3.Mean absorbed dose calculation at cellular level for targeted radiotherapy using Auger-electron-emitters
Yunlai WANG ; Liangan ZHANG ; Guangfu DAI
Chinese Journal of Radiological Medicine and Protection 2001;21(2):76-79
Objective To calculate the mean absorbed doses at celluar and subcellular levels for uniformly and non-uniformly distributed Auger electron emitters. Methods The energy deposited in cell or nucleus by Auger electrons was analytically calculated using the polynomial representation of energy loss.S-values were subsequently computed for several target-source combinations.The absorbed dose and dose distribution were calculated for spherically symmetric radionuclide distributions depending linearly and exponentially on the radial position.The dose profile as a function of the source radial coordinate was also evaluated for typical cell sizes.The contributions of photon radiation to absorbed dose in cells were ignored. Results The mean absorbed dose and dose distribution depend largely on the size of target cells,the radiation spectrum and intracellular localization and distribution of radionuclides.The contribution of intranuclear radionuclides to mean absorbed dose was larger than that of extranuclear ones. Conclusion Auger electrons can produce high local energy deposition in cells because of their very low energies and extremely short ranges.Our dose calculation method is simple.The results are reliable and can be used in many fields.
4.The microRNA gene expression profiling in HepG2 cells transfected with full-long hepatitis B virus genome
Yan LIU ; Liang ZHANG ; Jiuzeng DAI
Medical Journal of Chinese People's Liberation Army 1983;0(02):-
Objective MicroRNA(miRNA)has recently been suggested to play a role in certain virus infections.The present study is to investigate if miRNA is associated with hepatitis B virus(HBV)activity by detecting differential expression of miRNA between human hepatoblastoma cell line HepG2.2.15 transfected with full-long HBV genome and its parent cell line HepG2.Methods Total RNA were extracted from HepG2.2.15 cells and control HepG2 cells,respectively.miRNAs were then isolated from the total RNA.Mammalian miRNA microarrays containing 509 miRNA genes were employed to analyze the differentially expressed miRNAs between the two groups.miRNAs were considered to be up-or down-regulated when the fluorescent intensity ratio between the two groups was over 4-fold and global false positive is zero using SAM program.Validation of microarray results was carried out by real-time quantitative RT-PCR(qRT-PCR).Results Compared with those of control HepG2 cells,a total of 27 miRNAs were differentially expressed(5.3% of all probes),among which 7 were up-regulated and 20 were down-regulated in HepG2.2.15 cells.qRT-PCR verified that miR-181d expression was 16-fold up-regulated and miR-15a was 9-fold down-regulated in HepG2.2.15 cells,which was in agreement with the results of the microarray analysis.Conclusion The findings suggest that there are HBV replication-associated miRNAs in HBV genome-transfected HepG2.2.15 cells.These up-and down-regulated miRNAs may be involved in the life cycle of HBV replication.The knowledge is helpful for further study to discover new molecular targets for anti-HBV therapy.
5.Effects of different doses of Xuebijing injection in treatment of ischemia reperfusion injury in rabbit limbs
Liang ZHANG ; Wei DAI ; Zhiming GAO ; Jihong ZHOU ; Dawei LIU
Chinese Journal of Trauma 2013;29(8):796-799
Objective To investigate effect and mechanism of Xuebijing administration at various concentrations on ischemia reperfusion injury (IRI) of rabbit limbs.Methods Thirty New Zealand rabbits were divided into control group (n =10),Xuebijing group Ⅰ (n =10) and Xuebijing group Ⅱ(n =10) according to random number table.Rabbit models of IRI in lower extremities were established.Each group received corresponding therapy after reperfusion:rabbits in Xuebijing group Ⅰ were firstly administered 4 ml/kg Xuebijing solution and 6 ml/kg isotonic saline; rabbits in Xuebijing group Ⅱ were administered 2 ml/kg Xuebijing solution and 8 ml/kg isotonic saline; rabbits in control group were simply administered 10 ml/kg isotonic saline.Venous blood samples were collected before reperfusion and at 1 h,2 h,4 h after reperfusion to measure coagulation parameters (APTT,Fib,INR and PT) and biochemical items (ALB,LDH and CK).Results APTT in Xuebijing group Ⅰ presented obvious improvement at 1 h and 4 h after reperfusion as compared with control group (P < 0.01).PT in Xuebijing groups Ⅰ and lⅡ was significantly longer after reperfusion than that before reperfusion (P <0.05).Fib level in Xuebijing group Ⅰ was much higher at 4 h after reperfusion than that before reperfusion (P < 0.05).ALB level at 1 hour after reperfusion showed no statistical differences from that before reperfusion in Xuebijing groups Ⅰ and Ⅱ (P > 0.05).LDH and CK levels in Xuebijing group Ⅰ were much lower than those in control group after reperfusion (P < 0.05).Conclusions Xuebijing injection relieves limb IRI,with better effect in Xuebijing group Ⅰ than in Xuebijing group Ⅱ.Therapeutic mechanism may be associated with its involvement in adjusting clotting function and mitigating injury of muscle tissues.
6.Clinical value of color Doppler ultrasound in diagnosis of acute rejection following renal transplantation
Cheng DAI ; Ping WANG ; Xintao ZHANG ; Zhiheng HUANG ; Xin LIANG
Chinese Journal of Tissue Engineering Research 2009;13(53):10427-10430
BACKGROUND: Using color Doppler ultrasonography, renal graft size, appearance, structure, and blood flow distribution can be observed. Through the use of blood flow display technique, blood flow perfusion of renal graft can be accurately observed to assist diagnosis and differential diagnosis of complications following renal transplantation. OBJECTIVE: To observe the hemodynamic characteristics during different periods of acute renal transplant rejection, summarize its specific manifestations through analyzing different reaction of two dimensional and color Doppler flow imaging (CDFI) during renal transplantation in order to get valuable index on acute rejection of renal transplantation.DESIGN, TIME AND SETTING: Comparative observation was performed at the Jinan University and First Hospital of Shenzhen University between January 2003 and January 2007.PARTICIPANTS: A total of 299 patients undergoing renal transplantation were divided into normal allograft group (n=236) and acute rejection group (n=63) according to renal allograft function.METHODS: The systolic peak flow rate, end-diastolic flow rate, mean flow rate, pulsatility index and resistance index of main renal artery and arcuate artery in patients of two groups were compared. MAIN OUTCOME MEASURES: Renal allograft arterial inner diameter and hemodynamics of two groups.RESULTS: Compared with normal allograft group, the blood flow perfusion was reduced at acute rejection, which could not reach cortex margin, blood velocity was decreased at the diastolic phase, pulsatility index and resistance index were increased (P < 0.05). CONCLUSION: Color Doppler ultrasound, as a convenient, economical and noninvasive technique, provides the reliable evidences for the renal artery pulsatility index and resistance index in clinic, and also is valuable for the acute rejection early diagnosis of renal allograft.
7.Commissioning of intensity - modulated radiation therapy system with independent collimator
Ke ZHANG ; Jianrong DAI ; Li CHEN ; Yuheng LI ; Liang LI
Chinese Journal of Radiation Oncology 2011;20(2):164-167
Objective To perform an acceptance test for the IMRT system with independent collimator. Methods An ion chamber dosimeter were used to measure the startup characteristics of the accelerator and the absolute dose at isocenter and given characteristic points for three clinical cases ( a lower nasopharyngeal carcinoma, a lung cancer and a cervical cancer). The characteristic points represented the organs at risk or the target. A Mapeheck2 was used to measure dose maps of basic test fields and the treatment fields for the clinical cases. The basic test fields were as follows: 1 ). Symmetric fields in size of 2 cm ×2 cm, 5 cm ×5 cm, 10 cm× 10 cm, 20 cm ×20 cm, 2 cm × 10 cm, 10 cm ×2 cm, 5 cm ×20 cm and 20 cm ×5 cm;2). Asymmetric fields in size of 2 cm ×2 cm (x1 =4 cm, y1 = 10 cm;x2 = -2 cm, y2 = -8cm) and 5 cm ×5 cm (x1 = -2 cm, y1 = -5 cm;x2 =7 cm, y2 = 10 cm) ;3) A 20 cm ×20 cm composite field composed of five 20 cm× 4 cm narrow bar fields side by side. Gamma Index was used to compare calculated and corresponding measured dose distributions. When the criterion was 3% dose difference or 3 mm distance-to-agreement, the pass rate was required to be more than 90%. Results The accuracy of machine output was better than 2% when machine monitor units increased to 4. Among all basic test fields and all the treatment fields of three clinical cases, the maximal absolute dose error was -3.67%, and only the composite test field and two treatment fields of the lower nasopharyngeal carcinoma case had a pass rate slightly less than 90%, which were 83.6%, 88. 3% and 89. 7% ,respectively. For the three clinical cases the treatment delivery times were 15, 14, and 27 minutes, respectively. Conclusions The overall commissioning results are acceptable, and the system can be used in clinic.
8.Establishment of suspension cell line of Atractylodes lancea and effect of endophytic fungal elicitors on its essential oil accumulation
Fang FANG ; Chuanchao DAI ; Bo ZHANG ; Qiaoli LIANG
Chinese Traditional and Herbal Drugs 1994;0(03):-
Objective To establish the suspension cell line of Atractylodes lancea and to study the effect of two endophytic fungal elicitors on its essential oil production.Methods The essential oil was extracted by using ultrasonic wave after suspension cell was treated with endophytic fungal elicitors.Then,the determination of four compounds(atractylone,hinesol,?-eudesmol,and atractylodin) was carried out by gas chromatography.Results By testing in various conditions,the suspension cell line with a rapid growth rate was established.Its highest biomass(6.95 g/L) was obtained on day 21.?-Eudesmol was the only detection in the control suspension cell,and its highest content(17.469 ?g/g) was also reached on day 21.The effect of crude elicitors of two endophytic fungi(belong to Cunninghamella sp.and Gilmaniella sp.respectively,named AL4 and AL12) on the cell growth and the production of essentia1 oil were investigated.Overall AL4 elicitor got better effect.When suspension cell of 14-day-old cultures was exposed to AL4 elicitor(carbohydrate 20 mg/L medium) for 7 d,the biomass increased 3.31% over the control,and the four compounds(atractylone: 14.715 ?g/g,hinesol: 28.395 ?g/g,?-eudesmol: 38.794 ?g/g,and atractylodin: 8.310 ?g/g) were all detected.Among them,the content of ?-eudesmol reached 2.22 times as much as the control.Conclusion The cell growth and the accumulation of essential oil of A.lancea could also be promoted by adding crude elicitors of the endophytic fungi AL4 and AL12.
9.DEVELOPMENT OF A NOVEL SUSPENSION CONCENTRATE OF NICLOSAMIDE AND ITS MOLLUSCICIDAL EFFECT AGAINST ONCOMELANIA SNAILS
Jianrong DAI ; Nianfeng XU ; Yousheng LIANG ; Yao ZHANG ; Yinchan ZHU
Chinese Journal of Schistosomiasis Control 1989;0(01):-
Objective To develop a novel suspension concentrate of niclosamide (SCN) and evaluate its characteristics and molluscicidal effect against Oncomelania snails. Methods Niclosamide was milled by a sand granule mill and mixed with different amounts of wetting agent, dispersant agent, thickener, and water etc., to develop suspension concentrates, and its dispersion, suspensibility and stability were evaluated. According to the results of evaluation the best recipe and quality indexes for producing SCN were selected. The molluscicidal effects against Oncomelania snails were tested under lab condition and in field. Results The novel SCN contained 25% niclosamide (w/w), 1.5%-2.0% wetting agent (RS 3), 4% dispersant (FS 2), 0.10% thickener, a litte of other agent and water. The quality indexes which the SCN reached were as following: the content of niclosamide was more than 25%(w/w); the suspensibal rate was more than 90%; the pH was from 4 to 7; the size of more than 98% granules of niclosamide was smaller than 44?m; the thickener was smaller than 600 mpa.s. The SCN was very stable when it was stored in high or in low temperature. Under lab condition the LC 50 concentrations of SCN by the immersion method for 24, 48 and 72 hours were 0.0474 mg/L, 0.0412 mg/L and 0.0412 mg/L respectively while the LC 50 concentrations of 50% wettable powder of niclosamide (WPN) were 0.0947 mg/L, 0.0583 mg/L and 0.0442 mg/L. In the field death rates of the snails sprayed with 2.0 g/(L?m 2 ) of 25% SCN after 3, 7 and 15 days were 95.77%, 99.07%, 97.09% while the death rates of the snails sprayed with 2.0 g/(L?m 2 )of 50% WPN were 97.37%, 95.17% and 97.41%. Conclusion SCN had stable quality and high molluscicidal effect against Oncomelania snails, and it was suitable to be used in the field. The molluscicidal effect using 2.0 g/(L? m 2 ) of 25% SCN was similar with that using 2.0 g/(L?m 2) of 50% WPN.
10.Comparison of the effects between the Xuebijing and the Danshen injection on ischemic-reperfusion injury of rabbit limb
Liang ZHANG ; Wei DAI ; Zhiming GAO ; Jihong ZHOU ; Dawei LIU
Chongqing Medicine 2013;(31):3724-3727,3731
Objective To study and compare the effects and mechanisms between the Xuebijing injection and Danshen injection on ischemic-reperfusion injury of rabbit limb .Methods 30 New Zealand rabbits were randomly divided into control group ,Xuebi-jing group and Danshen group ,with 10 in each group .The Crinnion model of ischemic-reperfusion injury of rabbit limb was used . Each group was treated correspondingly after the blood flow was restored .Xuebijing group and Danshen group were treated with 4 mL/kg Xuebijing injection 2 mL/kg Danshen injection in saline with 10 mL total volume .Control group was treated with 10 mL sa-line .Before releasing clip and 1 h ,2 h and 4 h after reperfusion ,the blood samples were collected for detecting clotting function (APTT ,FIB ,PT-INR ,PT) ,biochemistry items (ALB ,LDH ,CK) ,MDA level and SOD level .Results Compared with control group ,the APTT of Xuebijing group in 1 h and 2 h and Danshen group in 4 h after reperfusion improved significantly (P<0 .05) . The PT of Xuebijing group after reperfusion extended significantly compared with the PT before reperfusion (P<0 .05) .The FIB level of Xuebijing group and Danshen group in 4 h after reperfusion was much higher than before (P<0 .05) .The LDH and CK level of Xuebijing group after reperfusion was much lower than that of control group (P< 0 .05) .The MDA level of Xuebijing group in 2 h and Danshen group in 1 h ,2 h after reperfusion was much lower than that of control group (P<0 .05) .The SOD activ-ity of Xuebijing group in 1-4 h and Danshen group in 2 h after reperfusion was much higher than that of control group (P<0 .05) .Conclusion Xuebijing injection and Danshen injection have the relieving effect on the limb ischemic-reperfusion injury by ad-justing clotting function and decreasing free oxygen radicals .In terms of relieving the injury of muscle tissue ,the effect of Xuebijing injection might be better than Danshen .