Objective To evaluate the similarities and differences between four-dimensional radiotherapy (4D-CT ) and active breathing control techniques(ABC) in respiratory management in lung radiotherapy ,and investigate the indications and feasibility of different breathing control techniques for different patients .Methods Twenty-one patients treated with lung radiotherapy received respiratory management .4D-CT technology was used in 11 patients ,while ABC technology was adopted in the rest 10 .The ratios of planning target volume(PGTV) to gross tumor volume(GTV)[(PGTV/GTV)] were calculated .The differences between these two respiratory management technologies were compared in terms of the PGTV ,positioning time ,planning time and treatment time to investigate the indications .Results 4D-CT technology had higher PGTV/GTV ratio ,and shorter positioning time and irradiation time than ABC technology(P<0 .05) ,but there was no significant difference in the planning time(P>0 .05) .In patients with ABC and 4D-CT technology ,objective response rates were 50 .0% ,45 .5% ,respectively ,and the radiation pneumonitis rates were 30 .0% ,27 .3% ,respectively .There was no significant difference in both groups (P>0 .05) .Conclusion In lung tumor radiothera-py ,ABC can reduce irradiation volume ,suitable for patients with good performance status .4D-CT is time-saving and well tolerated , suitable for patients with smaller tumors .

BACKGROUND:Diameter and length of mini-implant have effects on its stability, which has been reported mostly in I and II osteoid, but less in IV osteoid. OBJECTIVE:To optimize the design of mini-implant diameter and length in IV osteoid by a three-dimensional finite element analysis. METHODS:Implant-mandible solid model was established. A 2 N orthodontic force that was perpendicular to the long axis of the implant and at a 30° angle with the distal central axis was applied onto the top of the implant. The implant was designed for different diameters (1.2-2.0 mm) and lengths (6-10 mm). Peak stress and peak displacement of the mandible were mechanicaly assessed, and stress sensitivity variables were analyzed. RESULTS AND CONCLUSION:The stress and displacement of the implant were mainly concentrated in the neck of the implant. The stress of implant-bone interface mainly focused on the contact area of the implant-cortical bone interface, and the stress of the cancelous bone was relatively smal, but the stress of the cortical bone was weakened faster. When the implant length was constant, the implant diameter had a great effect on stress changes, and the stress of bone tissue was reduced with the increase of implant diameter. When the implant diameter was constant, the implant length had no significant effect on the stress of bone tissue. To sum up, the stress of bone tissue and displacement were sensitive to the change of implant diameter rather than the change of implant length. These findings indicate that implant diameter has a greater effect on stress distribution of bone tissue than the implant length, and the implants with > 1.5 mm in diameter are suitable for IV osteoid.

Objective To analyze the efficacy,dose and complications of total body irradiation(TBI) for patients to receive hematopoietic stem cell transplantation(HSCT) in the treatment of leukemia and malignant lymphoma.Methods From May 2002 to February 2007,78 cases with leukemia or malignant lymphoma received the TBI before HSCT in our department.All the patients were irradiated with linear accelerator in 2 consecutive days at a total dose of 7 to 11 Gy,dose rate of 4.5 to 5.0 cGy/min,once per day.Among them,55 cases received traditional high-dose chemotherapy before radiotherapy,and the other 23 cases got TBI first followed by high-dose chemotherapy.Results All the cases used TBI prior to transplantation was successful,and no serious complication such as radiation pneumonitis was observed.Conclusion Our TBI regime is a safe and effective pretreatment for HSCT.TBI used before the large doses of the chemotherapy is recommended because it is proved to be effective,without affecting the survival rate,and of lesser TBI reaction and of lesser preparation work for irradiation to radiotherapist.More attention should be paid when the linear accelerator is employed for TBI.

Objective To study the change and relationship among thrombopoietin (TPO), platelet parameter and megakaryocyte in immune vasculitis of weanling rabbits. The role of platelet parameter, megakaryocyte, thrombopoietin (TPO) in kawasaki disease (KD) was accessed. Methods An experimental model of weanling rabbits for KD was reproduced by bovine serum. The blood platelet counts (PLT), mean platelet volume (MPV), platelet distribution width (PDW), platelet hematocrit (PCT), megakaryocyte and TPO were determined ev-ery four days. Pathological analysis of coronary artery, liver, spleen, kidney, brain was also done. Results PLT, PCT, PDW and the per-centage of total number of megakaryocyte and middle board megakaryocyte in the experimental group had obviously changes at the 12th, 16th, 20th, 24th, 28th day (P <0.05). MPV in the experimental group had obviously changes in the 12th, 24th, 28th day(P <0.05). TPO in the experimental group was higher than that in control group (P < 0.05). TPO in both groups was positively correlated with PLT, PCT, the percentage of total number of megakaryocyte and middle board megakaryocyte (P < 0.05). In experimental group, small arteries showed obvious inflammatory injury at the 17th day, medium-sized arteries showed obvious inflammatory injury at the 28th day, but the aortas showed mild changes. Conclusion Platelet, megakaryocyte and TPO took part in the pathogenesis of KD, and they had interaction and co-ordination in the course of regulation, which suggested that they could be used to monitor the changes in the KD and guide the treatment.

10.3969/j.issn.1000-8179.2013.12.003

BACKGROUND: Previous studies have found that nerve growth factors play an important role in the process of wound healing, but there is less research for the low-affinity nerve growth factor receptor p75 and sortilin in fibroblasts, and no reports on whether there are differences in expression of p75 and sortilin in the scar fibroblasts and normal skin fibroblasts. OBJECTIVE: To study the expression of low-affility nerve growth factor receptor p75 and sortilin in the normal human skin fibroblasts and the human keloid fibroblasts. METHODS: The keloid fibroblasts and normal hunman skin fibroblasts were cultured in vitro, and the immortalized epithelial cells HaCaT were used as the positive control. The real-time PCR was used to detect the mRNA expression of the p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts, and western blot and immunocytochemical staining were used to detect the protein expression of p75 and sortilin. RESULTS AND CONCLUSION: The real-time PCR and western blot results showed that in the protein and mRNA levels, p75 and sortilin showed positive expression in the keloid fibroblasts and normal human skin fibroblasts, and there was no significant difference in the expression of p75 between keloid fibroblasts and normal human skin fibroblasts, and the expressions of p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts were significantly lower than those in HaCaT. There was no significant difference of p75 expression between keloid fibroblasts and normal human skin fibroblasts, and the expression of sortilin in the keloid fibroblasts was significantly lower than that in the normal human skin fibroblasts (P < 0.05). Immunocytochemical staining result showed that the expression of p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts were distributed in the membrane and cytoplasm. Precursor nerve growth factor combined with high-affinity p75 receptor could promote the apoptosis of the cells with the help of sortilin, and the expression of sortilin in the keloid fibroblasts was significantly lower than that in the normal human skin fibroblasts, which may associated with the high proliferation of the keloid fibroblasts. The results provide a new target for the prevention and treatment of pathological scars.

Teachers introduced the means of the scientific thinking and scientific research prac-tice in the curriculum of proteomics in order to train the postgraduates to joint the theory and the practical research work in the curriculum course. For example, to cultivate students to truly understand the 2-DE protein separation technique, teachers used the various proteomic profile obtained from our research to points out its problems and limitations based on the classical 2-DE, then compared the improved 2-DE protein separation chromatography with the classical 2-DE graphic and analyzed what is the problem and how to solve them in the practical work. To improve the ability of scientific thinking for postgraduates , teachers took the tumor as the teaching cases and asked the postgraduates to search the references of can-cer associated with their professional , to put forward the scientific problems based on carefully reading these references, to design their research project and to seek the answer to their issue. These new teaching methods were found to be beneficial in training scientific talents of medical postgraduates.

Objective To investigate the level and proportional relationship of free fluorine and soluble fluoride in different brands of toothpaste,and analyze possible risk factors.Methods A total of 54 samples of commercially available toothpastes of domestic,joint venture and imported in Guiyang City were collected,and the levels of free fluoride and soluble fluorine were determined,respectively,using fluorideion selective electrode.method (GB 8372-2008).Results The number of the toothpaste was 32,12,10,respectively,in domestic,joint venture and imported.The levels of free fluorine ranged from 0.98 to 1 603.50 mg/kg,3.22 to 617.50 mg/kg and 306.80 to 1 590.80 mg/kg,respectively,in toothpastes of domestic,joint venture and imported; the number of exceeding the standard free fluorine was 3,0 and 1,respectively,in toothpastes of domestic,joint venture and imported; the rate of exceeding the standard free fluorine was 9.4％,0.0％ and 10.0％,respectively,in toothpastes of domestic,joint venture and imported.The levels of soluble fluorine ranged from 3.06 to 4 302.50 mg/kg,9.02 to 1 667.30 mg/kg and 9.18 to 4 013.20 mg/kg,respectively,in toothpastes of domestic,joint venture and imported; the number of exceeding the standard soluble fluorine was 9,2 and 3,respectively,in toothpastes of domestic,joint venture and imported; the rate of exceeding the standard soluble fluorine was 34.4％,16.7％ and 30.0％,respectively,in toothpastes of domestic,joint venture and imported.The proportion of free fluorine and soluble fluoride was:domestic 1.0 ∶ 2.7,joint venture 1.0 ∶ 2.7,imported 1.0 ∶ 2.5,respectively.The confidence limit (R/d) was 0.98.Conclusion The fluoride level in different brands of toothpaste has exceeded the standard,the content and proportion of soluble fluoride are obviously higher than those of free fluoride,and there is a risk on tooth damage from fluoride,and factories should strengthen quality control in adding fluoride.

Objective To find a novel operative modality with sphincter preservation in the treatment of middle and low rectal carcinoma. Methods Pull through lower resection was performed on 28 rectal cancer patients. The distance between the anal verge and the lower margin of the tumor was 6～8cm(20 patients) or 8～10cm(8 patients), including 8 patients in Dukes A stage, 16 Dukes B and 4 Dukes C. The resected line from tumor distal margin was 2cm, 3cm, and 4cm, respectively. Results There was no operative death, anastomotic fistula or anastomotic stenosis in these cases. Mean follow up period was 30 months. Local recurrence was found in two cases (7.1%) 18 months after the operation, and 26 cases were cancer free till the end of the follow up. Defecation was satisfactorily controlled 8～12 weeks after the operation. Conclusions Pull through Welch procedure could meet the criterion of the radical resection of rectal carcinoma,and keep the internal and external sphincter muscles intact in the superior lower anterior resection. The normal defecationcan can maintain after the operation due to the preservation of internal and external sphincter muscles.

Objective To study the feasibility of Brainlab plus 6-degree-of-freedom(6D) couch in the radiotherapy of head and neck by using their setup error.Methods Twenty-four patients with head and neck neoplasms in our hospital during AugustOctober 2016 were taken as the examples.After positioning by technician,each Brainlab was carried out,the setup errors in 3 translation directions of left-to-right(X),head-to-foot(Y) and abdomen to-back(Z) and 3 pivoting directions of Rx,Ry and Rz were obtained after registration of positioned CT image.After adjustment,Brainlab re-scanning was conducted for getting corrected errors.Results The online correction by Brainlab plus 6D obviously reduced the setup errors.The setup errors in all directions approached to 0,in which the difference between Ry and Rz directions had no statistical significance(P＞0.05),while the difference among the X,Y,Z and RX directions was statistically significant(P＜0.05).Conclusion The online corrections of Brainlab combined with 6D considerably reduces the errors in translation and rotation directions in radiotherapy of head and neck neoplasms,thus reduces normal tissue received amount and increases the radiotherapeutic accuracy.