10.3969/j.issn.2095-4344.2013.26.024

OBJECTIVE: To establish HPLC method for the determination of the contents of atenolol, hydrochlorothiazide and nifedipine in xueyaan sustained release tablets. METHODS: The determination was performed on ZORBAX SB C18 column with column temperature at 35℃ . The mobile phase consisted of 0. 01mol? L- 1 sodium dihydrogen phosphate solution- methanol- acetonitrile ( 6∶ 3∶ 1) . The UV detection wavelength was set at 272nm and the sample size was 20? L. RESULTS: The liner ranges of atenolol, hydrochlorothiazide and nifedipine were 10～ 250? g? mL- 1 ( r=0. 999 4) , 6～ 150? g? mL- 1( r=0. 999 6) , and 5～ 125? g? mL- 1( r=0. 999 2) respectively. The average recovery rates of the three constituents were ( 98. 51? 0. 98) % ～ ( 99. 12? 0. 98) % , ( 98. 87? 1. 10) % ～ ( 99. 69? 1. 43) % , and( 98. 80? 1. 27) % ～ ( 99. 38? 1. 13) % , respectively, with RSD at 1. 00% , 1. 17% , and 1. 25% , respectively. CONCLUSION: The established method is simple, sensitive and reproducible, and suitable for the quality control of xueyaan sustained release tablets.

1. The upper tributaries of great saphenous veins were divided into 15 types. TypeⅥ, in which the superficial iliac circumflex vein, the superficial epigastric vein and thelateral superficial femoral vein together constituted a pattern of the common trunk, wasthe most frequent one, comprising 53 sides, amounting to 25.61 per cent. 2. The average length of 156 sides of great saphenous veins was 76 cm, the longestwas 85 cm. and the shortest 65 cm. 3. With reference to the bone landmarks of lower limbs, the saphenous vein wason average 0.8 cm. from the infero-anterior margin of malleolus medialis of tibia, 5.5 cm.from the anterior middle one third of the crista of the tibia, and 1.95 cm. from the pos-terior aspect of the medial epicondylus of the femur. 4. The distance between the lower margin of the saphenous femoral junction andthe lower margin of the inguinal ligament was on the average 4.3 cm. 5. The average number of valves of the great saphenous veins was 8. The highestincidence ranged from 5--10 valves, comprising 83.58 per cent of all the cases. 6. The authors suggested that the commonly designated terms medial and lateralacessory saphenous veins should be replaced by medial and lateral superficial femoral veinsrespectively, according to their receptive scopes and the rule of anatomical nomenclature.

BACKGROUND:In three-dimensional CT reconstruction model, fracture virtual reduction and internal fixation cannot be achieved, and reasonable operation scheme cannot be formulated. It cannot fuly meet the needs of clinical orthopedics physicians. OBJECTIVE:To explore the methods to perform three-dimensional reconstruction, reduction on proximal tibial fracture and to design digital plate using software. METHODS:Nine specimens of knee joint were built to be A1-3, B1-3 and C1-3 types of proximal tibial fracture according to the AO standard. Al specimens were treated with CT scan. Three-dimensional reconstruction and reduction on nine types of bone fracture models were performed in Mimics. The digital plates and screws were designed in Solidworks. Virtual internal fixation on the reduced three-dimensional models was performed. RESULTS AND CONCLUSION:Al bone fracture models received three-dimensional reconstruction and reduction, and the design for internal fixational plates and screws as wel as virtual internal fixation were accomplished. A3, B3 and C3 types were presented. These results suggest that the digital plates for proximal tibial fracture could be designed in Mimics and Solidworks with a personal computer. Our experience could be used in the real operation.

BACKGROUND:Odontoid fracture is very common in cervical spine injuries, the special position of odontoid process, which is adjacent to important anatomic structure, makes screw placement difficult, and a slight discrepancy in position and orientation of the inserted screw leads to a decrease in intensity of internal fixation, even invalid internal fixation. Therefore, it is very necessary to develop an individualized treatment protocol by which screws can be precisely and safely placed and which is worthy of clinical popularization. OBJECTIVE:To study the navigation of Mimics software and three dimensional (3D)-printed module in anterior odontoid cannulated screw fixation and to investigate its feasibility and accuracy. METHODS:Sixteen human cadaveric cervical spines were scanned by a continuous thin-slice CT scanner. Original DICOM CT images were three-dimensional y reconstructed using Mimics software. The screw channel and support column were designed for C2 vertebra odontoid cannulated screw fixation for odontoid fracture. Segmentation of bone surface was performed. Navigation modules with screw channel were built using 3D printing technique. Navigation modules were used to aid screw placement. Screw fitting and placement were evaluated using X-ray and CT scan. RESULTS AND CONCLUSION:Total y 16 navigation modules were built and 22 screws were implanted. During and after screw placement, the cortical bone along screw channel and surrounding the vertebral body was not cracked. Postoperative X-ray and CT scans showed that some factors regarding screw placement such as entry point, orientation and depth of placement were consistent with those ideal factors simulated by Mimics software. The navigation modules were closely attached to the corresponding bony structure in front of the vertebral body, with a satisfactory gomphosis. Screw fitting and stability were good during application. These results verify that with the aid of navigation module, anterior odontoid cannulated screw fixation is reliable for treatment of odontoid fracture, which provides insights into the popularization of 3D printing-based digital navigation technique in orthopedic implantation.

BACKGROUND:On CT reconstruction of three-dimensional (3D) model, fracture virtual reduction and internal fixation cannot be achieved, and reasonable operation scheme cannot be formulated. Digital design can fuly meet the needs of clinical orthopedics physicians. Standard parts database can provide the possibility to choose the ideal internal fixation. 3D printing makes the reasonable operation scheme accurate in clinical implementation. OBJECTIVE:To discuss the feasibility, accuracy and minimal invasion of internal fixation in treatment of the distal femoral fracture with digital design of standard parts database by 3D printing. METHODS: (1) Nine adult lower extremity specimens were selected to take continuously thin-layer CT scanning. After Dicom images were imported into the mimics software, the model was established. According to the AO classification, they were classified into A1-3, B1-3 and C1-3 types of distal femoral fracture by virtual design. Internal fixation with plate and screw formed standard parts database virtualy. It was printed out the pilot hole of the navigation module design by three-dimensional printing forming technique. Plate and screw were inserted assisted by the module. X-ray and CT scan were taken postoperatively to access the position. (2) 30 patients with distal femoral fracture were subjected to above fixation. The operation time, intraoperative blood loss and postoperative drainage were recorded. Imaging and curative effects were evaluated during folow-up. RESULTS AND CONCLUSION: (1) Nine samples underwent X-ray and CT scan. 3D reconstruction results revealed plate position, screw entry point, nail direction, length and diameter were consistent with presetting data in Mimics software. The navigation models were designed to fit the lateral bony structure of distal femur. There were good fitting degree, good card position and good stability when the navigation was applied. It could guide plant and screw implantation. (2) In 30 cases, the operation time was (104.63±26.12) minutes, intraoperative blood loss was (121.74±11.49) mL, and postoperative drainage volume was (30.29±6.38) mL. Al patients were folowed up. According to Schagzker criterion, the efficiency of 22 cases was excelent, 6 cases good and 2 cases average, and the excelent and good rate was 93%. The parameters of length, diameter, orientation and angle were consistent with that preoperatively. (3) Internal fixation formed by standard parts database assisted by 3D printing navigation model has advantages of high accuracy, short process, lessened blood loss, high safety, less complications, and precise fixation. Digital design of standard parts database via3D printing navigation module is expected to achieve implant navigation and application.

BACKGROUND:Preliminary experiments have performed three-dimensional (3D) reconstruction of proximal tibial fractures, digital steel plate design, the establishmentof the proximal tibia plate standard parts library and the operation simulation of 3D printing. OBJECTIVE:To explore feasibility and accuracy of standard parts library plates and screws in the proximal tibial fracture internal fixation navigation in digital design combined with 3D printing model on the basis of preliminary studies. METHODS:Dicom format images of continuous thin layer CT scanning were colected in 20 cases of proximal tibial fractures, and uploaded in Mimics software for 3D reconstruction and fracture reduction. Plate and screw selected from standard part library wereusedfor virtual fixation. Navigation module with screw channel was designed. 3D printing skeleton, bone plate, and navigation module were used for skeleton model and internal fixation. Screw and plate were placed by navigation. Navigation module card, nail and board position were observed. Postoperative appearance and CT scanning were utilized to assess outcomes. RESULTS AND CONCLUSION:After CT scanning and reconstructionin 20 skeleton models, in combination with appearance, the position of plate, screw insertion point, the direction, length and diameter of the screw were consistent with that in Mimics software. The navigation module and the corresponding proximal end of the tibia were closely bonded with good fitting degree. In the application, card slots and stability were good, and could perfectly guide plate and screw placement. These reuslts suggest that with the aid of navigation module, standard parts library plate internal fixation for proximal tibia fracture has high accuracy. On the basis of digital design and 3D printing, digital internal fixation technology of standard parts library plate is expected to achieve good implant navigation in the department of orthopedics.

By integrating bone-remodeling theory with finite element (FEM) models, the behavior of femoral remodeling after implantation of artificial femoral head was simulated and the stress shield effect of artificial femoral head on the femur was analyzed quantitatively. Bone was calculated with finite element code of the FEM model. The normal loading condition of femur was used as Model One, and the stress condition that bone was fixed by the bone-cement of the artificial head with collar was used as Model Two. It has been shown that bone was stress-shielded by the artificial femoral head and femur resorbed. Bone resorption near the proximal artificial stem was very severe. Its cross-section resorbed the greatest. The ratio of cross-sectional resorption was psi = 31.3% and the ratio of loss of the anti-bend cross-sectional modulus was zeta = 54.58%.
Arthroplasty, Replacement, Hip ; Bone Remodeling ; Bone Resorption ; Computer Simulation ; Femur Head ; physiology ; Finite Element Analysis ; Hip Prosthesis ; Humans ; Postoperative Period ; Software ; Stress, Mechanical

OBJECTIVE To analyze trimethylation of genome-wide histone H3 lysine 4(H3K4met3) induced by silicon dioxide(SiO2)through chromatin immunoprecipitation linked to microarrays(ChIP-chip)in lung fibroblast(LF)of rats. METHODS A primary co-culture model of rat alveolar macrophages (AM)and LF in vitro. AM were exposed to 100 mg · L-1 free SiO2 for 24 h,before LF were collected and the phenotype of LF was determined after transdifferentiation by immunohistochemistry. ChIP-chip was used to profile the variations of trimethylation in H3K4 of lung fibroblasts in CpG island regions. ChIP-qPCR was used to validate the microarray results. The mRNA expression of nfib and kpna3 was analyzed by qRT-PCR. RESULTS Totally 1815 (518 increased and 1297 decreased) genes of H3K4met3 displayed significant differences in SiO2 100 mg·L-1 group compared with control group(Cy3/Cy5 value>2.0 or <0.5,NimbleScan V2.5 software). The results of ChIP-qPCR were quite consistent with those of microarray. CONCLUSION There are significant differences in methylation of genome-wide H3K4 between SiO2 100 mg·L-1 group and control group. These novel candidate genes may become potential biomarkers or new interfered targets.

Objective: To analyze Internet behaviors of children and adolescents and their influencing factors, and to provide scientific basis for health education guidance and prevention measures. Methods: A stratified cluster sampling method was used. From January to June 2019, 30 955 primary school students in 16 provinces (municipalities), from eastern, central, and western economic zones of China were selected to conduct a questionnaire survey, regarding general demographics, diet and exercise, tobacco, alcohol and sleep, Internet and electronics usage, etc. Results: Among them, 43.1% of students had never been online with girls (44.7%) higher than boys (41.8%)(χ2=21.04, P<0.01); 1.3% of students reported online time for more than 4 hours a day, boys were significantly higher than girls(χ2=15.87, P<0.01); Internet addiction was detected in 2.4% of elementary school students, with boys (3.0%) higher than girls(1.7%)(χ2=331.77, P<0.01), and the trend increases with grade. With sixth grade (3.3%) were significantly higher than children from the first grade (0.8%) and other grades(χ2=163.96, P<0.01). Children’s tendency to Internet addiction was 11.9%, of which boys were 13.0% and girls were 10.6%, boys were significantly higher than girls(χ2=117.66, P<0.01). Pearson correlation analysis revealed that, after controlling gender age, boarding school, family relationship, single parents and regrouped families, smoking, drinking sugary drinks, eating fried foods, and left-behind were positively related to Intenet addiction(r=0.06, 0.07, 0.27, 0.44, 0.07, 0.11, 0.09, P<0.01), while medium and high intensity sports, effective physical education, health education in school, AIDS education and parental restrictions on TV and computer games, were negatively associated with internet addiction(r=-0.74, -0.65, -0.04, -0.05, -0.63, P<0.01). Conclusion The internet addiction of Chinese primary school students is common and increases by year. High-intensity, high-density sports, effective physical education, and health education could help prevent Internet addiction among children.