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.Research progress of human resource management for the nurses at age of marriage and childbearing and enlightenment
Fumin DAI ; Liang WANG ; Hongmei ZHANG ; Huinan ZHAO ; Jinjin GUO
Chinese Journal of Practical Nursing 2015;31(23):1789-1792
With the public hospitals expanding,the nurses at age of marriage or bearing are enrolled and account for large part of all health care workers in China.A significant percentage of nurses in the period of pregnancy or lactation,especially abortion and sterility,deteriorate the shortage of nursing human resources and the nurses' health.It is essential to cope with the matter in order to maintain the nurses and contribute to the professional development.In this paper,we review the human resource management of the nurses during the periods at home and abroad from the human resources,occupational protection and management approaches,which is contributed to supplement the human resource.
6.Cloning and synthesis of a new A-superfamily conotoxin Bt14.10
Fei WANG ; Longxiao ZHANG ; Liang LI ; Zhuguo LIU ; Qiuyun DAI
Military Medical Sciences 2014;(8):598-601
Objective To clone a new conotoxin Bt14.10 from Conus betulinus derived from the South China Sea, synthesize the peptide , and to determine linkage of its disulfide bridges .Methods The genomic DNA was extracted from C.betulinus venom duct while the Bt14.10 sequence was cloned using primers designed based on the untranslated region and intron.The peptide was then synthesized using solid-phase method and folded into the target product whose disulfide bridge connection was further determined by two-step oxidative folding .Results A novel conotoxin designated as Bt 14.10 (CAHSVPGMHPCKCNNTC-NH2) was obtained,the disulfide connectivity of which was C1-C3,C2-C4.Conclusion Bt14.10 is a new A-superfamily conotoxin and has a distinct loop spacing pattern between cysteines in A-superfamily conotoxins.
7.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.
8.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.
9.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 .
10.Cloning, synthesis and target identification of a novel α-conotoxin Lt1.1
Huying NING ; Liang LI ; Longxiao ZHANG ; Zhuguo LIU ; Qiuyun DAI
Military Medical Sciences 2017;41(5):334-337
Objective To discover novel conopeptides which are the antagonists of neuronal nicotinic acetylcholine receptors (nAChRs) in order to contribute to the development of novel analgesic drugs and neuropharmacological probes.Methods Based on the conserved untranslated region and intron of A-superfamily conotoxins,a novel α-conotoxin Lt1.1 was cloned from Conus litteratus.The peptide-resin was synthesized using the solid-phased method and was cleaved.The resulting linear peptide was oxidized by air to give the product containing disulfide bridges.The folding product was finally purified by HPLC.The disulfide bond connectivity was determined using the two-step oxidative folding methods.The cRNA of rat nAChRs was expressed on the membrane of Xenopus oocyte.Membrane currents were recorded using the two electrode voltage-clamp technique.Results A novel α-conotoxin designated as Lt1.1(GCCSHPACNVNNPDIC-NH2) was cloned and its disulfide connectivity was C1-C3,C2-C4.Lt1.1 selectively inhibited the α3β2 and α3β4 nAChRs with an IC50 of 166.76 and 190.00 nmol/L,respectively.Conclusion Lt1.1 is a novel 4/7 α-conotoxin that selectively targets α3β2 and α3β4 nAChRs.