lung Adenocarcinoma, Mixed Subtype; Minimally Invasive Lung Adenocarcinoma; Squamous Cell Lung Carcinoma; Stage III Non-Small Cell Lung Cancer AJCC v7; Stage IIIA Non-Small Cell Lung Cancer AJCC v7; Stage IIIB Non-Small Cell Lung Cancer AJCC v7

Membrane technology for sustainable treated wastewater reuse: agricultural, environmental and hydrological considerations.

PubMed

Oron, Gideon; Gillerman, Leonid; Bick, Amos; Manor, Yossi; Buriakovsky, Nisan; Hagin, Joseph

2008-01-01

Field experiments were conducted in agricultural fields in which secondary wastewater of the City of Arad (Israel) is reused for irrigation. For sustainable agricultural production and safe groundwater recharge the secondary effluent is further polished by a combined two-stage membrane pilot system. The pilot membrane system consists of two main in row stages: Ultrafiltration (UF) and Reverse Osmosis (RO). The UF stage is efficient in the removal of the pathogens and suspended organic matter while the successive RO stage provides safe removal of the dissolved solids (salinity). Effluents of various qualities were applied for agricultural irrigation along with continuous monitoring of the membrane system performance. Best agricultural yields were obtained when applying effluent having minimal content of dissolved solids (after the RO stage) as compared with secondary effluent without any further treatment and extended storage. In regions with shallow groundwater reduced soil salinity in the upper productive layers, maintained by extra membrane treatment, will guarantee minimal dissolved solids migration to the aquifers and minimize salinisation processes. (c) IWA Publishing 2008.

Combination Chemotherapy, Radiation Therapy, and Bevacizumab in Treating Patients With Newly Diagnosed Stage III Non-small Cell Lung Cancer That Cannot Be Removed by Surgery

ClinicalTrials.gov

2018-03-22

Adenosquamous Lung Carcinoma; Large Cell Lung Carcinoma; Lung Adenocarcinoma; Minimally Invasive Lung Adenocarcinoma; Squamous Cell Lung Carcinoma; Stage IIIA Non-Small Cell Lung Cancer AJCC v7; Stage IIIB Non-Small Cell Lung Cancer AJCC v7

Mucoadhesive Oral Wound Rinse in Preventing and Treating Stomatitis in Patients With ER- or PR-Positive Metastatic or Locally Recurrent Breast Cancer That Cannot be Removed by Surgery Receiving Everolimus

ClinicalTrials.gov

2018-04-26

Estrogen Receptor-positive Breast Cancer; HER2-negative Breast Cancer; Oral Complications; Progesterone Receptor-positive Breast Cancer; Recurrent Breast Cancer; Stage IIIB Breast Cancer; Stage IIIC Breast Cancer; Stage IV Breast Cancer

Magnetic resonance imaging in local staging of endometrial carcinoma: diagnostic performance, pitfalls, and literature review.

PubMed

Zandrino, Franco; La Paglia, Ernesto; Musante, Francesco

2010-01-01

To assess the diagnostic accuracy of magnetic resonance imaging in local staging of endometrial carcinoma, and to review the results and pitfalls described in the literature. Thirty women with a histological diagnosis of endometrial carcinoma underwent magnetic resonance imaging. Unenhanced T2-weighted and dynamic contrast-enhanced Ti-weighted sequences were obtained. Hysterectomy and salpingo-oophorectomy was performed in all patients. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for the detection of deep myometrial and cervical infiltration. For deep myometrial infiltration T2-weighted sequences reached a sensitivity of 85%, specificity of 76%, PPV of 73%, NVP of 87%, and accuracy of 80%, while contrast-enhanced scans reached a sensitivity of 90%, specificity of 80%, PPV of 82%, NPV of 89%, and accuracy of 85%. For cervical infiltration T2-weighted sequences reached a sensitivity of 75%, specificity of 88%, PPV of 50%, NPV of 96%, and accuracy of 87%, while contrast-enhanced scans reached a sensitivity of 100%, specificity of 94%, PPV of 75%, NPV of 100%, and accuracy of 95%. Unenhanced and dynamic gadolinium-enhanced magnetic resonance allows accurate assessment of myometrial and cervical infiltration. Information provided by magnetic resonance imaging can define prognosis and management.

Trace elements and heavy metals in hair of stage III breast cancer patients.

PubMed

Benderli Cihan, Yasemin; Sözen, Selim; Oztürk Yıldırım, Sema

2011-12-01

This prospective study was designed to compare the hair levels of 36 elements in 52 patients with stage III breast cancer to those of an equal number of healthy individuals. Principal component and cluster analysis were used for source of identification and apportionment of heavy metals and trace elements in these two groups. A higher average level of iron was found in samples from patients while controls had higher levels of calcium. Both patients and controls had elevated levels of tin, magnesium, zinc, and sodium. Almost all element values in cancer patients showed higher dispersion and asymmetry than in healthy controls. Between the two groups, there were statistically significant differences in the concentrations of silver, arsenic, gold, boron, barium, beryllium, calcium, cadmium, cerium, cobalt, cesium, gadolinium, manganese, nickel, lead, antimony, scandium, selenium, and zinc (p < 0.05). Strong positive correlations were found between lead and gold (r = 0.785) in the cancer group and between palladium and cobalt (r = 0.945) in the healthy individuals. Our results show that there are distinct patterns of heavy metals and trace elements in the hair of breast cancer patients in comparison to healthy controls. These results could be of significance in the diagnosis of breast cancer.

Rectal sac distention is induced by 20-hydroxyecdysone in the pupa of Bombyx mori.

PubMed

Suzuki, Takumi; Sakurai, Sho; Iwami, Masafumi

2009-03-01

Holometabolous insects do not excrete but store metabolic wastes during the pupal period. The waste is called meconium and is purged after adult emergence. Although the contents of meconium are well-studied, the developmental and physiological regulation of meconium accumulation is poorly understood. In Bombyx mori, meconium is accumulated in the rectal sac; thereby, the rectal sac distends at the late pupal stage. Here, we show that rectal sac distention occurs between 4 and 5 days after pupation. The distention is halted by brain-removal just after larval-pupal ecdysis but not by brain-removal 1 day after pupation. In the pupae, brain-removal just after ecdysis kept the hemolymph ecdysteroid titer low during early and mid-pupal stages. An injection of 20-hydroxyecdysone (20E) evoked the distention that was halted by brain-removal in a dose-dependent manner. Therefore, brain-removal caused the lack of ecdysteroid, and rectal sac distention did not appear in the brain-removed pupae because of the lack of ecdysteroid. We conclude that rectal sac distention is one of the developmental events regulated by 20E during the pupal period in B. mori.

Large-scale multi-stage constructed wetlands for secondary effluents treatment in northern China: Carbon dynamics.

PubMed

Wu, Haiming; Fan, Jinlin; Zhang, Jian; Ngo, Huu Hao; Guo, Wenshan

2018-02-01

Multi-stage constructed wetlands (CWs) have been proved to be a cost-effective alternative in the treatment of various wastewaters for improving the treatment performance as compared with the conventional single-stage CWs. However, few long-term full-scale multi-stage CWs have been performed and evaluated for polishing effluents from domestic wastewater treatment plants (WWTP). This study investigated the seasonal and spatial dynamics of carbon and the effects of the key factors (input loading and temperature) in the large-scale seven-stage Wu River CW polishing domestic WWTP effluents in northern China. The results indicated a significant improvement in water quality. Significant seasonal and spatial variations of organics removal were observed in the Wu River CW with a higher COD removal efficiency of 64-66% in summer and fall. Obvious seasonal and spatial variations of CH 4 and CO 2 emissions were also found with the average CH 4 and CO 2 emission rates of 3.78-35.54 mg m -2 d -1 and 610.78-8992.71 mg m -2 d -1 , respectively, while the higher CH 4 and CO 2 emission flux was obtained in spring and summer. Seasonal air temperatures and inflow COD loading rates significantly affected organics removal and CH 4 emission, but they appeared to have a weak influence on CO 2 emission. Overall, this study suggested that large-scale Wu River CW might be a potential source of GHG, but considering the sustainability of the multi-stage CW, the inflow COD loading rate of 1.8-2.0 g m -2 d -1 and temperature of 15-20 °C may be the suitable condition for achieving the higher organics removal efficiency and lower greenhouse gases (GHG) emission in polishing the domestic WWTP effluent. The obtained knowledge of the carbon dynamics in large-scale Wu River CW will be helpful for understanding the carbon cycles, but also can provide useful field experience for the design, operation and management of multi-stage CW treatments. Copyright © 2017 Elsevier Ltd. All rights reserved.

KSC-06pd1694

NASA Image and Video Library

2006-08-01

KENNEDY SPACE CENTER, FLA. - On Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, workers remove the protective covers from the engine nozzle on the second stage segment removed from the Delta II rocket. At the Boeing plant in Alabama, a leak was observed in the second-stage oxidizer tank for another Delta II that had been scheduled to launch in November; therefore, all identical tanks scheduled for launch in the near future are being checked. The second stage for the Delta II that will launch STEREO cannot be effectively tested while atop the first stage at Pad 17-B. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. STEREO is expected to lift off in late August 2006. Photo credit: NASA/Jim Grossmann

ICPS Removal from Shipping Container

NASA Image and Video Library

2017-03-09

Inside the United Launch Alliance (ULA) Horizontal Integration Facility at Cape Canaveral Air Force Station in Florida, a crane lifts the shipping container cover away from the Interim Cryogenic Propulsion Stage (ICPS) for NASA's Space Launch System rocket, followed by the ICPS bring removed and placed on a work stand for processing. The ICPS is the first integrated piece of flight hardware to arrive for the SLS. The ICPS arrived from the ULA facility in Decatur, Alabama. The ICPS is the in-space stage that is located toward the top of the rocket, between the Launch Vehicle Stage Adapter and the Orion Spacecraft Adapter. It will provide some of the in-space propulsion during Orion's first flight test atop the SLS on Exploration Mission 1.

Enhancement of the complete autotrophic nitrogen removal over nitrite process in a modified single-stage subsurface vertical flow constructed wetland: Effect of saturated zone depth.

PubMed

Huang, Menglu; Wang, Zhen; Qi, Ran

2017-06-01

This study was conducted to explore enhancement of the complete autotrophic nitrogen removal over nitrite (CANON) process in a modified single-stage subsurface vertical flow constructed wetland (VSSF) with saturated zone, and nitrogen transformation pathways in the VSSF treating digested swine wastewater were investigated at four different saturated zone depths (SZDs). SZD significantly affected nitrogen transformation pathways in the VSSF throughout the experiment. As the SZD was 45cm, the CANON process was enhanced most effectively in the system owing to the notable enhancement of anammox. Correspondingly, the VSSF had the best TN removal performance [(76.74±7.30)%] and lower N 2 O emission flux [(3.50±0.22)mg·(m 2 ·h) - 1 ]. It could be concluded that autotrophic nitrogen removal via CANON process could become a primary route for nitrogen removal in the VSSF with optimized microenvironment that developed as a result of the appropriate SZD. Copyright © 2017 Elsevier Ltd. All rights reserved.

One-stage surgery for removal of intravascular leiomyomatosis extending to right ventricle.

PubMed

Chiang, Ching-Shu; Chen, Po-Lin; Kuo, Tzu-Ting; Chen, I-Ming; Wu, Nai-Yuan; Chang, Hsiao-Huang

2018-03-01

Intravascular leiomyomatosis (IVL) is a rare nonmalignant tumor that can be fatal if untreated. A 49-year-old nulliparous Asian woman who underwent hysterectomy and left salpingo-oophorectomy for multiple uterine leiomyomas 18 months prior presented complaining of intermittent palpitation and chest tightness for approximately 1 month. Echocardiography revealed a large mobile tumor mass extending from the inferior vena cava (IVC) to the right atrium that partially obstructed IVC flow and tricuspid inflow. Thoracicabdominopelvic computed tomography revealed a left adnexal tumor (4.8 × 2.5 cm) causing intravascular obstruction extending from the left internal iliac vein to the IVC, right atrium, and right ventricle. IVL with right heart involvement INTERVENTIONS:: Under cardiopulmonary bypass, a one-stage surgery combining sternotomy and laparotomy was performed. The tumor was approached and extracted via sternotomy, and tumor detachment and removal of residual tumors was accomplished via laparotomy. A firm, smooth, and regularly shape tumor 15.5 × 5.5 × 2.5 in size was completely removed and histopathologically confirmed as IVL. The patient tolerated the surgical procedure well and no postoperative complication was noted. We describe a one-stage surgical approach to completely remove an IVL extending to the right ventricle.

Enhancements in hepatobiliary imaging: the spectrum of gadolinium-ethoxybenzyl diethylenetriaminepentaacetic acid usages in hepatobiliary magnetic resonance imaging.

PubMed

Channual, Stephanie; Pahwa, Anokh; Lu, David S; Raman, Steven S

2016-09-01

Gadolinium-ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) is a unique hepatocyte-specific contrast agent approved for clinical use in the United States in 2008. Gd-EOB-DTPA-enhanced MR has shown to improve detection and characterization of hepatic lesions. Gd-EOB-DTPA is now being routinely used in daily clinical practice worldwide. Therefore, it is important for radiologists to be familiar with the potential uses and pitfalls of Gd-EOB-DTPA, which extends beyond the assessment of focal hepatic lesions. The purpose of this article is to review the various usages of Gd-EOB-DTPA in hepatobiliary MR imaging.

Composition for radiation shielding

DOEpatents

Kronberg, J.W.

1994-08-02

A composition for use as a radiation shield is disclosed. The shield has a depleted uranium core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container. 2 figs.

Investigation of terbium in the ferroelectric crystal, gadolinium molybdate, as a potential laser

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

Crouch, J.E.

A preliminary non-stimulated study of the laser host combination Gd(2 - x)Tb(x)(MoO4)3 is made. The host material, gadolinium molybdate (GMO), is a ferroelectric/ferroelastic crystal. An investigation of temperature and external electric field affects on the absorption and fluorescence of the crystal did not produce any unusual results. The terbium ion, Tb(3+), peak cross section in GMO for the 5D sub 4 to 7F sub 5 transition is 10 x 10 to the minus twenty first power sq. cm. at 300K. The wavelength of this four level laser transition is 543 nm. (GRA)

Composition for radiation shielding

DOEpatents

Kronberg, James W.

1994-01-01

A composition for use as a radiation shield. The shield has a depleted urum core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container.

MRI with intrathecal MRI gadolinium contrast medium administration: a possible method to assess glymphatic function in human brain.

PubMed

Eide, Per Kristian; Ringstad, Geir

2015-11-01

Recently, the "glymphatic system" of the brain has been discovered in rodents, which is a paravascular, transparenchymal route for clearance of excess brain metabolites and distribution of compounds in the cerebrospinal fluid. It has already been demonstrated that intrathecally administered gadolinium (Gd) contrast medium distributes along this route in rats, but so far not in humans. A 27-year-old woman underwent magnetic resonance imaging (MRI) with intrathecal administration of gadobutrol, which distributed throughout her entire brain after 1 and 4.5 h. MRI with intrathecal Gd may become a tool to study glymphatic function in the human brain.

Gadolinium and didymium (praseodymium/neodymium) cations as capture agents in lightmicroscopical histochemistry of acid and alkaline phosphatase.

PubMed

Halbhuber, K J; Zimmermann, N

1987-01-01

In previous papers, cerium and lanthanum based methods for light-microscopical detection of acid and alkaline phosphatase activity were proposed. In this paper, the usefulness of other lanthanide cations such as gadolinium and praseodymium/neodymium cations as capture agents in phosphatase histochemistry is tested. It is evident that phosphate ions were sufficiently trapped by these cations. According to the lead and silver multistep procedures earlier described it is possible to visualize alkaline phosphatase activity in the brush borders of the intestine or kidney as well as acid phosphatase activity in the lysosomes. These methods can be recommended.

Gadolinium-doped water cerenkov-based neutron and high energy gamma-ray detector and radiation portal monitoring system

DOEpatents

Dazeley, Steven A; Svoboda, Robert C; Bernstein, Adam; Bowden, Nathaniel

2013-02-12

A water Cerenkov-based neutron and high energy gamma ray detector and radiation portal monitoring system using water doped with a Gadolinium (Gd)-based compound as the Cerenkov radiator. An optically opaque enclosure is provided surrounding a detection chamber filled with the Cerenkov radiator, and photomultipliers are optically connected to the detect Cerenkov radiation generated by the Cerenkov radiator from incident high energy gamma rays or gamma rays induced by neutron capture on the Gd of incident neutrons from a fission source. The PMT signals are then used to determine time correlations indicative of neutron multiplicity events characteristic of a fission source.

Band-gap modulation via gallium substitution in cerium doped gadolinium aluminum garnet using a mixed fuel combustion approach

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

Tyagi, Mohit; Pitale, Shreyas S.; Ghosh, Manoranjan

2014-04-24

Cerium doped Gadolinium garnets (Gd{sub 3}Al{sub x}Ga{sub 5−x}O{sub 12} where 0≤x≤5) are synthesized via combustion synthesis using mixture of urea and glycine fuels. A 4h Post annealing at 1400 oC is found to be necessary for pure phase formation. Lattice spacing variation as a result of partial or total Ga substitution at Al site was mapped by X-ray diffraction. Photoluminescence emission of Ce shifts as a consequence of Ga substitution and therefore suggests a local re-adjustment of crystal field around activator site.

Lectin conjugates as biospecific contrast agents for MRI. Coupling of Lycopersicon esculentum agglutinin to linear water-soluble DTPA-loaded oligomers.

PubMed

Pashkunova-Martic, Irena; Kremser, Christian; Galanski, Markus; Schluga, Petra; Arion, Vladimir; Debbage, Paul; Jaschke, Werner; Keppler, Bernhard

2011-06-01

Magnetic resonance imaging (MRI) requires synthesis of contrast media bearing targeting groups and numerous gadolinium chelating groups generating high relaxivity. This paper explores the results of linking the gadolinium chelates to the targeting group, a protein molecule, via various types of linkers. Polycondensates of diethylenetriaminepentaacetic acid (DTPA) with either diols or diamines were synthesised and coupled to the targeting group, a lectin (Lycopersicon esculentum agglutinin, tomato lectin) which binds with high affinity to specific oligosaccharide configurations in the endothelial glycocalyx. The polycondensates bear up to four carboxylic groups per constitutive unit. Gd-chelate bonds are created through dative interactions with the unshared pair of electrons on each oxygen and nitrogen atom on DTPA. This is mandatory for complexation of Gd(III) and avoidance of the severe toxicity of free gadolinium ions. The polymer-DTPA compounds were characterised by (1)H NMR and mass spectrometry. The final lectin-DTPA-polycondensate conjugates were purified by fast protein liquid chromatography (FPLC). The capacity for specific binding was assessed, and the MRI properties were examined in order to evaluate the use of these oligomers as components of selective perfusional contrast agents.

Cross-linkable liposomes stabilize a magnetic resonance contrast-enhancing polymeric fastener.

PubMed

Smith, Cartney E; Kong, Hyunjoon

2014-04-08

Liposomes are commonly used to deliver drugs and contrast agents to their target site in a controlled manner. One of the greatest obstacles in the performance of such delivery vehicles is their stability in the presence of serum. Here, we demonstrate a method to stabilize a class of liposomes that load gadolinium, a magnetic resonance (MR) contrast agent, as a model cargo on their surfaces. We hypothesized that the sequential adsorption of a gadolinium-binding chitosan fastener on the liposome surface followed by covalent cross-linking of the lipid bilayer would provide enhanced stability and improved MR signal in the presence of human serum. To investigate this hypothesis, liposomes composed of diyne-containing lipids were assembled and functionalized via chitosan conjugated with a hydrophobic anchor and diethylenetriaminepentaacetic acid (DTPA). This postadsorption cross-linking strategy served to stabilize the thermodynamically favorable association between liposome and polymeric fastener. Furthermore, the chitosan-coated, cross-linked liposomes proved more effective as delivery vehicles of gadolinium than uncross-linked liposomes due to the reduced liposome degradation and chitosan desorption. Overall, this study demonstrates a useful method to stabilize a broad class of particles used for systemic delivery of various molecular payloads.