Objective To customize the optimal plans for radioactive 125I seeds volumetric implants in selected regular target volumes.Methods 125I seeds were symmetrically and uniformly implanted into 3 spherical targets with the diameters of 1,2 and 3 cm and 7 ellipsoidal targets with the 3 dimensions of 1 cm×1 cm×2 cm,1 cm×1 cm×3 cm,1 cm×2cm×2cm,1 cm×2 cm×3 cm,1 cm ×3 cm×3 cm,2 cm×2 cm×3 cm and2 cm×3 cm×3 cm.The activity and inter-space of seeds were adjusted to obtain the conformal and uniform dose distribution,with the prescribed D90 (the dose delivered to 90％ of the targets) greater than 145 Gy.The inter-space of seeds was changed from 1 cm to 0.75 cm,to improve the conformity and uniformity of dose distribution.Plan quality was assessed using homogeneity index (HI),external index (EI) and conformal index (CI).The activity and number of seeds implanted were also recorded and compared.Results For the spherical target with the diameter of 1 cm,when seeds were implanted with the inter-space of 1 cm and 0.75 cm,the HI were 40.0％ and 55.9％,the EI were 98.3％ and 95.1％,the CI were 0.44 and 0.44,respectively.For the spherical target with the diameter of 3 cm and the target with the 3 dimensions of 1 cm × 2 cm × 2 cm,the implant with the inter-space of 1 cm provided better indices of HI,EI and CI than those with the inter-space of 0.75 cm.For the other targets,the implants with the inter-space of 0.75 cm provided better indices of EI and CI than those with the inter-space of 1 cm,although they displayed a little worse homogeneity in terms of HI.The activity per seed was 17.0-27.8 MBq and 30.0-58.8 MBq in the implants with the inter-spaces of 0.75 cm and 1 cm,respectively.2-10 more seeds were needed in the implants with the inter-space of 0.75 cm.Conclusions For the studied targets except the spherical targets with the diameter of 1 cm and 3 cm and the ellipsoidal target with the dimension of 1 cm × 2 cm × 2 cm,125I seeds implanted with the inter-space of 0.75 cm could provide more conformal dose distribution.It could be the better customized plans for uniformly spaced seed implantation.

In order to understand the academic attitude of medical postgraduates,a questionnaire survey was conducted among full-time postgraduate students.The impacts of working experience,gender,marriage status and source on the academic attitude were analyzed,and the improved suggestion and presumption for academic attitude were provided.

Objective To study the dosimetric characteristics of thermoluminescent dosimeter (TLD).Methods A total of 350 pieces of TLD 2000 type TLDs having the same sensitivity within ± 3.0％ were selected.The TLDs were irradiated to study the repeatability and dosage effect of TLDs by using 6 MV X-rays and 125I seeds.In order to study the dose response,the TLDs were irradiated at different dosages by using 137Cs (662 keV γ-rays),125I seeds and 6 MV X-rays.In order to study the energy response,the TLDs were exposed to the same dose,from 125I seeds,137Cs and X-rays(48,65,83,118,250 keV and 6 MV).Results The maximum deviations of the repeatability were 2.7％ and 4.0％ for 6 MV X-rays and 125I seeds,respectively,and there was no effect of dose rate observed.The dose response of TLDs to 137Cs and 125I seeds were linear.For 6 MV X-rays,the linear response was within the range of 0.74-10 Gy and non-linear range was beyond 10 Gy.The energy response to 125I seeds,48,65,83,118,250 keV and6 MV X-rays,relative to the energy response of 137Cs,were 1.70,1.25,1.08,0.99,0.91,0.96 and 1.22,respectively.Conclusions TLD 2000 has a good repeatability and linear dose response for 137Cs,125I seeds and 6 MV X-rays with no dose rate effects,but the dose response is energy dependent.

Objective This study aimed to assess the adherence to guideline-recommended therapies according to risk stratification in the management of acute coronary syndrome(ACS). Methods We analyzed 1,001 consecutive patients admitted with ACS. Patients were stratified using the GRACE risk score into low- and high-predicted risk of mortality at 6 months. We evaluated the use of hospital angiography,revascularization,and guideline-recommended medications between high and low-risk patients. Results High-risk compared to low-risk patients were less likely to underwent coronary angiography and/or revascularization during the hospitalization. The use of hospital-initiated pharmacotherapies was also lower in high-risk patients(P<0.05). Advanced age, increased creatinine level and higher GRACE score were independent predictors for failure to administer evidence-based therapies. Conclusion Patients with ACS at high risk of mortality were paradoxically less likely to undergo revascularization or receive medications according to guidelines. Better adherence to evidence-based therapies in high-risk patients may improve clinical outcome and quality of health care.

Objective To observe and evaluate the effects of metformin and pioglitazone on blood glucose,insulin,glucagon,β-cell function and insulin resistance among patients with diabetes and metabolic syndrome,so as to discuss the role of pancreatic α cells in pathogenesis of type 2 diabetes mainly caused by insulin resistance and the change of α-cell function after treatment.Methods A total of 60 patients diagnosed with diabetes and metabolic syndrome were selected in Beijing Chaoyang District Diabetes Center from April 2012 to April 2013 and divided with random number table into metformin group (treated with metformin 0.5 g orally thrice a day for 1 year,n =30) and pioglitazone group (treated with pioglitazone 15 mg orally once a day for 1 year,n =30).30 normal healthy people who had physical examination at the Center during the same period were enrolled into the control group,matched in age and gender with the intervention groups.The general condition of the 3 groups,and blood levels of glucose,insulin,and glucagon,insulin sensitivity index (ISI)-Matsuda,homeostasis model assessment of insulin resistance (HOMA-IR),β-cell function index (HOMA-β),1-phase index,2-phase index,and insulin secretion sensitivity index (ISSI) at baseline in the 3 groups and after treatment in the metformin group and the pioglitazone group were measured and calculated.Results Compared with the control group before treatment,the intervention groups as a whole had significantly higher fasting glucagon level [(146.22 ±25.41) pmol/L vs.(21.31 ±7.85) pmol/L,P =0.002] and area under curve (AUC) of glucagon [(469.84 ±13.12) pmol/(L · h) vs.(100.94 ± 7.73) pmol/(L · h),P =0.006].Compared with the results before treatment,the metformin group exhibited significantly reduced fasting glucose [(6.46 ± 1.38) mmol/L vs.(7.54 ± 0.43) mmol/L,P=0.031],fasting insulin [(119.22 ± 69.01) pmol/L vs.(139.38 ±71.13) pmol/L,P =0.042],fasting glucagon [(91.69 ±22.11) pmol/L vs.(142.81 ±24.56) pmol/L,P=0.029],AUC of glucose [(25.19 ± 1.31) mmol/ (L · h) vs.(32.68 ± 1.12) mmol/ (L · h),P =0.043],AUC of insulin [(468.65 ±20.10) pmol/ (L· h) vs.(786.32±21.37) pmol/ (L· h),P=0.017],and AUC of glucagon [(280.60±8.26) pmol/ (L · h) vs.(487.14±14.31) pmol/ (L · h),P=0.032];while the pioglitazone group after treatment also showed significantly decreased fasting glucose [(6.58 ±2.21) mmol/L vs.(7.68±0.59) mmol/L,P=0.028],fastinginsulin [(107.92±17.81) pmol/L vs.(144.66±74.43) pmol/L,P =0.033],fasting glucagon [(76.07 ±20.57) pmol/L vs.(148.34 ±28.94) pmol/L,P=0.025],AUC of glucose [(25.58 ±1.22) mmol/(L·h) vs.(35.07 ±1.38) mmol/(L· h),P=0.038],AUC of insulin [(435.54±19.30) pmol/ (L· h) vs.(854.75 ±20.61) pmol/(L·h),P=0.013],andAUCofglucagon [(223.43 ±5.83) pmol/ (L·h) vs.(458.55 ±12.96) pmol/ (L·h),P =0.026].The before-after-treatment differences were significantly smaller in the metformin group than in the pioglitazone group in terms of fasting insulin [(20.16 ± 2.98) mmol/L vs.(36.74 ± 2.88) mmol/L,P =0.011],fasting glucagon [(51.12 ± 3.67) pmol/L vs.(72.27 ± 4.58) pmol/L,P =0.016],AUC of insulin [(317.67 ±13.45) pmol/(L · h) vs.(419.21 ±15.44) pmol/(L · h),P=0.031] and AUC of glucagon [(206.54±9.66) pmol/(L· h) vs.(235.12±10.29) pmol/(L· h),P=0.046].Conclusions Glucagon in patients with diabetes and metabolic syndrome is higher than that in normal individuals.Metformin and pioglitazone can decrease the level of glucagon in patients with metabolic syndrome and diabetes as well as improve the glucose control,β-cell function and insulin resistance,suggesting improving effect of these two drugs on α-cell function.Pioglitazone manifests a stronger effect than metformin does.

BACKGROUND: Valsartan is an antagonist of angiotensin Ⅱ (Ang Ⅱ ) receptor. Many researches have proved that it can protect heart tissue. Val-PREST suggests that valsartan with a long-term administration can decrease restenosis rate in stent; however, effect of valsartan on restenosis rate of Chinese population is still unclear presently.OBJECTIVE: To evaluate the effect of oral valsartan for 6 months on patients with coronary heart disease (CHD) who undertook successful intervention therapy.DESIGN: Multicenter, double blind, randomized, and controlled evaluation and prospective design.SETTING: Beijing Friendship Hospital Affiliated to Capital Medical University; Beijing Anzhen Hospital Affiliated to Capital Medical University; Peking Union Hospital; People's Hospital of Peking University; Beijing Tongren Hospital Affiliated to Capital Medical University; Beijing Shijingshan Hospital; Beijing Fuxing Hospital Affiliated to Capital Medical University;Beijing Chuiyangliu Hospital.PARTICIPANTS: Eight three-grade A hospitals in Beijing participated in the study. Since December 2002 to October 2003, a total of 200 patients who underwent bare mental stent implantation were consented, but 196 patients were recruited in the end. All 196 patients were randomized into valsartan group (100 cases) and control group (96 cases).METHODS: Basic medicines in the two group included aspirin, clopidogrel, nitrides, statins, β-receptor antagonists, calcium channel antagonists, etc. Additionally, Patients in valsartan group were also given valsartan (Beijing Nuohua Pharmaceutical Co. Ltd., batch number: SD 34004) in a dosage of 80 mg a day. Both groups were followed-up once a month for total 6 months.MAIN OUTCOME MEASURES: ① Major adverse cardiac events within 6 months on clinics (death, non-fatal myocardial infarction, hospitalisation once more due to recurrent myocardial ischemia, and target vessel revascularization); ② Results of duplicated coronary angiography or exercise treadmill test (ETT) of partial patients within 6 months.RESULTS: ① Two patients (2%) in valsartan group were excluded in this study because of intolerance, so 194 patients were involved in the final analysis. ② No significant differences of baseline characteristics in terms of lesion type, the number of diseased vessels and the cardiac function were found between the two groups (P ＜ 0.05). ③ During the period of 6-month follow-up, one case died in control group. One acute myocardial infarction occurred in each group, whilst one case undertook target vessel revascularization in valsartan group. It was found that the proportion of recurrent cardiac events was lower in valsartan group than that in control group (11.2% vs. 15.6%). However, this difference did not reach the statistic significance. ④ During the period of 6-month duplicated contrast examination, one case had restenosis of in-stent in valsartan group. ⑤ The positive rate of exercise treadmill test (ETT) was lower in valsartan group (25.7%) than that in control group (36.4%), but there was no statistic difference.CONCLUSION: Six-month oral valsartan on patients with coronary heart disease who undertook successful intervention therapy can decrease the trend of recurrent cardiac events and positive rate of ETT.

Objective To re-evaluate the immunogenicity of meningococcal serogroups A and C polysaccharide vaccine among a healthy population of age 5 to 59.Methods Pre and post-vaccination ser-um samples were collected from the subjects involved in a randomized , controlled clinical trial conducted in 2005 at Hechi, Guangxi, China.Enzyme-linked immunosorbent assay (ELISA) was performed for the quan-titative detection of specific anti-capsule IgG antibody against meningococcal serogroups A and C in serum samples.Serum bactericidal assay ( SBA) was used to measure the bactericidal antibody activity against se-rougroups A and C bacterial strains .Results Geometric mean concentrations (GMCs) of specific anti-cap-sule IgG antibody were 23.66 μg/ml and 78.83 μg/ml for serogroup A (P<0.05), and 1.23 μg/ml and 51.25 μg/ml for serogroup C (P<0.05) in serum samples of pre and post-vaccination, respectively.Be-fore immunization , 99% of serum samples ( 97/98 ) showed serogroup A-specific IgG concentration ≥2μg/ml, which reached up to 100%(98/98) after vaccination (P>0.05).The percentage of serum sam-ples with serogroup C-specific IgG concentration ≥2 μg/ml rose from 20%to 99% after vaccination ( P<0.05).The ratio of positive serum samples with at least four times of increases in concentration of specific IgG against serogroup A and serogroup C after vaccine immunization were 34% and 100%, respectively . The rSBA geometric mean titers ( GMTs) for serogroups A and C in serum sample of post-vaccination were respectively elevated from 1164 to 5530 (P<0.05), and from 4 to 6225 (P<0.05).The percentage of se-rum samples with rSBA GMTs≥128 increased from 91% to 99% for serogroup A (P>0.05), and from 14%to 96%for serogroup C (P<0.05) after vaccination.The rSBA GMTs with at least four times of in-creases after vaccination were detected respectively in 53% and 100% of serogroups A and C vaccinated subjects.Pearson correlation coefficient between IgG concentration and rSBA GMTs was r=0.15 (pre) and r=0.23 (post) for serogroup A, and r=-0.14 (pre) and r=0.58 (post) for serogroup C (P<0.05). Conclusion This study has demonstrated an efficient and sustained immunogenicity with meningococcal sero -groups A and C polysaccharide vaccine as evidenced by the data from standardized assays of ELISA and SBA .

Objective To investigate the molecular size distribution and the structure of group B me-ningococcal capsular polysaccharides for the development of vaccines .Methods The molecular size distribution of group B meningococcal capsular polysaccharides was analyzed by chromatography on a Sepharose CL -4B col-umn.The molecular weight of repeat units were measured by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS).The structural characteristics of group B meningococcal capsular polysaccharides were analyzed by nuclear magnetic resonance ( NMR) based on the chemical shift of all charac-teristic protons by using group C meningococcal capsular polysaccharides and sialic acid as the controls .Results The KD value of group B meningococcal capsular polysaccharides extracted from 15 strains were ranged from 0.60 to 0.76.The molecular weight of repeat units was 284, which was identical to the theoretical value .The group B meningococcal capsular polysaccharides were 2→8 linked homopolymers of sialic acid lacking O-acetyl groups.Conclusion The group B meningococcal capsular polysaccharides had lower molecular weights , which might result in their poor immunogenicity .The structure of group B meningococcal capsular polysaccharides could be quickly and accurately analyzed by NMR technology .

Objective·To investigate the correlation of single nucleotide polymorphism (SNP) of complement factor H (CFH) gene with schizophrenia in Chinese Han population.Methods·The genotype,allele,and haplotype frequencies of 5 SNP loci (rs800292,rs 1061170,rs 10801555,rs 10922096 and rs2019727) in CFH gene were compared between 418 patients with schizophrenia (case group) and 655 normal people (control group) by SNaPshot technique.Results·All SNP loci were well genotyped in the subjects.Correlation analysis showed that rs1061170 locus allele frequency distribution difference between case group and control group was statistically significant (corrected P=0.045),while genotype and allele frequencies of other SNP loci were not significantly different (all corrected P＞0.05).The frequency of haplotype C-A-T-A-A (rs800292-rs1061170-rs10801555-rs10922096-rs2019727) in case group was different from that in control group (corrected P=0.013).Conclusion·The allele polymorphisms of rsl061170 and the haplotype C-A-T-A-A of rs800292-rs 1061170-rs 10801555-rs 10922096-rs2019727 may be associated with schizophrenia in Chinese Han population.

Objective To dynamically analyze the antibodies with regard to in vitro serum bacteri-cidal activity and the quantity of IgG in healthy adults received one dose of immunization with ACYW 135 me-ningococcal polysaccharide vaccine .To investigate the term of protection with polysaccharide vaccine and the correlation between bactericidal titer and IgG concentration .Methods Twenty healthy adults were given one dose of immunization with quadrivalent meningococcal polysaccharide vaccine .Serum samples were col-lected before and after vaccination at specific time points .Test for serum bactericidal activity ( SBA ) and quantitative ELISA were performed to detect bactericidal titers and IgG concentrations in serum samples .Re-sults Certain levels of antibodies against capsular polysaccharides of serogroup A , C, Y and W135 strains had already existed prior to immunization .Moreover, bactericidal titers against serogroup A , Y and W135 strains except serogroup C strain were relatively high .Specific IgG concentrations and bactericidal titers for all serogroup stains were significantly increased on day 15 after vaccination (P<0.05), and then sustained at a high level during a time period from day 30 to day 160.Both IgG concentrations and bactericidal titers dropped to the levels similar to that before preimmunization in about 3 years.No significant correlation was observed between bactericidal titers and IgG concentrations (r<0.3, P>0.05).However, a close correla-tion was demonstrated between GMTs and GMCs of serum samples (r>0.7, P<0.05).Conclusion The geometric mean titers ( GMTs) and geometric mean concentrations ( GMCs) of serum samples collected be-fore and after vaccination at different time points were reliable and consistent parameters for the evaluation of vaccine .The term of protection of quadivalent meningococcal polysaccharide vaccine was about 3 years upon a single dose of immunization .