OBJECTIVE Influence of irradiation and phenytoin sodium on modulatory activities of wound fluid on proliferation of fibroblasts and collagen synthesis was studied. METHODS The male Wistar rats were used in this study. The rats were divided into irradiated and non-irradiated groups, and in each of them it was subdivided into phenytoin group and control. A 7 cm long incisional wound was made on the back of each rat, in which a polyvinyl alcohol sponge (PVAS) with a size of 1.0 cm x 0.4 cm was implanted into the wound and the wound was sutured up. The PVAS was prepared by rinsing in running water over night and then was boiled for 30 minutes. Before implantation, the sponge was immersed in phenytoin sodium solution (10 mg/l ml) or normal saline (as control). From each wound the wound fluid and fibroblasts were collected. The methods of incorporation of 3H were adopted to assess the proliferation of fibroblasts and synthesis of collagen. RESULTS It was shown that proliferation of fibroblasts and collagen synthesis were stimulated by wound fluid remarkably on 5 to 8 days after wounding, and that 6 Gy to total-body irradiation wound decrease this effect. It was also noted that topical phenytoin sodium increased the modulatory activity of wound fluid irrespective of being irradiated or not. CONCLUSION It could be drawn that, after total-body irradiation, stimulation of hyperplasia of fibroblasts and collagen synthesis by wound fluid was markedly lowered indicating the total-body irradiation resulted in changes of local conditions of the wound which was unbenefitted to repair of tissue cells, while phenytoin sodium could enhance the stimulating action of wound fluid on proliferation of fibroblasts and synthesis of collagen which was beneficial to wound healing.
ObjectiveTo investigate the influence of 70 kV low-dose CT perfusion technique on brain CT perfusion parameter maps and image quality. MethodsRetrospective analysis of all patients who underwent CT perfusion of brain between October 2013 and February 2014 was carried out. The patients were randomly divided into two groups according to diTherent CT examination dose: group A (80 kV, 200 mAs) and group B (70 kV, 200 mAs). All patients were scanned on a dual-source-CT (Siemens Definition Flash). Fifteen normal subjects without brain diseases in each group were selected to be studied. Region of interest (ROI) with an area of 80 mm2 was placed in the nucleus, putamen, thalamus, periventricular white matter of the frontal lobe and temporo-occipital area, and the parameters in the ROI including cerebral blood flow, cerebral blood volume, mean transit time and time to peak were detected. The carrierto-noise ratio and signal-to-noise ratio of thalamus and periventricular white matter of the frontal lobe were contrasted. The image quality of perfusion was assessed by two senior radiologists using 5 point system for blind assessment (5=best, 1=worst). The measurement of radiation dose was studied through effective dose, volume CT dose index (CTDIVOL) and dose length product (DLP). Statistical analysis was performed by independent sample t test. ResultsThere was no significant difference between group A and group B in brain CT perfusion parameters (P>0.05). There was no significant diTherence in image quality between the two groups in the objective and subjective assessment (P>0.05). In comparison with group A, the measured effective dose, CTDIVOL and DLP for group B decreased by 35%. ConclusionThere was no significant influence on the brain CT perfusion parameters and image quality using 70 kV tube voltage, and radiation dose is decreased obviously.
Objiective To observe the changes of angioarchitecture of the optic disc in cats eyes after radial optic neurotomy (RON). Methods Ten healthy adult cats underwent unilateral RON randomly in 10 eyes as an operative group in this trial, and the fellow eyes (10 eyes) were as the control group. The colophony samples of vascular angioarchitecture of 20 eyes were made 90 days after RON and scanning electron microscope was used for the observation. Results In the control group, the blood supply of optic disc mainly came from the short posterior ciliary artery, pial artery, and retinal ciliary artery; the choroidal capillary vessels around the optic disc didnprime;t take part in the blood supply in the anterior area; retinal central vascular system and complete arterial circle around the optic nerves were not seen. In the operative group, a V-shaped defect of the optic disc, retinal blood vessels and choroidal capillary vessels was found at the surgical incision; no injury of retinal blood vessels and choroidal large vascular layer was seen, and neovascularization at the incision were not found. Conclusions RON may cause the vascular defect of the optic disc and the peripheral local tissues. The depth of the incision doesnprime;t reach the Zinn-Hallers circle. (Chin J Ocul Fundus Dis, 2007, 23: 170-172)
目的 研究薏苡仁水提液对受辐射小鼠外周血白细胞、骨髓有核细胞数量及微核率变化的影响，并检测白细胞介素（IL）-1、IL-2、超氧化物歧化酶（SOD）基因的变化以探讨其抗辐射损伤的作用机制。 方法 用薏苡仁水提液在受辐射前后对小鼠进行灌胃，对辐射后小鼠外周血白细胞、骨髓有核细胞计数，计算微核率，逆转录-聚合酶链反应（RT-PCR）检测IL-1、IL-2、SOD基因的变化，对实验结果进行统计学分析。 结果 随薏苡仁水提液剂量的加大，受照射小鼠骨髓有核细胞数不断增多，且微核数呈降低趋势；高剂量组与空白对照组相比，照射后第7天小鼠外周血白细胞数差异无统计学意义（P＞0.05），且3个剂量组外周血白细胞数均高于辐射对照组，差异有统计学意义（P＜0.01）；薏苡仁水提液高、中剂量组IL-1、IL-2、SOD基因的相对表达量均高于空白对照组和辐射对照组（P＜0.01）。 结论 薏苡仁水提液可能具有促使骨髓有核细胞快速释放、加快外周血白细胞数量恢复进度的作用，且具有降低受辐射小鼠骨髓有核细胞和外周血淋巴细胞微核率的作用；再者，薏苡仁水提液可上调受辐射小鼠机体SOD、IL-1、IL-2的表达水平，具有增强自由基清除、抗辐射和免疫保护调节的作用。
ObjectiveTo evaluate the value of 70 kV and sonogram-affirmed iterative reconstruction technique in CT examination for children with congenital heart disease. MethodsThirty children with congenital heart disease who underwent CT scan between January and September 2014 were included in this study. According to the different tube voltage, they were randomly divided into group A (80 kV) and group B (70 kV), with fifteen in each. All the children were scanned on a dual-source-CT (Siemens Definition Flash). Group A used filtered back projection reconstruction. Group B used sonogram-affirmed iterative reconstruction. We measured and calculated the pulmonary artery signal-to-noise ratio at the level of main pulmonary artery window, the signal-to-noise ratio of the ascending aorta, noise ratio contrast between the pulmonary artery and erector spinae and between the ascending aorta and erector spinae. The image quality for congenital heart disease was assessed by two senior radiologists. The measurement of radiation dose included effective dose (ED), volume CT dose index (CTDIvol) and dose length product (DLP). ResultsThere were no significant differences between group A and B in terms of pulmonary artery signal-to-noise ratio (14.54±3.77, 11.23±2.52), the signal-to-noise ratio of the ascending aorta (14.76±3.41, 12.31±3.47), the noise ratio contrast between pulmonary artery and erector spinae (12.04±3.96, 9.18±3.76) and between the ascending aorta and erector spinae (12.47±4.59, 9.77±4.41) (P > 0.05). There was significant difference between group A and group B in CTDIvol[(0.53±0.09), (0.38±0.03) mGy], DLP[(12.93±1.79), (6.67±0.72) mGy·cm], and ED[(0.34±0.05), (0.17±0.02) mSv] (P < 0.05). ConclusionThe application of 70 kV and sonogram-affirmed iterative reconstruction technique in CT examination for children with congenital heart disease can significantly reduce the radiation dose without any influence on image quality.
ObjectiveTo estimate the radiation dose (RD) to the general public and nuclear medicine technicians from patients undergoing 99mTc-methoxy isobutyl isonitrile (MIBI) myocardial perfusion imaging. MethodsFrom January to June 2015, 55 patients including 30 males and 25 females aged between 25 and 87 years[averaging (63.6±15.1)years] ready to undergo myocardial perfusion scintigraphy with 99mTc-MIBI were prospectively recruited in this study. Approximately at hour 1.5 after injection of 99mTc-MIBI, whole-body dose-equivalent rate was measured with a radiation-survey meter at 0.3 meter and 1.0 meter from the patients. On the basis of human 99mTc-MIBI metabolic rate proposed by the International Commission of Radiological Protection and human social contact model proposed by the National Council on Radiation Protection and Measurements, the RDs to the general public from patients who had completed 99mTc-MIBI myocardial perfusion imaging and left nuclear medicine department were calculated. On the assumption that a nuclear medicine technician typically spent 5 minutes at a distance of 0.3 meter for positioning the patient, the technician's RD was also estimated. ResultsThe RD to a family member sleeping with the patient at night was predicted to be 42.88-160.55 μSv, to a family member contacting the patient at daytime 7.50-29.38 μSv, to a colleague 9.89-38.78 μSv and to a nearby passenger 124.48-466.06 μSv. The RD to a technician per 99mTc-MIBI myocardial perfusion imaging procedure was predicted to be 1.72-6.44 μSv. ConclusionThe predicted RDs to the general public and technicians from exposure of patients undergoing 99mTc-MIBI myocardial perfusion imaging are significantly lower than the regulatory dose limits.
Objective To investigate the effects of ectomesenchymalstem cells on hematopoiesis after total body irradiation in rats. Methods The primary ectomesenchymal stem cells were isolated from E11.5 SD fetal mandibular processes by 25g/L trypsin and cultured with DMEM/F12. The morphology and growthrate were observed by inverted microscope. Eighty SD male rats randomly dividedinto ectomesenchymal stem cells group (n=20), fibroblast group(n=20), saline group(n=20) and control group(n=20), the first three groups were irradiated with 60Co γ rays at 6.0 Gy. The number of their bone marrow nucleated cells was counted after 4 weeks; the forming ability of colony-forming unit-granulocyte macrophage(CFU-GM) and histopathology of bone marrow were also observed. Results The cultured cells displayed monolayer growth and fibroblast-like with 2-4 processes. The ectomesenchymal stem cells could increase the number of bone marrow nucleated cells and peripheral blood white cell count, and improve the forming ability of CFU-GM. After 4 weeks of transplantation, the number of the peripheral blood white cells in group A was more than that in groups B and C(Plt;0.05), the contents of Hb in groups A and D was significantly higher than those in groups B and C(Plt;0.0). After 4 weeks, the bone morrow nucleated cells in group A were significant more than those in groups B and C(Plt;001); CFU-GM in groups A and D was higher than that in groups B and C(Plt;0.01). Conclusion Ectomesenchymal stem cells have characteristics of stem cells. It may improve hematopoiesis recovery of irradiated rats.
ObjectiveTo assess the image quality and radiation dose of gemstone CT coronary angiography (CCTA) with low tube voltage and low concentration contrast medium. MethodsSixty-nine patients who underwent CCTA from January to March 2014 were randomly divided into group A and B. CCTA was performed in thirty-four patients in group A with tube voltage of 100 kV and concentration of contrast medium of 300 mgI/mL. And thirty-five patients in group B underwent CCTA with 120 kV and 370 mgI/mL. According to upgrading American Heart Association standard all segments and all vessels were evaluated. We measured the CT value of ascending aortic root, left main coronary artery, and the initial segment of left anterior descending branch, left circumflex, right coronary artery, and also adjacent tissues. Besides, we recorded CT dose volume index (CTDIvol) and the dose length product (DLP) and calculated effective radiation dose. ResultsThe image quality scores were not significantly different between two groups (P>0.05). The density in the contrast enhanced vessel lumens in group A were signifcantly higher than that in group B (P<0.05). There was no significant difference in signal to noise ratio and carrier to noise ratio between the two groups (P>0.05). Noise in group A was higher than that in group B (P<0.05). The CTDIvol and effective radiation dose in group A were significantly lower than those in group B (P<0.05). ConclusionThe combination of 100 kV with low concentration contrast medium (300 mgI/mL) still maintains the image quality, as well as significantly lowers the radiation dose and the dose of iodine.
ObjectiveTo discuss the value of dual-source CT Flash scanning in reducing the dose of radiation in 3D cardiac imaging. MethodWe collected 60 patients from March to August 2014 who should undergo cardiac 3D CT scanning before radiofrequency ablation. They were randomly divided into group A and B with 30 in each. Patients in group A underwent flash technology scanning, while those in group B accepted conventional retrospective electrocardiography-gated scanning. CARE Dose techniques were used to collect data. Scanning parameters were the same for both groups:collimation was 128×0.6 mm, reconstruction thickness was 0.75 mm, reconstruction interval was 0.7 mm, and field of view was 180-200 mm. After image acquisition, we measured the CT values and noise of left atrium and various branches of the pulmonary veins (upper left, lower left, upper right, and lower right). Statistical software was used for the two groups of images to analyze the carrier noise ratio (CNR), signal noise ratio (SNR), blinded scores, computed tomography dose index (CTDIvol), and dose-length product (DLP) of the left atrium and pulmonary vein. ResultsCNR and SNR of the left atrium and various pulmonary veins between the two groups had no significant differences (P>0.05) . Blinded scores between the two groups were not significantly different (P>0.05) . CTDIvol in group A and group B was respectively (2.92±0.38) and (20.15±12.09) mGy, with a significant difference (t=?7.803, P<0.001) . DLP of group A was (59.30±6.67) mGy·cm, significantly lower than that in group B [(334.43±216.71) mGy·cm] (t=?6.591, P<0.001) . Flash-efficient radiation dose was (0.83±0.94) mSv in group A, far below that in group B [(4.53±3.03) msv], and the difference was statistically significant (t=?6.684, P<0.001) . ConclusionsDual-source CT Flash technology applied in 3D cardiac scanning can reduce radiation dose as well as meet the needs of image diagnosis.