scholarly journals Are radiopharmaceuticals self-sterilizing? Radiation effect of gallium-68 and lutetium-177 on bacillus pumilus and staphylococcus succinus

2021 ◽  
Vol 60 (06) ◽  
pp. 445-449
Author(s):  
Simon Poetzsch ◽  
Winfried Brenner ◽  
Sarah Spreckelmeyer
Keyword(s):  
Membrane Filtration ◽  
Bacillus Pumilus ◽  
High Energy ◽  
Good Manufacturing Practice ◽  
Positron Energy ◽  
Bacteria Growth ◽  
Intravenous Injections ◽  
Preparation Conditions ◽  
Gallium 68 ◽  
House Production

Abstract Background For radiopharmaceuticals, aseptic preparation in combination with filtration is the most commonly used sterilizing method. In general, the production of radiopharmaceuticals needs to fulfil the requirements of good manufacturing practice. In the scope of this work, we focused on the positron emitter gallium-68 and on the therapeutically used beta- and gamma-emitter lutetium-177, as they are routinely used for in-house synthesis of radiopharmaceuticals in nuclear medicine departments. Our hypothesis is, that radiopharmaceuticals might be self-sterilizing due to a high radioactivity concentration and high-energy radionuclides in the preparation for intravenous injections. Results Incubation with gallium-68 and lutetium-177 for both 30 minutes and 5 hours post-dispensing did not cause any significant effect on bacteria growth. As the theoretical dose is only 0.1–0.6 % of the Ph. Eur. recommended dose of 25 kGy, we conclude that the beta and positron energy of lutetium-177 and gallium-68 as used for standard radiopharmaceutical in-house production is not sufficient to decrease the number of colony forming units compared to the control values. Conclusions Based on these findings, gallium-68 and lutetium-177 labeled radiopharmaceuticals are not self-sterilizing under the tested conditions with respect to bacillus pumilus and staphylococcus succinus. Consequently, strict aseptic preparation conditions in addition to end-sterilization of the radiopharmaceutical e.g. through membrane filtration are strongly advised for in-house productions.

scholarly journals Are radiopharmaceuticals self-sterilizing? Radiation effect of gallium-68 and lutetium-177 on bacillus pumilus and staphylococcus succinus

2020 ◽  
Author(s):  
Simon Poetzsch ◽  
Winfried Brenner ◽  
Sarah Spreckelmeyer
Keyword(s):  
Membrane Filtration ◽  
Bacillus Pumilus ◽  
High Energy ◽  
Good Manufacturing Practice ◽  
Positron Energy ◽  
Bacteria Growth ◽  
Intravenous Injections ◽  
Preparation Conditions ◽  
Colony Forming Units ◽  
Gallium 68

Abstract Background For radiopharmaceuticals, aseptic preparation in combination with filtration is the most chosen sterilizing method. In general, the production of radiopharmaceuticals needs to fulfil the requirements of good manufacturing practice. In the scope of this work, we focused on the positron emitter gallium-68 and on the therapeutically used beta- and gamma-emitter lutetium-177, as they are routinely used for in-house synthesis of radiopharmaceuticals in nuclear medicine departments. Our hypothesis is, that radiopharmaceuticals might be self-sterilizing due to a high radioactivity concentration and high-energy radionuclides in the preparation for intravenous injections. Results Incubation with gallium-68 and lutetium-177 for both 30 minutes and 5 hours post-dispensing did not cause any significant effect on bacteria growth. As the theoretical dose is only 0.1–0.6% of the Ph. Eur. recommended dose of 25 kGy, we conclude that the beta and positron energy of lutetium-177 and gallium-68 as used for standard radiopharmaceutical in-house production is not sufficient to decrease the number of colony forming units compared to the control values. Conclusions Based on these findings, gallium-68 and lutetium-177 labeled radiopharmaceuticals are not self-sterilizing under the tested conditions with respect to bacillus pumilus and staphylococcus succinus. Consequently, strict aseptic preparation conditions in addition to end-sterilization of the radiopharmaceutical e.g. through membrane filtration are strongly advised for in-house productions.

scholarly journals Microstructural Investigation of Nanocrystalline Hydrogen-Storing Mg-Titanate Nanotube Composites Processed by High-Pressure Torsion

Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 563 ◽  
Author(s):  
Marcell Gajdics ◽  
Tony Spassov ◽  
Viktória Kovács Kis ◽  
Ferenc Béke ◽  
Zoltán Novák ◽  
...  
Keyword(s):  
High Pressure ◽  
Ball Milling ◽  
High Pressure Torsion ◽  
High Energy ◽  
Titanate Nanotubes ◽  
Microstructural Investigation ◽  
Microstructural Parameters ◽  
Preparation Conditions ◽  
Average Dislocation Density ◽  
Nanotube Composites

A high-energy ball milling and subsequent high-pressure torsion method was applied to synthesize nanocrystalline magnesium samples catalyzed by TiO2 or titanate nanotubes. The microstructure of the as-milled powders and the torqued bulk disks was characterized by X-ray diffraction. The recorded diffractograms have been evaluated by the convolutional multiple whole profile fitting algorithm, which provided microstructural parameters (average crystal size, crystallite size distribution, average dislocation density). The morphology of the nanotube-containing disks has been examined by high-resolution transmission electron microscopy. The effect of the different additives and preparation conditions on the hydrogen absorption behavior was investigated in a Sieverts’-type apparatus. It was found that the ball-milling route has a prominent effect on the dispersion and morphology of the titanate nanotubes, and the absorption capability of the Mg-based composite is highly dependent on these features.

Cosmic Ray Positron Production by Gamma Ray Interactions on Starlight

1991 ◽  
Vol 9 (1) ◽  
pp. 115-117 ◽  
Author(s):  
A. Mastichiadis ◽  
R. J. Protheroe ◽  
S. A. Stephens
Keyword(s):  
Production Rate ◽  
Unit Volume ◽  
Gamma Ray ◽  
Cosmic Ray ◽  
High Energy ◽  
Local Region ◽  
Positron Energy ◽  
Average Production ◽  
The Galaxy ◽  
Positron Production

AbstractWe examine the production of cosmic ray positrons by photon-photon pair production of high-energy γ-rays on starlight photons. We start by calculating the production rate as a function of positron energy and distance from the Sun resulting from interactions with sunlight. The results are generalized to production on other types of star. We calculate the average production rate per unit volume averaged over the local region of the galaxy, and we estimate the contribution to the observed intensity from this process.

A Study Into the Use of Milliflex Quantum as Rapid Microbial Detection Method for Microorganisms in Pharmaceutical...

2021 ◽  
Author(s):  
Tim Sandle
Keyword(s):  
Membrane Filtration ◽  
Culture Medium ◽  
Good Manufacturing Practice ◽  
Water Systems ◽  
Problem Of Time ◽  
Microbial Detection ◽  
Alternative Approach ◽  
Microbiological Methods ◽  
Quality Control Testing ◽  
Rapid Microbial Detection

Control of pharmaceutical water systems represents an essential part of Good Manufacturing Practice and embedded within this is the quality control testing of water systems for viable microorganisms, and subjecting the data obtained to trend analysis. This has traditionally been achieved by membrane filtration and the use of a culture medium. While such test methodologies can recover a level of the bioburden present, the incubation times are lengthy. To address the problem of time-to-result, rapid microbiological methods offer an alternative approach. One such example is the Milliflex Quantum, which is the focus of this article.

Congruent Evaporation and Epitaxy in Thin Film Laser Ablation Deposition (Lad) of Rare Earth Transition Metal Elements and Compounds

1990 ◽  
Vol 191 ◽  
Author(s):  
J. P. Gavigan ◽  
D. Givord ◽  
A. Lienard ◽  
O. F. K. Mcgrath ◽  
J. P. Rebouillat ◽  
...  
Keyword(s):  
Thin Film ◽  
Rare Earth ◽  
Laser Ablation ◽  
Transition Metal ◽  
High Energy ◽  
Preparation Technique ◽  
Picosecond Pulses ◽  
Preparation Conditions ◽  
Thin Film Preparation ◽  
Diffraction Patterns

ABSTRACTLaser ablation deposition (LAD) is a versatile thin film preparation technique which has been slowly developing for a number of years, and is currently receiving a lot of attention as demand increasingly exploits its advantages over other established techniques. Apart from its simplicity, one of its main advantages is the possibility of congruently evaporating any solid compound target, be it metal or insulator, due to the extremely high energy and instantaneous power densities attainable with pulsed lasers (up to 50 Jcm−2 and 1012 Wcm−2 for picosecond pulses). In this paper, we report on tests for both congruent evaporation in LAD of a number of rare earth - transition metal intermetallic compounds including Nd2 Fe1 3 B, Yzn0.7, Yni3, Y2 Fe15 and Yni5 for different preparation conditions (using a Nd:YAG laser λ = 1064, 532, 355 nm, τ = 35 ps and 20 ns) and on the epitaxial growth of Yni5 and W on monocrystalline sapphire substrates. Optical and electron microscopy were used to examine film morphology while congruent evaporation was confirmed using x-ray microprobe analysis. In-situ RHEED revealed good epitaxy of the films deposited on sapphire, with the hexagonal diffraction patterns obtained for YNis being identical to those of an YNi 5 reference single crystal.

scholarly journals Fabrication of Polytetrafluoroethylene Coated Micron Aluminium with Enhanced Oxidation

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3384
Author(s):  
Benbo Zhao ◽  
Shixiong Sun ◽  
Yunjun Luo ◽  
Yuan Cheng
Keyword(s):  
Energetic Materials ◽  
Energy Conversion Efficiency ◽  
High Energy ◽  
Thermal Activity ◽  
Sintering Process ◽  
Polymer Shell ◽  
Oxidation Activity ◽  
Preparation Conditions ◽  
Micron Size ◽  
Shell Composite

Aluminium (Al) powders of micron size are widely applied to energetic materials as a high energy fuel. However, its energy conversion efficiency is generally low due to low oxidation activity. In this paper, a polytetrafluoroethylene (PTFE) coating layer with both protection and activation action was successfully introduced onto the surface of Al via adsorption and following heat treatment. The preparation conditions were optimized and the thermal activity of this core-shell composite material was studied. The potential enhancement mechanism for Al oxidation was proposed. The results showed that PTFE powders deformed into membrane on the surface of Al after the sintering process. This polymer shell could act as an effective passivation layer protecting internal Al from oxidation during aging. The reduction in metallic Al of Al/PTFE was decreased by 84.7%, more than that in original spherical Al when the aging time is 60 days. Moreover, PTFE could react with Al resulting in a thin AlF3 layer, which could promote the destruction of Al2O3 shell. Thus, PTFE could enhance oxidation activity of micro-Al. The conversion of Al was increased by a factor of 1.8 when heated to 1100 °C. Improved aging-resistant performance and promoted oxidation activity of Al could potentially broaden its application in the field of energetic materials.

scholarly journals [18F]FET-βAG-TOCA: The Design, Evaluation and Clinical Translation of a Fluorinated Octreotide

Cancers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 865 ◽  
Author(s):  
Louis Allott ◽  
Suraiya Dubash ◽  
Eric O. Aboagye
Keyword(s):  
Somatostatin Receptor ◽  
Peptide Receptor Radionuclide Therapy ◽  
Somatostatin Analogues ◽  
Good Manufacturing Practice ◽  
Biological Evaluation ◽  
Clinical Translation ◽  
Prosthetic Group ◽  
Radiolabelled Peptides ◽  
Gallium 68

The success of Lutathera™ ([177Lu]Lu-DOTA-TATE) in the NETTER-1 clinical trial as a peptide receptor radionuclide therapy (PRRT) for somatostatin receptor expressing (SSTR) neuroendocrine tumours (NET) is likely to increase the demand for patient stratification by positron emission tomography (PET). The current gold standard of gallium-68 radiolabelled somatostatin analogues (e.g., [68Ga]Ga-DOTA-TATE) works effectively, but access is constrained by the limited availability and scalability of gallium-68 radiopharmaceutical production. The aim of this review is three-fold: firstly, we discuss the peptide library design, biological evaluation and clinical translation of [18F]fluoroethyltriazole-βAG-TOCA ([18F]FET-βAG-TOCA), our fluorine-18 radiolabelled octreotide; secondly, to exemplify the potential of the 2-[18F]fluoroethylazide prosthetic group and copper-catalysed azide-alkyne cycloaddition (CuAAC) chemistry in accessing good manufacturing practice (GMP) compatible radiopharmaceuticals; thirdly, we aim to illustrate a framework for the translation of similarly radiolabelled peptides, in which in vivo pharmacokinetics drives candidate selection, supported by robust radiochemistry methodology and a route to GMP production. It is hoped that this review will continue to inspire the development and translation of fluorine-18 radiolabelled peptides into clinical studies for the benefit of patients.

scholarly journals Physical properties of sintered alumina doped with different oxides

2018 ◽  
Vol 50 (4) ◽  
pp. 409-419 ◽  
Author(s):  
Suzana Filipovic ◽  
Nina Obradovic ◽  
Smilja Markovic ◽  
Antonije Djordjevic ◽  
Igor Balac ◽  
...  
Keyword(s):  
Mechanical Activation ◽  
Transition Metal Oxides ◽  
High Energy ◽  
Powder Mixtures ◽  
Preparation Conditions ◽  
Final Density ◽  
Mechanical Measurements ◽  
Optimal Values ◽  
Electrical Permittivity ◽  
Consolidation Parameters

Corundum (?-alumina) is a suiTab. material for usage in various industry fields owing to its chemical stability, electrical and mechanical features. It is known that properties of ceramics could be modified by addition of different oxides, as well as by changing the consolidation parameters. In this respect, alumina was doped with 1 wt.% of Cr2O3, Mn2O3 and NiO, followed by 1 hour of mechanical activation in a high-energy planetary ball mill. A sensitive dilatometer was used for sintering of powder mixtures up to 1400 oC and recording the obtained dilatation. The final density varied between cca. 1.9 and 3.3 g/cm3. Microstructural changes were detected by SEM measurements. Changes in electrical permittivity and loss tangent were associated with the preparation conditions (types of additives, duration of mechanical activation). For a given mixture, the sintering increases the relative permittivity and decreases losses, exhibiting the optimal values of 8.32 and 0.027, respectively, for the sample activated 60 minutes and sintered, with the addition of MnO2. Mechanical measurements indicate significant differences in strength with the addition of different transition metal oxides. Samples with Mn and Ni, activated and sintered, with strength of 121 and 86 MPa, respectively, have a significantly higher tensile strength than the other tested samples, due to their more compact microstructures.

scholarly journals The CALorimetric Electron Telescope (CALET) on the International Space Station: Results from the First Two Years of Operation

2019 ◽  
Vol 208 ◽  
pp. 13001
Author(s):  
Y Asaoka ◽  
O Adriani ◽  
Y Akaike ◽  
K Asano ◽  
MG Bagliesi ◽  
...  
Keyword(s):  
International Space Station ◽  
Gamma Ray ◽  
Space Station ◽  
Cosmic Ray ◽  
The United States ◽  
High Energy ◽  
Positron Energy ◽  
International Space ◽  
Long Term Observation ◽  
Tev Gamma Rays

The CALorimetric Electron Telescope (CALET) space experiment, which has been developed by Japan in collaboration with Italy and the United States, is a high-energy astroparticle physics mission on the International Space Station (ISS). The primary goals of the CALET mission include investigation of possible nearby sources of high-energy electrons, detailed study of galactic cosmic-ray acceleration and propagation, and search for dark matter signatures. With a long-term observation onboard the ISS, the CALET experiment measures the flux of cosmic-ray electrons (including positrons) up to 20 TeV, gamma-rays to 10 TeV, and nuclei up to 1,000 TeV based on its charge separation capability from Z = 1 to 40. Since the start of science operation in mid-October, 2015, a continuous observation has been maintained without any major interruptions. The number of triggered events over 10 GeV is nearly 20 million per month. By using the data obtained during the first two-years, here we present a summary of the CALET observations: 1) Electron+positron energy spectrum, 2) Nuclei analysis, 3) Gamma-ray observation with a characterization of the on-orbit performance. The search results for the electromagnetic counterparts of LIGO/Virgo gravitational wave events are also discussed.

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