1.Mechanism of effect of rosiglitazone on pancreatic cancer in diabetic mice based on impact of PPARy on glucose transport and metabolism
Rui-Ping HU ; Li-Feng SHANG ; He-Jing WANG ; Hong-Xia CHE ; Ming-Liang WANG ; Huan YANG ; Yuan-Yuan JIN ; Fei-Fei ZHANG ; Jian-Ling ZHANG
Chinese Pharmacological Bulletin 2024;40(7):1325-1334
Aim To explore the mechanism of the effect of rosiglitazone(Rsg)on the pancreatic cancer in diabetic mice based on the impact of PPARγ on glu-cose transport and metabolism.Methods A high-fat and high sugar diet combined with STZ was used to construct T2DM model;T2DM mice and normal mice were subcutaneously injected with PANC02 cells to construct a transplanted tumor model.T2DM trans-planted tumor mice and normal transplanted tumor mice were divided into the following groups:Rsg,PPARy inhibitor(PIN-2),rosiglitazone+PPARγ in-hibitor(Rsg+PIN-2),and normal transplanted tumor mice(NDM)and T2DM transplanted tumor mice(DM)were used as control groups,respectively.Tis-sue samples were collected after intervention.Tissue pathological changes were observed by HE staining.The expressions of Ki67 and PCNA proteins were de-tected by immunohistochemistry.Cell apoptosis was detected by TUNEL assay.The expression of PPARγwas detected by immunofluorescence.The expressions of Glucokinase,GLUT2,Nkx6.1,PDX-1RT-PCR were determined by Western blot.Results Rsg could significantly reduce the tumor mass,pathological chan-ges,Ki67 and PCNA expression of transplanted tumors(P<0.05),increase cell apoptosis and the expression of PPARγ,Glucokinase,GLUT2,Nkx6.1,PDX-1 proteins in NDM and DM mice(P<0.05).PIN-2 could reverse the indicator changes caused by Rsg in NDM and DM mice.However,compared with NDM mice,the above related indicators of the DM group mice were more sensitive to Rsg and PIN-2.Conclu-sions Compared to non-diabetic pancreatic cancer,rosiglitazone can more sensitively inhibit the prolifera-tion of pancreatic cancer with T2DM,induce apopto-sis,and reprogram the metabolism of pancreatic cancer with T2DM by activating PPA Rγ and altering the ex-pression of glucose and lipid metabolism genes,there-by exerting an anti-cancer effect.
2.Incidence of extrauterine growth retardation and its risk factors in very preterm infants during hospitalization: a multicenter prospective study.
Wei SHEN ; Zhi ZHENG ; Xin-Zhu LIN ; Fan WU ; Qian-Xin TIAN ; Qi-Liang CUI ; Yuan YUAN ; Ling REN ; Jian MAO ; Bi-Zhen SHI ; Yu-Mei WANG ; Ling LIU ; Jing-Hui ZHANG ; Yan-Mei CHANG ; Xiao-Mei TONG ; Yan ZHU ; Rong ZHANG ; Xiu-Zhen YE ; Jing-Jing ZOU ; Huai-Yu LI ; Bao-Yin ZHAO ; Yin-Ping QIU ; Shu-Hua LIU ; Li MA ; Ying XU ; Rui CHENG ; Wen-Li ZHOU ; Hui WU ; Zhi-Yong LIU ; Dong-Mei CHEN ; Jin-Zhi GAO ; Jing LIU ; Ling CHEN ; Cong LI ; Chun-Yan YANG ; Ping XU ; Ya-Yu ZHANG ; Si-Le HU ; Hua MEI ; Zu-Ming YANG ; Zong-Tai FENG ; San-Nan WANG ; Er-Yan MENG ; Li-Hong SHANG ; Fa-Lin XU ; Shao-Ping OU ; Rong JU
Chinese Journal of Contemporary Pediatrics 2022;24(2):132-140
OBJECTIVES:
To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China.
METHODS:
A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined.
RESULTS:
The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05).
CONCLUSIONS
It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.
Female
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Fetal Growth Retardation
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Gestational Age
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Hospitalization
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Humans
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Incidence
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Infant
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Infant, Newborn
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Infant, Premature
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Infant, Very Low Birth Weight
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Prospective Studies
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Risk Factors
3.Risk factors of bronchopulmonary dysplasia in very preterm infants: a national multicenter study
Ruihua BA ; Lixia TANG ; Wei SHEN ; Lian WANG ; Zhi ZHENG ; Xinzhu LIN ; Fan WU ; Qianxin TIAN ; Qiliang CUI ; Yuan YUAN ; Ling REN ; Jian MAO ; Yumei WANG ; Bizhen SHI ; Ling LIU ; Jinghui ZHANG ; Yanmei CHANG ; Xiaomei TONG ; Yan ZHU ; Rong ZHANG ; Xiuzhen YE ; Jingjing ZOU ; Huaiyu LI ; Baoyin ZHAO ; Yinping QIU ; Shuhua LIU ; Li MA ; Ying XU ; Rui CHENG ; Wenli ZHOU ; Hui WU ; Zhiyong LIU ; Dongmei CHEN ; Jinzhi GAO ; Jing LIU ; Ling CHEN ; Cong LI ; Chunyan YANG ; Ping XU ; Yayu ZHANG ; Sile HU ; Hua MEI ; Zuming YANG ; Zongtai FENG ; Sannan WANG ; Eryan MENG ; Lihong SHANG ; Falin XU ; Shaoping OU ; Rong JU
Chinese Pediatric Emergency Medicine 2022;29(6):433-439
Objective:To analyze the risk factors of bronchopulmonary dysplasia(BPD)in very preterm infants(VPI), and to provide scientific basis for the prevention and treatment of BPD in VPI.Methods:A prospective multicenter study was designed to collect the clinical data of VPI in department of neonatology of 28 hospitals in 7 regions from September 2019 to December 2020.According to the continuous oxygen dependence at 28 days after birth, VPI were divided into non BPD group and BPD group, and the risk factors of BPD in VPI were analyzed.Results:A total of 2 514 cases of VPI including 1 364 cases without BPD and 1 150 cases with BPD were enrolled.The incidence of BPD was 45.7%.The smaller the gestational age and weight, the higher the incidence of BPD( P<0.001). Compared with non BPD group, the average birth age, weight and cesarean section rate in BPD group were lower, and the incidence of male infants, small for gestational age and 5-minute apgar score≤7 were higher( P<0.01). In BPD group, the incidences of neonatal respiratory distress syndrome(NRDS), hemodynamically significant patent ductus arteriosus, retinopathy of prematurity, feeding intolerance, extrauterine growth restriction, grade Ⅲ~Ⅳ intracranial hemorrhage, anemia, early-onset and late-onset sepsis, nosocomial infection, parenteral nutrition-associated cholestasis were higher( P<0.05), the use of pulmonary surfactant(PS), postnatal hormone exposure, anemia and blood transfusion were also higher, and the time of invasive and non-invasive mechanical ventilation, oxygen use and total hospital stay were longer( P<0.001). The time of starting enteral nutrition, cumulative fasting days, days of reaching total enteral nutrition, days of continuous parenteral nutrition, days of reaching 110 kcal/(kg·d) total calorie, days of reaching 110 kcal/(kg·d) oral calorie were longer and the breastfeeding rate was lower in BPD group than those in non BPD group( P<0.001). The cumulative doses of amino acid and fat emulsion during the first week of hospitalization were higher in BPD group( P<0.001). Multivariate Logistic regression analysis showed that NRDS, invasive mechanical ventilation, age of reaching total enteral nutrition, anemia and blood transfusion were the independent risk factors for BPD in VPI, and older gestational age was the protective factor for BPD. Conclusion:Strengthening perinatal management, avoiding premature delivery and severe NRDS, shortening the time of invasive mechanical ventilation, paying attention to enteral nutrition management, reaching whole intestinal feeding as soon as possible, and strictly mastering the indications of blood transfusion are very important to reduce the incidence of BPD in VPI.
4.Generation and characterization of Cyp4v3 gene knockout mice.
Rui Xuan JIA ; Shang Wei JIANG ; Lin ZHAO ; Li Ping YANG
Journal of Peking University(Health Sciences) 2021;53(6):1099-1106
OBJECTIVE:
Bietti crystalline dystrophy (BCD) is a rare degenerative eye disease caused by mutations in the CYP4V2 gene, and Cyp4v3 is the murine ortholog to CYP4V2. To better understand the molecular pathogenesis of this disease and to explore the potential treatment we have established a Cyp4v3 knock-out mouse model.
METHODS:
Cyp4v3-/- mice were generated by clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 in embryonic stem cells of C57BL/6J mice. Ocular morphologic characteristics were evaluated via fundus imaging, histologic analysis of rods and cones via immunofluorescence, and phalloidin stain to observe retinal pigment epithelium (RPE) in whole-mounts, electroretinogram (ERG) was also conducted to examine the retinal function.
RESULTS:
The characteristic features of BCD recurred in the Cyp4v3-/- mice, including retinal crystalline deposits, atrophy and degeneration of RPE cells, and ERG amplitude decline of dark and light adapted a- and b- wave; however, the immunofluorescence stain of rod and cone cells did not show obvious differences when compared with the wild type (WT) mice. In the early stage of the disease, no crystal-like deposits were found in the fundus, ERG detection of the retinal function did not find a significant decline, and the morphological structure and quantity of the neural retina and RPE did not change significantly. Crystalline deposits occurred and converged when the Cyp4v3-/- mice at the end of 6 months, and the deposits disappeared when the Cyp4v3-/- mice at the end of 12 months. The ERG amplitude started to decline when the Cyp4v3-/- mice at the end of 6 months and deteriorated at the end of 12 months. The RPE cells of the 12-month old Cyp4v3-/- mice showed irregular shape by phalloidin staining of F-actin. The Cyp4v3-/- mice behaved normally and were viable and fertile when maintained under specific pathogen-free (SPF) housing conditions.
CONCLUSION
Just like BCD patients, the disease progress of Cyp4v3-/- mouse is correlated with the age, which provides a good model for pathogenesis and gene therapy study in the future. The atrophy and degeneration of RPE take the lead in progressing of the disease, but the mechanism is not clear yet.
Animals
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Face
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Fertility
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Gene Knockout Techniques
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Housing Quality
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Humans
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Mice
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Mice, Inbred C57BL
5.Inhibitory Effects of Agaricus Blazei Murrill (FA-2-b-β) on Proliferation of Chronic Myeloid Leukemia Cells in vivo and Its Mechanism.
Ming-Xia CHENG ; Shang-Rui YU ; Zhan-Dong WANG ; Kun-Tian BAI ; Dong-Ping WANG ; Juan LI ; Shi-Dong LIU ; Yan-Qing SUN ; Li DONG
Journal of Experimental Hematology 2020;28(6):1885-1891
OBJECTIVE:
To investigated the anti-tumor in vivo effect and mechanism of the acid RNA protein complex (FA-2-b-β) of Agaricus blazei Murrill extract.
METHODS:
CCK-8 method was used to detected the inhibitory effect of FA-2-b-β on proliferation of primary CML cells from newly diagnosed CML patients, the CML mouse model was established by trail-venous injection of primary CML cells, and the survival time, blood cell count and body weight were observed, the immunoflouresence and immunehistochemistry analysis, RT-qPCR, Western bolt were used to detemine the expression of caspase-3 signal pathway-related apoptosis genes and proteins.
RESULTS:
The experiments in vitro showed that the proliferative inhibitory rate in drug-treated group increased with concentration- and time-dependent manner (r
CONCLUSION
The FA-2-b-β can induce apoptosis of primary CML cells and prolong the survival time of CML model mouse, which may be related with the caspase-3 signal pathway related genes and proteins.
Agaricus
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Animals
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Apoptosis
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Cell Proliferation
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Humans
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Imatinib Mesylate
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K562 Cells
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Leukemia, Myelogenous, Chronic, BCR-ABL Positive
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Mice
6.Efficacy of Moxifloxacin against in Zebrafish Model .
Wen Juan NIE ; Zhong Yao XIE ; Shan GAO ; Tian Lu TENG ; Wen Qiang ZHOU ; Yuan Yuan SHANG ; Wei JING ; Wen Hui SHI ; Qing Feng WANG ; Xue Rui HUANG ; Bao Yun CAI ; Jun WANG ; Jing WANG ; Ru GUO ; Qi Ping GE ; Li Hui NIE ; Xi Qin HAN ; Ya Dong DU ; Nai Hui CHU
Biomedical and Environmental Sciences 2020;33(5):350-358
Objective:
Moxifloxacin (MFX) shows good activity against and can be a possible antibiotic therapy to treat infection; however, other studies have shown a lower or no activity. We aimed to evaluate MFX activity against using zebrafish (ZF) model .
Methods:
A formulation of labeled with CM-Dil was micro-injected into ZF. Survival curves were determined by recording dead ZF every day. ZF were lysed, and colony-forming units (CFUs) were enumerated. Bacteria dissemination and fluorescence intensity in ZF were analyzed. Inhibition rates of MFX and azithromycin (AZM, positive control) were determined and compared.
Results:
Significantly increased survival rate was observed with different AZM concentrations. However, increasing MFX concentration did not result in a significant decrease in ZF survival curve. No significant differences in bacterial burdens by CFU loads were observed between AZM and MFX groups at various concentrations. Bacterial fluorescence intensity in ZF was significantly correlated with AZM concentration. However, with increasing MFX concentration, fluorescence intensity decreased slightly when observed under fluorescence microscope. Transferring rates at various concentrations were comparable between the MFX and AZM groups, with no significant difference.
Conclusion
MFX showed limited efficacy against using ZF model. Its activity needs to be confirmed.
Animals
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Anti-Bacterial Agents
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pharmacology
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Disease Models, Animal
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Moxifloxacin
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pharmacology
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Mycobacterium Infections, Nontuberculous
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drug therapy
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Mycobacterium abscessus
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drug effects
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Zebrafish
7.Whether Syndrome Differentiation Affects Treatment Result: Study Protocol of MaZiRenWan () for Functional Constipation in A Randomized Controlled Trial.
Chung-Wah CHENG ; Li ZHANG ; Chen ZHAO ; Linda Ld ZHONG ; Li-Jie SHI ; Liang DAI ; Rui ZHENG ; Jing CHEN ; Ge LI ; Jing-Bo ZHAI ; Wai KUN ; Ai-Ping LU ; Hong-Cai SHANG ; Zhao-Xiang BIAN
Chinese journal of integrative medicine 2019;25(3):175-181
BACKGROUND:
Syndrome is one of the most important concepts in Chinese medicine (CM) theory. However, it was not well accounted in most of randomized controlled trials (RCTs).
OBJECTIVES:
To determine whether CM syndrome differentiation affects the treatment results, functional constipation (FC) was selected as a target disease, and MaZiRenWan (, MZRW), a classic CM formula commonly used for constipation with excessive heat syndrome, was selected for study.
METHODS:
It is an 18-week prospective double-blinded, doubledummy RCT, including 2-week run-in, 8-week treatment and 8-week post treatment follow-up. A total of 120 FC patients diagnosed as excessive heat syndrome will be recruited from the First Teaching Hospital of Tianjin University of Traditional Chinese Medicine and the Baokang Affiliated Hospital of Tianjin University of Traditional Chinese Medicine. Patients will be randomly allocated into fixed MZRW (f_MZRW) granule group, modified MZRW (m_MZRW) granule group or bisacodyl group. For m_MZRW group, no more than two herbal granules can be added according to the syndrome differentiation for individual participants. The primary end point is the mean of complete spontaneous bowel movements (CSBMs) per week during the treatment period. Secondary end points include mean of CSBMs per week during follow-up, stool form, global symptom improvement, constipation and constipation-related symptoms assessment, CM syndrome change, and reported adverse events.
DISCUSSION
This trial is designed to evaluate the effectiveness of these three interventions for FC patients with the CM syndrome of excessive heat, and to determine the change of CM syndrome and the progress of disease during the treatment course. The results are important to explore whether syndrome differentiation is important for the therapeutic effect of a formula on a disease. [Trial registration: Chinese Clinical Trial Registry (Reg No. ChiCTR-TRC-13003742); protocol version: MZRW/NSFC-81173363 (2015.05.04)].
Constipation
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diagnosis
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drug therapy
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Double-Blind Method
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Drugs, Chinese Herbal
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therapeutic use
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Humans
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Medicine, Chinese Traditional
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Outcome Assessment (Health Care)
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Prospective Studies
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Randomized Controlled Trials as Topic
8.Clinical value of serum neuroglobin in evaluating hypoglycemic brain injury in neonates.
Feng-Yuan JIANG ; Hui-Ping LIU ; Li-Ting CHEN ; Zhong-Rui SONG ; Shang XU ; Yu-Xiu GUO ; Lin ZHOU ; Yu-Kun WANG ; Gui-Hua SHU
Chinese Journal of Contemporary Pediatrics 2019;21(6):573-579
OBJECTIVE:
To study the clinical value of serum neuroglobin in evaluating hypoglycemic brain injury in neonates.
METHODS:
A total of 100 neonates with hypoglycemia were enrolled as subjects. According to amplitude-integrated EEG (aEEG) findings and/or clinical manifestations, they were divided into symptomatic hypoglycemic brain injury group (n=22), asymptomatic hypoglycemic brain injury group (n=37) and hypoglycemic non-brain injury group (n=41). The three groups were compared in terms of blood glucose, duration of hypoglycemia, levels of neuroglobin and neuron-specific enolase (NSE), and modified aEEG score. The correlation of neuroglobin with NSE and modified aEEG score was analyzed. The receiver operating characteristic (ROC) curve was plotted.
RESULTS:
Compared with the asymptomatic hypoglycemic brain injury and hypoglycemic non-brain injury groups, the symptomatic hypoglycemic brain injury group had significantly lower blood glucose and modified aEEG score, significantly higher neuroglobin and NSE levels, and a significantly longer duration of hypoglycemia (P<0.05). Compared with the hypoglycemic non-brain injury group, the asymptomatic hypoglycemic brain injury group had significantly lower blood glucose and modified aEEG score, significantly higher neuroglobin and NSE levels, and a significantly longer duration of hypoglycemia (P<0.05). Neuroglobin was positively correlated with NSE and duration of hypoglycemia (r=0.922 and 0.929 respectively; P<0.05) and negatively correlated with blood glucose and modified aEEG score (r=-0.849 and -0.968 respectively; P<0.05). The areas under the ROC curve of neuroglobin, NSE and modified aEEG score were 0.894, 0.890 and 0.941 respectively, and neuroglobin had a sensitivity of 80.8% and a specificity of 95.8% at the optimal cut-off value of 108 mg/L.
CONCLUSIONS
Like NSE and modified aEEG score, serum neuroglobin can also be used as a specific indicator for the assessment of brain injury in neonates with hypoglycemia and has a certain value in clinical practice.
Brain Injuries
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Electroencephalography
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Humans
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Hypoglycemic Agents
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Infant, Newborn
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Neuroglobin
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blood
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Phosphopyruvate Hydratase
9.An interlaboratory comparison study on the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels.
Ya Zhen QIN ; Li Wen ZHU ; Shang LIN ; Su Xia GENG ; Sheng Wei LIU ; Hui CHENG ; Cheng Ye WU ; Min XIAO ; Xiao Qing LI ; Rui Ping HU ; Li Li WANG ; Hai Yan LIU ; Dao Xin MA ; Tao GUAN ; Yuan Xin YE ; Ting NIU ; Jian Nong CEN ; Li Sha LU ; Li SUN ; Tong Hua YANG ; Yun Gui WANG ; Tao LI ; Yue WANG ; Qing Hua LI ; Xiao Su ZHAO ; Ling Di LI ; Wen Min CHEN ; Ling Yu LONG ; Xiao Jun HUANG
Chinese Journal of Hematology 2019;40(11):889-894
Objective: To investigate the current status and real performance of the detection of RUNX1-RUNX1T1 fusion transcript levels and WT1 transcript levels in China through interlaboratory comparison. Methods: Peking University People's Hospital (PKUPH) prepared the samples for comparison. That is, the fresh RUNX1-RUNX1T1 positive (+) bone morrow nucleated cells were serially diluted with RUNX1-RUNX1T1 negative (-) nucleated cells from different patients. Totally 23 sets with 14 different samples per set were prepared. TRIzol reagent was added in each tube and thoroughly mixed with cells for homogenization. Each laboratory simultaneously tested RUNX1-RUNX1T1 and WT1 transcript levels of one set of samples by real-time quantitative PCR method. All transcript levels were reported as the percentage of RUNX1-RUNX1T1 or WT1 transcript copies/ABL copies. Spearman correlation coefficient between the reported transcript levels of each participated laboratory and those of PKUPH was calculated. Results: ①RUNX1-RUNX1T1 comparison: 9 samples were (+) and 5 were (-) , the false negative and positive rates of the 20 participated laboratories were 0 (0/180) and 5% (5/100) , respectively. The reported transcript levels of all 9 positive samples were different among laboratories. The median reported transcript levels of 9 positive samples were from 0.060% to 176.7%, which covered 3.5-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.5 to 12.3 (one result which obviously deviated from other laboratories' results was not included) , 85% (17/20) of the laboratories had correlation coefficient ≥0.98. ②WT1 comparison: The median reported transcript levels of all 14 samples were from 0.17% to 67.6%, which covered 2.6-log. The ratios of each sample's highest to the lowest reported transcript levels were from 5.3-13.7, 62% (13/21) of the laboratories had correlation coefficient ≥0.98. ③ The relative relationship of the reported RUNX1-RUNX1T1 transcript levels between the participants and PKUPH was not always consistent with that of WT1 transcript levels. Both RUNX1-RUNX1T1 and WT1 transcript levels from 2 and 7 laboratories were individually lower than and higher than those of PKUPH, whereas for the rest 11 laboratories, one transcript level was higher than and the other was lower than that of PKUPH. Conclusion: The reported RUNX1-RUNX1T1 and WT1 transcript levels were different among laboratories for the same sample. Most of the participated laboratories reported highly consistent result with that of PKUPH. The relationship between laboratories of the different transcript levels may not be the same.
China
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Core Binding Factor Alpha 2 Subunit
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Humans
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Leukemia, Myeloid, Acute
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RUNX1 Translocation Partner 1 Protein
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Real-Time Polymerase Chain Reaction
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Transcription, Genetic
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WT1 Proteins
10. Dosimetric Study of Biliary Stent Loaded with RadioactiveI Seeds.
Li-Hong YAO ; Jun-Jie WANG ; Charles SHANG ; Ping JIANG ; Lei LIN ; Hai-Tao SUN ; Lu LIU ; Hao LIU ; Di HE ; Rui-Jie YANG
Chinese Medical Journal 2017;130(9):1093-1099
BACKGROUNDA novel radioactive 125I seed-loaded biliary stent has been used for patients with malignant biliary obstruction. However, the dosimetric characteristics of the stents remain unclear. Therefore, we aimed to describe the dosimetry of the stents of different lengths - with different number as well as activities of 125I seeds.
METHODSThe radiation dosimetry of three representative radioactive stent models was evaluated using a treatment planning system (TPS), thermoluminescent dosimeter (TLD) measurements, and Monte Carlo (MC) simulations. In the process of TPS calculation and TLD measurement, two different water-equivalent phantoms were designed to obtain cumulative radial dose distribution. Calibration procedures using TLD in the designed phantom were also conducted. MC simulations were performed using the Monte Carlo N-Particle eXtended version 2.5 general purpose code to calculate the radioactive stent's three-dimensional dose rate distribution in liquid water. Analysis of covariance was used to examine the factors influencing radial dose distribution of the radioactive stent.
RESULTSThe maximum reduction in cumulative radial dose was 26% when the seed activity changed from 0.5 mCi to 0.4 mCi for the same length of radioactive stents. The TLD's dose response in the range of 0-10 mGy irradiation by 137Cs γ-ray was linear: y = 182225x - 6651.9 (R2=0.99152; y is the irradiation dose in mGy, x is the TLDs' reading in nC). When TLDs were irradiated by different energy radiation sources to a dose of 1 mGy, reading of TLDs was different. Doses at a distance of 0.1 cm from the three stents' surface simulated by MC were 79, 93, and 97 Gy.
CONCLUSIONSTPS calculation, TLD measurement, and MC simulation were performed and were found to be in good agreement. Although the whole experiment was conducted in water-equivalent phantom, data in our evaluation may provide a theoretical basis for dosimetry for the clinical application.
Brachytherapy ; methods ; Computer Simulation ; Humans ; Monte Carlo Method ; Radiometry ; methods ; Thermoluminescent Dosimetry ; methods

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