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Objective:To analyze the clinical reliability of neonatal bedside photography protection and body position fixing device during neonatal bedside X-ray photography.Methods:A mobile X-ray diagnostic machine was used to project the phantom of children. The samples were divided into group A with conventional bedside photography mode, and group B using neonatal bedside X-ray photography protection device. X-ray diagnostic level dosimeters were placed at the projection and radiation sensitive sites, respectively. The three parts of the chest, pelvis and skull were used as the projection center, and the radiation dose to the projection site and the radiation sensitive site were collected and recorded, and the statistical analysis was carried out.Results:When the chest was taken as the center of the projection, the radiation doses to the lens of the eye, thyroid and gonad in the body model group B of children were 94.4%, 96.9% and 96.7% lower than those in the non-injected part of group A, respectively ( t=-152.55, -445.16, -129.07, P<0.05). When the pelvis was taken as the projection center, the radiation doses to the lens, thyroid and thymus in the body model group B were 85.5%, 87.1% and 94.9% lower than those in the non-projection part of group A, respectively ( t=-50.68, -194.18, -535.94, P<0.05). When the head was taken as the projection center, the radiation doses to thyroid, thymus and gonad in the body model group B were 99.3 %, 97.4 % and 94.3 % lower than those in the non-projection position of group A, respectively ( t=-1 859.97, -542.08, -66.26, P< 0.05). Conclusions:The use of neonatal bedside photography protection and position fixing device during neonatal bedside X-ray photography can significantly reduce the radiation dose to children in non-projected areas under the premise of ensuring image quality. At the same time, it can fix and protect the children, improve the success rate of examination, being worthy of clinical promotion.
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Objective:To investigate the value of the size-specific dose estimate (SSDE) on dose estimations of children's head CT scans.Methods:A retrospective study was conducted on plain head CT scans of 252 patients with the 64-row detector CT device of Discovery 750HD in the Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January to September in 2019. The volume CT dose index (CTDI vol)values were recorded. The head circumference (HC), area, and CT value were measured using a self-developed computer program, and the water equivalent diameter (WED), size-specific conversion factors ( f293 and f220), and absorbed dose (SSDE 293 and SSDE 220) were calculated according to the AAPM reports 293 and 220.The patients were divided into three groups by the quartering meth odaccording to their HC(<47.8 cm, 47.8-52.7 cm, >52.7 cm)and four groups based on their ages(0-2, 3-6, 7-10 and 11-14 years old). The difference between parameters ( f220 and f293, SSDE 220 and SSDE 293、SSDE 293 and CTDI vol) were compared for different groups, and the correlation of HC with f293 and SSDE 293 was analyzed. Results:There was an overestimation of f220 by 11.11% ( t=252.61, P<0.05) compared with f293. SSDE 220 was overestimated by 10.31% ( t=228.21, P<0.05) compared with SSDE 293, and SSDE 293 was underestimated by 9.60% ( t=-31.34, P<0.05)compared with CTDI vol. For the three HC groups, SSDE 220 was overestimated by 8.54%, 10.37%, and 11.57% ( t=73.73, 438.58, 275.52, P<0.05)compared with SSDE 293, and SSDE 293 was underestimated by 1.30%, 9.79%, and 14.61% ( t=-1.91, -60.95, -47.64, P<0.05)compared with CTDI vol. For the four age groups SSDE 220 was overestimated by 8.45%, 10.00%, 10.57%, and 11.36% ( t=63.58, 232.29, 247.84, 302.95, P< 0.05)compared with SSDE 293, and SSDE 293 was underestimated by 1.49%, 8.27%, 10.63%, and 13.78% ( t=-1.83, -28.27, -37.30, -49.80, P< 0.05)compared with CTDI vol. Furthermore, HC was highly correlated with f293 and SSDE 293 ( r2=0.88 and 0.76, respectively, P< 0.05). Conclusions:The radiation dose in children′s head CT scanning can be more accurately estimated according to the AAPM Report 293, while it can be overestimated by CTDI vol. Meanwhile, the CT radiation dose can be patently overestimated with the AAPM Report 220 compared with Report 293.HC is closely correlated with f293 and SSDE 293 and it can be used to estimatee more accurately for SSDE and the radiation dose received by children during head CT scanning.
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Objective To investigate the effect of scan table on size-specific dose estimate ( size-specific dose estimate, SSDE) in children's CT scan. Methods CT imaging data and CTDIvol of 44 children ( 15 heads, 13 chests, 16 abdomen-pelvis) who underwent Siemens SOMATOM Definition AS+ 64 row 128-slice CT scan were retrospectively collected. CTDIvol of each patient was recored, WED ( water equivalent diameter) was calculated by two different methods ( with or without table) , donated as WED-T and WED-NT, then the corresponding SSDEWED ( SSDEWED-T and SSDEWED-NT ) was calculated. And the SSDEWED-NT was used as reference to evaluate the difference between WED and SSDEWED obtained by two different methods. Results Including part of table will lead to the overestimate for WED, with mean differences of 0. 10％, 2. 82％ and 2. 54％ for head, chest and abdomen-pelvis, respectively, while SSDEWED will be underestimated by 0. 06％ ( head ) , 2. 70％ ( chest ) and 1. 59％ ( abdomen-pelvis ) . Conclusions Including par of the patient table has a certain effect on SSDEWED for children, more attention should be paid for the application of SSDEWED.
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<p><b>Background</b>MicroRNAs (miRNAs) have been reported to play vital roles in liver regeneration. Previous studies mainly focused on the functions of intracellular miRNAs, while the functions of circulating exosomal miRNAs in liver regeneration remain largely unknown. The aim of this study was to identify the key exosomal miRNA that played vital roles in liver regeneration.</p><p><b>Methods</b>The Sprague-Dawley male rats were assigned to 70% partially hepatectomized group (n = 6) and sham surgery group (n = 6). The peripheral blood of both groups was collected 24 h after surgery. The exosomal miRNAs were extracted, and microarray was used to find out the key miRNA implicated in liver regeneration. Adenovirus was used to overexpress the key miRNA in rats, and proliferating cell nuclear antigen (PCNA) staining was applied to study the effect of key miRNA overexpression on liver regeneration. Western blotting was used to validate the predicted target of the key miRNA.</p><p><b>Results</b>Exosomal miR-10a was upregulated more than nine times in hepatectomized rats. The level of miR-10a was increased in the early phase of liver regeneration, reached the top at 72 h postsurgery, and decreased to perioperative level 168 h after surgery. Moreover, enforced expression of miR-10a by adenovirus facilitated the process of liver regeneration as evidenced by immunohistochemical staining of PCNA. Erythropoietin-producing hepatocellular receptor A4 (EphA4) has been predicted to be a target of miR-10a. The protein level of EphA4 was decreased in the early phase of liver regeneration, reached the bottom at 72 h postsurgery, and rose to perioperative level 168 h after surgery, which was negatively correlated with miR-10a, confirming that EphA4 served as a downstream target of miR-10a. Moreover, inhibition of EphA4 by rhynchophylline could promote the proliferation of hepatocytes by regulating the cell cycle.</p><p><b>Conclusion</b>Exosomal miR-10a might accelerate liver regeneration through downregulation of EphA4.</p>
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OBJECTIVE@#To explore the effects of NGX6 on the transcriptional activation of beta-catenin/TCF/LEF in Wnt/beta-catenin signal pathway, and to identify the role of NGX6 in Wnt signal pathway.@*METHODS@#The eukaryotic expression vector pcDNA3.1(+)-beta-catenin (WT) was constructed. pcDNA3.1(+)-beta-catenin (WT) and pCMV-myc-NGX6 were cotransfected to COS-7 and the transcriptional activity of TCF/LEF was detected by TCF-4 luciferase report system. Without extro-genous beta-catenin, pCMV-myc-NGX6 was transfected alone to COS-7 and colon cancer cell line SW620, and the transcriptional activity of TCF/LEF was detected by TCF-4 luciferase report system, and then the expression of nucleus beta-catenin and TCF-4 was detected by Western blot.@*RESULTS@#The eukaryotic expression vector pcDNA3.1(+)-beta-catenin (WT) was successfully constructed. The activation of TCF-4 luciferase report gene in the cotransfection group in COS-7 was less than that in NGX6 alone transfection group (P<0.05). The activation of TCF-4 luciferase report gene in NGX6 alone transfection group without extro-genous beta-catenin was less than that in pCMV-myc transfection group in COS-7 and SW620. The expression of beta-catenin and TCF-4 was decreased after the NGX6 transfection in COS-7 and SW620 cells.@*CONCLUSION@#NGX6 can inhibit the transcriptional activation of beta-catenin/TCF/LEF in Wnt signal pathway by its negative regulation in the nuclear translocation of beta-catenin.