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1.
Phys Rev Lett ; 132(18): 182502, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38759198

ABSTRACT

The observation of neutrinoless double-beta (0νßß) decay would offer proof of lepton number violation, demonstrating that neutrinos are Majorana particles, while also helping us understand why there is more matter than antimatter in the Universe. If the decay is driven by the exchange of the three known light neutrinos, a discovery would, in addition, link the observed decay rate to the neutrino mass scale through a theoretical quantity known as the nuclear matrix element (NME). Accurate values of the NMEs for all nuclei considered for use in 0νßß experiments are therefore crucial for designing and interpreting those experiments. Here, we report the first comprehensive ab initio uncertainty quantification of the 0νßß-decay NME, in the key nucleus ^{76}Ge. Our method employs nuclear strong and weak interactions derived within chiral effective field theory and recently developed many-body emulators. Our result, with a conservative treatment of uncertainty, is an NME of 2.60_{-1.36}^{+1.28}, which, together with the best-existing half-life sensitivity and phase-space factor, sets an upper limit for effective neutrino mass of 187_{-62}^{+205} meV. The result is important for designing next-generation germanium detectors aiming to cover the entire inverted hierarchy region of neutrino masses.

2.
Farm. comunitarios (Internet) ; 16(1): 61-64, Ene. 2024. tab
Article in Spanish | IBECS | ID: ibc-229282

ABSTRACT

Los Sistemas Personalizados de Dosificación (SPD) son una herramienta eficaz, segura y homologada para el reacondicionamiento de fármacos en farmacia comunitaria. Estos implican la revisión del uso del medicamento (RUM) y la colaboración con el médico de atención primaria (MAP). En el presente artículo se describe el caso de una paciente de 57 años intervenida de lumbociatalgia en 2021 y 2022, con dolor crónico mal controlado y aturdimiento derivado del olvido y/o duplicidad de las tomas. Durante la dispensación habitual se detectan estos problemas relacionados con el medicamento (PRM) y se deriva a la paciente al servicio SPD. Tras la implantación del mismo, la paciente mejora a nivel cognitivo, eliminando el aturdimiento y controlando el dolor, lo que supuso un aumento en su calidad de vida. En conclusión, se destaca la importancia de los diferentes servicios disponibles en la farmacia para mejorar la calidad de vida del paciente, la adherencia al tratamiento y la detección de PRM. (AU)


Monitored Dosage Systems (MDS) are an efficient, reliable and approved device for drug reconditioning in pharmacy. These systems imply a review on proper drug use and the collaboration between primary health care and pharmacists. The case study describes a female patient with a surgical intervention due to lumbosciatica in 2021 and 2022. Patient describes uncontrolled chronic pain and confusion related to improper drug use. During regular dispensing of her medication, these medicine-related problems (MRP) were detected and the patient was referred to the MDS service. After its implementation, the patient’s confusion was eliminated and pain management was achieved, increasing her quality of life. As a conclusion, the different health services provided by the pharmacy can improve a patient’s quality of life, treatment adherence and MRP detection. (AU)


Subject(s)
Humans , Female , Middle Aged , Treatment Adherence and Compliance , Polypharmacy , Dosage Forms , Quality of Life , Drug Dosage Calculations
3.
Article in English | MEDLINE | ID: mdl-37980228

ABSTRACT

INTRODUCTION: The mothers of newborns who are discharged from a neonatal intensive care unit (NICU) experience stress and anxiety due to the specialized care their child requires at home, affecting their perception of maternal self-efficacy. OBJECTIVE: To evaluate the effect of the nursing intervention called Hospital Discharge Plan (HDP) on the promotion of self-efficacy in mothers of newborns discharged from the NICU. METHOD: Quantitative study, quasi-experimental design with pre-test/post-test in a single group, using the Parental Evaluation Scale applied to a convenience sample of 72 mothers of high-risk newborns from a NICU located in the city of Villavicencio (Colombia). The first measurement was taken between days 3 and 4 before discharge and at 15 days' post-discharge. Data processing was carried out using the statistical program SPSS, version 21. The intervention was based on the four concepts of self-efficacy by Barbara Resnick. RESULTS: The perception of maternal self-efficacy before the intervention showed a median of 8.9 points (RI 7.6-9.5); after the intervention it showed a median of 9.6 points (RI of 10-8.7); a statistically significant p-value<0.001 was obtained before and after the intervention with the Wilcoxon rank test. CONCLUSIONS: Education and follow-up promoted the development of knowledge and skills in mothers for the care of high-risk newborns. This contributed to the experience of mastery and vicarious experience from the teaching-learning process and contact with the experience of other mothers, which contributes to the effective development of motherhood.

4.
Radiat Prot Dosimetry ; 199(15-16): 1707-1709, 2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37819287

ABSTRACT

Individual monitoring of external radiation is an activity usually regulated by national regulatory bodies in most countries. Regulations generally contain technical requirements to be met by the individual monitoring services (IMS), in order to ensure that the measurements are correct and therefore the dosimetry results are reliable. In some countries, the requirements include or even consist of the accreditation of the service according to the standard ISO/IEC 17025: 'General requirements for the competence of testing and calibration laboratories.' It is a fact that accreditation is a growing trend among European IMS as a way to guarantee confidence in their technical competence. The acceptance of the dosimetry results between countries and their indentation in the respective National Dose Registries is facilitated if laboratories conform to the ISO/IEC 17025 standard. In the framework of the activities of EURADOS (European Radiation Dosimetry Group) working group 2 'Harmonization of Individual Monitoring in Europe' and attending to the concern of many European IMS in the process of accreditation, a guide has been prepared. The purpose was to assist and encourage IMS to apply for accreditation and to share the authors' own experience with the process. The guide intends to be a practical reference for IMS on how to interpret and implement the ISO/IEC 17025 requirements to the specific activity of a personal dosimetry service for external radiation, emphasizing those aspects of special interest. It includes examples from dosimetry laboratories already accredited. The major novelties from a new edition of ISO/IEC 17025: 2017 are also identified in the guide. Finally, the guide aims to assist the auditing process, giving examples of auditor's questions and how to show evidence of compliance. The main findings are presented.


Subject(s)
Laboratories , Radiometry , Quality Control , Radiometry/methods , Europe , Accreditation
5.
Sci Rep ; 13(1): 12291, 2023 Jul 29.
Article in English | MEDLINE | ID: mdl-37516795

ABSTRACT

The nuclear shell model is one of the prime many-body methods to study the structure of atomic nuclei, but it is hampered by an exponential scaling on the basis size as the number of particles increases. We present a shell-model quantum circuit design strategy to find nuclear ground states by exploiting an adaptive variational quantum eigensolver algorithm. Our circuit implementation is in excellent agreement with classical shell-model simulations for a dozen of light and medium-mass nuclei, including neon and calcium isotopes. We quantify the circuit depth, width and number of gates to encode realistic shell-model wavefunctions. Our strategy also addresses explicitly energy measurements and the required number of circuits to perform them. Our simulated circuits approach the benchmark results exponentially with a polynomial scaling in quantum resources for each nucleus. This work paves the way for quantum computing shell-model studies across the nuclear chart and our quantum resource quantification may be used in configuration-interaction calculations of other fermionic systems.

6.
Plant Biol (Stuttg) ; 22(1): 47-54, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31498556

ABSTRACT

Tropospheric ozone (O3 ) is considered a major air pollutant having negative effects on plant growth and productivity. Background concentrations are expected to rise in several regions of the world in the next 50 years, affecting plant responses to diseases, thus requiring new management strategies for food production. The effects of elevated O3 on the severity of a bacterial disease, and the effectiveness of a chemical defence inducer, were examined in two cultivars of tomato, Roma and Moneymaker, which present different tolerance to this pollutant. The two cultivars differ in their ability to produce and accumulate reactive oxygen species (ROS) in leaf tissues. Tomato plants were challenged with a strain of Xanthomonas vesicatoria, Xv9, which is pathogenic on tomato. Ozone consistently increased severity of the disease by over 40% in both cultivars. In the more tolerant cultivar, O3 pollution increased disease intensity, even after applying a commercially available product to enhance resistance (acibenzolar-S-methyl, BTH). In the more susceptible cultivar, level of disease attained depended on the oxidative balance that resulted from other stress factors. The antioxidant capacity of the plant at the time of infection was relevant for controlling development of the disease. Our results suggest that development of O3 tolerance in commercial crops might impose a penalty cost in terms of disease management under projected higher O3 concentrations.


Subject(s)
Host-Pathogen Interactions , Ozone , Solanum lycopersicum , Bacterial Physiological Phenomena/drug effects , Host-Pathogen Interactions/drug effects , Solanum lycopersicum/drug effects , Solanum lycopersicum/microbiology , Ozone/toxicity , Plant Diseases/prevention & control , Plant Leaves/microbiology
7.
Appl Radiat Isot ; 153: 108843, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31404764

ABSTRACT

Deconvolution analysis of the thermoluminiscent (TL) glow curves proved to be a good complementary method to characterize the individual glow peaks by fitting their kinetic parameters. In this work, new software has been developed for the automatic deconvolution of TL glow curves, assuming either discrete or continuous distribution of trapping centres. The guess estimation of the kinetic parameters is done automatically and can be manually modified, thus allowing the use of the software for routine, processing a large number of measurements, as well as for research purposes. The equations, the methods and the results of the first test are described in detail. The software has been developed by integrating Fortran code and Visual Studio tools to create a graphic easy-to-use environment and permits to obtain the fitted values for the parameters according to the considered model.

8.
Talanta ; 188: 349-355, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30029386

ABSTRACT

Two different computer vision-based analytical chemistry (CVAC) methods were developed to quantify iron in the commercial pharmaceutical formulations Ferbisol® and Ferro sanol®. The methods involve using a digital camera or a desktop scanner to capture a digital image of a series of Fe2+ standard solutions and the unknown sample upon reaction with o-phenanthroline. The images are processed with appropriate software (e.g., the public domain programme ImageJ, from NIH) to obtain a numerical value (analytical signal) based on colour intensity. The fact that such a value is proportional to the analyte concentration allows one to construct a calibration graph from the standards and interpolate the value for the sample in order to determine its concentration. The results thus obtained were compared with those provided by a spectrophotometric method and the US Pharmacopoeia's recommended method. The differences never exceeded 2%. The two proposed methods are simple and inexpensive; also, they provide an effective instrumental alternative to spectrophotometric methods which can be especially beneficial in those cases where purchasing and maintaining a spectrophotometer is unaffordable.


Subject(s)
Colorimetry/methods , Ferrous Compounds/analysis , Glycine/analogs & derivatives , Iron/analysis , Calibration , Ferrous Compounds/chemistry , Glycine/analysis , Glycine/chemistry , Iron/chemistry , Limit of Detection , Phenanthrolines/chemistry , Photography , Software
9.
Radiat Prot Dosimetry ; 170(1-4): 86-9, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26763903

ABSTRACT

The European Dosimetry Group (EURADOS) first started performing international intercomparisons for whole-body dosemeters for individual monitoring services in 1998. Since 2008, these whole-body intercomparisons have been performed on a regular basis. In this latest intercomparison (IC2014), 96 monitoring services from 35 countries (mostly European) participated with 112 dosimetry systems. Unlike in the previous intercomparisons, the whole registration, communication and data exchange process was handled by a new on-line platform. All dosemeter irradiations were carried out in the Seibersdorf accredited dosimetry laboratory. The irradiation plan consisted of nine irradiation setups with five different photon radiation qualities (S-Cs, S-Co, RQR7, W-80 and W-150) and two different angles of radiation incidence (0° and 60°). The paper describes and analyses the individual results for the personal dose equivalent quantities Hp(10) and if requested, Hp(0.07), for all participating systems and compares these results with the ISO 14146 'trumpet curve' performance criteria. The results show that 100 systems (89 % of all systems) do fulfil the general ISO 14146 performance criteria. This paper gives an overview on the performance of the participating individual monitoring services and the influence of the dosemeter type on the observed response values.


Subject(s)
Radiation Dosage , Radiation Dosimeters , Radiation Monitoring/instrumentation , Radiation Protection/methods , Calibration , Computer Systems , Europe , Humans , Luminescence , Photons , Radiation Monitoring/methods , Radiation Protection/instrumentation , Reproducibility of Results , Thermoluminescent Dosimetry/methods , Whole-Body Counting/instrumentation
10.
Radiat Prot Dosimetry ; 170(1-4): 90-4, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26763905

ABSTRACT

In 2008 the European Radiation Dosimetry Group (EURADOS) started a new programme of intercomparisons for individual monitoring services (IMS). The aim was to provide the possibility to IMS in Europe to participate in dosimetry intercomparions with regular time intervals with all types of dosemeter systems that are used routinely to monitor workers for exposure to external radiation. A self-evaluation of the programme shows that, apart from a few problems encountered, the programme can be judged as fit for its purpose. The results of a questionnaire among the participants support this conclusion. The conclusions encourage EURADOS to continue this programme of self-sustained intercomparisons for IMS.


Subject(s)
Radiation Dosage , Radiation Monitoring/methods , Radiation Protection/methods , Europe , Humans , International Cooperation , Photons , Quality Control , Radiation Dosimeters , Reference Values , Surveys and Questionnaires
11.
Radiat Prot Dosimetry ; 170(1-4): 70-3, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26567323

ABSTRACT

In 2008, the CIEMAT Radiation Dosimetry Service decided to implement a quality management system, in accordance with established requirements, in order to achieve ISO/IEC 17025 accreditation. Although the Service comprises the approved individual monitoring services of both external and internal radiation, this paper is specific to the actions taken by the External Dosimetry Service, including personal and environmental dosimetry laboratories, to gain accreditation and the reflections of 3 y of operational experience as an accredited laboratory.


Subject(s)
Accreditation , Laboratories/standards , Radiometry/instrumentation , Calibration , Europe , Humans , International Agencies , Laboratories/organization & administration , Occupational Exposure/prevention & control , Occupational Exposure/standards , Quality Control , Radiation Dosimeters , Radiation Protection/methods , Radiation Protection/standards , Radiometry/standards , Spain , Thermoluminescent Dosimetry/instrumentation , Thermoluminescent Dosimetry/standards
12.
Radiat Prot Dosimetry ; 170(1-4): 326-30, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26276808

ABSTRACT

This communication describes a recently developed single-exposure neutron spectrometer, based on multiple active thermal neutron detectors located within a moderating sphere, which have been developed jointly by CIEMAT (Spain), INFN (Italy) and Politecnico di Milano (Italy) in the framework of Italian and Spanish collaboration projects. The fabricated prototypes permit to achieve spectrometric resolution with nearly isotropic response for neutron with energies from thermal to 100-200 MeV, thus being able to characterise the complete neutron spectrum in only one exposure by unfolding the measured responses of the detectors. This makes it especially advantageous for characterising neutron fields and workplace monitoring purposes in neutron-producing facilities.


Subject(s)
Occupational Exposure/analysis , Radiation Dosage , Radiation Dosimeters , Radiation Monitoring/instrumentation , Radiation Protection/instrumentation , Spectrum Analysis/instrumentation , Calibration , Humans , Italy , Neutrons , Occupational Exposure/prevention & control , Photons , Polyethylene , Radiation Monitoring/methods , Radiation Protection/methods , Reproducibility of Results , Spain , Workplace
13.
EJVES Short Rep ; 33: 27-31, 2016.
Article in English | MEDLINE | ID: mdl-28856321

ABSTRACT

BACKGROUND: Osteochondroma is the most common non-malignant tumour of bone, accounting for approximately one third of benign lesions in the skeleton. They often develop around the knee in the distal femur and in the proximal tibia and fibula. They present as a painless slow growing mass during adolescence and have been reported to cause damage to adjacent structures such as blood vessels; arterial damage is more common than venous injury and is usually a result of compression, stretching, and rubbing of the arterial wall. Such lesions include stenosis, thrombosis, and pseudoaneurysm formation possibly causing lower limb claudication or acute limb ischemia. METHODS: An 18 year old male patient with a 4 week history of pain, hematoma, and oedema of the left calf without previous trauma is reported. A computed tomography scan (CT) revealed a large popliteal artery pseudoaneurysm and its close relationship to a protrusion of the proximal tibia. RESULTS: The popliteal artery was repaired by an external saphenous patch and the exostosis was removed. The patient had palpable popliteal and distal pulses after surgery and during the first year follow-up. CONCLUSIONS: Tibial osteochondroma should be considered in the differential diagnosis in young patients, among the potential causes of pseudoaneurysm of the femoral or popliteal artery. Surgical repair should be performed to restore normal blood flow with resection of the exostosis to prevent recurrence.

14.
Lett Appl Microbiol ; 55(5): 354-61, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22897794

ABSTRACT

AIMS: The purification and biochemical properties of the 1,4-ß-xylosidase of an oenological yeast were investigated. METHODS AND RESULTS: An ethanol-tolerant 1,4-ß-xylosidase was purified from cultures of a strain of Pichia membranifaciens grown on xylan at 28°C. The enzyme was purified by sequential chromatography on DEAE cellulose and Sephadex G-100. The relative molecular mass of the enzyme was determined to be 50kDa by SDS-PAGE. The activity of 1,4-ß-xylosidase was optimum at pH 6·0 and at 35°C. The activity had a Km of 0·48±0·06mmol l(-1) and a Vmax of 7·4±0·1µmol min(-1)mg(-1) protein for p-nitrophenyl-ß-d-xylopyranoside. CONCLUSIONS: The enzyme characteristics (pH and thermal stability, low inhibition rate by glucose and ethanol tolerance) make this enzyme a good candidate to be used in enzymatic production of xylose and improvement of hemicellulose saccharification for production of bioethanol. SIGNIFICANCE AND IMPACT OF THE STUDY: This study may be useful for assessing the ability of the 1,4-ß-xylosidase from P. membranifaciens to be used in the bioethanol production process.


Subject(s)
Ethanol/metabolism , Glucose/metabolism , Pichia/enzymology , Xylose/biosynthesis , Xylosidases/biosynthesis , Electrophoresis, Polyacrylamide Gel , Hydrogen-Ion Concentration , Pichia/metabolism , Substrate Specificity , Xylosidases/isolation & purification , Xylosidases/metabolism
15.
Arq. bras. med. vet. zootec ; 64(2): 427-433, abr. 2012.
Article in English | LILACS | ID: lil-622497

ABSTRACT

The aim of this research work was to investigate the influence of fish oil supplementation on the concentration of conjugated linoleic acid (CLA) and omega 6 and 3 in samples of buffalo milk. A total of 24 female buffaloes separated at random into three groups were fed for 49 days with: natural pasture (group I), supplemented with 70mL of fish oil (group II) and 140mL of fish oil (group III). In the experiment the concentration of CLA showed differences (P<0.05) among the three groups, with a maximum of 7.14mg/g fat in group II. No significant differences were found in omega-6 among the three groups. The highest value of 3.82mg/g fat corresponded to group I, whicht had not been supplemented with fish oil. Significant differences were observed in omega 3 (P<0.05) in groups II and III with respect to group I. The highest average value of 2.42mg/g fat was obtained in group III. The closest relationship omega 6/3 (1.37:1) was observed in group III. As a result, the diets of groups II and III, which included fish oil, increased significantly the content of CLA and omega 3 with reductions in levels of omega 6.


Estudou-se a influência da suplementação com óleo de peixe sobre a concentração dos ácidos graxos ômega 6 e 3, mostrado no leite de búfala. Foram utilizadas 24 búfalas aleatoriamente selecionadas e distribuídas em três grupos e alimentados com pastagem natural por 49 dias com: nenhum suplemento (grupo I), suplementado com 70mL de óleo de peixe (grupo II) e com 140mL de óleo de peixe (grupo III). A concentração de CLA diferiu (P<0,05) entre os três grupos, com valores máxima de até 7,14mg/g de gordura no grupo II. Não foram observadas diferenças significativas para os ácidos graxos omega 6, sendo o maior valor de 3,82mg/g de gordura no grupo I. Foi observada diferença significativa quanto aos ácidos graxos ômega 3 (P<0,05) nos grupos II e III em relação ao grupo I. O mais elevado valor, 2,42mg/g de gordura foi observado no grupo III. A relação ômega 6/3 mais estreita, 1,37:1, foi observada no grupo III. Os resultados mostram que os animais dos grupos II e III que receberam suplementação de óleo de peixe aumentou significativamente o teor de CLA e de omega 3, com diminuição de omega 6.

16.
Talanta ; 83(5): 1575-9, 2011 Feb 15.
Article in English | MEDLINE | ID: mdl-21238754

ABSTRACT

A quantitative analytical imaging approach for determining the nickel content of metallic meteorites is proposed. The approach uses a digital image of a series of standard solutions of the nickel-dimethylglyoxime coloured chelate and a meteorite sample solution subjected to the same treatment as the nickel standards for quantitation. The image is processed with suitable software to assign a colour-dependent numerical value (analytical signal) to each standard. Such a value is directly proportional to the analyte concentration, which facilitates construction of a calibration graph where the value for the unknown sample can be interpolated to calculate the nickel content of the meteorite. The results thus obtained were validated by comparison with the official, ISO-endorsed spectrophotometric method for nickel. The proposed method is fairly simple and inexpensive; in fact, it uses a commercially available digital camera as measuring instrument and the images it provides are processed with highly user-friendly public domain software (specifically, ImageJ, developed by the National Institutes of Health and freely available for download on the Internet). In a scenario dominated by increasingly sophisticated and expensive equipment, the proposed method provides a cost-effective alternative based on simple, robust hardware that is affordable and can be readily accessed worldwide. This can be especially advantageous for countries were available resources for analytical equipment investments are scant. The proposed method is essentially an adaptation of classical chemical analysis to current, straightforward, robust, cost-effective instrumentation.


Subject(s)
Iron/chemistry , Meteoroids , Colorimetry/economics , Spectrophotometry/economics
17.
Radiat Prot Dosimetry ; 144(1-4): 275-81, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21196458

ABSTRACT

This paper presents the results of an intercomparison for extremity dosemeters organised by the European radiation dosimetry group in 2009. In total, 59 systems were tested during this exercise including ring, stall and wrist dosemeters. A total of 1652 dosemeters were irradiated in the selected fields of photons and beta radiation qualities on appropriate phantoms (ISO finger and pillar phantom) in the dose quantity H(p)(0.07). All irradiations were carried out in selected accredited reference dosemetry laboratories (Seibersdorf Laboratories, Austria and IRSN, France). The results show that, especially at low-energy beta radiations ((85)Kr) and for beta irradiations with large angles of incidence (60°), many tested systems show pronounced under responses. On the other hand, for photon irradiations down to energies of 16 keV most systems showed good results. A participants meeting was held at IM2010 with discussion on both general aspects of this intercomparison and specific problems.


Subject(s)
Film Dosimetry/standards , Radiation Monitoring/standards , Radiation Protection/standards , Radiometry/standards , Ankle/radiation effects , Europe , Film Dosimetry/methods , Humans , Phantoms, Imaging , Photons , Quality Control , Radiation Dosage , Radiation Monitoring/methods , Radiation Protection/methods , Radiometry/methods , Reproducibility of Results , Whole Body Imaging , Wrist/radiation effects
18.
Radiat Prot Dosimetry ; 144(1-4): 266-74, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21242166

ABSTRACT

Within EURADOS working group 2, a system for self-sustained intercomparisons for individual monitoring services for external radiation was developed. With the intercomparison results, the participants can show compliance within their quality management system, compare their results with those from other participants and develop plans for improvement of their system. The costs of the exercises are covered by the participants fees. In this programme, the first intercomparison exercise for whole-body dosemeters has been executed in 2008 with 62 participating dosimetry systems from participants across Europe. In general, film systems show the largest deviations, although the results of some participants indicate that it is possible to achieve results with a film system with similar quality as for thermoluminescence dosimetry (TLD) systems. A second intercomparison has been organised for extremity dosemeters in 2009. For 2010 it is planned to organise a second intercomparison for whole-body dosemeters.


Subject(s)
Film Dosimetry/standards , Radiation Monitoring/standards , Radiation Protection/standards , Radiometry/standards , Europe , Film Dosimetry/methods , Humans , Program Development , Quality Control , Radiation Dosage , Radiation Monitoring/methods , Radiation Protection/methods , Radiometry/methods , Reproducibility of Results , Surveys and Questionnaires , Whole Body Imaging
19.
Radiat Prot Dosimetry ; 144(1-4): 111-4, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21131328

ABSTRACT

This paper describes the activities realised by the CIEMAT Radiation Dosimetry Service (SDR) for the implementation of a quality management system (QMS) in order to achieve compliance with the requirements of ISO/IEC 17025 and to apply for the accreditation for testing measurements of radiation dose. SDR has decided the accreditation of the service as a whole and not for each of its component laboratories. This makes it necessary to design a QMS common to all, thus ensuring alignment and compliance with standard requirements, and simplifying routine works as possible.


Subject(s)
Radiation Monitoring/standards , Radiation Protection/standards , Radiometry/standards , Accreditation , Databases, Factual , Humans , Laboratories/standards , Program Development , Quality Control , Radiation Dosage , Radiation Monitoring/methods , Radiation Protection/methods , Radioisotopes/analysis , Radiometry/methods , Total Quality Management
20.
J Antimicrob Chemother ; 65(12): 2548-55, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20956354

ABSTRACT

OBJECTIVES: This study focuses on the mechanism of interaction of sitamaquine with Leishmania donovani membranes, and its accumulation within the parasites. METHODS: A biomimetic model of the outer layer of a Leishmania plasma membrane was used to examine the interactions of sitamaquine with lipids. The plasma membranes of L. donovani promastigotes were depleted of sterol using cholesterol oxidase, in order to assess the importance of sterols in drug-membrane interactions. Sterols were quantified and sitamaquine susceptibility was assessed using the MTT test. Kinetics of sitamaquine accumulation and efflux were measured under different conditions. RESULTS: Sitamaquine interacts first with phospholipid anionic polar head groups and then with phospholipid acyl chains to insert within biological membranes and accumulates rapidly in the Leishmania cytosol according to a sterol-independent process. The rapid sitamaquine efflux observed was related to an energy-dependent mechanism since the intracellular amount of sitamaquine was enhanced three times in the absence of glucose and the efflux was inhibited in energy-depleted conditions. (1)H NMR analysis of motile lipid showed that sitamaquine did not affect lipid trafficking in Leishmania. CONCLUSIONS: We propose that sitamaquine rapidly accumulates in Leishmania by diffusion along an electrical gradient and is concentrated in the cytosol by an energy- and sterol-independent process. The affinity of sitamaquine for membranes was transitory and an energy-dependent efflux was demonstrated, suggesting the presence of an as yet uncharacterized transporter.


Subject(s)
Aminoquinolines/metabolism , Antiprotozoal Agents/metabolism , Cell Membrane/metabolism , Leishmania donovani/drug effects , Aminoquinolines/chemistry , Aminoquinolines/pharmacology , Animals , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/pharmacology , Biomimetic Materials/chemistry , Biomimetic Materials/metabolism , Cell Membrane/chemistry , Cell Membrane/drug effects , Diffusion , Leishmania donovani/metabolism , Membrane Lipids/chemistry , Membrane Lipids/metabolism , Phospholipids/metabolism , Sterols/metabolism
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