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Benchtop nuclear magnetic resonance performance evaluation according to ASTM E691-22 on a population of instruments: Molar substitution determination in hydroxypropyl betadex as a case study for use in quality control environments. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:222-235. [PMID: 37021658 DOI: 10.1002/mrc.5351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/15/2023] [Accepted: 03/31/2023] [Indexed: 06/19/2023]
Abstract
The inclusion of quantitative nuclear magnetic resonance (qNMR) spectroscopy in industry has historically been stifled by a lack of accessibility, caused in-part by the large costs of traditional high-field spectrometers, the maintenance required for these, and the expertise necessary to manage and use them. In recent years, the emergence of benchtop NMR technology, an accessible, affordable, and automatable alternative, has led to a more feasible incorporation of NMR into quality control spaces, an area traditionally reserved for other techniques such as gas chromatography and liquid chromatography, which are routinely combined with detection techniques such as mass spectrometry. While these techniques are commonly used in analyzer-type applications using gold standard methods of analysis, wherein an instrument is dedicated to performing specific assays, this remains uncommon for NMR. Herein, we perform a full method verification using benchtop qNMR on a population of benchtop NMR instruments according to the ASTM designation E691-22, a standard used to determine the precision of a test method. To our knowledge, this is the first published example of this type of study for benchtop NMR spectroscopy. For this work, a total of five analysts performed assays on 23 different benchtop NMR instruments for the analysis of hydroxypropyl betadex according to the USP-NF method, and the results are compared using a variety of statistical methods. The results of this work demonstrate that benchtop NMR technology is effective and robust under repeatability and reproducibility conditions and is a powerful tool for these types of routine quality control analyses.
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Proceedings of the 2023 Viral Clearance Symposium, Session 5: Viral Clearance Strategy and Process Understanding. PDA J Pharm Sci Technol 2024; 78:176-186. [PMID: 38609147 DOI: 10.5731/pdajpst.2024.002245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
Session 5 of the 2023 Viral Clearance Symposium reviewed the strategy and process understanding of viral clearance testing. Topics included learnings from the past, leveraging surrogate-based methodologies, cleaning agents that inactivate enveloped baculoviruses, segregation, and retrovirus-like particles both in continuous process and in-use as spiking viruses. Overall, there were discussions over a wide array of viral clearance determinants.
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Criticism of Workplace Protection Barrier Face Covering Article Mischaracterizes ASTM Standard and its Potential Utility. New Solut 2024; 33:195-197. [PMID: 37933123 DOI: 10.1177/10482911231211319] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
Editor's Note: This is a response to "Why a Workplace Barrier Face Covering is a Bad Idea" by Mark Nicas. DOI: 10.1177/10482911231193771.
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Efficacy of Peracetic Acid and Sodium Hypochlorite against SARS-CoV-2 on Contaminated Surfaces. Appl Environ Microbiol 2023:e0062223. [PMID: 37347194 PMCID: PMC10370308 DOI: 10.1128/aem.00622-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/23/2023] Open
Abstract
SARS-CoV-2 is primarily a respiratory virus that can potentially be transmitted through fomites. Sodium hypochlorite (NaOCl) and peracetic acid (PAA) are widely used disinfectants on surfaces in diverse settings such as hospitals and food production facilities. The objectives of this study were to investigate the virucidal efficacy of NaOCl and PAA against SARS-CoV-2 using the ASTM standard methods. In the suspension assay, NaOCl and PAA (5, 50, and 200 ppm) were tested against SARS-CoV-2 in the presence/absence of soil load after 1 min of contact time. In the carrier assay, NaOCl and PAA were tested at 200, 400, 600, and 1,000 ppm for 1 min and 200 and 1,000 ppm for 5 and 10 min. Stainless steel (SS) and high-density polyethylene (HDPE) disks were used as carriers. The virus was suspended in soil load and the disinfectants were prepared in 300 ppm of hard water. Virus quantification was done by TCID50 assay using Vero-E6 cell line. NaOCl and PAA were effective (> 3 log reduction in infectious virus) at 50 ppm in the absence of soil load. However, in the presence of soil load, 200 ppm was required for > 3 log reduction in virus infectivity. In contrast, NaOCl and PAA at 200 ppm and with a 1-min contact time were not effective against SARS-CoV-2 on either SS or HDPE surfaces. PAA at 200 ppm for 10 min was effective against SARS-CoV-2 on SS and HDPE surfaces, whereas NaOCl required 1,000 ppm for 10 min to be effective against SARS-CoV-2 on both surfaces. IMPORTANCE In the context of the COVID-19 pandemic, the World Health Organization (WHO) recommended the use of chlorine-based products such as sodium hypochlorite (NaOCl) at 1,000 ppm for a minimum of 1 min to disinfect environmental surfaces. However, this recommendation was not based on validated studies on the actual SARS-CoV-2 itself. In fact, over half of the chemical disinfectants, including many peracetic acid products, listed in EPA List N were approved based on "kills a harder-to-kill pathogen" without further validation on SARS-CoV-2. Research on SARS-CoV-2 is restricted to BSL3 laboratories and the urgency of tackling the pandemic might explain the lack of studies on the actual virus. Our results show that the WHO recommendation of 1 min contact time with 1,000 ppm NaOCl is not effective against SARS-CoV-2 on surfaces. Also, our results indicate that PAA is effective against SARS-CoV-2 on surfaces and can be used as safer and more environmentally friendly alternative to NaOCl at a lower concentration.
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Subsidence and fusion performance of a 3D-printed porous interbody cage with stress-optimized body lattice and microporous endplates - a comprehensive mechanical and biological analysis. Spine J 2022; 22:1028-1037. [PMID: 35017054 DOI: 10.1016/j.spinee.2022.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 12/22/2021] [Accepted: 01/03/2022] [Indexed: 02/06/2023]
Abstract
BACKGROUND CONTEXT Cage subsidence remains a serious complication after spinal fusion surgery. Novel porous designs in the cage body or endplate offer attractive options to improve subsidence and osseointegration performance. PURPOSE To elucidate the relative contribution of a porous design in each of the two major domains (body and endplates) to cage stiffness and subsidence performance, using standardized mechanical testing methods, and to analyze the fusion progression via an established ovine interbody fusion model to support the mechanical testing findings. STUDY DESIGN/SETTING A comparative preclinical study using standardized mechanical testing and established animal model. METHODS To isolate the subsidence performance contributed by each porous cage design feature, namely the stress-optimized body lattice (vs. a solid body) and microporous endplates (vs. smooth endplates), four groups of cages (two-by-two combination of these two features) were tested in: (1) static axial compression of the cage (per ASTM F2077) and (2) static subsidence (per ASTM F2267). To evaluate the progression of fusion, titanium cages were created with a microporous endplate and internal lattice architecture analogous to commercial implants used in subsidence testing and implanted in an endplate-sparing, ovine intervertebral body fusion model. RESULTS The cage stiffness was reduced by 16.7% by the porous body lattice, and by 16.6% by the microporous endplates. The porous titanium cage with both porous features showed the lowest stiffness with a value of 40.4±0.3 kN/mm (Mean±SEM) and a block stiffness of 1976.8±27.4 N/mm for subsidence. The body lattice showed no significant impact on the block stiffness (1.4% reduction), while the microporous endplates decreased the block stiffness significantly by 24.9% (p<.0001). All segments implanted with porous titanium cages were deemed rigidly fused by manual palpation, except one at 12 weeks, consistent with robotic ROM testing and radiographic and histologic observations. A reduction in ROM was noted from 12 to 26 weeks (4.1±1.6° to 2.2±1.4° in lateral bending, p<.05; 2.1±0.6° to 1.5±0.3° in axial rotation, p<.05); and 3.3±1.6° to 1.9±1.2° in flexion extension, p=.07). Bone in the available void improved with time in the central aperture (54±35% to 83±13%, p<.05) and porous cage structure (19±26% to 37±21%, p=.15). CONCLUSIONS Body lattice and microporous endplates features can effectively reduce the cage stiffness, therefore reducing the risk of stress shielding and promoting early fusion. While body lattice showed no impact on block stiffness and the microporous endplates reduced the block stiffness, a titanium cage with microporous endplates and internal lattice supported bone ingrowth and segmental mechanical stability as early as 12 weeks in ovine interbody fusion. CLINICAL SIGNIFICANCE Porous titanium cage architecture can offer an attractive solution to increase the available space for bone ingrowth and bridging to support successful spinal fusion while mitigating risks of increased subsidence.
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Enhancement of peripheral seal of medical face masks using a 3-dimensional-printed custom frame. J Am Dent Assoc 2021; 152:542-550. [PMID: 34176568 PMCID: PMC8486490 DOI: 10.1016/j.adaj.2021.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 02/16/2021] [Accepted: 03/05/2021] [Indexed: 01/22/2023]
Abstract
Background During the COVID-19 pandemic, American Society for Testing and Materials level 3 and level 2 medical face masks (MFMs) have been used for most health care workers and even for the first responders owing to a shortage of N95 respirators. However, the MFMs lack effective peripheral seal, leading to concerns about their adequacy to block aerosol exposure for proper protection. The purpose of this study was to evaluate the peripheral seal of level 3 and level 2 MFMs with a 3-dimensional (3D-) printed custom frame. Methods Level 3 and level 2 MFMs were tested on 10 participants with and without a 3D-printed custom frame; the efficiency of mask peripheral seal was determined by means of quantitative fit testing using a PortaCount Fit Tester based on ambient aerosol condensation nuclei counter protocol. Results The 3D-printed custom frame significantly improved the peripheral seal of both level 3 and level 2 MFMs compared with the masks alone (P < .001). In addition, both level 3 and level 2 MFMs with the 3D-printed custom frame met the quantitative fit testing standard specified for N95 respirators. Practical Implications The 3D-printed custom frame over level 3 and level 2 MFMs can offer enhanced peripheral reduction of aerosols when using collapsible masks. With the shortage of N95 respirators, using the 3D-printed custom frame over a level 3 or level 2 MFM is considered a practical alternative to dental professionals.
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Characterization of antimicrobial effect of organotin-based catalysts on diesel-biodiesel deteriogenic microorganisms. ENVIRONMENTAL MONITORING AND ASSESSMENT 2020; 192:802. [PMID: 33263150 DOI: 10.1007/s10661-020-08744-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 11/10/2020] [Indexed: 06/12/2023]
Abstract
Organotin compounds are applied in several industrial reactions and can present antifungal and antibacterial activities. Incorrect handling and storage practices of biodiesel and diesel-biodiesel blends can lead to microbial development, impacting its final quality. Concerning this problem, this work investigated the antimicrobial action of two organotin catalysts used in biodiesel production with four isolated microroorganisms (Bacillus pumilus, Pseudomonas aeruginosa, Pseudallescheria boydii, and Aureobasidium pullulans) and a pool of microorganisms (ASTM E1259 standard practice). Samples of soybean biodiesel with different concentrations of dibutyl tin dilaurate (catalyst 1) and di-n-butyl-oxo-stannane (catalyst 2) were prepared and added of mineral medium. The pool of microorganisms was inoculated and incubated at 30 °C and final biomass was weighted after 14 days. Thereafter, soybean biodiesel with catalyst 2 was used. Fungal biomass was weighted, and plate count was used to assess bacterial growth. Results show that catalysts 1 and 2 presented no inhibitory activity on the pool of microorganisms evaluated. A slight inhibitory activity was observed for B. pumilus and A. pullulans growth, but not for P. boydii, P. aeruginosa, or the pool of microorganisms. All experiment exhibited acidification higher than sterile control. Infrared analysis show less microbiological degradation products in the tin-protected fuel with ASTM inoculum. These results suggest that these tin-based catalysts show no toxic effect on native microbial population and a slight effect on some isolated microbial population in laboratory scale and for the first time shows that these organotin compounds can be employed safely as biodiesel catalyst. Graphical abstract.
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Data-set collected during turning operation of AISI 1045 alloy steel with green cutting fluids in near dry condition. Data Brief 2020; 32:106215. [PMID: 32904360 PMCID: PMC7452595 DOI: 10.1016/j.dib.2020.106215] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/30/2020] [Accepted: 08/18/2020] [Indexed: 11/18/2022] Open
Abstract
This work is to explicate the data collected during the turning of AISI 1045 alloy steel components in near dry condition with emulsified cutting fluids prepared from cooking oils such as Palm oil and Peanut oil. The base oils are tested for its relative density, viscosity and flash point following ASTM standards. Highly influencing turning factors are identified and the experiments are planned and arranged using Taguchi's L27(35) orthogonal array, the experiments are repeated to reduce the errors. The quality aspect of machined components and the machining interface temperature is observed as the outcomes. The prediction models are created for the experiments through regression analysis.
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Infection Control in Dental Anesthesiology: A Time for Preliminary Reconsideration of Current Practices. Anesth Prog 2020; 67:109-120. [PMID: 32633770 PMCID: PMC7342805 DOI: 10.2344/anpr-67-02-12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 04/03/2020] [Indexed: 07/25/2023] Open
Abstract
Relegated to clinical afterthought, the topic of infection control has never taken center stage in our modern dental sedation and anesthesiology practices. Surgical and procedural masks, gloves, gowns, protective eyewear, and appropriate surgical attire have remained de rigueur in both fashion and custom for decades. However, the emergence of certain seminal events throughout health care history has driven mandated changes when practitioners, staff, patients, and the surrounding communities were exposed or put at risk of exposure to infectious disease. Hepatitis, human immunodeficiency virus, and now the global COVID-19 pandemic involving the novel coronavirus SARS-CoV-2, have forced us into rethinking our current practices. This review article will contextualize previous epidemics and their influence on infection control in dental settings, and it will explore the rapid evolution of current modifications to personal protective equipment and infection mitigation practices specific to sedation and anesthesia in dentistry.
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Comparison of ISO and ASTM standards in determining the flexural strength of denture base resin. Eur Oral Res 2019; 53:137-140. [PMID: 31579895 PMCID: PMC6761484 DOI: 10.26650/eor.20190072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 02/14/2019] [Accepted: 03/21/2019] [Indexed: 12/04/2022] Open
Abstract
Purpose: The aim of this study was to compare the differences between the ASTM D790 and
ISO 20795.1.2013 standards in evaluating the flexural strength of heat cure poly
methyl methacrylate (PMMA) denture base resin. Materials and methods: 30 heat cure denture base samples were fabricated in accordance to ISO
20795.1.2013 and ASTM D790 Standards. The specimens were finished and stored
following the standardized protocol. The flexural strength was determined using
universal testing machine at cross head speed of 1.50 mm/min and a span length of
40.00 mm. The mean flexural strength values were calculated in megapascals (MPa),
and statistically analyzed. Results: The mean flexural strength of heat cure PMMA found with ISO and ASTM ranged
between 60.492 MPa and 61.470 MPa. There was no significant difference between
the two methods. Conclusion: The quantitative differences existed in the flexural strength of denture base resin
between ISO 20795.1.2013 and ASTM 790 protocols but those differences had no
statistical and clinical significance.
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Particle analysis of shape factors according to American Society for Testing and Materials. J Biomed Mater Res B Appl Biomater 2019; 108:225-233. [PMID: 30977963 DOI: 10.1002/jbm.b.34382] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 02/12/2019] [Accepted: 03/20/2019] [Indexed: 11/07/2022]
Abstract
Polyethylene wear is one of the major factors influencing the survivorship of joint replacements. Depending on the number, size and morphology of the polyethylene particles, biological responses of the periprosthetic soft tissue in terms of inflammatory processes can occur, leading to loosening of the implant. Various parameters are used to analyze wear particles, which are usually determined by examining scanning electron microscopy (SEM) images with a particle analysis program. In this study, three different software solutions for particle analysis (self-developed Particleanalyzer_HD, Leica QWin and ImageJ) were compared regarding particle number, size and morphology. These solutions were also compared to the American Society for Testing and Materials (ASTM) F1877-16 specifications regarding particle morphology. SEM image analysis revealed no differences for the equivalent circle diameter (p = 0.969). However, a significant difference was found for the aspect ratio between the Particleanalyzer_HD and the other two software solutions (p < 0.001) and between Leica QWin and the other two software solutions regarding the roundness (p < 0.001). Only the Particleanalyzer_HD showed an excellent agreement with the ASTM standard for both morphology parameters (intraclass correlation = 1.000). Only the Particleanalyzer_HD calculated the two morphology parameters according to the ASTM standard. A comparison of the particle morphology between different studies is barely possible, as different algorithms for particle analysis are used. It is strongly recommended that the calculation according to the ASTM standard is used to improve future comparability of findings from wear analysis studies. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:225-233, 2020.
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Conversion of Microbial Lipids to Biodiesel and Basic Lab Tests for Analysis of Fuel-Quality Parameters. Methods Mol Biol 2019; 1995:285-310. [PMID: 31148135 DOI: 10.1007/978-1-4939-9484-7_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
This chapter describes lab-scale procedures for the direct conversion of microbial lipids to fatty acid methyl esters (FAMEs) for use as biodiesel fuel. Methods for the gas chromatography analysis of FAME profiles and equations to predict several fuel-quality parameters are detailed herein. This chapter also provides a complete list summarizing each of the fuel quality tests (e.g., sample size and equipment) that are required by ASTM International D6751 regulations for pure biodiesel fuel (B100) or blend stock. Recommendations for the decolorization of microbial lipid sources containing pigments are also included. This resource should provide a guide to basic conversion and characterization of microbial-derived biodiesel fuels and a roadmap for more-detailed testing required to assess commercial feasibility.
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Data on optimization of production parameters on Persea Americana (Avocado) plant oil biodiesel yield and quality. Data Brief 2018; 20:855-863. [PMID: 30211286 PMCID: PMC6134194 DOI: 10.1016/j.dib.2018.08.064] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 08/09/2018] [Accepted: 08/21/2018] [Indexed: 11/18/2022] Open
Abstract
Biodiesel has continued to receive enormous patronage from world energy demand as a result of its renewable nature, low toxicity, rapid degradation, robust fuel performance and low emission characteristics and its overall environmental friendliness. Hence, these data showed the optimization of temperature, catalyst concentration and type of catalyst, alcohol type and alcohol to oil molar ratio and reaction time on Avocado plant oil biodiesel yield and quality produced via alkali-catalyzed transesterification reaction. Data on the quality of the biodiesel produced by using the American Standard for Testing Materials (ASTM) procedures for biodiesel characterization with different concentrations of alcohol and catalyst under varying temperatures and reaction durations are also provided. The tested biodiesel properties are the cold flow properties (pour point and cloud point) and the critical parameters such as kinematic viscosity at 40 °C, specific gravity at 15 °C, flash point, cetane number, calorific value, iodine value, acid number and sulphated ash percentage.
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Tx/Rx Head Coil Induces Less RF Transmit-Related Heating than Body Coil in Conductive Metallic Objects Outside the Active Area of the Head Coil. Front Neurosci 2017; 11:15. [PMID: 28184184 PMCID: PMC5266708 DOI: 10.3389/fnins.2017.00015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 01/09/2017] [Indexed: 11/25/2022] Open
Abstract
The transmit-receive (Tx/Rx) birdcage head coil is often used for excitation instead of the body coil because of the presumably lower risk of heating in and around conductive implants. However, this common practice has not been systematically tested. To investigate whether the Tx/Rx birdcage head coil produces less heating than the body coil when scanning individuals with implants, we used a 3T clinical scanner and made temperature measurements around a straight 15 cm conductor using either the Tx/Rx body or the head coil for excitation. Additionally, the transmitted fields of a Tx/Rx head coil were measured both in air and in gel using a resonant and a non-resonant B field probes as well as a non-resonant E field probe. Simulations using a finite-difference time domain solver were compared with the experimental findings. When the body coil was used for excitation, we observed heating around the 15 cm wire at various anatomical locations (both within and outside of the active volume of the head coil). Outside its active area, no such heating was observed while using the Tx/Rx head coil for excitation. The E and B fields of the Tx/Rx birdcage head coil extended well-beyond the physical dimensions of the coil. In air, the fields were monotonically decreasing, while in gel they were more complex with local maxima at the end of the ASTM phantom. These experimental findings were line with the simulations. While caution must always be exercised when scanning individuals with metallic implants, these findings support the use of the Tx/Rx birdcage head coil in place of the body coil at 3T in order to reduce the risk of heating in and around conductive implants that are remote from the head coil.
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Abstract
UNLABELLED Methodology has been evolving for the testing of disinfectants against bacterial single-species biofilms, as the difficulty of biofilm remediation continues to gain much-needed attention. Bacterial single-species biofilm contamination presents a real risk to good manufacturing practice-regulated industries. However, mixed-species biofilms and biofilms containing bacterial spores remain an even greater challenge for cleaning and disinfection. Among spore-forming microorganisms frequently encountered in pharmaceutical manufacturing areas, the spores of Bacillus cereus are often determined to be the hardest to disinfect and eradicate. One of the reasons for the low degree of susceptibility to disinfection is the ability of these spores to be encapsulated within an exopolysachharide biofilm matrix. In this series of experiments, we evaluated the disinfectant susceptibility of B. cereus biofilms relative to disassociated B. cereus spores and biofilm from a non-spore-forming species. Further, we assessed the impact that pre-cleaning has on increasing that susceptibility. LAY ABSTRACT Methodology has been evolving for the testing of disinfectants against bacterial single-species biofilms, as the difficulty of biofilm remediation continues to gain much-needed attention. Bacterial single-species biofilm contamination presents a real risk to good manufacturing practice-regulated industries. However, mixed-species biofilms and biofilms containing bacterial spores remain an even greater challenge for cleaning and disinfection. Among spore-forming microorganisms frequently encountered in pharmaceutical manufacturing areas, the spores of Bacillus cereus are often determined to be the hardest to disinfect and eradicate. One of the reasons for the low degree of susceptibility to disinfection is the ability of these spores to be encapsulated within an exopolysachharide biofilm matrix. In this series of experiments, we evaluated the disinfectant susceptibility of B. cereus biofilms relative to disassociated B. cereus spores and biofilm from a non-spore-forming species. Further, we assessed the impact that pre-cleaning has on increasing that susceptibility.
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Evidence of melatonin synthesis in the ram reproductive tract. Andrology 2016; 4:163-71. [PMID: 26742835 DOI: 10.1111/andr.12117] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 09/04/2015] [Accepted: 09/07/2015] [Indexed: 12/24/2022]
Abstract
Melatonin is a ubiquitous molecule found in a wide range of fluids, one of them being ram seminal plasma, in which it can reach higher concentrations than those found in blood, suggesting an extrapineal secretion by the reproductive tract. In order to identify the source of the melatonin found in ram seminal plasma, we first tried to determine whether the melatonin levels were maintained during the day. For this purpose, melatonin concentrations were measured in seminal plasma obtained from first ejaculates of six rams at 6:00 a.m. in total darkness, at 10:00 a.m. and at 14:00 p.m. The melatonin concentration was higher (p < 0.05) in ejaculates collected at 6:00 a.m. than at 10:00 and 14:00. There was no statistical difference between the latter. To further corroborate an extrapineal secretion of melatonin, the presence of the two key enzymes involved in melatonin synthesis, arylalkylamine-N-acetyltransferase (AANAT) and N-acetylserotonin-O-methyltransferase (ASMT) was analyzed by RT-PCR, q-PCR and Western-blot in ram testes, epididymis, and accessory glands. The RT-PCR showed the presence of the m-RNA codifying both AANAT and ASTM in all the tissues under study, but the q-PCR and Western-blot revealed that gene expression of these enzymes was significantly higher in the testis (p < 0.05). Immunohistochemistry confirmed the presence of AANAT and ASMT in the testis and revealed that they were found in the Leydig cells, spermatocytes, and spermatids. Also, measurable levels of melatonin were found in testicular tissue and the tail of the epididymis. In conclusion, our study indicates that the testes are one of the likely sources of the high levels of melatonin found in ram seminal plasma, at least during the day.
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Comparison of 3 in vivo methods for assessment of alcohol-based hand rubs. Am J Infect Control 2015; 43:506-9. [PMID: 25726133 DOI: 10.1016/j.ajic.2015.01.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 01/21/2015] [Accepted: 01/22/2015] [Indexed: 10/24/2022]
Abstract
BACKGROUND Alcohol-based hand rubs (ABHRs) are the primary method of hand hygiene in health-care settings. ICPs increasingly are assessing ABHR product efficacy data as improved products and test methods are developed. As a result, ICPs need better tools and recommendations for how to assess and compare ABHRs. METHODS Two ABHRs (70% ethanol) were tested according to 3 in vivo methods approved by ASTM International: E1174, E2755, and E2784. Log10 reductions were measured after a single test product use and after 10 consecutive uses at an application volume of 2 mL. RESULTS The test method used had a significant influence on ABHR efficacy; however, in this study the test product (gel or foam) did not significantly influence efficacy. In addition, for all test methods, log10 reductions obtained after a single application were not predictive of results after 10 applications. CONCLUSIONS Choice of test method can significantly influence efficacy results. Therefore, when assessing antimicrobial efficacy data of hand hygiene products, ICPs should pay close attention to the test method used, and ensure that product comparisons are made head to head in the same study using the same test methodology.
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Automated acid and base number determination of mineral-based lubricants by fourier transform infrared spectroscopy: commercial laboratory evaluation. SLAS Technol 2014; 19:577-86. [PMID: 25271046 DOI: 10.1177/2211068214551825] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The Fluid Life Corporation assessed and implemented Fourier transform infrared spectroscopy (FTIR)-based methods using American Society for Testing and Materials (ASTM)-like stoichiometric reactions for determination of acid and base number for in-service mineral-based oils. The basic protocols, quality control procedures, calibration, validation, and performance of these new quantitative methods are assessed. ASTM correspondence is attained using a mixed-mode calibration, using primary reference standards to anchor the calibration, supplemented by representative sample lubricants analyzed by ASTM procedures. A partial least squares calibration is devised by combining primary acid/base reference standards and representative samples, focusing on the main spectral stoichiometric response with chemometrics assisting in accounting for matrix variability. FTIR(AN/BN) methodology is precise, accurate, and free of most interference that affects ASTM D664 and D4739 results. Extensive side-by-side operational runs produced normally distributed differences with mean differences close to zero and standard deviations of 0.18 and 0.26 mg KOH/g, respectively. Statistically, the FTIR methods are a direct match to the ASTM methods, with superior performance in terms of analytical throughput, preparation time, and solvent use. FTIR(AN/BN) analysis is a viable, significant advance for in-service lubricant analysis, providing an economic means of trending samples instead of tedious and expensive conventional ASTM(AN/BN) procedures.
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Controlled vocabularies and ontologies in proteomics: overview, principles and practice. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1844:98-107. [PMID: 23429179 PMCID: PMC3898906 DOI: 10.1016/j.bbapap.2013.02.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 02/05/2013] [Accepted: 02/09/2013] [Indexed: 11/30/2022]
Abstract
This paper focuses on the use of controlled vocabularies (CVs) and ontologies especially in the area of proteomics, primarily related to the work of the Proteomics Standards Initiative (PSI). It describes the relevant proteomics standard formats and the ontologies used within them. Software and tools for working with these ontology files are also discussed. The article also examines the "mapping files" used to ensure correct controlled vocabulary terms that are placed within PSI standards and the fulfillment of the MIAPE (Minimum Information about a Proteomics Experiment) requirements. This article is part of a Special Issue entitled: Computational Proteomics in the Post-Identification Era. Guest Editors: Martin Eisenacher and Christian Stephan.
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Comparison of the Activity of Alcohol-Based Handrubs Against Human Noroviruses Using the Fingerpad Method and Quantitative Real-Time PCR. FOOD AND ENVIRONMENTAL VIROLOGY 2011; 3:35-42. [PMID: 35255643 DOI: 10.1007/s12560-011-9053-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Accepted: 02/01/2011] [Indexed: 06/14/2023]
Abstract
Noroviruses (NoV) are the most common cause of acute nonbacterial gastroenteritis in the United States, and human hands play an important role in their transmission. Little is known about the efficacy of hand hygiene agents against these highly infectious pathogens. We investigated the activity of seven commercially available hand hygiene products against human noroviruses by in vivo fingerpad tests. The in vivo activity of alcohol-based handrubs ranged from 0.10 to 3.74 log reduction and was not solely dependent on alcohol concentration. A handrub (VF481) based on 70% ethanol and a blend of other skin care ingredients reduced Norwalk virus (NV) by 3.74 log in 15 s and provided significantly greater NV reduction than all the other products tested (P < 0.001). Furthermore, VF481 was the most effective product tested against the NoV genogroup II strains Snow Mountain virus (GII.2) and a GII.4 strain. These results demonstrate that alcohol by itself is not effective against NoV, but effective formulation of alcohol-based handrubs can achieve significant reduction of norovirus RNA on fingers.
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Abstract
Standards are important tools in evaluating and predicting the performance of medical devices prior to implantation. There are three types of standards that are available: a material specification, a standard test method, and a standard test guide. Each of these types of standards is defined with examples of how each is used to facilitate evaluation of medical devices. The standards development process is also described: this is a complex process, requiring the involvement of a multidisciplinary team, usually consisting of engineers, scientists, and clinicians who represent healthcare, academia, government, and industry. Finally, standards have a clear and defined role in the development of medical devices, and the benefits, strengths, as well as the limitations in this role are discussed.
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