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2021 ◽  
Author(s):  
Laetitia Le ◽  
Justine Touchard ◽  
Aymeric Chastel ◽  
Judith Pineau ◽  
Nicolas Martelli ◽  
...  

Abstract Background In 2020, the first mRNA COVID vaccine was approved by the with six doses from single vial. In the context of material shortages, the aim of the study was to compare different protocols to extract doses using uncrimped materials with good trueness and reproducibility. Methods To optimize the extraction of the sixth dose from a single vial with uncrimped materials, alternative protocols of preparation were tested, derived from the drug information. Results The repeatability of injected volume was acceptable for all protocols (CV<5.3%). To prepare six 0.3mL doses using uncrimped materials, protocols with an air bubble were evaluated to offset the high dead volume inherent to uncrimped materials. Regarding the limited doses observed using long intramuscular needle (92.8% of the reference dose), the air bubble protocol with a liquid volume adjustment at 0.27mL was finally validated to respect the administration of full doses. Conclusion Results highlighted the necessity to adapt the drug information protocol for the preparation and administration of Cominarty®, due to the use of high dead volume materials. Despite the good reproducibility and accuracy of the air bubble protocols, some precautions have therefore to be taken to maintain the integrity of the vaccine suspension for efficient administration.


Author(s):  
Lixue Kuang ◽  
Guofeng Xu ◽  
Yao Tong ◽  
Haifei Li ◽  
Jianyi Zhang ◽  
...  

The presence of pesticide residues in fruit has been of extensive concern worldwide. In this paper, pesticide residues in litchi samples in China and their dietary exposure risks were evaluated. Fifty-seven pesticides in 150 litchi samples were measured by GC and UPLC/MS-MS. Seventeen different pesticides were detected and 70.7% of samples contained one or more pesticide residues. The most frequently detected pesticide was diflubenzuron with a detection rate of 36%. Only carbofuran  in one sample exceeded its MRL and the exceedance was 125%. In dietary exposure assessments, all the values below LOD were calculated as 0, 1/2 LOD and LOD separately and the results demonstrated that the chronic dietary risks were extremely low. Acute exposure to carbofurn was 11.08% of the acute reference dose and acute exposure to all other pesticides was below 2% of the acute reference dose. The findings indicated that the occurrence of pesticide residues in litchis should not be considered a public health problem.


2021 ◽  
Vol 11 ◽  
Author(s):  
Xiangyu Ma ◽  
Xinyuan Chen ◽  
Jingwen Li ◽  
Yu Wang ◽  
Kuo Men ◽  
...  

BackgroundRadical radiotherapy is the main treatment modality for early and locally advanced nasopharyngeal carcinoma (NPC). Magnetic resonance imaging (MRI) has the advantages of no ionizing radiation and high soft-tissue resolution compared to computed tomography (CT), but it does not provide electron density (ED) information for radiotherapy planning. Therefore, in this study, we developed a pseudo-CT (pCT) generation method to provide necessary ED information for MRI-only planning in NPC radiotherapy.MethodsTwenty patients with early-stage NPC who received radiotherapy in our hospital were investigated. First, 1433 sets of paired T1 weighted magnetic resonance (MR) simulation images and CT simulation images were rigidly registered and preprocessed. A 16-layer U-Net was used to train the pCT generative model and a “pix2pix” generative adversarial network (GAN) was also trained to compare with the pure U-Net regrading pCT quality. Second, the contours of all target volumes and organs at risk in the original CT were transferred to the pCT for planning, and the beams were copied back to the original CT for reference dose calculation. Finally, the dose distribution calculated on the pCT was compared with the reference dose distribution through gamma analysis and dose-volume indices.ResultsThe average time for pCT generation for each patient was 7.90 ± 0.47 seconds. The average mean (absolute) error was −9.3 ± 16.9 HU (102.6 ± 11.4 HU), and the mean-root-square error was 209.8 ± 22.6 HU. There was no significant difference between the pCT quality of pix2pix GAN and that of pure U-Net (p &gt; 0.05). The dose distribution on the pCT was highly consistent with that on the original CT. The mean gamma pass rate (2 mm/3%, 10% low dose threshold) was 99.1% ± 0.3%, and the mean absolute difference of nasopharyngeal PGTV D99% and PTV V95% were 0.4% ± 0.2% and 0.1% ± 0.1%.ConclusionThe proposed deep learning model can accurately predict CT from MRI, and the generated pCT can be employed in precise dose calculations. It is of great significance to realize MRI-only planning in NPC radiotherapy, which can improve structure delineation and considerably reduce additional imaging dose, especially when an MR-guided linear accelerator is adopted for treatment.


2021 ◽  
Vol 29 (1) ◽  
Author(s):  
Klaus Doktor ◽  
Maria Lind Vilholm ◽  
Aldis Hardardóttir ◽  
Henrik Wulff Christensen ◽  
Jens Lauritsen

Abstract Background The Commission of the European Communities (CEC) has published: European Guidelines on Quality Criteria for Diagnostic Radiographic Images. These guidelines are considered a gold standard, recommended for use in quality assurance protocols. The objectives of this study: 1) Propose a graded classification format for Danish chiropractic clinics according to the CEC-quality criteria for diagnostic radiographic images of the lumbar spine. 2) Propose a reporting principle for quality of radiographic images. 3) Document variation in radiation exposure among clinics. Methods This is a cross-sectional study of image quality based on random sampling from 148 chiropractic clinics. Clinics were included if using: 1) Digital radiography and 2) The chiropractic picture and archiving system (KirPACS) at the Nordic Institute of Chiropractic and Clinical Biomechanics (NIKKB) in Denmark. A sample of 296 lumbar spine series were randomly collected from KirPACS (January 2018). Two independent observers reviewed 50 lumbar spine series twice with a 4-week interval, testing intra- and inter-observer reproducibility. The same observers then reviewed the remaining 246 radiographic studies. All studies were evaluated using the CEC Quality Criteria. Patient radiation dose values were retrieved from KirPACS (First quarter of 2020). Results A reporting and classification principle of diagnostic image quality was used in 148 chiropractic clinics. Compliance with the 22 CEC Quality Criteria had proportions ranging from 0.72–0.96 for 18 criteria, while 4 criteria specifying detail and definition ranged between 0.20–0.66. The proposed rating system (A to E) revealed: 18 A clinics, 28 B clinics, 32 C clinics, 25 D clinics and 45 E clinics (A = highest quality; E = lowest quality). The patient radiation reference dose in Denmark is 7 mGy for the AP/PA lumbar spine. Very few clinics exceed the reference dose value, approximately 50% of clinics were below 5 mGy. Conclusion A reporting principle is proposed for a graded classification format based on the CEC-quality criteria for diagnostic radiographic images of the lumbar spine. The Quality Criteria are for the most part met satisfactorily in 148 Danish chiropractic clinics, but important image details are compromised, in most cases, because of low patient radiation doses. The results of a patient radiation dose survey enabled documentation of variation in radiation exposure among chiropractic clinics.


Author(s):  
Zelenkin Sergey Evgen’evich ◽  
Karnazhitskaya Tatyana Dmitrievna ◽  
◽  

Phthalates, or phthalic acid ethers, are hazardous for human health as they produce negative&nbsp;effects on the endocrine system and liver when entering a body. Alimentary introduction into a&nbsp;body with food products is a priority for phthalates. Phthalates contents in milk are of particular&nbsp;interest since milk is the most popular food product among the population. It is vital to assess&nbsp;whether phthalates consumption from milk is safe for people due to their potential contents&nbsp;in this product and their potential hazards for human health. Research results indicate that&nbsp;when phthalates are introduced with milk it creates unacceptable non-carcinogenic risks for the&nbsp;examined children. Assessment of hazards caused by phthalates introduction allowed revealing&nbsp;that calculated phthalates doses were not safe as per adherence to the reference dose both for&nbsp;children and examined adults. The carcinogenic risk was also estimated as unacceptable both&nbsp;for children and adults.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 528
Author(s):  
Inês Neves ◽  
Maria D. Auxtero

Extemporaneous suspensions are often marketed with several administration devices that can be freely used by patients/caregivers. The homogeneity of suspensions requires shaking before use. Hence, it is crucial to assess the precision of all devices and the users’ awareness of the shaking procedure. This study was conducted at University Institute Egas Moniz with 40 pharmacy students who were asked to measure 2.5 and 5 mL of two extemporaneous azithromycin suspensions. Formulation A is marketed with a double-dosing spoon and oral syringe, whereas B includes a transparent dosing spoon. Both have a reconstitution cup. The user’s preference for administration devices, the degree of compliance with the ‘shake before use’ instruction and the accuracy of the manipulation were assessed. The double-dosing spoon was the preferred device. The “shake before use” instruction was overlooked by most volunteers. The average measured volumes obtained with the double-dosing spoon were significantly different from the ones obtained with the oral syringe (p < 0.001) and significantly lower than the reference dose (p < 0.001). The oral syringe originates significantly higher values than the reference dose (p < 0.001). The dosing spoons values were significantly different from each other (p < 0.001). Liquid medicines containing several administration devices may be a challenge since they are nonequivalent.


Author(s):  
Steve L. Taylor ◽  
Geert F. Houben ◽  
W.Marty Blom ◽  
Joost Westerhout ◽  
Benjamin C. Remington ◽  
...  

2021 ◽  
Author(s):  
Klaus Knarberg Doktor ◽  
Maria Lind Vilholm ◽  
Aldis Hardardóttir ◽  
Henrik Wulff Christensen ◽  
Jens Lauritsen

Abstract BackgroundThe Commission of the European Communities (CEC) has published: European Guidelines on Quality Criteria for Diagnostic Radiographic Images. These guidelines are considered a gold standard, recommended for use in quality assurance protocols. The objectives of this study: 1) Propose a graded classification format for Danish chiropractic clinics according to the CEC-quality criteria for diagnostic radiographic images of the lumbar spine. 2) Propose a reporting principle for quality of radiographic images. 3) Document variation in radiation exposure among clinics.MethodsThis is a cross-sectional study of image quality based on random sampling from 148 chiropractic clinics. Clinics were included if using: 1) Digital radiography and 2) The chiropractic picture and achieving system(KirPACS) at the Nordic Institute of Chiropractic and Clinical Biomechanics(NIKKB) in Denmark. A sample of 296 lumbar spine series were randomly collected from KirPACS. Two independent observers reviewed 50 lumbar spine series twice with a 4-week interval, testing intra- and inter-observer reproducibility. The same observers then reviewed the remaining 246 radiographic studies. All studies were evaluated up against the CEC Quality Criteria. Patient radiation dose values were retrieved from KirPACS. ResultsA reporting and classification principle of diagnostic image quality was used in 148 chiropractic clinics. Compliance with the 22 CEC Quality Criteria had proportions ranging from 0.72-0.96 for 18 criteria, while 4 criteria specifying detail and definition ranged between 0.20-0.66. The proposed rating system (A to E) revealed: 18 A clinics, 28 B clinics, 32 C clinics, 25 D clinics and 45 E clinics (A = highest quality; E= lowest quality). The patient radiation reference dose in Denmark is 7 mGy for the AP/PA lumbar spine. Very few clinics exceed the reference dose value, approximately 50 % of clinics were below 5 mGy.ConclusionA reporting principle is proposed for a graded classification format based on the CEC-quality criteria for diagnostic radiographic images of the lumbar spine. The Quality Criteria are for the most part met satisfactory in 148 Danish chiropractic clinics, but important image details are compromised, in most cases, because of low patient radiation doses. The results of a patient radiation dose survey enabled documentation of variation in radiation exposure among chiropractic clinics.


2020 ◽  
Vol 8 ◽  
Author(s):  
Ghazi A. Alsbeih ◽  
Khaled S. Al-Hadyan ◽  
Najla M. Al-Harbi ◽  
Sara S. Bin Judia ◽  
Belal A. Moftah

In cases of nuclear and radiological accidents, public health and emergency response need to assess the magnitude of radiation exposure regardless of whether they arise from disaster, negligence, or deliberate act. Here we report the establishment of a national reference dose–response calibration curve (DRCC) for dicentric chromosome (DC), prerequisite to assess radiation doses received in accidental exposures. Peripheral blood samples were collected from 10 volunteers (aged 20–40 years, median = 29 years) of both sexes (three females and seven males). Blood samples, cytogenetic preparation, and analysis followed the International Atomic Energy Agency EPR-Biodosimetry 2011 report. Irradiations were performed using 320 kVp X-rays. Metafer system was used for automated and assisted (elimination of false-positives and inclusion of true-positives) metaphases findings and DC scoring. DC yields were fit to a linear–quadratic model. Results of the assisted DRCC showed some variations among individuals that were not statistically significant (homogeneity test, P = 0.66). There was no effect of age or sex (P &gt; 0.05). To obtain representative national DRCC, data of all volunteers were pooled together and analyzed. The fitted parameters of the radiation-induced DC curve were as follows: Y = 0.0020 (±0.0002) + 0.0369 (±0.0019) *D + 0.0689 (±0.0009) *D2. The high significance of the fitted coefficients (z-test, P &lt; 0.0001), along with the close to 1.0 p-value of the Poisson-based goodness of fit (χ2 = 3.51, degrees of freedom = 7, P = 0.83), indicated excellent fitting with no trend toward lack of fit. The curve was in the middle range of DRCCs published in other populations. The automated DRCC over and under estimated DCs at low (&lt;1 Gy) and high (&gt;2 Gy) doses, respectively, with a significant lack of goodness of fit (P &lt; 0.0001). In conclusion, we have established the reference DRCC for DCs induced by 320 kVp X-rays. There was no effect of age or sex in this cohort of 10 young adults. Although the calibration curve obtained by the automated (unsupervised) scoring misrepresented dicentric yields at low and high doses, it can potentially be useful for triage mode to segregate between false-positive and near 2-Gy exposures from seriously irradiated individuals who require hospitalization.


2020 ◽  
Vol 206 ◽  
pp. 111398
Author(s):  
Mengcong Li ◽  
Xiaona Gao ◽  
Lei Tan ◽  
Yufan Miao ◽  
Wentao Fan ◽  
...  

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