Optimized new Shengmai powder inhibits myocardial fibrosis in heart failure by regulating the rat sarcoma/rapidly accelerated fibrosarcoma/mitogen-activated protein kinase kinase/extracellular regulated protein kinases signaling pathway.

OBJECTIVE: Exploring the effect of Optimized New Shengmai powder (, ONSMP) on myocardial fibrosis in heart failure (HF) based on rat sarcoma (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase kinase (MEK)/extracellular regulated protein kinases (ERK) signaling pathway. METHODS: Randomized 70 Sprague-Dawley rats into sham (n = 10) and operation (n = 60) groups, then established the HF rat by ligating the left anterior descending branch of the coronary artery. We randomly divided the operation group rats into the model, ONSMP [including low (L), medium (M), and high (H) dose], and enalapril groups. After the 4-week drug intervention, echocardiography examines the cardiac function and calculates the ratios of the whole/left heart to the rat's body weight. Finally, we observed the degree of myocardial fibrosis by pathological sections, determined myocardium collagen (COL) I and COL Ⅲ content by enzyme-linked immunosorbent assay, detected the mRNA levels of COL I, COL Ⅲ, α-smooth muscle actin (α-SMA), and c-Fos proto-oncogene (c-Fos) by universal real-time, and detected the protein expression of p-RAS, p-RAF, p-MEK1/2, p-ERK1/2, p-ETS-like-1 transcription factor (p-ELK1), p-c-Fos, α-SMA, COL I, and COL Ⅲ by Western blot. RESULTS: ONSMP can effectively improve HF rat's cardiac function, decrease cardiac organ coefficient, COL volume fraction, and COL I/Ⅲ content, down-regulate the mRNA of COL I/Ⅲ, α-SMA and c-Fos, and the protein of p-RAS, p-RAF, p-MEK1/ 2, p-ERK1/2, p-ELK1, c-Fos, COL Ⅰ/Ⅲ, and α-SMA. CONCLUSIONS: ONSMP can effectively reduce myocardial fibrosis in HF rats, and the mechanism may be related to the inhibition of the RAS/RAF/MEK/ERK signaling pathway.

Dosimetric analysis of the optimization algorithm for intracavitary/interstitial brachytherapy of cervical cancer / 中华放射医学与防护杂志

Objective:To provide a basis for selecting the optimization method for intracavitary/interstitial brachytherapy (IC/ISBT) of cervical cancer by comparing graphical optimization (GO), inverse planning simulated annealing (IPSA), and hybrid inverse planning optimization (HIPO) using dosimetric and radiobiological models.Methods:This study selected 65 patients with cervical cancer who were treated with image-guided IC/ISBT. The afterloading therapy plans for these patients were optimized using GO, IPSA, and HIPO individually, with a prescription dose high-risk clinical target volume (HRCTV) D90 of 6 Gy. The non-parametric Friedman test and the non-parametric Wilcoxon rank test were employed to analyze the differences in duration, dose-volume parameters, and radiobiology between the three types of optimized plans. Results:Inverse planning optimization (IPSA: 46.53 s; HIPO: 98.36 s) took less time than GO (135.03 s). In terms of gross target volume (GTV) dose, the high-dose irradiation V150% (53.66%) was slightly higher in the HIPO-optimized plans, while the V200% (30.29%) was higher in the GO-optimized plans. The GO-optimized plans had a higher conformity index (CI; 0.91) than other plans, showing statistically significant differences. Compared with other plans, the HIPO-optimized plans showed the lowest doses of D1 cm 3 and D2 cm 3 at bladders and rectums and non-statistically significant doses at small intestines ( P > 0.05). In terms of the equivalent uniform biologically effective dose (EUBED) for HRCTV, the HIPO-optimized plans showed a higher value (12.35 Gy) than the GO-optimized plans (12.23 Gy) and the IPSA-optimized plans (12.13 Gy). Moreover, the EUBED at bladders was the lowest (2.38 Gy) in the GO-optimized plans, the EUBED at rectums was the lowest (3.74 Gy) in the HIPO-optimized plans, and the EUBED at small intestines was non-significantly different among the three types of optimized plans ( P = 0.055). There was no significant difference in the tumor control probability (TCP) predicted using the three types of optimized plans ( P > 0.05). The normal tissue complication probabilities (NTCPs) of bladders and rectums predicted using the HIPO-optimized plans were lower than those predicted using the GO- and IPSA-optimized plans( χ2 = 12.95-38.43, P < 0.01), and the NTCP of small intestines did not show significant differences ( P > 0.05). Conclusions:Among the three types of optimization algorithms, inverse optimization takes less time than GO. GO-optimized plans are more conformal than IPSA- and HIPO-optimized plans. HIPO-optimized plans can increase the biological coverage dose of the target volume and reduce the maximum physical/biological exposure and NTCP at bladders and rectums. Therefore, HIPO is recommended preferentially as an optimization algorithm for IC/ISBT for cervical cancer.

Dose distribution prediction in cervical cancer brachytherapy based on 3D U-net / 中华放射医学与防护杂志

Objective:To establish a three-dimensional (3D) U-net-based deep learning model, and to predict the 3D dose distribution in CT-guided cervical cancer brachytherapy by using the established model.Methods:The brachytherapy plans of 114 cervical cancer cases with a prescription dose of 6 Gy for each case were studied. These cases were divided into training, validation, and testing groups, including 84, 11, and 19 patients, respectively. A total of 500 epochs of training were performed by using a 3D U-net model. Then, the dosimetric parameters of the testing groups were individually evaluated, including the mean dose deviation (MDD) and mean absolute dose deviation (MADD) at the voxel level, the Dice similarity coefficient (DSC) of the volumes enclosed by isodose surfaces, the conformal index (CI) of the prescription dose, the D90 and average dose Dmean delivered to high-risk clinical target volumes (HR-CTVs), and the D1 cm 3 and D2 cm 3 delivered to bladders, recta, intestines, and colons, respectively. Results:The overall MDD and MADD of the 3D dose matrix from 19 cases of the testing group were (-0.01 ± 0.03) and (0.04 ± 0.01) Gy, respectively. The CI of the prescription dose was 0.70 ± 0.04. The DSC of 50%-150% prescription dose was 0.89-0.94. The mean deviation of D90 and Dmean to HR-CTVs were 2.22% and -4.30%, respectively. The maximum deviations of the D1 cm 3 and D2 cm 3 to bladders, recta, intestines, and colons were 2.46% and 2.58%, respectively. The 3D U-net deep learning model took 2.5 s on average to predict a patient′s dose. Conclusions:In this study, a 3D U-net-based deep learning model for predicting 3D dose distribution in the treatment of cervical cancer was established, thus laying a foundation for the automatic design of cervical cancer brachytherapy.

Study of robust optimization in brachytherapy / 中华放射肿瘤学杂志

Objective:To evaluate the application value of robost optimization of brachytherapy for cervical cancer.Methods:Twenty patients who completed radical treatment were recruited in this study. The dose volume histogram (DVH) parameters were statistically compared between the conventional and robust optimization plans, and the robustness between the conventional and robust optimization plans was evaluated using DVH and DVH bands. The robust optimization method utilized the worst dose distribution to consider the dose in the presence of uncertainties. In each optimization iteration, the dose distributin when the radioactive source shifted along the X, Y, and Z directions (±2 mm), and the dose distribution when the radioactive source was not shifted were calculated. The worst dose distribution for each voxel was the lowest dose in the target and the highest dose outside the target under all circumstances. The iterative objective function was calculated by the worst dose distribution.Results:In the scenario of no shifting of radioactive source position, the mean value of robust optimization was significantly lower and that of V 150% was significantly higher than those of conventional optimization (both P<0.05). When considering the shifting of radioactive source position, the worst dosimetric parameters of multiple dose distributions were statistically compared. The mean HR-CTV D 100% values did not significantly differ between the robust and conventional optimization plans, whereas the mean D 90% value (range: 0.02-0.03 Gy) of robust optimization was significantly higher than that of conventional optimization ( P<0.05). Robust optimization increased the D 2cm 3 of the bladder and small intestine, and the rectum dose was increased with the shifting of the radioactive source position in the robust optimization. The DVH bands did not significantly differ between the conventional and robust optimization plans for all patients. Conclusions:Robust optimization based on the worst dose distribution fails to significantly improve the robustness of brachytherapy for cervical cancer. Alternative methods are required to minimize the dosimetric effect of uncertainties in brachytherapy.

The effect of bulk electron density on the dose accuracy of treatment planning for postoperative cervical cancer / 中华放射医学与防护杂志

Objective:To study the impact on dose accuracy for the treatment planning by manually assigning accurate electron density for CT image-based tumor tissues and organs at risk.Methods:Twenty cases of retrospective postoperative cervical cancer radiotherapy plans were selected. The body electron density of the corresponding organs was derived from the ICRU 46 report and assigned in the treatment planning system (Monaco5.11, Sweden), including the bladder, rectum, intestine, kidney, spinal cord, femoral head, and ilium. The original plans were double-arc volumetric modulated arc therapy plan (360° VMAT), using Monte Carlo algorithm, the calculation grid was 0.3 cm × 0.3 cm × 0.3 cm, and the minimum subfield width was 0.6 cm. Keep the original plan fluence unchanged and recalculate the dose to generate a new plan. The two-dimensional dose distribution and dose-volume histogram (DVH) were used to compare the differences between the two plans. The difference was compared between the two group plans by using the dosimetry parameters and DVH two dimension curve.Results:For the planning of assigning bulk electron density (Plan RED), the deviation of the patient′s target dose parameters and the original plan (Plan ref) was <2%, and the average deviation of all target regions D2, D98, Dmean was < 0.7%, only 2 of the 180 data were between 2% and 3%. The average deviation of V20, V30, D1 cm 3, Dmean of the bladder, rectum, and small intestine, the original Plan ref was less than 0.6%, and 4 out of 240 data had values > 2%. Plan RED′s average hop count was 0.9% higher than Plan ref, and the total number of subfields remains unchanged. The planned dose generated by manually assigning the electron density in Plan RED was higher than that in Plan ref, but met the clinical requirements. The two-dimensional curves of the DVH diagram for targets and OARs almost completely overlapped, and there was no obvious difference in the dose distribution diagram of the same cross section. The statistical result of all parameters showed that the difference in planned dose parameters between the two groups was not statistically significant( P>0.05). Conclusions:The overall deviation of dose accuracy between Plan RED and Plan ref is <2%, which meets the clinical requirements and provides a reference for realizing MRI-only treatment planning.

Recommendations for public health protection against flood disaster / 中华预防医学杂志

Flood disaster is one of the most serious natural disasters in the world, and it could pose an inestimable impact on the affected people. Based on existing laws, regulations, and emergency manuals in China, extensive literature review, epidemiological and related protection evidence, and expert consultation, this study analyzed different health risk factors of flood disaster and proposed a multi-stage, multi-population, and multi-phase comprehensive protection measures for the public in the perspective of pre-event prevention, in-event intervention and post-event rescue strategy, which could provide a scientific basis for improving the level of public health protection against the flood disaster and corresponding health outcomes.

A study of an independent dose verification software for brachytherapy / 中华放射肿瘤学杂志

Objective@#To report an implementation method and results of an independent brachytherapy dose verification software (DVS).@*Methods@#The DVS was developed based on Visual C+ + and the modular structure design was adopted. The DICOM RT files exported from the treatment planning system (TPS) were automatically loaded into the DVS. The TG-43 formalism was employed for dose calculation. Six cervical cancer patients who underwent brachytherapy were retrospectively selected to test the DVS. Different applicators were utilized for each patient. Dosimetric parameters and γ analysis (0.1cm, 5%) were used to evaluate the dose difference between the DVS and the TPS.@*Results@#Compared with the TPS dose, the γ pass rates of the doses calculated by the DVS were higher than 98%. For CTV, the dosimetric differences were less than 0.29% and 0.53% for D100% and D90%. For bladder, rectum and sigmoid, the agreement of D0.1cm3, D1cm3 and D2cm3 within a 0.5% level.@*Conclusion@#With minimal human-computer interactions, the DVS can verify the accuracy of dose calculated by TPS for brachytherapy.

A verification study of Offset values of different applicators in afterloading brachytherapy / 中华放射肿瘤学杂志

Objective@#To investigate the Offset values of different applicators in afterloading brachytherapy.@*Methods@#Six types of applicators were selected in this study which included stainless steel interstitial needle (Part#083.062), proguide round needle (Part#189.608), proguide sharp needle (Part#189.601), vaginal multi-channel applicator (Part#110.800), fletcher CT/MR applicator (Part#189.745) and henschke titanium applicator (Part#110.437). According to the sources imaging in the fluorography film, the distance of applicators between the first dwell position and the top could be measured. Marker was pasted on the surface of applicator corresponding to the first dwell position. And then the applicator was put into the pelvic phantom for a CT scan. During applicator reconstruction in the treatment planning system, the Offset values of all applicators could be acquired through adjusting the value of offset to superimpose the first dwell and the marker images. On account of the density of plastic material applicators were similar to human tissues, it was difficult to reconstruct the top of the applicator. With the help of stopper or simulation source, the value of offset could be acquired for plastic material applicators. Based on the measurement results, the differences were analyzed among different applicators.@*Results@#The Offset values significantly differed among various applicators. The Offset value for stainless steel interstitial needle was -11.4 mm, -4.1 mm for proguide round needle, -3.5 mm for proguide sharp needle, 0 mm or -5.0 mm for vaginal multi-channel applicator, -6.5 mm for fletcher CT/MR applicator and -7.5 mm for henschke titanium applicator, respectively.@*Conclusion@#To adapt to the rapid development of precise radiotherapy, it is necessary to verify the Offset value in afterloading brachytherapy.

An inverse dose optimization algorithm for three-dimensional brachytherapy / 中华放射肿瘤学杂志

Objective:To explore an implementation method and results of an inverse dose optimization algorithm (gradient-based planning optimization, GBPO) in three-dimensional brachytherapy.Methods:A standard quadratic objective function was used in the GBPO. The optimization code of GBPO was performed based on LBFGS (Limited memory Broyden Fletcher Goldberg Shanno). Seven cervical cancer patients using different applicators and 15 cervical cancer patients using the Fletcher applicator (Nucletron part#189.730) were retrospectively analyzed. The plan quality of GBPO was firstly assessed by isodose lines, then dose-volume histogram (DVH) parameters of CTV(D 100%, V 150%) and organs at risk(D 0.1cm 3, D 1.0cm 3, D 2.0cm 3) were used to evaluate the difference among the GBPO, IPSA and Graphic plans. Results:For the 7 patients using different applicators, GBPO could optimize the conformal dose distribution, and the DVH parameters of the target and organs at risk were basically the same among the GBPO, IPSA and Graphic plans. For 15 patients using the Fletcher applicator, the difference in DVH parameters between the GBPO and IPSA plans was not statistically significant. There was no remarkable difference in the DVH parameters between the GBPO and Graphic plans, but the D 100% of the GBPO plan was significantly higher ( P<0.01), and the V 150% was significantly lower ( P<0.01) than that of the Graphic plan. Conclusions:The quality of the GBPO plan is similar to that of the IPSA plan in terms of target coverage and organ protection. The inverse dose optimization algorithm GBPO can be integrated into a three-dimensional brachytherapy treatment planning system.

A study of an independent dose verification software for brachytherapy / 中华放射肿瘤学杂志

Objective To report an implementation method and results of an independent brachytherapy dose verification software (DVS).Methods The DVS was developed based on Visual C++ and the modular structure design was adopted.The DICOM RT files exported from the treatment planning system (TPS) were automatically loaded into the DVS.The TG-43 formalism was employed for dose calculation.Six cervical cancer patients who underwent brachytherapy were retrospectively selected to test the DVS.Different applicators were utilized for each patient.Dosimetric parameters and γ analysis (0.1 cm,5％) were used to evaluate the dose difference between the DVS and the TPS.Results Compared with the TPS dose,the γ pass rates of the doses calculated by the DVS were higher than 98％.For CTV,the dosimetric differences were less than 0.29％ and 0.53％ for D100％ and D90％.For bladder,rectum and sigmoid,the agreement of D0.1cm3,D1cm3 and D2cm3 within a 0.5％ level.Conclusion With minimal human-computer interactions,the DVS can verify the accuracy of dose calculated by TPS for brachytherapy.

A verification study of Offset values of different applicators in afterloading brachytherapy / 中华放射肿瘤学杂志

Objective To investigate the Offset values of different applicators in afterloading brachytherapy.Methods Six types of applicators were selected in this study which included stainless steel interstitial needle (Part#083.062),proguide round needle (Part#189.608),proguide sharp needle (Part# 189.601),vaginal multi-channel applicator (Part # 110.800),fletcher CT/MR applicator (Part # 189.745)and henschke titanium applicator (Part#110.437).According to the sources imaging in the fluorography film,the distance of applicators between the first dwell position and the top could be measured.Marker was pasted on the surface of applicator corresponding to the first dwell position.And then the applicator was put into the pelvic phantom for a CT scan.During applicator reconstruction in the treatment planning system,the Offset values of all applicators could be acquired through adjusting the value of offset to superimpose the first dwell and the marker images.On account of the density of plastic material applicators were similar to human tissues,it was difficult to reconstruct the top of the applicator.With the help of stopper or simulation source,the value of offset could be acquired for plastic material applicators.Based on the measurement results,the differences were analyzed among different applicators.Results The Offset values significantly differed among various applicators.The Offset value for stainless steel interstitial needle was-11.4 mm,-4.1 mm for proguide round needle,-3.5 mm for proguide sharp needle,0 mm or-5.0 mm for vaginal multi-channel applicator,-6.5 mm for fletcher CT/MR applicator and-7.5 mm for henschke titanium applicator,respectively.Conclusion To adapt to the rapid development of precise radiotherapy,it is necessary to verify the Offset value in afterloading brachytherapy.

A study on a method for restricting dwell time variation in brachytherapy plan optimization / 中华放射医学与防护杂志

Objective:To report an implementation method and result of an inverse dose optimization algorithm (GBPO) that can control the dwell time variation in three-dimensional brachytherapy.Methods:The GBPO used a quadratic objective function. A dwell time modulation item was added to the objective function to restrict the dwell time variation, and a DTMF (dwell time modulation factor) was used to adjust the dwell time variation. A retrospective study was made of 15 cervical cancer patients treated using the Fletcher applicator. The relationship between the DTMF and dwell time deviation was analyzed. Dose-volume histogram (DVH) parameters of HR-CTV ( D100%, V150%) and organs at risk (OARs) ( D0.1 cm 3, D1 cm 3, D2 cm 3) were used to evaluate the difference between the GBPO plans and the commercial treatment plan system (using the IPSA algorithm) plans. Results:When the DTMF was less than 20, the dwell time deviation decreased quickly. However, after the DTMF increased to 100, and the dwell time deviation had no remarkable change. The D100% of GBPO plan was higher than that of IPSA plan (3.63±0.36 vs. 3.53±0.34, t=2.45, P<0.05), and the difference in other dosimetric parameters between the GBPO plans and the IPSA plans was not statistically significant ( P>0.05). Conclusions:The method reported in this study to control the dwell time variation was feasible. The GBPO plans have a comparable quality as the IPSA plans for the studied cervical cancer cases. The GBPO algorithm could be integrated into a three-dimensional brachytherapy treatment planning system.

A clinical study of endoscopic balloon dilation in treatment of esophageal stenosis after neonatal esophageal atresia surgery / 中华消化内镜杂志

Objective To explore the feasibility and efficacy of endoscopic balloon dilation in treatment of esophageal stenosis caused by operation of congenital esophageal atresia. Methods A retrospective analysis was performed on data of 218 children with type Ⅲ esophageal atresia, who underwent surgery in Zhengzhou Children' s Hospital from January 2009 to December 2017. The occurrence of postoperative complications and efficacy of endoscopic balloon dilation in treatment of esophageal stenosis was analyzed. Results Among the 218 patients with congenital esophageal atresia, 92 were type Ⅲa and 126 were type Ⅲb. Postoperative anastomotic leakage occurred in 46 cases (21. 1％), including 29 (31. 5％) of type Ⅲa and 17 (13. 5％) of type Ⅲb. Postoperative anastomotic stenosis occurred in 53 cases (24. 3％), including 29 ( 31. 5％) of type Ⅲa and 24 ( 19. 0％) of typeⅢb. The incidence of anastomotic leakage and anastomotic stenosis in different types was significantly different (χ2=10. 383, P=0. 001; χ2=4. 497, P=0. 034). The 53 cases of anastomotic stenosis underwent 123 times of endoscopic balloon dilation, with mean time of 3. 5±1. 6, and were finally clinically recovery. No esophagus perforation occurred. Among them, 29 cases of type Ⅲa underwent 73 times with mean of 4. 0±1. 8, and 24 cases of type Ⅲb underwent 50 times with mean of 2. 5±0. 7. The difference between the two types was statistically significant (t=-4. 053, P=0. 027). Conclusion Children with type Ⅲa esophageal atresia has a higher incidence of anastomotic stenosis and leakage, and more times of esophageal dilation. Endoscopic balloon dilation is safe and effective in treatment of esophageal stenosis after surgery for patients with congenital esophageal atresia.

Suggestions on environmental and health work from Health Environment Promotion Campaigns / 中华预防医学杂志

The Health Environment Promotion Campaigns (HEPCs) focus on the major environmental health issues and relevant factors of concern among the general public, and promote the achievement of the national health goal. Based on the summary and analysis of the background, key indicators, specific actions in different domains of the HEPCs, this paper proposes suggestions for scientifically implementing HEPCs from five aspects, namely, formulating implementation plans, establishing pilot areas, building comprehensive service platforms, improving the health literacy of residents and strengthening the development of protection technologies and standards.

Achievements and prospects on environmental health and sanitary engineering in China / 中华预防医学杂志

According to different epochs and development needs, a series of practices on environmental health and sanitary engineering were carried out, which played significant roles in promoting national economic and social developments and protecting the public health. This paper reviewed the main achievements in the past 70 years infields of patriotic health campaign, water sanitation and toilet improvement in rural areas, surveillance and investigation, health standard system, sanitary engineering equipment, stove improvement etc., and then proposed several prospects in the future.

Tat-based cell-cell fusion method for screening HIV-1 fusion inhibitors / 生物工程学报

An HIV-1 cell-cell fusion system was developed to screen HIV-1 entry inhibitors that block cell-cell fusion. In this system, the pEGFP-Tat plasmid was constructed and cotransfected into effector cells (HEK-293T) with HIV-1 envelope plasmid. TZM-bl cell, a genetically engineered cell line that expresses CD4, CXCR4, CCR5 as well as Tat-inducible β-galactosidase and luciferase reporter gene, was used as target cell. Thus, the co-culture of target cells and effector cells allows the cell fusion via Env and the activity of the fusion inhibitor can be quantified by measuring the reporter protein expression. The experimental parameters were optimized and 11 anti-HIV-1 agents including CCR5 antagonist maraviroc, reverse transcription inhibitor zidovudine (AZT) and integrase inhibitor raltegravir were tested. The result showed that the system exhibited high specificity and sensitivity. Two of eight tested anti-HIV-1 agents were found to block the cell-cell fusion. The system is suitable for efficient screening of HIV-1 cell-cell fusion inhibitors.

Effect and research progress of respiratory motion on intensity-modulated proton therapy / 中华放射肿瘤学杂志

Compared with intensity-modulated photon therapy, intensity-modulated proton therapy has significant dose advantages. However,the dose gradient of proton Bragg peak is relatively high,and the proton therapy is likely to be affected by range uncertainties,setup uncertainties and antonymic changes,etc. The difference between the planning dose and actual dose caused by respiratory motion hinders the widespread use of intensity-modulated proton therapy in thoracic cancers. In this paper,research progress on the effect of respiratory motion on intensity-modulated proton therapy and how to reduce the effect were summarized,aiming to provide reference for clinicians and researchers.

Monte Carlo dosimetric study of the GZP 60 Co brachytherapy source with stainless steel applicator / 中华放射肿瘤学杂志

Objective To evaluate the effect of stainless steel applicator on dose distribution in GZP 60 Co brachytherapy source and to obtain the dosimetric parameters of the 60 Co source with stainless steel applicator. Methods Geant4 was employed to obtain the mean adsorption dose of the 60 Co brachytherapy source in the range of 0-10 cm, and the dosimetric parameters were calculated according to the formula proposed by AAPM reports TG43 and TG43U1. The 60 Co source was located in the center of a sphere water phantom with a radius of 30 cm. Results For channel 1 and 2 of GZP 60 Co source, the results of Λ with stainless steel applicator were 1. 014 cGyh-1 U-1( with a difference of 0. 5％ compared with non-applicator) , the results of Λ with stainless steel applicator for channel 3 were 0. 998 cGyh-1 U-1 ( with a difference of 0. 1％ compared with non-applicator) . The radial dose function in the range of 0. 5-10. 0 cm in a longitudinal direction was calculated and the fitting formula for the function was obtained. The polynomial function for the radial dose function and the anisotropy function with a of 0°-175° and an r of 0. 5-10. 0 cm were obtained. Conclusion The dosimetric parameters of the 60 Co source with stainless steel applicator are obtained, which provide more accurate reference data for clinical application. In clinical practice, the effect of stainless steel applicator on dose distribution should be considered.

Effects of Simvastatin on myocardial apoptosis and oxidative stress mechanism in immature rabbits with chronic heart failure / 中华实用儿科临床杂志

Objective To observe the effects of Simvastatin on myocardial apoptosis and oxidative stress mechanism in immature rabbits with chronic heart failure.Methods Thirty-six male New Zealand big-eared immature rabbits were randomly divided into 3 groups:Adriamycin(ADR) ± Simvastatin group(ADR-s group,n =12),in which ADR(1.5 mg/kg) received injection via the auricular vein of rabbits weekly,and the rabbits received oral Simvastatin [1.5 mg/(kg · d)] simultaneously for 12 weeks;ADR group (n =12),in which the rabbits received ADR like ADR-S group,and 9 g/L saline instead of Simvastatin;control group (CON group,n =12),which received the same amount of 9 g/L saline.Echocardiography examination was performed in 13th week.Myocardial fibrosis degree was detected by using MASSON staining,and the myocardial apoptosis was detected by using terminal deoxynucleotidyl transferase dUTP nick end labeling.Colorimetric method was used to detect the myocardial concentration superoxide dismutase (SOD) and malondialdehyde (MDA).Enzyme-linked immunosorbent assay was used to detect serum B-type brain natriuretic peptide (BNP) level.Results (1) In CON group,the immature rabbits were all alive.Four rabbits died in ADR group,and the survival rate was 66.7％,while 2 rabbits died in ADR-s group,and the survival rate was 83.3％.(2)Compared with CON group,the left ventricular end diastolic diameter (LVEDd) and left ventricular end systolic diameter (LVESd) in ADR-s group and ADR group increased [(11.90 ±1.09) mm,(ll.34 ±0.92) mm vs.(10.73 ±0.48) mm;(9.80 ±0.88) mm,(8.47 ± 1.23) mm vs.(7.31 ±0.36) mm];left ventricular fractional shortening(LVFS) and left ventricular ejection fraction(LVEF) decreased [(17.65 ± 1.70)％,(22.58 ± 2.19)％ vs.(31.79 ± 2.58) ％;(41.35 ± 3.19) ％,(49.17 ± 3.53) ％ vs.(64.34 ± 3.97) ％],and all the differences were significant(all P ＜ 0.05);LVEDd and LVESd in ADR-s group were lower than those of ADR group,while LVEF and LVFS in ADR-s group were higher than those of ADR group,and the differences were significant(all P ＜ 0.05).(3)MASSON staining:compared with ADR group,there was less myocardial cell hyperplasia of fibrous tissue in ADR-s group.(4) Compared with CON group,the apoptosis index was higher in ADR and ADR-s group [(34.25 ±11.13) ％,(24.00 ±6.85)％ vs.(16.58 ± 5.34)％],but ADR-s group had less than ADR group,and the differences were significant (all P ＜ 0.05).(5) Compared with ADR group,SOD activity of ADR-s group was higher [(13.40 ± 2.68) kU/L vs.(10.66 ± 2.99) kU/L],but MDA content was lower [(5.67 ± 1.36) μmol/mg vs.(7.08 ±0.98) μmol/mg],and the differences were significant (all P ＜0.05).(6) Serum BNP level in ADR group and ADR-s group was higher than that of the CON group[(33.28 ±9.58) μg/L,(26.71 ±6.72) μg/L vs.(13.56 ±2.82) μg/L],while was higher in ADR group than that of ADR-s group,and the differences were significant (all P ＜ 0.05).Conclusions Simvastatin can protect cardiac function of immature rabbits with chronic heart failure.The possible mechanism may be the up-regulation of myocardial SOD activity,reduction of cell lipid peroxidation and inhibition of myocardial apoptosis.

MRS application in temporal lobe epilepsy without hippocampal sclerosis / 中国医学影像技术

Objective To investigate the application value of MRS in temporal lobe epilepsy (TLE) without hippocampal sclerosis.Methods A retrospective study was conducted in 23 unilateral TLE patients (TLE group) with absence of hippocampal sclerosis and 20 age-matched normal control subjects (control group).All of them underwent conventional MRI and MRS.N-acetyl aspartate (NAA)/creatine (Cr),choline (Cho)/Cr ratios of bilateral hippocampus in 2 groups were analyzed.Eleven of 23 patients underwent surgical treatment,pathological findings and surgical outcomes were evaluated.Results The NAA/Cr ratios of ipsilateral hippocampus significantly decreased compared with that in the contralateral hippocampus (t=-7.97,P＜0.001) and the control group (t=-9.96,P＜0.001).There was no significant difference between the contralateral hippocampus in patients and the control group (t=-1.21,P=0.12).The Cho/Cr ratios of ipsilateral hippocampus in TLE had no significant difference compared with contralateral hippocampus (t=0.50,P=0.31) and the control group (t=-0.59,P=0.28).The pathological findings of the 11 patients who underwent temporal lobe resection indicated small amounts of neuronal loss and unobvious gliosis.Conclusion MRS is helpful in clinical practice to lateralize and localize the epileptogenic foci in the absence of hippocampal sclerosis in patients with TLE.