1.Optimization study on clinical dose calculation in semi-field irradiation
Jingbin CHEN ; Tengjiong LI ; Zhixiao ZHOU
China Medical Equipment 2014;(5):27-29
Objective: A correction factor was proposed to improve the accuracy of dose calculation in conventional radiotherapy when filed matching technique was used. Methods:Use the linear accelerator with independent collimator to implement semi-field irradiation under different equivalent-length field. Measure the dose and compare it with the calculation dose. Obtain a correction factor which change follow the equivalent-length through data fitting. Results:There is relationship to indicate the correction factor increase if the field area enlarge;the calculation dose will be close to the measure dose, and the accuracy will improve by correcting;Conclusion:The clinical dose of semi-field irradiation can be calculated by an equivalent square field technique , and then multiplied by the correction factor. it is a simple method to improve the accuracy of dose calculation in conventional radiotherapy by using semi-filed correction factor when filed matching technique was used.
2.A hydroponic cultivation system for rapid high-yield transient protein expression in Nicotiana plants under laboratory conditions.
Qianzhen MO ; Rongjia MAI ; Zhixiao YANG ; Minfang CHEN ; Tiezhao YANG ; Huafang LAI ; Peiliang YANG ; Qiang CHEN ; Xiaohong ZHOU
Journal of Southern Medical University 2012;32(6):772-777
OBJECTIVETo develop a hydroponic Nicotiana cultivation system for rapid and high-yield transient expression of recombinant proteins under laboratory conditions.
METHODSTo establish the hydroponic cultivation system, several parameters were examined to define the optimal conditions for the expression of recombinant proteins in plants. We used the green fluorescent protein (GFP) and the geminiviral plant transient expression vector as the model protein/expression vector. We examined the impact of Nicotiana species, the density and time of Agrobacterium infiltration, and the post-infiltration growth period on the accumulation of GFP. The expression levels of GFP in Nicotiana leaves were then examined by Western blotting and ELISA.
RESULTSOur data indicated that a hydroponic Nicotiana cultivation system with a light intensity of 9000 LX/layer, a light cycle of 16 h day/8 h night, a temperature regime of 28 degrees celsius; day/21 degrees celsius; night, and a relative humidity of 80% could support the optimal plant growth and protein expression. After agroinfiltration with pBYGFPDsRed.R/LBA4404, high levels of GFP expression were observed in both N. benthamiana and N. tobaccum (cv. Yuyan No.5) plants cultured with this hydroponic cultivation system. An optimal GFP expression was achieved in both Nicotiana species leaves 4 days after infiltration by Agrobacterium with an OD(600) of 0.8. At a given time point, the average biomass of N. tobaccum (cv. Yuyan No.5) was significantly higher than that of N. benthamiana. The leaves from 6-week-old N. benthamiana plants and 5-week-old N. tobaccum (cv. Yuyan No.5) plants could be the optimal material for agroinfiltration.
CONCLUSIONWe have established a hydroponic cultivation system that allows robust growth of N. benthamiana and N. tobaccum (cv. Yuyan No.5) plants and the optimal GFP expression in the artificial climate box.
Gene Expression Regulation, Plant ; Genetic Vectors ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Hydroponics ; methods ; Plants, Genetically Modified ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Tobacco ; genetics ; growth & development
3.Diagnostic value of hepatobiliary imaging combined with serum γ-GT/TBA ratio in children with congenital extrahepatic biliary atresia
Hui ZHOU ; Junhong LI ; Aifeng LI ; Hailian WEI ; Zhixiao WEI ; Xiaonan ZHANG ; Shengmei PENG
Chinese Journal of Nuclear Medicine and Molecular Imaging 2018;38(11):736-740
Objective To study the diagnostic value of hepatobiliary imaging at 6 h post-injection of 99 Tcm-diethyl iminodiacetic acid ( EHIDA) ( HI-6) combined with serum gamma-glutamyltransferase (γ-GT)/total bile acid ( TBA) ratio ( combined diagnosis) in children with congenital extrahepatic biliary atre-sia (CEBA). Methods Clinical data of 194 pediatric patients (118 males, 76 females, mean 70.9 d) with jaundice from May 2013 to March 2017 were retrospectively analyzed. All patients underwent surgery. According to the operation and pathologic diagnosis, patients were divided into CEBA group ( 113 cases) , infant hepatitis syndrome ( IHS) group ( 81 cases) . Serumγ-GT, TBA and the ratio ofγ-GT/TBA of the 2 groups were compared. Receiver operating characteristic ( ROC) curves were drawn to determine threshold values of the 3 parameters for diagnosis of CEBA. Patients also underwent 99 Tcm-EHIDA hepatobiliary dy-namic imaging. The diagnostic efficacies of HI-6, γ-GT, γ-GT/TBA ratio, and combined diagnosis were compared. Two-sample t test and χ2 test were used to analyze the data. Results There were significant differences in γ-GT/TBA ratio,γ-GT and TBA content between the 2 groups (t values:8.217, 9.298 and 2.426, all P<0.05). The serumγ-GT andγ-GT/TBA ratio had high diagnostic accuracies (area under ROC curve ( AUC):0.884 and 0.863) . The sensitivity, specificity, accuracy and positive predictive value of HI-6 in the diagnosis of CEBA were 91.15%(103/113), 39.51%(32/81), 69.59%(135/194) and 67.76%(103/152);the parameters of γ-GT were 69.91%(79/113), 93.83%(76/81), 79.90%(155/194) and 94.05%(79/84);and those ofγ-GT/TBA ratio were 71.68%(81/113), 92.59%(75/81), 80.41%(156/194) and 93.10%(81/87). The sensitivity of HI-6 was significantly higher than that of γ-GT and GGT/TBA ratio (χ2 values:16.256 and 14.154, both P<0.05) , but the specificity, accuracy and positive predic-tive value were significantly lower than those ofγ-GT/TBA ratio (χ2 values:50.899, 6.062 and 20.054, all P<0.05). The specificity, accuracy and positive predictive value of the combined diagnosis were 95.06%(77/81), 92.78%(180/194) and 96.26%(103/107) respectively, which were significantly higher than those of HI-6 (χ2 values:56.786, 34.168 and 31.335, all P<0.05) . Conclusions HI-6 combined withγ-GT/TBA ratio can significantly improve the diagnostic specificity and accuracy for CEBA. This method is more time-saving, simple and reliable, and has important clinical value.
4.Expression and significance of miR-21 in primary gout patients
Gang CHEN ; Menglan LI ; Chunmei PENG ; Zhixiao YOU ; Wenguang XIE ; Jingguo ZHOU
Chinese Journal of Rheumatology 2019;23(3):165-169
Objective To explore the expression and significance of miR-21 in patients with primary gout. Methods The patients were divided into 4 groups: 35 acute gout patients (AG), 50 intermittent gout patients (IG), 25 chronic gout patients (CG) and 39 healthy patients. Their peripheral blood were collected and laboratory indexes were recorded. The expression of miR-21 and Nod-like receptor pyrin domain-containing protein 3 (NLRP3) mRNA in the peripheral blood mononuclear cells (PBMCs) was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The blood and clinical data of another 5 healthy volunteers were collected, their peripheral blood was stimulated with 100 μg/ml monosodium urate (MSU) for 1 hour, pho-sphate buffer (PBS) was used as controls, then the expression of microRNA (miR)-21, NLRP3, interleukin (IL)-1β mRNA was detected by RT-qPCR. Rank sum test and spearman correlation analysis were used for data analysis. Results In primary gout patients, the expression of miR-21 in AG [12 ×10-4 (8.0 ×10-4)], IG [9.4 ×10-4 (6.9 ×10-4)], CG [7.3 ×10-4 (5.6 ×10-4)] was significantly higher than that in healthy control group [1.0×10-4(2.0×10-4)] (Z=9.83, P=0.02], while the expression of NLRP3 in AG[0.0444(0.0233)], IG[0.0581(0.0326)], CG[0.0314(0.0198)] was significantly lower than that in healthy control group [0.0886(0.0359)] (Z=13.82, P<0.01). In the primary gout of IG group, the expression of miR-21 was positively correlated with NLRP3 mRNA (r=0.449, P=0.016). After stimulated by 100 μg/ml MSU, the expression of miR-21 of the stimulated group [8.78×10-4(14×10-4)] was higher than that in the control group [6.25×10-4(6×10-4)](Z=-2.203, P<0.05), and the expression of IL-1βin stimulated group [3.06(2.00)] was higher than that in the control group [2.64 (1.22] (Z=-2.203, P<0.05). The level of miR-21 in patients with primary gout was positively correlated with the level of uric acid (UA), glutamic oxaloacetic transaminase (AST) and glutamic pyruvic transaminase (ALT) (r=0.473, 0.639, 0.487, P<0.05). Conclusion The increase of miR-21 in patients with primary gout may be involved in the inflammatory reaction of gout.
5.Human parvovirus B19 infection in blood donors: a meta-analysis
Zhixiao WANG ; Beibei ZHOU ; Na ZHANG ; Haiyan HUANG
Chinese Journal of Blood Transfusion 2022;35(2):171-175
【Objective】 To analyze the current situation of human parvovirus B19 infection in blood donors in different regions of China, so as to provide basis for formulating reasonable screening programs of B19 virus for blood donors in various cities and regions. 【Methods】 The literatures related to human parvovirus B19 infection in whole blood and plasma donors published from 1998 to 2021 were searched in the database, and meta-analysis of literatures that satisfied the inclusion criteria was conducted by R4.1.0 software. 【Results】 A total of 35 literatures were obtained, 20 literatures involving 56 846 blood donor samples and 8 literatures involving 1 608 pooled raw plasma samples were subjected to Meta analysis of the positive rates of B19 DNA; 17 literatures involving 12 308 blood sample were subjected to the Meta analysis of the positive rate of B19 IgG antibody.The positive rates of B19 DNA in blood donors(I2=96%, τ2=0.026 0, P<0.01)and pooled raw plasma (I2=98%, τ2=0.124 5, P<0.01), as well as the positive rate of B19 IgG antibod (I2=98%, τ 2 =0.021 0, P < 0.01) presented significant heterogeneity between regions. The combined positive rate of B19 DNA was estimated to be 2.0% (95%-CI: 0.007~0.039), that of pooled raw plasma for production was 66.6% (95%-CI: 0.476~0.832), and that of B19 IgG antibody was 30.2% (95%-CI: 0.246~0.357). 【Conclusion】 Low HPV B19 infection rate and high positive rate of IgG antibody were found in blood donors. Therefore, the risk of B19 virus infection due to blood transfusion is low, but B19 infections in blood donors varied significantly between regions. Domestic cities and regions should reasonably evaluate their own B19 virus infection status to formulate appropriate B19 virus screening programs for blood donors, so as to reduce blood transfusion transmitted risk of B19 virus. In addition, the infection rate of B19 virus in pooled plasma for production is somewhat high. Recipients should be screened for B19 virus antibodies, and appropriate blood transfusion schemes should be formulated for blood recipients lacking neutralizing B19 IgG antibodies to reduce the exposure of B19 virus.