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1.
ACS Sens ; 9(3): 1199-1207, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38372695

RESUMEN

Enzymes are essential to life and indispensable in a wide range of industries (food, pharmaceutical, medical, biosensing, etc.); however, a significant shortcoming of these fragile biological catalysts is their poor stability. To address this challenge, a variety of immobilization methods have been described to enhance the enzyme's stability. These immobilization methods generally are specific to an individual enzyme or optimal for a particular application. The aim of this study is to explore the utility of porous, indicator moiety-tagged, polymeric nanocapsules (NCs) for the encapsulation of enzymes and measurement of the enzyme's substrate. As a model enzyme, glucose oxidase (GOx) is used. The GOx enzyme-loaded, fluorophore-tagged NCs were synthesized by using self-assembled surfactant vesicle templates. To show that the biological activity of GOx is preserved during entrapment, the rate of the GOx enzyme catalyzed reaction was measured. To evaluate the protective features of the porous NCs, the encapsulated GOx enzyme activity was followed in the presence of hydrolytic enzymes. During the encapsulation of GOx and the purification of the GOx-loaded NCs, the GOx activity decayed less than 10%, and up to 30% of the encapsulated GOx activity could be retained for 3-5 days in the presence of hydrolytic enzymes. In support of the potentially unique advantages of the enzyme-loaded NCs, as a proof-of-concept example, the fluorophore-tagged, GOx-loaded NCs were used for the determination of glucose in the concentration range between 18 and 162 mg/dL and for imaging the distribution of glucose concentration in imaging experiments.


Asunto(s)
Nanocápsulas , Enzimas Inmovilizadas , Porosidad , Polímeros , Glucosa , Indicadores y Reactivos , Glucosa Oxidasa
2.
Sensors (Basel) ; 23(19)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37836984

RESUMEN

Physical activity and cardiovascular disease (CVD) are intimately linked. Low levels of physical activity increase the risk of CVDs, including myocardial infarction and stroke. Conversely, when CVD develops, it often reduces the ability to be physically active. Despite these largely understood relationships, the objective measurement of physical activity is rarely performed in routine healthcare. The ability to use sensor-based approaches to accurately measure aspects of physical activity has the potential to improve many aspects of cardiovascular healthcare across the spectrum of healthcare, from prediction, prevention, diagnosis, and treatment to disease monitoring. This review discusses the potential of sensor-based measurement of physical activity to augment current cardiovascular healthcare. We highlight many factors that should be considered to maximise the benefit and reduce the risks of such an approach. Because the widespread use of such devices in society is already a reality, it is important that scientists, clinicians, and healthcare providers are aware of these considerations.


Asunto(s)
Enfermedades Cardiovasculares , Infarto del Miocardio , Accidente Cerebrovascular , Humanos , Factores de Riesgo , Enfermedades Cardiovasculares/terapia , Enfermedades Cardiovasculares/prevención & control , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/terapia , Atención a la Salud , Ejercicio Físico
3.
Health Place ; 83: 103085, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37523876

RESUMEN

BACKGROUND: Few studies have explicitly quantified the proportion of park-based physical activity to park users' overall physical activity levels. Population studies need new context-specific physical activity measurement tools to achieve this. The objective of this study was to develop a reliable measure of self-reported park use and physical activity undertaken within and outside of parks to determine the contribution that park-based physical activity makes to overall physical activity levels. METHODS: A test-retest reliability study (n = 104) was conducted using the Park Physical Activity Questionnaire (Park-PAQ), an instrument based on the Active Australia Survey. Park-PAQ items captured the frequency and duration of walking for recreation or exercise, walking for transport, moderate and vigorous physical activity and strength, conditioning and balance activities done in parks and elsewhere. RESULTS: Recall of doing any walking for recreation (kappa = 0.649, p < 0.001) and any vigorous physical activity (kappa = 0.772, p < 0.001) was 'substantial', recall of doing any moderate physical activity (kappa = 0.553, p < 0.001) was 'moderate/acceptable', and recall of any walking for transport (kappa = 0.840, p < 0.001) 'near perfect'. Recall of the time spent walking for recreation in parks (ICC = 0.928, p < 0.001) was 'near perfect', whilst recall of time spent doing moderate activity in parks (ICC = 0.925, p < 0.001) and vigorous activity in parks (ICC = 0.962, p < 0.001) was 'near perfect'. Time spent walking for transport in a park (ICC = 0.200, p = 0.056) showed 'poor' agreement. Repeatability of the usual level of park use was 'substantial' (kappa = 0.744). CONCLUSIONS: The Park-PAQ reliably measures six domains of physical activity and quantifies the proportion of physical activity done in parks as a proportion of total physical activity. The Park-PAQ, used alone or embedded into park or physical activity surveys, will reliably capture context-specific activities that will optimise population level physical activity interventions, park programming and park management and design.


Asunto(s)
Ejercicio Físico , Recreación , Humanos , Reproducibilidad de los Resultados , Caminata , Encuestas y Cuestionarios , Parques Recreativos , Planificación Ambiental , Características de la Residencia
4.
Int J Chron Obstruct Pulmon Dis ; 18: 1231-1250, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37346078

RESUMEN

Alpha-1 antitrypsin deficiency (AATD) is a hereditary disorder and a genetic risk factor for chronic obstructive pulmonary disease (COPD). Physical activity (PA) is important for the prevention and treatment of chronic disease. Little is known about PA in people with AATD. Therefore, we aimed to map the research undertaken to improve and/or measure PA, sedentary behaviour (SB) or exercise in people with AATD. Searches were conducted in CINAHL, Medline, EMBASE and clinical trial databases for studies published in 2021. Databases were searched for keywords (physical activity, AATD, exercise, sedentary behavior) as well as synonyms of these terms, which were connected using Boolean operators. The search yielded 360 records; 37 records were included for review. All included studies (n = 37) assessed exercise capacity; 22 studies reported the use of the six-minute walk test, the incremental shuttle walk test and cardiopulmonary exercise testing were reported in three studies each. Other objective measures of exercise capacity included a submaximal treadmill test, the Naughton protocol treadmill test, cycle ergometer maximal test, endurance shuttle walk test, constant cycle work rate test, a peak work rate test and the number of flights of stairs a participant was able to walk without stopping. A number of participant self-reported measures of exercise capacity were noted. Only one study aimed to analyze the effects of an intensive fitness intervention on daily PA. One further study reported on an exercise intervention and objectively measured PA at baseline. No studies measured SB. The assessment of PA and use of PA as an intervention in AATD is limited, and research into SB absent. Future research should measure PA and SB levels in people with AATD and explore interventions to enhance PA in this susceptible population.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Deficiencia de alfa 1-Antitripsina , Humanos , Conducta Sedentaria , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/terapia , Tolerancia al Ejercicio , Ejercicio Físico , Deficiencia de alfa 1-Antitripsina/diagnóstico , Deficiencia de alfa 1-Antitripsina/genética , Deficiencia de alfa 1-Antitripsina/terapia , alfa 1-Antitripsina
5.
Appl Radiat Isot ; 199: 110882, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37271088

RESUMEN

As part of the international key comparison CCRI(II)-K2.Cd-109.2021, the BIPM has implemented a specific method to measure the activity of 109Cd solution - a key radionuclide in the calibration of gamma-ray spectrometers. The counting of electrons from internal conversion was carried out using a liquid scintillation counter based on 3-photomultiplier tubes. In this technique, a major part of the uncertainty comes from the overlap between the conversion electrons peak and the peak at lower energy from the other products of the decay. As a result, the energy resolution that the liquid scintillation system can achieve is the most critical challenge to achieving a precise measurement. The study demonstrates the advantage of producing a sum of the signal from the three photomultipliers to enhance the energy resolution and limit the peak overlap. In addition, the spectrum has been processed by a specific unfolding approach to properly separate the spectral components. Thanks to the method introduced in this study, an activity estimation has been realized with a relative standard uncertainty of 0.5%.

6.
J Pharm Biomed Anal ; 229: 115376, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37011552

RESUMEN

Imbalances between proteases and protease inhibitors have been associated with several pathological conditions including emphysema as seen in α1-antitrypsin deficiency. For this pathological condition, unimpeded neutrophil elastase activity has been ascribed a pivotal role in the destruction of lung tissue and thus in disease progression. Therefore, low, or non-quantifiable neutrophil elastase (NE) activity levels determined in bronchoalveolar lavage solutions indicate the success of α1-antitrypsin (AAT) augmentation therapy as NE activity will be erased. To overcome the known limitations of available elastase activity assays regarding sensitivity and selectivity, we developed a new elastase activity assay, which fundamentally relies on the highly specific complex formation between AAT and active elastase. Plate-bound AAT captured active elastase from the sample undergoing complex formation, followed by the immunological detection of human NE. This assay principle facilitated the measurement of low pM amounts of active human NE. The data of the assay performance check demonstrated adequate accuracy and precision profiles meeting currently accepted best practices for this activity assay, which can be classified as a ligand-binding assay. Furthermore, spike-recovery studies at low human NE levels, carried out for three human bronchoalveolar samples, resulted in recoveries within the 100 ± 20% range, while good linearity and parallelism of the samples' dilution-response curves was observed. Altogether, complemented by the data of selectivity and robustness studies and the accuracy and precision profile obtained in buffer, this newly developed human NE activity assay was demonstrated to perform accurately and precisely in clinically relevant samples.


Asunto(s)
Elastasa de Leucocito , alfa 1-Antitripsina , Humanos , alfa 1-Antitripsina/farmacología , alfa 1-Antitripsina/uso terapéutico , Pulmón , Inhibidores de Proteasas , Neutrófilos
7.
Sensors (Basel) ; 23(4)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36850822

RESUMEN

Supervised personal training is most effective in improving the health effects of exercise in older adults. Yet, low frequency (60 min, 1-3 sessions/week) of trainer contact limits influence on behavior change outside sessions. Strategies to extend the effect of trainer contact outside of supervision and that integrate meaningful and intelligent two-way communication to provide complex and interactive problem solving may motivate older adults to "move more and sit less" and sustain positive behaviors to further improve health. This paper describes the experimental protocol of a 16-week pilot RCT (N = 46) that tests the impact of supplementing supervised exercise (i.e., control) with a technology-based behavior-aware text-based virtual "Companion" that integrates a human-in-the-loop approach with wirelessly transmitted sensor-based activity measurement to deliver behavior change strategies using socially engaging, contextually salient, and tailored text message conversations in near-real-time. Primary outcomes are total-daily and patterns of habitual physical behaviors after 16 and 24 weeks. Exploratory analyses aim to understand Companion's longitudinal behavior effects, its user engagement and relationship to behavior, and changes in cardiometabolic and cognitive outcomes. Our findings may allow the development of a more scalable hybrid AI Companion to impact the ever-growing public health epidemic of sedentariness contributing to poor health outcomes, reduced quality of life, and early death.


Asunto(s)
Comunicación , Calidad de Vida , Humanos , Anciano , Proyectos Piloto , Concienciación , Sistemas de Computación , Ensayos Clínicos Controlados Aleatorios como Asunto
8.
Molecules ; 28(3)2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36771012

RESUMEN

44Sc is a promising radionuclide for positron emission tomography (PET) in nuclear medicine. As a part of the implementation of a production site for 44Sc, precise knowledge of the activity of the product is necessary. At the Paul Scherrer Institute (PSI) and the University of Bern (UniBE), 44Sc is produced by enriched 44CaO-target irradiation with a cyclotron. The two sites use different techniques for activity measurement, namely a dose calibrator at the PSI and a gamma-ray spectrometry system at UniBE and PSI. In this work, the 44Sc was produced at the PSI, and samples of the product were prepared in dedicated containers for onsite measurements at PSI, UniBE, and the Institute of Radiation Physics (IRA) in Lausanne for precise activity measurement using primary techniques and for the calibration of the reference ionization chambers. An accuracy of 1% was obtained for the activity measurement, allowing for a precise calibration of the dose calibrator and gamma-ray spectrometry of the two production sites. Each production site now has the capability of measuring 44Sc activity with an accuracy of 2%.

9.
Br J Nutr ; 130(8): 1444-1457, 2023 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36805853

RESUMEN

The European Food Safety Authority has suggested that EU countries implement the 2 × 24 h diet recall (2 × 24 h DR) method and physical activity (PA) measurements for national dietary surveys. Since 2000, Denmark has used 7 d food diaries (7 d FD) with PA questionnaires and measurements. The accuracy of the reported energy intakes (EI) from the two diet methods, pedometer-determined step counts and self-reported time spent in moderate-to-vigorous PA (MVPA) were compared with total energy expenditure measured by the doubly labelled water (TEEDLW) technique and with PA energy expenditure (PAEE), respectively. The study involved fifty-two male and sixty-eight female volunteers aged 18-60 years who were randomly assigned to start with either the 24 h DR or the web-based 7 d FD, and wore a pedometer for the first 7 d and filled in a step diary. The mean TEEDLW (11·5 MJ/d) was greater than the mean reported EI for the 7 d FD (9·5 MJ/d (P < 0·01)) but the same as the 2 × 24 h DR (11·5 MJ/d). The proportion of under-reporters was 34 % (7 d FD) and 4 % (2 × 24 h DR). Most participants preferred the 7 d DR as it was more flexible, despite altering their eating habits. Pearson's correlation between steps corrected for cycling and PAEE was r = 0·44, P < 0·01. Spearman's correlation for self-reported hours spent in MVPA and PAEE was r = 0·58, P < 0·01. The 2 × 24 h DR performs better than the existing 7 d FD method. Pedometer-determined steps and self-reported MVPA are good predictors of PAEE in adult Danes.


Asunto(s)
Dieta , Agua , Adulto , Femenino , Humanos , Masculino , Dinamarca , Registros de Dieta , Ingestión de Energía , Metabolismo Energético , Internet , Adolescente , Adulto Joven , Persona de Mediana Edad
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121876, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36122463

RESUMEN

A fluorescent gold nanocluster was used for determining peroxyl radical scavenging activity of antioxidants. Histidine was used as a green reducing and protective agent, and glutathione (GSH) enhanced the fluorescence intensity of histidine-stabilized gold nanoclusters (AuNCs) by ligand exchange process. When AAPH-induced oxidation of GSH occurred, the initial fluorescence intensity of GSH-capped AuNCs (λex = 450 nm λem = 502 nm) was decreased with static quenching. The decline of fluorescence intensity of the GSH-capped AuNCs upon peroxyl radical attack is diminished with the addition of antioxidants to the reaction medium, the difference in fluorescence intensity being related to peroxyl radical scavenging activity of antioxidants. The 50 % inhibitive concentration of related antioxidant compounds were determined and compared to those of crocin bleaching assay. Inhibition % of sage (Salvia officinalis L.) and green tea (Camellia sinensis) infusions against peroxyl radicals were investigated. The proposed assay can be used for simple and selective estimation of the peroxyl radical scavenging activity in complex matrices, as histidine-stabilized GSH-capped AuNCs were selective toward peroxyl radicals, not affected by other ROS at the studied concentrations.


Asunto(s)
Antioxidantes , Oro , Antioxidantes/farmacología , Histidina , Glutatión , Colorantes , Depuradores de Radicales Libres/farmacología
11.
Artículo en Inglés | MEDLINE | ID: mdl-36361011

RESUMEN

Schools are well-positioned to provide physical activity opportunities to help youth achieve the recommended 60 or more daily minutes of moderate-to-vigorous physical activity. The Children's Physical Activity Research Group (CPARG) at the University of South Carolina has focused on understanding physical activity in school-aged youth for 30+ years. The purpose of this article was to critically review (CPARG) contributions to the field in school settings and school-age youth. We reviewed 127 published CPARG articles from six research projects conducted between 1993-2019. The review was guided by questions in five categories: measurement of physical activity and its determinants, characteristics of physical activity behavior, correlates/determinants of physical activity, physical activity interventions, and race/ethnicity and physical activity. Results were summarized by question and synthesized across categories. CPARG contributions included assessing physical activity levels, patterns, forms, and contexts; identifying and measuring physical activity correlates/determinants; and conducting school-based physical activity interventions. Identifying multiple domains of physical activity determinants enables researchers and practitioners to select/design age-appropriate, valid, and reliable instruments to assess determinants. Focusing on determinants enables them to create effective physical activity interventions, environments, programs, and policies in schools. These efforts must address race/ethnicity differences, ensuring that measurement instruments and intervention strategies are culturally appropriate.


Asunto(s)
Ejercicio Físico , Actividad Motora , Niño , Humanos , Adolescente , Instituciones Académicas
12.
BMC Plant Biol ; 22(1): 478, 2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36207676

RESUMEN

BACKGROUND: A reasonable supply of nitrogen (N) fertilizer is essential for obtaining high-quality, high-level, and stable potato yields, and an improvement in the N utilization efficiency can effectively reduce N fertilizer use. It is important to use accurate, straightforward, and efficient transgenic breeding techniques for the identification of genes that can improve nitrogen use efficiency, thus enabling us to achieve the ultimate goal of breeding N-efficient potato varieties. In recent years, some of the mechanisms of miRNAs have been elucidated via the analysis of the correlation between the expression levels of potato miRNA target genes and regulated genes under conditions of stress, but the role of miRNAs in the inhibition/expression of key genes regulating N metabolism under N stress is still unclear. Our study aimed to identify the role played by specific enzymes and miRNAs in the responses of plants to N stress. RESULTS: The roots and leaves of the N-efficient potato variety, Yanshu4 ("Y"), and N-inefficient potato variety, Atlantic ("D"), were collected at the seedling and budding stages after they were exposed to different N fertilizer treatments. The miRNAs expressed differentially under the two types of N stress and their corresponding target genes were first predicted using miRNA and degradome analysis. Then, quantitative polymerase chain reaction (qRT-PCR) was performed to verify the expression of differential miRNAs that were closely related to N metabolism. Finally, the shearing relationship between stu-miR396-5p and its target gene StNiR was determined by analyzing luciferase activity levels. The results showed that NiR activity increased significantly with an increase in the applied N levels from the seedling stage to the budding stage, and NiR responded significantly to different N treatments. miRNA sequencing enabled us to predict 48 families with conserved miRNAs that were mainly involved in N metabolism, carbon metabolism, and amino acid biosynthesis. The differences in the expression of the following miRNAs were identified via screening (high expression levels and P < 0.05): stu-miR396-5p, stu-miR408b-3p_R-1, stu-miR3627-3p, stu-miR482a-3p, stu-miR8036-3p, stu-miR482a-5p, stu-miR827-5p, stu-miR156a_L-1, stu-miR827-3p, stu-miR172b-5p, stu-miR6022-p3_7, stu-miR398a-5p, and stu-miR166c-5p_L-3. Degradome analysis showed that most miRNAs had many-to-many relationships with target genes. The main target genes involved in N metabolism were NiR, NiR1, NRT2.5, and NRT2.7. qRT-PCR analysis showed that there were significant differences in the expression levels of stu-miR396-5p, stu-miR8036-3p, and stu-miR482a-3p in the leaves and roots of the Yanshu4 and Atlantic varieties at the seedling and budding stages under conditions that involved no N and excessive N application; the expression of these miRNAs was induced in response to N stress. The correlation between the differential expression of stu-miR396-5p and its corresponding target gene NiR was further verified by determining the luciferase activity level and was found to be strongly negative. CONCLUSION: The activity of NiR was significantly positively correlated with N application from the seedling to the budding stage. Differential miRNAs and target genes showed a many-to-many relationship with each other. The expression of stu-miR396-5p, stu-miR482a-3p, and stu-miR8036-3p in the roots and leaves of the Yanshu4 and Atlantic varieties at the seedling and budding stages was notably different under two types of N stress. Under two types of N stress, stu-miR396-5p was down-regulated in Yanshu4 in the seedling-stage and shoot-stage roots, and up-regulated in seedling-stage roots and shoot-stage leaves; stu-miR482a-3p was up-regulated in the seedling and shoot stages. The expression of stu-miR8036-3p was up-regulated in the leaves and roots at the seedling and budding stages, and down-regulated in roots under both types of N stress. The gene expressing the key enzyme involved in N metabolism, StNiR, and the stu-miR396-5p luciferase assay reporter gene had a strong regulatory relationship with each other. This study provides candidate miRNAs related to nitrogen metabolism and highlights that differential miRNAs play a key role in nitrogen stress in potato, providing insights for future research on miRNAs and their target genes in nitrogen metabolic pathways and breeding nitrogen-efficient potatoes.


Asunto(s)
MicroARNs , Solanum tuberosum , Aminoácidos/metabolismo , Carbono/metabolismo , Fertilizantes , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , MicroARNs/genética , MicroARNs/metabolismo , Nitrógeno/metabolismo , Fitomejoramiento , Plantas Modificadas Genéticamente/genética , ARN de Planta/genética , ARN de Planta/metabolismo , Plantones/genética , Solanum tuberosum/genética , Solanum tuberosum/metabolismo
13.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36232405

RESUMEN

Since the 1950s, one of the goals of adipose tissue research has been to determine lipolytic and lipogenic activity as the primary metabolic pathways affecting adipocyte health and size and thus representing potential therapeutic targets for the treatment of obesity and associated diseases. Nowadays, there is a relatively large number of methods to measure the activity of these pathways and involved enzymes, but their applicability to different biological samples is variable. Here, we review the characteristics of mean lipogenic and lipolytic enzymes, their inhibitors, and available methodologies for assessing their activity, and comment on the advantages and disadvantages of these methodologies and their applicability in vivo, ex vivo, and in vitro, i.e., in cells, organs and their respective extracts, with the emphasis on adipocytes and adipose tissue.


Asunto(s)
Lipogénesis , Lipólisis , Adipocitos/metabolismo , Tejido Adiposo/metabolismo , Humanos , Obesidad/metabolismo
14.
Methods Mol Biol ; 2466: 121-133, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35585315

RESUMEN

This protocol describes the isolation of mitochondria by affinity chromatography using magnetic beads coated with Strep-Tactin in a timeframe of ca. 30 min. Compared to a classic differential and density gradient centrifugation this protocol enables a more rapid and efficient isolation of mitochondria even with small amounts of plant material. Transgenic plants with mitochondria that are decorated with a protein that is integrated into the outer mitochondrial membrane and fused to a green fluorescent protein (GFP) and a TwinStrep-tag facing the cytosol. This tag can bind to Strep-Tactin coated magnetic beads. Isolated mitochondria still bound to magnetic beads are uniquely suited for measuring oxygen consumption rates since this measurement needs mitochondria to be immobilized on the bottom of the measuring well. Furthermore, the isolated mitochondria can be used for downstream applications such as proteomics and metabolomics. This technique also allows for the isolation of mitochondria from specific cell types and tissues by altering the expression of the protein decorating the mitochondria.


Asunto(s)
Mitocondrias , Membranas Mitocondriales , Cromatografía de Afinidad/métodos , Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Plantas Modificadas Genéticamente , Proteómica/métodos
15.
EJNMMI Phys ; 9(1): 19, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35286498

RESUMEN

BACKGROUND: 161Tb draws an increasing interest in nuclear medicine for therapeutic applications. More than 99% of the emitted gamma and X-rays of 161Tb have an energy below 100 keV. Consequently, precise activity measurement of 161Tb becomes inaccurate with radionuclide dose calibrators when using inappropriate containers or calibration factors to account for the attenuation of this low energy radiation. To evaluate the ionization chamber response, the sample activity must be well known. This can be performed using standards traceable to the Système International de Référence, which is briefly described as well as the method to standardize the radionuclides. METHODS: In this study, the response of an ionization chamber using different container types and volumes was assessed using 161Tb. The containers were filled with a standardized activity solution of 161Tb and measured with a dedicated ionization chamber, providing an accurate response. The results were compared with standardized solutions of high-energy gamma-emitting radionuclides such as 137Cs, 60Co, 133Ba and 57Co. RESULTS: For the glass vial type with an irregular glass thickness, the 161Tb measurements gave a deviation of 4.5% between two vials of the same type. The other glass vial types have a much more regular thickness and no discrepancy was observed in the response of the ionization chamber for these type of vials. Measurements with a plastic Eppendorf tube showed stable response, with greater sensitivity than the glass vials. CONCLUSION: Ionization chamber measurements for low-energy gamma emitters (< 100 keV), show deviation depending on the container type used. Therefore, a careful selection of the container type must be done for activity assessment of 161Tb using radionuclide dose calibrators. In conclusion, it was highlighted that appropriate calibration factors must be used for each container geometry when measuring 161Tb and, more generally, for low-energy gamma emitters.

16.
BMC Public Health ; 22(1): 332, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35172771

RESUMEN

PURPOSE: To describe the agreement between parent- and adolescent- reports of adolescent moderate-to-vigorous intensity physical activity (MVPA) and to determine sociodemographic factors associated with MVPA reporting differences during the COVID-19 pandemic. METHODS: We analyzed data collected in May 2020 from the Adolescent Brain Cognitive Development Study (ABCD, N = 4841), a U.S. prospective cohort study. We quantified past weekly adolescent MVPA levels as reported by the parent and adolescent (referent). Intra-class correlation coefficients (ICC) and Bland-Altman plots were used to examine the degree of agreement between parent- and adolescent- reports. RESULTS: When quantifying adolescent MVPA during the same recall period, median (p25, p75) MVPA (h∙wk.- 1) was 2.17 (0.00, 6.00) as reported by adolescents and 1.52 (0.29, 4.75) by parents with a mean difference of 4.89. Statistically significant differences in reports of MVPA were found in households with income > $75,000: on average, adolescents reported higher MVPA levels than their parents. Bland-Altman plots illustrated that, among adolescents reporting no or little MVPA, there was higher parent-adolescent agreement. However, among adolescents reporting high levels of MVPA, there was less agreement between the parent- and adolescent- reports. CONCLUSIONS: Despite more time spent together at home during the pandemic, there was generally low agreement between parent- and adolescent- reports of adolescent MVPA. Future research could examine parent-adolescent agreement of MVPA within the context of device-based measures (e.g., accelerometers), determine reasons for differences in parent-adolescent reporting of MVPA, and inform interventions for improved parental involvement and monitoring of MVPA.


Asunto(s)
COVID-19 , Pandemias , Adolescente , Estudios Transversales , Ejercicio Físico , Humanos , Padres , Estudios Prospectivos , SARS-CoV-2
17.
Child Psychiatry Hum Dev ; 53(3): 440-447, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33611737

RESUMEN

Adult physical activity levels influence youth physical activity levels, but the nature of this relationship is still unknown. Most research focusing on this topic has been conducted with accelerometers, which are ideal since self-report physical activity measures can be biased. However, self-report measures for physical activity are useful to include in studies to gather information at low-cost. The purpose of this study was to further develop a self-report adult-youth dyad measure of physical activity. This study was conducted using secondary data analysis of the physical activity measures used in an intervention on behavioral nutrition (iCook 4-H). Participants were a sample of 214 adults (M = 39.0, SD = 8.0 years) and youth (M = 9.4, SD = 0.7 years) pairs. Accelerometer data was collected for a subset of youth (n = 122). There was dependency between the adult-youth physical activity data, and a dyadic confirmatory factor analysis model showed good fit to the data and achieved metric invariance, a measure to determine if the same construct was being measured in both youth and adults. Invariance was confirmed across matched versus unmatched sex pairs and some evidence of invariance with youth accelerometer data. Based on study findings, when using self-report measures of physical activity, researchers should measure both members of the adult-youth dyad to get more accurate measurements. Further validation of these findings is needed using an objective physical activity measure, like accelerometers, with all participants and more diverse samples.


Asunto(s)
Ejercicio Físico , Adolescente , Adulto , Humanos , Autoinforme
18.
BMC Public Health ; 21(1): 1797, 2021 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-34615500

RESUMEN

BACKGROUND: Physical inactivity has been recognised as a global public health problem that requires concerted action. This calls for systematic physical activity (PA) surveillance as a mechanism for assessing the problem and evaluating the effectiveness of related policies. Because countries tend to design their policy measures based on national surveillance data, here we present an inventory of existing national surveillance systems on PA, sedentary behaviour (SB) and sport participation (SP) among adult population in all European Union (EU) Member States. METHODS: As a part of the European Physical Activity and Sports Monitoring System (EUPASMOS) project, a questionnaire was constructed in the form of an on-line survey to collect detailed information on existing national surveillance systems on either PA, SB, or SP. National HEPA focal points from all 27 EU Member States were invited to answer the on-line questionnaire and data collection took part in the period May 2018-September 2019. RESULTS: National monitoring of PA or SB or SP for adults has been established in 16/27 EU Member States, that host 33 different PA/SB/SP monitoring systems. Apart from 3 countries that are using accelerometers (Finland, Ireland and Portugal), surveillance is typically based on questionnaires. In most Member States these questionnaires have not been validated in the particular language and cultural setting. Next, specific domains and dimensions of PA, SB and SP assessed vary a lot across countries. Only 3 countries (the Netherlands, Portugal and Slovenia) are monitoring all three behaviours while covering most of the domains and dimensions of PA/SB/SP. Lastly, as half of the existing surveillance systems set an upper age limit, in 9/16 countries that are monitoring PA/SB/SP, no data for people older than 80 years are available. CONCLUSIONS: Systematic surveillance of PA is lacking among 11/27 EU countries, with even few monitoring SB and SP. Besides, existing surveillance systems typically fail to assess all dimensions and domains of PA/SB/SP with only three countries maintaining monitoring systems that encompass all three behaviours while covering most of the domains and dimensions of PA/SB/SP. Hence, additional efforts in advocacy of systematic PA surveillance in the EU are called for.


Asunto(s)
Conducta Sedentaria , Deportes , Adulto , Anciano de 80 o más Años , Unión Europea , Ejercicio Físico , Humanos , Salud Pública
19.
Appl Radiat Isot ; 178: 109968, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34619627

RESUMEN

The paper summarizes measurements and the Monte Carlo simulations performed to adapt the high purity germanium (HPGe) detectors of the system to the particular tasks of the decommissioning site. The work carried out for the installation and adaptation in CIEMAT of the prototype 'SuperMum', developed in the framework of the European MetroDecom II project for segregation and declassification of materials is described. The activities related to the validation of the prototype for the specific needs of a real Waste Management Unit are presented. Monte Carlo models of the SuperMum have been developed at CIEMAT and CMI using different codes and adapted to the geometries used (big-bag containers with the material volume of up to 0.5 m3). Uncertainty budget reporting tailored for the possible deviations between Monte Carlo assumptions and real waste have been analyzed. Data for several filling levels and activity distributions have been measured with reference sources and a good agreement has been obtained with calculated values.

20.
Rev. cuba. invest. bioméd ; 40(3)sept. 2021. ilus
Artículo en Español | CUMED, LILACS | ID: biblio-1408570

RESUMEN

Introducción: Los estudios epidemiológicos sobre enfermedades no transmisibles en Cuba requieren técnicas que determinen el nivel de actividad física de manera práctica, válida, confiable y costo-efectiva. Objetivo: Caracterizar las técnicas que miden el nivel de actividad física de cuestionarios validados por sensores de movimiento y que resulten aplicables en la población cubana. Métodos: La búsqueda se efectuó a través de bases de datos PubMed, Cochrane, LILACS y SciELO. Las palabras utilizadas en la búsqueda fueron: actividad física, actividad física/técnicas de medición, actividad física/cuestionario, inactividad física y enfermedades no transmisibles. Se consultaron documentos que hubiesen sido publicados en el periodo 2014-2019. Análisis e integración de la información: Se identificaron 66 artículos, de los cuales se seleccionaron 36 que contribuyeron al resultado final. Se describieron las características más relevantes de cada técnica, así como también las semejanzas y diferencias entre ellas. Basado en los criterios de los autores referidos y el de los autores, se definió cuál sería la técnica apropiada a utilizar. Conclusiones: Se considera que los podómetros junto con la versión corta del Cuestionario Internacional de Actividad Física (IPAQ, siglas en inglés), son las técnicas que pueden utilizarse para medir el nivel de actividad física en la población cubana(AU)


Introduction: Epidemiological studies about non-communicable diseases in Cuba require techniques that determine physical activity levels in a practical, valid, reliable and cost-effective manner. Objective: Characterize the techniques that measure the level of physical activity of questionnaires validated by movement sensors and that are applicable in the Cuban population. Methods: A search was conducted in the databases PubMed, Cochrane, LILACS and SciELO, using the descriptors physical activity, physical activity / measurement techniques, physical activity / questionnaire, physical inactivity and non-communicable diseases. The documents consulted had been published in the period 2014-2019. Data analysis and integration: A total 66 articles were identified, of which 36 were selected that contributed to the final result. A description was performed of the most relevant characteristics of each technique, as well as the similarities and differences between them. Determination was made of the appropriate technique to be used, based on criteria issued by article authors and referred authors. Conclusions: Pedometers and the short International Physical Activity Questionnaire (IPAQ) were selected as the techniques to be used to measure physical activity levels in the Cuban population(AU)


Asunto(s)
Ejercicio Físico , Técnicas de Ejercicio con Movimientos/métodos , Conducta Sedentaria , Enfermedades no Transmisibles/epidemiología , Población , Encuestas y Cuestionarios
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