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Lukasz M. Mazur Robert Adams Prithima R. Mosaly Joseph Nuamah Karthik Adapa Lawrence B. Marks 《Practical radiation oncology》2021,11(2):e124-e133
PurposeOur purpose was to assess the effect of a combined intervention – simulation-based training supported by neurofeedback sessions – on radiation technologists’ (RTs’) workload, situation awareness, and performance during routine quality assurance and treatment delivery tasks.Methods and MaterialsAs part of a prospective institutional review board approved study, 32 RTs previously randomized to receive versus not receive simulation-based training focused on patient safety were again randomized to receive versus not receive a 3-week neurofeedback intervention (8 sessions of alpha-theta protocol) focused on stress reduction as well as conscious precision, strong focus, and ability to solve arising problems. Perceived workload was quantified using the NASA Task Load Index. Situation awareness was quantified using the situation awareness rating technique. Performance score was calculated using procedural compliance with time-out components and error detection.ResultsRTs randomized to simulation-based training followed by neurofeedback sessions demonstrated no significant changes in perceived workload or situation awareness scores, but did have better performance compared with other study groups (P < .01).ConclusionsThis finding is encouraging and provides basis for using neurofeedback as means to possibly augment performance improvements gained during simulation-based training. 相似文献
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K. Mazur‐Melewska M. Figlerowicz A. Cwalińska H. Mikoś K. Jończyk‐Potoczna M. Lewandowska‐Stachowiak W. Służewski 《Parasite immunology》2016,38(2):101-107
Toxocara spp. infestations present with a wide spectrum of symptoms, from general inflammation of internal organs with eosinophilic granuloma formulation through ocular or brain involvement. There is also an asymptomatic form. The known factors that influence the clinical form of the disease are the intensity of the infestation, the localization of the larvae, the age of the patient, the efficiency of the immune system and the history of reinfection. The aim of our study was to evaluate the production of interleukins 4 (IL‐4) and 10 (IL‐10) in children in the course of Toxocara spp. infections with hepatic involvement. The analysis of peripheral leucocytes, eosinophils, immunoglobulin E, and IL‐4 and IL‐10 concentrations presented significantly higher values in children with radiologically confirmed liver granuloma than in uncomplicated hepatomegaly. Based on statistical analysis, we confirmed the IL‐4/IL‐10 ratio variation in the analysed groups: patients with liver lesions showed a ratio of <1, while children without granulomas had a ratio of >2. The relevant analysis confirmed a positive statistical correlation in both seropositive groups for IgE and IL‐4, and only in the granuloma group for IgE and IL‐10. 相似文献
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Konrad Matyja Anna Małachowska-Jutsz Anna K. Mazur Kazimierz Grabas 《Ecotoxicology (London, England)》2016,25(5):924-939
Dehydrogenase activity is frequently used to assess the general condition of microorganisms in soil and activated sludge. Many studies have investigated the inhibition of dehydrogenase activity by various compounds, including heavy metal ions. However, the time after which the measurements are carried out is often chosen arbitrarily. Thus, it can be difficult to estimate how the toxic effects of compounds vary during the reaction and when the maximum of the effect would be reached. Hence, the aim of this study was to create simple and useful mathematical model describing changes in dehydrogenase activity during exposure to substances that inactivate enzymes. Our model is based on the Lagergrens pseudo-first-order equation, the rate of chemical reactions, enzyme activity, and inactivation and was created to describe short-term changes in dehydrogenase activity. The main assumption of our model is that toxic substances cause irreversible inactivation of enzyme units. The model is able to predict the maximum direct toxic effect (MDTE) and the time to reach this maximum (TMDTE). In order to validate our model, we present two examples: inactivation of dehydrogenase in microorganisms in soil and activated sludge. The model was applied successfully for cadmium and copper ions. Our results indicate that the predicted MDTE and TMDTE are more appropriate than EC50 and IC50 for toxicity assessments, except for long exposure times. 相似文献
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OBJECTIVE: To investigate the cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis.
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study. 相似文献
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study. 相似文献
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Intracellular distribution of differentially phosphorylated dual‐specificity tyrosine phosphorylation‐regulated kinase 1A (DYRK1A) 下载免费PDF全文
Wojciech Kaczmarski Madhabi Barua Bozena Mazur‐Kolecka Janusz Frackowiak Wieslaw Dowjat Pankaj Mehta David Bolton Yu‐Wen Hwang Ausma Rabe Giorgio Albertini Jerzy Wegiel 《Journal of neuroscience research》2014,92(2):162-173
The gene encoding dual‐specificity tyrosine phosphorylation‐regulated kinase 1A (DYRK1A) is located within the Down syndrome (DS) critical region of chromosome 21. DYRK1A interacts with a plethora of substrates in the cytosol, cytoskeleton, and nucleus. Its overexpression is a contributing factor to the developmental alterations and age‐associated pathology observed in DS. We hypothesized that the intracellular distribution of DYRK1A and cell‐compartment‐specific functions are associated with DYRK1A posttranslational modifications. Fractionation showed that, in both human and mouse brain, almost 80% of DYRK1A was associated with the cytoskeleton, and the remaining DYRK1A was present in the cytosolic and nuclear fractions. Coimmunoprecipitation revealed that DYRK1A in the brain cytoskeleton fraction forms complexes with filamentous actin, neurofilaments, and tubulin. Two‐dimensional gel analysis of the fractions revealed DYRK1A with distinct isoelectric points: 5.5–6.5 in the nucleus, 7.2–8.2 in the cytoskeleton, and 8.7 in the cytosol. Phosphate‐affinity gel electrophoresis demonstrated several bands of DYRK1A with different mobility shifts for nuclear, cytoskeletal, and cytosolic DYRK1A, indicating modification by phosphorylation. Mass spectrometry analysis disclosed one phosphorylated site in the cytosolic DYRK1A and multiple phosphorylated residues in the cytoskeletal DYRK1A, including two not previously described. This study supports the hypothesis that intracellular distribution and compartment‐specific functions of DYRK1A may depend on its phosphorylation pattern. © 2013 Wiley Periodicals, Inc. 相似文献
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