Objective:To investigate the association of human leucocyte antigen-DRB1 alleles with chronic hepatitis B and hepatic cirrhosis in Han population of Jilin area.Methods:HLA-DRB1 alleles in 61 patients with chronic hepatitis B,44 patients with hepatic cirrhosis,32 spontaneous rehabilitees after HBV infectin,and 50 healthy controls were analyzed by using polymerase chain reaction/sequence specific primer technique.Results:The frequency of HLA-DRB1*1201-3 allele in chronic hepatitis B group was higher than that in healthy control group(17.21% vs.8.00%,P=0.0427,RR=2.391).The frequency of HLA-DRB1*0701 allele in chronic hepatitis B group and hepatic cirrhosis group was markedly higher than that in healthy controls group(11.48 % vs.2.00%,P=0.006 6,RR=6.35;12.50% vs.2.00%,P=0.004 6,RR=7.00)and in spontaneous rehabilitee group (11.48% vs.1.56%,P=0.0183,RR=8.17;12.50% vs.1.56%,P=0.0136,RR=9.00).No significant differences frequencies of the other HLA-DRB1 alleles were observed among the four groups.Conclusion:Alleles of HLA-DRB1*1201-3 and HLA-DRB1*0701 are closely associated with chronic hepatitis B and maybe susceptible genes or linkage genes of chronic hepatitis B.HLA-DRB1*0701 is also closely associated with hepatic cirrhosis and maybe a susceptible gene or linkage gene-posthepatitis B-cirrhosis in Han population of Jilin area.

Objective To discuss the MRI features and pathogenic mechanisms of lung cancer intramedullary spinal cord metastasis (ISCM). Methods Four cases with clinically and 3 cases pathologically proved lung cancer ISCM were analyzed retrospectively. Turbo spin-echo sequence T 1 and T 2 weighted images were acquired in all patients. T 1 weighted images were obtained after intravenous administration of Gd-DTPA in all patients. Results A total of 7 ISCM were displayed by MR studies. The tumor occurred in thoracic cord (3/7) and in medullary cone (4/7). The tumor involved the central aspect of the cord. The lung cancer ISCM showed hypointensity (n=1) or isointensity (n=6) on T 1WI and hyperintensity on T 2WI. The extensive cord enlargement with cyst formation or syringomyelia was common. On contrast study, all tumors showed marked homogenous enhancement with clear borders. Conclusion The lung cancer ISCM usually presented as solitary lesions with marked contrast enhancement. The extensive cord enlargement was common in all patients. Because of the limitation in the evaluation of lung cancer ISCM on MRI, definite diagnosis of lung cancer ISCM depended on combination of clinical and MRI data.

Virophages have crucial roles in ecosystems and are the transport vectors of genetic materials. To shed light on regulation and control mechanisms in virophage--host systems as well as evolution between virophages and their hosts, the promoter motifs of virophages were predicted on the upstream regions of start codons using an analytical tool for prediction of promoter motifs: Multiple EM for Motif Elicitation. Seventeen potential promoter motifs were identified based on the E-value, location, number and length of promoters in genomes. Sputnik and zamilon motif 2 with AT-rich regions were distributed widely on genomes, suggesting that these motifs may be associated with regulation of the expression of various genes. Motifs containing the TCTA box were predicted to be late promoter motif in mavirus; motifs containing the ATCT box were the potential late promoter motif in the Ace Lake mavirus . AT-rich regions were identified on motif 2 in the Organic Lake virophage, motif 3 in Yellowstone Lake virophage (YSLV)1 and 2, motif 1 in YSLV3, and motif 1 and 2 in YSLV4, respectively. AT-rich regions were distributed widely on the genomes of virophages. All of these motifs may be promoter motifs of virophages. Our results provide insights into further exploration of temporal expression of genes in virophages as well as associations between virophages and giant viruses.
Base Sequence ; Evolution, Molecular ; Genome, Viral ; genetics ; Genomics ; Nucleotide Motifs ; genetics ; Promoter Regions, Genetic ; genetics ; Satellite Viruses ; genetics

Objective To evaluate the effects of four types of variance reduction techniques ( ring counter grid, high electron cutoff energy, termination of electron tracking in some structures, and emission direction?biased sampling of source) on the efficiency and accuracy of Monte Carlo simulation for the single source channel of the Leksell Gamma Knife. Methods The single source channel of the Leksell Gamma Knife was modeled using Monte Carlo software MCNP . Four types of variance reduction techniques were used to simulate the dose distribution in the water?like phantom. The computation efficiency and simulation result were compared between the four techniques. Results All techniques substantially improved the computation efficiency and had little effect on the accuracy of the simulation ( relative error less than 2. 5%) . However, if the electron cutoff energy was above 50 keV, the simulation became quite inaccurate due to neglect of the scattering of high?energy electrons and their dosimetric contribution to the penumbra. When the scattering of high?energy electrons and their dosimetric contribution to the penumbra were ignored, the dose to the Profile platform was overestimated and the dose to the penumbra was underestimated. Conclusions Rational use of variance reduction techniques can substantially improve the efficiency of Monte Carlo simulation for the single source channel of the Leksell Gamma Knife. However, the impact of variance reduction techniques on the accuracy of the simulation should be carefully evaluated.

Objective To develop whole breast irradiation with volumetric-modulated arc therapy (VMAT)-based hybrid intensity-modulated radiotherapy (IMRT) after breast conserving surgery for breast cancer,and to evaluate its value in clinical application.Methods Ten patients with breast cancer undergoing breast conserving surgery were enrolled.Two radiotherapy plans were designed based on hybrid fixed-beam IMRT/IMRT technique and hybrid VMAT/IMRT technique,respectively.One group received whole breast irradiation with a prescribed dose of 50 Gy in 25 fractions.The other group received whole breast irradiation with a prescribed dose of 50 Gy in 25 fractions,as well as simultaneous integrated boost to the tumor bed with 60 Gy in 25 fractions.The dosimetric parameters and delivery efficiency were compared between the two plans using paired t test.Results For patients treated with whole breast irradiation alone,there were no significant differences in conformity index and homogeneity index of target volume between the two plans (P=0.866,0.056);however,compared with the hybrid fixed-beam IMRT/IMRT technique,the hybrid VMAT/IMRT technique significantly increased the doses to organs at risk (OARs) and the number of monitor units (MUs) in the intensity-modulated field (P=0.000-0.050,P=0.002).For patients treated with whole breast irradiation with a simultaneous integrated boost to the tumor bed;however,the hybrid VMAT/IMRT technique significantly reduced the doses to the lung and spinal cord,number of MUs in intensity-modulated field,and delivery time compared with the hybrid fixed-beam IMRT/IMRT technique (P=0.004,0.001,0.000,0.000).Conclusions For patients treated with whole breast irradiation with a simultaneous integrated boost to the tumor bed,the hybrid VMAT/IMRT technique is highly promising for clinical application due to better OAR sparing and higher delivery efficiency.

Objective To investigate the effects of lentiviral-mediated RNA interference (RNAi) targeting tumor necrosis factor-α(TNF)-αgene on the expression of TNF-α, interleukin (IL)-1β, IL-6 of murine macrophages RAW264.7, and the efficiency of RNAi experimental gene therapy for the murine collagen-induced arthritis (CIA). Methods The RAW264.7 macrophages were infected by lentivirus-RNAi particles, then stimulated by Lipopolysaccharides (LPS). The TNF-α, IL-1β, IL-6 expression of RAW264.7 macrophages were measured with real-time polymerase chain reaction (PCR) and enzyme linked immunosorbent assay (ELISA). CIA models were esta-blished in DBA/1 mice using bovine type Ⅱ collagen. The treatment effect of lentivirus-RNAi on CIA were observed through arthritis scores, serum TNF-α measurement and hind paw paraffin section hematoxylin/eosin staining after lentivirus-RNAi particles tail vein injection. Results The TNF-αmRNA relative expression level of lentiviral RNAi group was 0.291 ±0.021, significantly lower than that of negative control group 0.925±0.013 (t=25.4, P<0.01). The inhibition rate in mRNA levels was 68.5%. The serum TNF-α level of lentiviral RNAi group was [(249 ±11) ng/ml], significantly lower than that of negative control [(382±6) ng/ml] (t=10.31, P<0.05). The inhibition rate of protein levels was 34.7%. It had no effect on the IL-1β and IL-6 mRNA expression. On the 8th day after systemic administration, the arthritis score of lentivirus-RNAi group was 2.50±0.19, which was significantly lower than that of blank controls (3.63 ±0.18) and negative controls (3.75 ±0.16) (F=42.8, P<0.01). From now on, arthritis score of lentivirus-RNAi group and positive control decreased slowly to at least 2 weeks after treatment induction. The serum TNF-α levels of lentivirus-RNAi group and positive controls were [(35±6) pg/ml] and [(32±7) pg/ml] significantly lower than that of negative controls [(47±3) pg/ml] (t=3.03, 4.11, P<0.01) respectively. Morphological examination showed that the lentivirus-RNAi decreased CIA pathological manifestations. Conclusion Lentiviral-mediated RNAi targeting murine TNF-α gene can effectively inhibit TNF-α expression both in vitro and in vivo, which also effectively improve the CIA arthritis score. Lentiviral-mediated RNAi targeting TNF-αgene provides a potential strategy for rheumatoid arthritis (RA) treatment.

Objective To evaluate the plan quality of volumetric modulated arc therapy (VMAT) in single brain metastasis compared with the stereotactic arc therapy (S_ARC).Methods 31 patients were replanned using VMAT and S_ARC technique.Prescription dose is 40 Gy delivered in 4 fractions covering at least 95％ of the target volume while keeping minimum doses to the volume of normal brain tissue.The plans were assessed and compared using the conformity indexes (CI),gradient indexes (GI),the mean dose of normal brain tissue,the volumes of normal brain tissue receiving 4 Gy doses,the number of monitor unit and treatment times.A paired t test or non-parametric Wilcoxon signed rank test was performed to analyze the difference between these two plans.Results VMAT plans increased dose conformity,but not dose gradient,compared with S_ARC plans.The median dose conformity index values were 0.815,0.818,and 0.779 (P =0.000,0.000),and the median dose gradient score index values were 5.865,5.706,and 3.133(P =0.000,0.000,0.000),in single arc,double arc VMAT plans and S_ARC plans,respectively.The mean dose of normal brain tissue was higher in VMAT plans.And the volume of the normal brain tissue receiving doses of 4 Gy in VMAT plans was significantly larger than the volume in S_ARC plans.The VMAT plans got higher MU number (P =0.000,0.000).And the mean treatment times were (2.7 ± 0.1) min,(2.8 ± 0.1) min,and (7.6 ± 0.2) min in single arc,double arc VMAT plans and S_ ARC plans,respectively (P =0.000,0.000).Conclusions The dosimetry of VMAT plan can meet the requirements of clinical,and is recommended in the treatment of big volume single brain metastasis or single brain metastasis in cerebellum.

Objects To study the protective effects of cimetidine against oxidative stress in rats induced by cumulative low-dose irradiation.Methods Sixty SD rats were randomly divided into 6 groups (10 each):normal control group,model control group,lentinan group [89mg/(kg.d)] and 3 dose groups of cimetidine.After oral administration,all the rats were exposed to γ-ray irradiation 8 hours/day for 12 days,and sacrificed on the 13th day.The activities of superoxide dismutase (SOD),glutathione peroxidase (GPx),catalase (CAT) and the content of malondialdehyde (MDA) in serum,liver,thymus and spleen were determined.By using the superoxide anion radical system,hydroxyl radical system,H2O2 radical system,oxidation system of linoleic acid induced by alkane radical system and diphenyl picryl hydrazinyl radical (DPPH) radical system,the antioxidation activities of cimetidine were detected.Results The activities of SOD in liver and thymus decreased significantly,the GPx activity in serum,liver and spleen decreased significantly and MDA level in serum,liver and spleen increased significantly after 0.3Gy cumulative ionizing radiation.Cimetidine enhanced the activities of antioxidant enzymes in serum and organs,and reduced the MDA level.In a certain concentration range,cimetidine had different scavenging effects onto these radical systems,and showed good performance in hydroxyl radical.Conclusion Cimetidine can effectively ameliorate the oxidative stress from low-dose cumulative irradiation by scavenging free radicals,increase the activity of antioxidant enzymes and reduce the content of lipid peroxidation products,thus presents a potential radio protective effect.

Objective Explore the reversibility and potential molecular mechanisms of pulmonary hypertension in pa-tients with complete transposition of the great arteries (cTGA) combined with ventricular septal defect (VSD) in comparison with those with simple VSD. Methods Twenty-four patients with pulmonary hypertension (mean pulmonary arterial pressure was greater than 30 mmHg) were enrolled in our study, in which 10 patients suffered from cTGA with VSD, and the rest 14 pa-tients suffered from simple VSD. Lung specimens were taken from the right middle lobe of lung before cardiopulmonary bypass. The extent of pulmonary hypertension was then graded according to the Heath-Edwards classification. ELISA was used to exam-ine the expression of eNOS, iNOS, ET-1, ET-AR, ET-BR, MMP-2, MMP-9 and TIMP in all the specimens. Results No statistically significant differences in age, height, weight, the size of VSD, and the pulmonary artery pressure before operation were found between the groups. The level of hemoglobin, aortic and pulmonary arterial oxygen saturation, and the reduction value of pulmonary arterial pressure after surgery were significantly higher in the cTGA patients than that in the simple VSD pa-tients (P < 0.05). All patients had grade 0 - Ⅱ Heath-Edwards changes in their lung biopsy samples. The expression of eNOS and MMP-2 was significantly lower in the TGA group than that in the simple VSD group [eNOS: (280.13 ± 101.92) ng/mg vs. (488.41±249.6) ng/mg, P<0.05; MMP-2:(31.68±15.36)ng/mg vs. (69.28±49.12)ng/mg, P<0.05]. There were no statistically significant differences between the two groups regarding the expression of iNOS, ET-1, ET-AR, ET-BR,MMP-9 or TIMP. Conclusion The imbalance of the NOS/ET system and the MMP/TIMP system involves in the development of pulmonary hypertension in patients with TGA combined with VCD. In patients with cTGA, the high oxygenation state in pul-monary circulation may decrease the expression of MMP2 and eNOS, and may affect the progress of pulmonary hypertension to a certain extent.

Objective To analyze the strains of patients with hypertrophic cardiomyopathy (HCM) by vector velocity imaging(VVI),and to identify abnormal early systolic function.Methods Forty patients with HCM (HCM group) and 25 healthy subjects (control group) were enrolled.Standard two-dimensional echocardiography was performed.Left ventricular ejection fraction (LVEF),diameters and wall thickness were measured.Peak systolic strains in all directions and their time to peak were analyzed off-line.Results ①All but the endocardial circumferential strain were apparently smaller in HCM group than those in the control group(P ＜0.000 1).The difference was greater in long axis than that in short axis.②The HCM group maintained the characteristics of strain gradient as the control group,including the endocardiumepicardium gradient with endocardial strains was significantly greater than epicardial ones and the base-apex gradient,among which epicardial longitudinal strain decreased from the base to the apex and endocardial circumferential strain increased toward the apex.③The HCM group suffered significant dyssynchrony in terms of strain and rotation,with greater changes in longitudinal than in short axis,in epicardium than in endocardium.Conclusions VVI offers an overall assessment of regional and global left ventricular systolic function,including longitudinal and circumferential strain.Moreover,it can be used to evaluate subclinical systolic dysfunction and dyssynchrony in patients with HCM.