1.Estimation of patient doses in paediatric cardiovascular interventional radiology under specific exposure conditions
Xin CHEN ; Weiyuan ZHANG ; Weihai ZHUO
Chinese Journal of Radiological Medicine and Protection 2021;41(3):199-204
Objective:To estimate the organ doses and effective doses to different-age children during cardiovascular interventional radiological procedures under some specific exposure conditions, and explore the main influencing factors on the doses.Methods:Based on the paediatric reference computational phantoms recommended in the ICRP Publication 143, several specific exposure models of cardiovascular intervention were built, and the Monte Carlocook MCNPX 2.7.0, was used to calculate the organ doses and effective doses for 1-, 5-, 10- and 15-year-old children. To validate the simulation result , an experiment was implemented by putting the thermoluminescent dosimeters in a 5-y old phantom (ATOM 705-D) manufactured by the CIRS Inc. in the USA.Results:Both the height and weight of the reference children for 1-, 5- and 10-year-old provided for by Chinese national standards are nearly in consistency with those recommended by ICRP, and even for the 15-year-old, the maximum relative deviations of the height and weight are only -1.9% and -5.7%, respectively. Under the exposure condition where the focal spot to image receptor distance (SID) was 90 cm, the length of square field of view (FOV) was 30 cm with a dose area product (DAP) of 45 Gy·cm 2, the relative deviations between simulated and measured doses to main organs/tissues within the irradiation filed were within ±6.7%. Under the same exposure conditions, the younger the children, the larger the organ doses and effective doses, and the effective doses could vary by a factor of about 5 among the 4 age groups. The conversion coefficient between the organ dose and the value of DAP was not only closely related to the age of children, but also affected by the FOV. Conclusions:In combination with the paediatric reference computational phantoms and the exposure models of cardiovascular intervention, the Monte Carlo method can be used to calculate the doses to children undergoing cardiovascular interventional radiological procedures. The information on the values of DAP and FOV as well as the directions of projection are needed for more accurate estimation of the exposure doses.
2.Screen and identify of differential proteins expressed in the placenta of Down's syndrome
Liyu YAN ; Chengjuan SUN ; Xin WANG ; Yi CHEN ; Weiyuan ZHANG
Chinese Journal of Obstetrics and Gynecology 2011;46(3):161-166
Objective To discuss protein marks expressed differentially in placenta of Down's syndrome by means of proteomics. Methods We collected placenta of 18 patients(from March 2009 to December 2009 at Beijing Obstetrics and Gynecology Hospital), and divided them into two groups, one was 10 patients with fetal Down's syndrome, the other was normal pregnancies (normal chromosome) with other diseases. We separated proteins expressed in placentas of two groups by two-dimensional difference gel electrophoresis (2D-DIGE), and then analyzed the differential protein spots by software Decyder 6. 5, then,spots differentially expressed by 1.5 fold or more were analyzed by matrix assisted laser desorption ionizationtime of flight-mass spectrometry (MALDI-TOF-MS). In the end, the differential expressional levels of partially identified proteins were validated by western blot analysis. Results (1) Differential proteins of two groups protein spots of placentas separated by 2D-DIGE were analyzed by software Decyder 6. 5 (these colored lights scattered in the image were protein spots), a total of 56 spots out of 352 were differentially expressed (P<0. 05) in two groups. We analyzed 17 protein spots(12 protein spots were over-expressed and 5 protein spots were down-expressed) differentially expressed by 1.5 fold or more by MALDI-TOF-MS.(2) Protein matching after searching protein database, 17 protein spots turn out to be 10 proteins. Four kinds [superoxide dismutase 1 (SOD1), peroxiredoxin 6 (PRDX6), heat shock protein 27 (HSP27),endoplasmic reticulum protein 29 (ERP29)] of them were validated by western blot analysis, the group of fetal Down's syndrome were 0.74 ±0. 12,0.29 ±0. 10,0.53 ±0. 16,0.20 ±0. 09,the group of normal pregnancies were 0. 51 ±0. 08,0. 34 ± 0. 16,0. 18 ± 0. 07,0. 35 ± 0. 09, the results confirmed the observed changes in proteomics. Conclusions Compared with normal pregnancies, there were differential proteins expressed in placenta of Down's syndrome. This approach might provide new screening markers in use for prediction of Down's syndrome, however, further study should be done to make these 4 proteins (SOD1,HSP27, ERP29, PRDX6) be new screening markers.
3.Multiple stepwise regression analysis on postoperative knee joint function limitation in complex femoral condyles fractures
Songjun LI ; Zhaojie WANG ; Weiyuan TAN ; Lipeng KUANG ; Junping CHEN
Chinese Journal of Tissue Engineering Research 2013;(52):9029-9034
BACKGROUND:Knee joint function limitation often occurs after internal fixation of complex femoral condyle fractures, but the mechanism and its influencing factors are also unclear.
OBJECTIVE:To screen and analyze the relevant factors of knee joint function limitation after internal fixation of complex femoral condyle fractures.
METHODS:We retrospectively summarized postoperative fol ow-up data of 6 and 12 months from 121 patients with complex femoral condyle fractures. Knee joint function recovery was evaluated according to Merchan criteria. A multiple stepwise regression analysis was carried out in terms of gender, age, causes, concomitant injuries, skin and soft tissue injury, fracture type, fixed method, operation time, postoperative plaster fixed situation, healing of postoperative incision, bone healing and postoperative functional exercises, to summarize the relevant influencing factors for knee joint function limitation.
RESULTS AND CONCLUSION:Whether the knee joint function after internal fixation was limited acted as the dependent variable Y, and factors with statistical significance of the single factor analysis served as the independent variable X. We used the multiple stepwise regression analysis for multiple factors analysis. Results showed that the gender of patients (X1), with or without concomitant injuries (X3), soft tissue damage (X4) and operation time (X6), a total of four factors, could not be introduced into the model, suggesting that these four factors had no significant correlation with postoperative knee joint function limitation. Another eight factors could be introduced into the factor analysis model, showing that the cause of injury (X2), fracture type (X5), the choice of internal fixation (X7), with or without bone graft (X8), with or without postoperative plaster cast (X9), postoperative knee joint functional exercise or not (X10) and postoperative wound healing (X11), the degree of postoperative bone healing (X12) are closely related to postoperative knee joint function limitation in complex femoral condyles fractures.
4.Clinic characteristics of women with advanced maternal age and perinatal outcomes
Yu CHEN ; Xiaoli ZHENG ; Shaowen WU ; Weiyuan ZHANG
Chinese Journal of Obstetrics and Gynecology 2017;52(8):508-513
Objective To explore the association between maternal age and perinatal outcomes.Methods Totally,3 151 women with advanced maternal age and 6 098 women younger than 35 years old who delivered in Beijing Obstetrics and Gynecology Hospital in 2016 were recruited.Their clinic characteristics and perinatal outcomes were collected to divide into 3 groups based on delivery age,Group 1 (aged 35-39 years,2 683 cases),Group 2 (aged ≥40 years,366 cases) and the control group (aged<35 years,6 098 cases).The association between maternal age and adverse perinatal outcomes were analyzed,including hypertensive disorder complicating pregnancy,gestational diabetes mellitus (GDM),preterm birth and postpartum hemorrhage.Results The rate of cesarean section history (27.39%,33.61%,5.53%) or previous myomectomy history (2.80%,5.46%,0.72%) were compared between the advanced maternal age groups and the control group,and the differences were statistically significant (P<0.05).The percentage of prepregnancy overweight and obesity (29.67%,27.05%,18.47%),complicated with myoma (14.83%,19.95%,5.64%) were compared among the three groups,and the differences were statistically significant (P< 0.05).The percentage of pregnancy through assisted reproductive technology (9.84%,15.03%,3.12%) also had statistically significant differences (P<0.05).The incidence of fetal chromosomal abnormalities (1.23%,3.01%,0.36%) and fetal malformations (1.94%,4.37%,0.48%) increased with the maternal age,with statistically significant differences (P<0.01).The mobidity of hypertensive disorders (9.84%,13.11%,9.23%),pregestational diabetes mellitus (1.83%,2.19%,0.72%),gestational diabetes mellitus (22.70%,28.42%,14.87%),premature rupture of membranes (25.57%,19.40%,31.42%),placenta previa (2.05%,2.46%,0.92%),preterm birth(8.35%,11.20%,5.51%),postpartum hemorrhage (25.11%,18.31%,20.27%)and forceps delivery (5.42%,2.33%,5.71%) were compared,and the differences were statistically significant (P<0.05).The cesarean section rate in primipara (45.42%,75.74%,21.33%) and multipara (51.46%,61.54%,30.95%) had statistically significant difference (P<0.05).The proportion of macrosomia (10.80%,8.85%,7.96%) and neonates transferred into neonatal ICU (9.63%,11.48%,5.21%) in term neonates had statistically significant difference (P<0.05).Conclusions Women with advanced maternal age increase after new family planning policy put into effect,so do the risk of adverse perinatal outcomes.Attention and interventions should be made to cope with the occurrence of adverse perinatal outcomes.
5.Meta-analysis of association between periodontal disease and preeclampsia
Jingfei ZHANG ; Shasha YU ; Shengping CHEN ; Weiyuan ZHANG
Chinese Journal of Perinatal Medicine 2015;18(6):430-436
Objective To explore the relationship between periodontal disease and preeclampsia and the effects of periodontal treatment on preeclampsia.Methods China National Knowledge Infrastructure,Chinese Biomedical Literature Database,WANGFANG DATA,China Dissertation Full-Text Database,China Proceedings of Conference Full-Text Database,Cochrane Library,PubMed,EMbase,Elsevier,Springer,and Science Direct OnSite were extracted from inception till September 30,2014.The case-control,cohort and randomized controlled trials about the association of matemal periodontal disease and preeclampsia were searched according to the inclusion and exclusion criteria.RevMan5.1 and Stata12.0 were used to test the heterogeneity of the results among the different studies and amalgamate the effect size using fixed or random effect models.Results Twenty studies (15 case-control and 5 cohort) involving 8 775 women assessed the association between periodontal disease and preeclampsia.A positive association was found (OR=2.48,95%CI:1.76-3.48,P < 0.01).Meta-analysis of the case-control studies showed more than twice in the odds of preeclampsia with the presence of periodontal disease (OR=2.75,95%CI:1.93-3.92,P < 0.01).Meta-analysis of cohort studies did not reveal any significant differences (OR=1.84,95%CI:0.91-3.74,P > 0.05).Four randomized controlled trials with 3 712 women evaluated the effect of periodontal treatment on preeclampsia,and meta-analysis showed no relative risk reduction in preeclampsia with periodontal treatment (RR=1.04,95%CI:0.84-1.30,P > 0.05).Conclusions Periodontal disease appears to be a possible risk factor for preeclampsia,but treatment during pregnancy does not prevent preeclampsia.High-quality prospective studies are needed to confirm the relationship between periodontal disease and preeclampsia.
6.Evaluation on the performance of MicroScan WalkAway in detecting carbapenem-resistant Enterobacteriaceae
Zhichang ZHAO ; Maobai LIU ; Bin LI ; Weiyuan CHEN ; Jingling ZHANG ; Liya HUANG ; Rui LIU ; Qili LIN
Chinese Journal of Infection and Chemotherapy 2017;17(1):42-45
Objective To investigate the performance of MicroScan WalkAway 96 Plus (MSW) system in detection of carbapenem-resistant Enterobacteriaceae (CRE).Methods A total of 81 stock CRE strains were used in this study. Bacterial identification and antimicrobial susceptibility test were performed by MSW system. Beta-lactamases genes blaKPC,blaIMP,blaVIM, blaOXA-48 and blaNDM were amplified by PCR and subjected to sequencing analysis. Disk diffusion method and PCR were used as gold standard to evaluate the performance and reliability of MSW system in identifying carbapenem-resistant and carbapenemase-producing Enterobacteriaceae.Results Overall, 69.1 % (56/81) of the Enterobacteriaceae strains were identified as CRE by the MSW system. The results of PCR showed that 48 strains were carbapenemase-producing Enterobacteriaceae. When carbapenemase-producing Enterobacteriaceae strains were identified by the instrument using an advanced expert system, the sensitivity was 93.8 % and specificity was 42.4 %. The positive predictive value was 70.3 %, the negative predictive value was 82.4 % and the predictive accuracy value was 72.8 %.Conclusions The MicroScan WalkAway 96 Plus system has shown good performance in detection of CRE.
7.Study on the simulation training of obstetric emergency
Yi CHEN ; Ling FAN ; Cuicun HAN ; Cuimei GUO ; Xiaowei LIU ; Yan LIU ; Weiyuan ZHANG
Chinese Journal of Medical Education Research 2016;15(9):969-972
Medical simulation training as a modern medical education has been used for decades in developed countries. Simulation based team training for obstetric emergency provides opportunities to re-hearse without risks to patients and helps overcome some limitations of the current medical education to improve the ability of medical staff to deal with obstetric emergencies, and improve adverse pregnancy out-comes. Simulation training is still at early stage in China. The Simulation Training Center of Beijing Ob-stetrics&Gynecology Hospital was established in June 2013. There are 100 medical staffs from our hospital and 406 from other hospitals who are trained using simulations to respond to acute obstetrical emergencies, including postpartum hemorrhage, neonatal recovery, shoulder dystocia and amniotic fluid embolism. Through introduction—on-scene simulation training—task report, we focus on learning, practical operation, emer-gency team and multidisciplinary coordination and communication skills training and through training, help learners understand the medical simulation training mode, and improve personal and team's ability to deal with the obstetric emergency. There is no doubt that simulation training will be further developed in China. Further research is required to investigate the application significance and feasibility of simulation training and access effectiveness of it.
8.Bone cement injection as vertebral augmentation therapy for osteoporotic vertebral compression fractures
Junping CHEN ; Xinwen QI ; Songjun LI ; Lipeng KUANG ; Xiaohong YUAN ; Guoshou WANG ; Weiyuan TAN
Chinese Journal of Tissue Engineering Research 2015;19(21):3292-3296
BACKGROUND:Vertebroplasty with bone cement injection can achieve a correction of kyphosis, enhancement of vertebral strength, and elimination of vertebral lesions during reduction of the fracture. OBJECTIVE: To analyze the efficacy of vertebroplasty with bone cement injection on osteoporotic vertebral compression fracture. METHODS:Totaly 84 patients with osteoporotic thoracolumbar vertebral compression fractures (T6-L4), 37 males and 47 females, aged 58-80 years, were randomized into two groups: study group undergoing vertebroplasty with bone cement injection and control group subject to bed rest and conservative treatment (functional exercise of the back muscle). Visual analog scale score, Oswestry disability index and vertebral height were detected and compared between the two groups before and after treatment. RESULTS AND CONCLUSION:There was no difference in vertebral height, visual analog scale score and Oswestry disability index between the two groups before treatment. At 3 months after treatment, the vertebral height was (1.653±0.168) cm in the study group and (1.521±0.200) cm in the control group, with a significant difference (P< 0.05). The visual analog scale scores and Oswestry disability index scores in the study group were both lower than those in the control group at 3 months after treatment and at the last folow-up (P < 0.05). After treatment, there were two cases of pressure sores, three cases of deep venous thrombosis, one case of pneumonia and two cases of urinary tract infections in the control group; while only 4 cases developed bone cement leakage in the study group, but with no obvious clinical symptoms. No difference in re-fracture rate occurred between the control group (n=3) and study group (n=4;P > 0.05). These findings suggest that the bone cement injection as vertebral augmentation therapy can rapidly relieve pain, improve patients' quality of life within a short term and restore the vertebral height in patients with osteoporotic vertebral compression fractures.
9.Appropriate delivery mode and timing of termination for pregnancy with low birth weight infants
Yi CHEN ; Liying ZOU ; Guanghui LI ; Yan RUAN ; Xin WANG ; Weiyuan ZHANG
Chinese Journal of Obstetrics and Gynecology 2015;(5):323-328
Objectives To investigate the delivery mode and perinatal outcomes of low birth weight infants in mainland China, and to explore the appropriate delivery mode and timing of delivery. Methods Clinical data of 103 678 babies delivered from Jan 1st to Dec 31th, 2011 in 39 hospitals in mainland China were analyzed retrospectively. The 39 hospitals located in 7 administrative regions, including Northeast, Northwest, North, Central, East, South and Southwest China. Result (1) The average birth weight of the newborns was (3 263 ± 540) g. Among them, 7 474 cases were diagnosed low birth weight infants, with the incidence of 7.209%(7 474/103 678). There were 2.328%(2 214/95 116 ) full-term low birth weight infants and 61.434% (5 260/8 562 ) preterm low birth weight infants. (2) From week 28 to week 36, the cesarean section rate of low birth weight infants increased with the increasing of gestational weeks. The cesarean section rate of full-term low birth weight infants were 61.14%(1 139/1 863) , which was higher than that of normal birth weight infants (52.947%, 45 108/85 195). The differences were statistically significant (P<0.01). (3) The constitution of the indication of cesarean section showed that social factor and maternal factor were 10.73%(443/4 128) and 48.91%(2 019/4 128) for low birth weight infants, respectively. While for the normal birth weight infants, they were 27.70%(12 495/45 108) and 38.60%(17 412/45 108), respectively. There was statistically significant difference(P<0.01). (4) The emergency cesarean section rate of full-term low birth weight infants was 41.09%(468/1 139), which was higher than that of normal birth weight infants (31.09%, 14 024/45 108). The difference was statistically significant (P<0.01). (5) The rates of stillbirth, neonatal asphyxia and the mortality of full-term low birth weight infants were 2.36%(44/1 863), 6.12%(114/1 863), and 3.17%(59/1 863), respectively. Those of normal birth weight infants were 0.11%(94/85 195), 1.41%(1 201/85 195), and 0.14%(119/85 195), respectively. The differences were statistically significant (P<0.01). (6) The stillbirth rate and mortality of low birth weight infants born by cesarean delivery were significantly lower than those born by vaginal delivery. The rate of neonatal asphyxia (17.95%) and other morbidity (3.61%) among low birth weight infants born by cesarean section in week 28 to week 33+6 were significantly lower than those born by vaginal delivery (30.09%, 6.62%, respectively). (7) With the increase of gestational age, the incidence of neonatal asphyxia and stillbirth decreased. The incidence of neonatal asphyxia(39.22%) and stillbirth(23.28%) was most seen in 28 to 29 gestational weeks, which decreased to 9.08% and 2.88% in 34 gestation weeks. Conclusions Low birth weight is one of the leading causes of adverse perinatal outcomes and cesarean section. To decrease the incidence of low birth weight, individualized management should be performed according to the gestational age and fetal condition. Extending the gestational age to at least 34 weeks may avoid iatrogenic preterm labor and improve the neonatal survival rate.
10.CT-guided 125I seeds interstitial implantation for the refractory liver cancers ineffective to commonly used therapies
Jiaping ZHENG ; Guoliang SHAO ; Jun LUO ; Yutang CHEN ; Zheng YAO ; Hui ZENG ; Weiyuan HAO
Journal of Interventional Radiology 2015;(3):260-264
Objective To evaluate the safety and clinical efficacy of CT-guided 125I seeds interstitial implantation in treating the refractory liver cancers that show poor response to commonly used therapies. Methods A total of 40 patients with refractory clinically or pathologically-proved liver cancer were enrolled in this study, the diseases included primary liver cancer (n = 27, with coexisting portal vein cancerous thrombus in 2) and metastatic liver cancer (n = 13). CT-guided 125I seeds interstitial implantation was performed in all patients. Preoperative plan of seeds implantation protocol was formulated by using the treatment plan system (TPS); the 125I seed activity was 0.6 -0.8 mCi and the peripheral matching dose (MPD) was 100 -140 Gy. The procedure of 125I seeds interstitial implantation was performed under local anesthesia in all patients. By using percutaneous trans-hepatic puncturing and single-or multiple-needle technique, the 125I seeds were implanted along a line parallel to the long axis of the tumor and/or tumorous thrombus with an interval of 0.5 -1.0 cm. The short-term efficacy was evaluated by modified response evaluation criteria in solid tumors (mRECIST), and the median time to tumor progression (mTTP) and the median overall survival time (mOS) were calculated by Kaplan and Meier method. Results The technical success rate was 100%. The diameter of the tumor was 1.5 -12.0 cm (mean 4.0 cm), and a total of 1 748 125I seeds were implanted in 40 patients (mean 44 seeds per patient). The short-term effective rate was 37.5%(n = 15), including complete remission in 8 cases and partial remission in 7 cases, the stable disease was seen in 15 cases (37.5%), and the disease control rate was 75%. The mTTP was 7.0 months (95%CI:4.524-9.476 months), while mOS was 10 months (95%CI: 6.901 -13.099 months). The procedure-related adverse reactions included small amount of subcapsular hemorrhage (n =2, 5%), intrahepatic migration of 125I seeds (n=2, 5%), pain at liver area (n=1, 2.5%); and no special treatment was needed in these patients. One patient developed high fever with chills 3 hours after the procedure, which was relieved after symptomatic and antipyretic treatment. Conclusion For the treatment of refractory liver cancers, CT-guided 125I seeds permanent interstitial implantation, used as a remedial therapy, is safe and effective. This technique is worth popularizing in clinical practice.