Objective To analyze the image noise and artifact of low-dose chest CT scanning and the distribution pattern. Methods A chest phantom equivalent to human tissue was scanned by 64 slices spiral scanner at standard dose (250 mAs) and low-dose (50, 30,and 21 mAs) respectively, HU in sites of the phantom and SD of which was recorded. 200 patients with pulmonary nodules were scanned at 30 or 21 mAs for minimal length. The relationship between severity of noise and artifact in chest low-dose CT scanning and gender or body mass index (BMI) of the patients, as well as the distribution of noise and artifact was evaluated. Results There was no statistical difference between the HU in sites of the phantom: lung (-777.3-- -758.2 HU, F=0.992, P<0.01), chest wall (107.9--111.3 HU, F=2.044, P>0.05), vertebra (835.6--875.3 HU, F=1.453, P>0.05), while the SD of which was of statistical signification: lung (9.5--29.0 HU, F=108.7, P<0.01), chest wall (10.1--32.4 HU, F=84.3, P<0.01), vertebra (19.2--57.1 HU, F=30.6, P<0.01),tbe SD increased with the decrease of the tube current. There was no statistical difference between male (in which 74 cases no or mild, 17 cases severe)and female (81 cases no or mild, and 28 cases severe)in image noise and artifact in low-dose images (X~2=2.294, P>0.05), and significant difference between groups of different BMI(in BMI<18.5 group, 29 cases no or mild,2 cases severe, in group of 18.5≤BMI<24.0, 120 cases no or mild, 13 cases severe, and in group of BMI≥24.0, 6 cases no or mild, 30 cases severe, X~2=128.274, P<0.01). The noise andartifact was greater in the upper (80 cases no or mild, 38 cases severe, X~2=18.918, P<0.01) and dorsal field (89 cases no or mild, 33 cases severe, X~2=6.760, P<0.05). Conclusions The image noise and artifact was significant in low-dose CT, especially in the dorsal and upper field of the lung, which might be attributed to the distribution of skeleton in the chest. It was recommended that scanning protocol (mAs value) be individualized adjusted in according to the patients BMI.

Objective To evaluate the sensitivity and optimized scanning parameter of 64-slice spiral CT in detection of pulmonary nodules with different size and density. Methods Three groups of prosthesis nodules with diameter of 2.5～13 mm and different density (soft-tissue, low density, and ground glass opacity,GGO)were taken into the chest phantom equivalent to human tissue,then scanned with Philips Brilliance 64 scanner in standard dose(tube voltage:120 kV, tube current: 250 mAs)and low-dose(tube voltage:120 kV, tube current: 50, 30,and 21mAs) respectively. The radiation dose(CTDIw and DLP) of the scans, Hounsfield unit(HU) and standard deviation(SD) of CT values in different regions of the phantom, and visibility of the nodules was assessed and recorded.Results The radiation dose of 64-slices spiral CT scanning in low-dose(tube current 21～51 mAs) decreased to 8%～20% of which scanning in standard-dose(250 mAs). There was no statistical difference between the CT values in different regions of the phantom (P>0.05), while the SD of CT values was of statistical significantce (P<0.001) and SD increased with the increment of the density under different scanning parameters. None of the nodules besides of GGO nodules with 2.5 mm and 4 mm in size scanned at 21 mAs was invisible. Conclusion GGO nodules of 2.5 mm in diameter can be detected with 64-slice spiral CT using 30 mAs at experimental study, which might be the optimized dose for detecting pulmonary nodules.

AIM: To establish a method of determining genpioside,baicalin and berberine in Gonglao Quhuo Tablets(Caulis Mahoniae,Cortex Phellodendri Chinensis,Radix Scutellariae,etc). METHODS: The mobile phase composed of A acetonitrile,B acetonitrile and 0.5% triethylamine(Ph3.1)(10∶90).The flow rate was 1.0 mL/min with the wavelength at 254 nm. RESULTS:The calibration curves were linear in the ranges of 3.22-206 ?g/mL(r=0.999 9) for genpioside,2.95-186 ?g/mL(r=0.999 9) for baicalin and 1.64-104 ?g/mL(r=0.999 9) for berberine hydrochloride,respectively.The average recoveries were not less than 98.4%. CONCLUSION: This HPLC method is convenient,rapid,accurate and could be used for quality control of production of Gonglao Quhuo Tablets.

Objective To analyze the differences in symptoms spectrum,lifestyle,diet and psychological features among different age groups with reflux esophagitis.Methods From June 2011 to October 2013,332 outpatients with reflux esophagitis (RE) were collected and divided into youth group (18 to 40 years),middle-aged group (41 to 64 years) and aged group (≥65 years).Symptoms and risk factors of patients were investigated.The severity of the symptoms was evaluated with reflux diagnostic questionnaire (RDQ).The anxiety and depression of patients were assessed with self-rating anxiety scale (SAS) and self-rating depression scale (SDS).The distribution of symptoms spectrum,the severity of symptoms,lifestyle,diet and psychological features of three groups were compared.Mann-Whitney U tests or Chi-square test were used for comparison between two groups.Pearson test was performed for correlation analysis.Results There were 96 cases,192 cases and 44 cases in youth,middle-aged and aged group,respectively.Compared with youth group and middle-aged group,the incidence of chronic cough and asthma (extra-esophageal symptoms) was higher in aged group (1.0％ (1/96),13.5％ (26/192),20.5 ％ (9/44);and 3.1％ (3/96),9.4 ％ (18/192),15.9 ％ (7/44)),and the differences were statistically significant (x2 =15.10 and 6.91,both P＜0.05).The scores of extra-esophageal symptoms in youth group,middle-aged group and aged group were 7.0(2.0,14.0),9.5(4.2,17.0) and 12.0(7.0,19.7),respectively,and the difference was statistically significant (F=3.93,P =0.02).Comparison with aged group,the incidences of youth group and middle-aged group were higher in irregular meals (4.5 ％ (2/44),28.1％(27/96),14.6％ (28/192)),overeating (29.5％(13/44),50.0％(48/96),34.9％(67/192)),dinner time after 19 o'clock (2.2％(1/44),27.1％(26/96),20.3％(39/192)),lying down in 30-minute post-meal (40.9％(18/44),63.5％(61/96),49.5％(95/192)),high fat diet (52.3％(23/44),84.4％ (81/96),69.3％(133/192)),spicy food (13.6％(6/44),43.8％(42/96),30.7％(59/192)),and the differences were statistically significant (x2 =13.93,7.90,11.71,10.36,16.22 and 12.99,all P＜ 0.05).Compared with the youth group and middle-aged group,the incidence of aged group was higher in exercise times ＜two times/week (15.6 ％ (15/96),40.1％ (77/192),50.0％ (22/44)),preference of tea (36.5％(35/96),36.5％(70/192),59.1％ (26/44)) and poor sleep quality (13.5％ (13/96),19.3％ (37/192),31.8％(14/44)),and the differences were statistically significant (x2 =22.52,8.18 and 6.47,all P＜ 0.05).The median SAS scores of youth group,middle-aged group and aged group were 30.0 (27.5,33.7),32.5 (28.7,37.5) and 30.0(27.5,36.2),respectively;and the median SDS scores were 32.5(27.5,39.7),36.2(30.3,45.0),37.5(35.0,45.0),respectively;and the differences in SAS and SDS scores among three groups were statistically significant (F=6.37,6.75,both P＜0.01).The SAS and SDS scores were not correlated with extra-esophageal symptoms in youth group.The SAS score was positively correlated with extra-esophageal symptoms in middle-aged group (r =0.19,P =0.009).The SAS and RDQ scores were positively correlated with extra-esophageal symptoms in aged group(r=0.26 and 0.23;P=0.005 and 0.003).Conclusions The incidence of extra-esophageal symptoms in middle-age group and aged group is high,the symptoms are severe and with anxiety and depression possibility.While unhealthy lifestyle and diet habits are more common in young patients.According to different age groups,risk factors should be adjusted.

Objective To investigate the effects of PM2.5 on tear film function and corneal epithelial structure in mice.Methods Totally 24 male BALB/c mice (24 eyes) were divided into two groups:group A (with PBS eye drops,n =12),group B (5 mg · mL-1 PM2.5 eye drop group,n =12).PBS and PM2.5 eye drop were given with four times per day for 7 consecutive days in right eye.Tear secretion level was measured with phenol red thread.Break-up time (BUT) of tear film was tested,and corneal fluorescein staining (FL) was scored before therapy and 1 day,4 days and 7 days after droppings and HE staining was performed 7 days after droppings,respectively.Results There was no significant difference in the tear secretion levels,BUT,FL between the groups A and B before treatment (all P ＞ 0.05).At 4 days,7 days after treatment with PM2.5,the mean differences of the group B showed all items significantly changed compared with those before treatment (all P ＜ 0.05).For the group A,there was no statistical change in tear secretion levels,BUT,FL at 7 days after treatment (all P ＞ 0.05).There were statistical differences in all items between group A and B at each time point (all P ＜ 0.05).At 7 days after therapy,the mean layers of corneal epithelial cells in the group A (4 ± 1) was significantly lower than that in the group B (7 ±l) (P ＜0.05).The group B showed that the whole corneal fluorescein staining obviously increased,and corneal epithelial cell layer was thickened.Conclusion PM2.5 can influence tears film function and damage the corneal epithelial structure in mice.

Objective To detect anti-M_2 autoantibody using recombinant BCOADC-E_2.Methods We purified recombinant BCOADC-E_2 by Ni~(2+)affinity chromatography column and then detect anti-M_2 autoan- tibody in the sera of patients with primary biliary cirrhosis(PBC)by Western blot test(WBT)and enzyme linked immunosorbent assays(ELISA).Results Among 60 sera from PBC patients,33 were positive,all of controls were negative.Conclusion The recombinant BCOADC-E_2 can be used to detect anti-M_2 autoanti- body specifically and sensitively.It is helpful for the diagnosis of PBC.

Objective To investigate the effect of songling xuemaikang(SL-xmk)pretreatment on the expression of matrix metalloproteinase-9(MMP-9)after focal cerebral ischemia-reperfusion in rats.Methods A total of 45 male Sprague-Dawley rats were randomly allocated into SL-xmk pretreatment,sham operation,and normal saline control group.Preventive gavage was per-formed for 8 weeks in rats using SL-xmk(937.50 mg/kg)suspension in the SLxmk pretreatment group(n = 15);the preventive gavage was performed in rats using the equal volume of normal saline in the sham operation(n = 15)and normal saline control(n = 15)groups.At the end of the pretreatment process,a model of middle cerebral artery occlusion(MCAO)in rats was induced by suture method for 2 hours and reperfusion for 24 hours.The effects of SL-xmk pretreatment on the neurologic deficit scores after transient MCAO,brain water content,and infarct volume in rats were observed.Immunohistochemical staining was used to detect the MMP-9 immunoreactive positive cells in ischemic brain tissue.Results The neurologjc deficit scores(1.21 ± 0.25 vs.2.37 ± 0.35,P = 0.000),the brain water content (76.24% ± 7.09% vs.88.78% ± 6.57%,P = 0.000),the percentage of infarct volume (22.62% ±2.17% vs.27.84% ±3.43%,P =0.000),and the numbers of MMP-9 positive cells(16.20 ± 2.17/mm vs.20.60 ± 2.71/mm,P = 0.000)were all significantly lower than those in the control group.Conclusions SL-xmk pretreatment may significantly inhibit the expression of MMP-9 in the brain tissue of focal cerebral ischemia-reperfusion rats and reduce brain water content and infarct volume.

Objective To purify and prokaryotically express the histone methyltransferase SET7.Methods The coding sequence of full length SET7 was amplified from breast library by PCR and cloned into the pGEX-KG vector.The correct recombinant plasmid was introduced into E.coli.The expressed protein was identified by SDS-PAGE.Results DNA sequencing indicated the SET7 was constructed.GST-SET7 fusion protein was identified by SDS-PAGE.Conclusion The prokaryotically expressed protein of GST-SET7 is obtained,which will falilitate further study of SET7 function.

AIM: To construct human Egr-1 promoter luciferase reporter system and study its activity induced by i-onizing radiation. METHODS: Egr-1 promoter was obtained by human genomic PCR and cloned into pGL3-basic vector. After transfection of recombinant plasmid into human tumor cells, the Egr-1 promoter activity induced by ionizing radiation was detected by luciferase reporter assay. RESULTS: The luciferasy reporter system of Egr-1 promoter was successfully constructed. The activity of Egr-1 promoter was substantially increased after different doses of IR and reached to the peak at the time point of 48h after IR. CONCLUSION: The Egr-1 promoter was constructed in this study showed IR inducible activity in tumor cells, laying foundation for the research of radiation, mediated gene therapy.

Objective To evaluate the performance of community health institutions of Pudong new district.Methods According to the criteria of the Ministry of Health of China,the performance evaluation system appropriate for local area was developed.A cross-sectional survey was conducted at 44 community health centers,and data was analyzed using descriptive statistics,correlation coefficients and multi-factor linear regression.Results The average score of total performance of these 44 community health centers was 78.53.The average scoring rate for institution management,public health service,basic medical care service,CTM service,and comprehensive satisfaction was 68.49％,89.09％,63.51％,87.80％,76.32％,respectively.Degree of informationization (0.477),regional location (0.331) and participating in medical consortia(-0.309)had significant impact on the total performance.Degree of informationization(0.302)and pilots for family doctors(0.301)had significant impact on the basic medical service performance.Conclusion There is a tremendous room for performance improvement for community health institutions in Pudong.Regional location and degree of informationization were the most crucial factors affecting the performance,irrelevant to institutional sizes.Proposals were raised for strengthening the construction of informationization,expanding pilots for family doctors,perfecting the mechanism of medical consortia.