Tritium permeation resistance of Al-Al₂O₃ coatings prepared by thermal spraying / 中国辐射卫生

@#<b>Objective</b> To make the preparation method for coatings more convenient in the field where the requirements for tritium permeation resistance are not high, this paper proposes a method for preparing Al-Al₂O₃ tritium permeation barriers by thermal spraying technology and conducts a performance analysis. <b>Methods</b> The tritium permeation resistance and adhesion of Al-Al₂O₃ coatings prepared by thermal spraying were verified by experiments. <b>Results</b> The tritium permeability was reduced by one order of magnitude after a 0.2-mm Al-Al₂O₃ coating was sprayed on the stainless steel surface, and the tritium permeation resistance had no significant improvement with the increase in coating thickness; the adhesion of the coating was determined in the range of 5-10 N by scratch tests. <b>Conclusion</b> In this paper, a simple preparation method for tritium permeation barrier is proposed, and the tritium permeation resistance performance of Al-Al₂O₃ coatings prepared by thermal spraying technology is determined, which provides a reference for the selection of tritium permeation barrier in the field of tritium-containing solid waste storage.

Establishment of annulus fibrosus partial defect model in sheep / 天津医药

Objective To establish an animal model of annulus fibrosus (AF) partial defect for the repairing of interver?tebral disc (IVD) defect. Methods Image J 1.46r software was used to measure the T12/L1-L6/S1 intervertebral height in ovine lumbar spine X-ray films. AF thickness was measured by axial split disc. A 11 blade was used to make a trapezoid de?fect of upper bottom 3 mm, lower bottom 5 mm, height 5 mm and thickness 3 mm, whose lower bottom toward the nucleus pulposus (NP) in the left front of ovine lumbar IVD in vitro. The minimally invasive lateral approach was used to make the same type of trapezoid defect in the left front of the ovine lumbar IVD in vivo. The trapezoidal defect length of the axial divid?ing disc was measured, AF and a small amount of NP from trapezoidal defect in IVD were weighed, and the production of trapezoidal defect in IVD was evaluated. Results The lumbar intervertebral space height of ovine was (4.45 ± 0.28) mm. There were significant differences in the thickness of AF (4.08±0.50) mm , thickness (3 mm) and height (5 mm) of trapezoidal defect (P0. 05). The weights of the AF and NP taken out from ovine lumbar IVD in vitro and in vivo were (0.162 ± 0.011) g and (0.166 ± 0.014) g, and there was no significant difference between them (P > 0.05). Conclusion Through the operation of minimally invasive lateral approach, the method of making a trapezoidal defect in the experiments can establish animal model of AF partial defect, which meets the requirements for the repairing of IVD defect, and is simple, safe and reliable.

Manufacture and evaluation of integrated biphasic silk fibroin scaffold made by annulus fibrosus-nucleus pulposus tissue engineering / 天津医药

Objective To assess the prospect of integrated biphasic silk fibroin scaffold made by annulus fibrosus-nu?cleus pulposus tissue engineering in application as integrated intervertebral disc(IVD). Methods An integrated annulus fi brosus-nucleus pulposus(AF-NP)biphasic scaffold was made by silk fi broin using two different uncomplicated methods which were paraffin spheres-leaching method(outer AF phase)and phase separation method(inner NP phase). The scaf?fold was investigated by general observation, stereomicroscope and scanning electron microscopy(SEM). Its pore size, poros?ity, and compressive elastic modulus were determined. AF and NP cells were isolated from rabbit IVD and seeded into the corresponding phase of the scaffold respectively. The cell-scaffold complex was cultured for 48 hours. The biocompatibility of the scaffold was evaluated by SEM, live/dead staining while CCK-8 assay was used to assess cell proliferation. Results Stereomicroscope and SEM showed that AF phase and NP phase integrated perfectly without cross-linking. Both phases pos?sessed highly interconnected porous structure [pore size of AF and NP phase were(220.0±23.1)μm and(90.0±17.8)μm, re?spectively] and highly porosity(AF and NP phase were respectively 91%and 93%). In addition, this silk biphasic scaffold had impressive mechanical properties(150.7 ± 6.8)kPa. SEM revealed that disc cells attached to regions of pore walls, dis?tributed uniformly and secreted extracellular matrix. Live/Dead staining and cell count kit-8(CCK-8)analysis showed that the silk composite scaffold was non-cytotoxic to disc cells. Conclusion This silk biphasic AF-NP scaffold has satisfied pore size, porosity, biomechanical properties and biocompatibility, so it is ideal candidate for IVD tissue engineering.

Clinical value of ultrasonographic assessment for the risk of lower limb deep vein thrombosis defluvium / 中华超声影像学杂志

Objective To evaluate the possibility of deep vein thrombosis defluvium of lower limb using ultrasonography to provide important reference for the implantation and retrieve of retrievable inferior vena cave (IVC ) filters.Methods Sixty-four patients who were diagnosed as lower limb deep vein thrombosis using ultrasonography were enrolled.Fourteen patients with critical values were allocated to high risk group,50 patients without critical value to low risk group.All the patients underwent inferior vena cava filter operation.Of all these patients,ultrosonography were performed once again before IVC filters were retrieved.Seventeen patients with broken thrombosis were allocated to unstable group,47 patients with stable thrombosis to stable group.Relationships between conditions of thrombosis and ultrasonography results were analysed.The conditions of thrombosis were recorded.The rates of thrombosis defluvium were compared.Results In high risk group,10 patients (71 .43%)had thrombosis.In low risk group,8 patients (16%)had thrombosis.There were significant differences in the rates of thrombosis defluvium beteen the high risk group and low risk group(P <0.05).In unstable group,12 patients (70.59%)had thrombosis.In stable group,6 patients (12.77%) had thrombosis,there were significant differences in the rates of thrombosis defluvium between the unstable group and stable group (P < 0.05 ).Conclusions Ultrasonography can be used to evaluate the possibility of lower extremity deep vein thrombosis defluvium which will guide the pratice of the retrievable inferior vena cava filter.

Exploration of Appropriate Cross-Matching Methods for Positive Patients of the Direct Antiglobulin Test / 现代检验医学杂志

Objective To investigate the appropriate cross-matching methods for the direct antiglobulin test (DAT)positive patients.Methods The DAT was used to screen the irregular antibodies on the surface of erythrocytes.The microcolumn gel test was used for blood identification.The antiglobulin test and manual polybrene test were used for cross-matching.Re-sults A total of five DAT positive cases were collected in study.The blood groups of each case were detected,including A-DCcEe,O-DCCee,O-DCcee,A-DCCee and A-DCcee.The donor samples with corresponding blood-antigen negative were cho-sen for cross-matching,and the agglutination intensity of each cross-matching tube was weaker than the control.The transfu-sion of washed red blood cells was suggested.Finally,each transfusion was safe and efficient.Conclusion The infusion of the washed red blood cells with corresponding blood-antigen negative could efficiently ensure the safety of blood transfusion.

Preliminary Construction of Tissue Engineering Nucleus Pulposus Combining Silk Fibroin Porous Scaffold with Rabbit Nucleus Pulposus Cells / 天津医药

Objective To investigate the feasibility of construction of tissue engineering nucleus pulposus by com?bining the novel silk fibroin porous scaffold with PKH26 labeled rabbit nucleus pulposus cells. Methods Rabbit nucleus pulposus cells were isolated and cultured, then the passage 1 nucleus pulposus cells were stained with safranin O and typeⅡcollagen immunohistochemical staining. The isolated rabbit nucleus pulposus cells were labeled with PKH26. MTT assay was used for examining the proliferation of the nucleus pulposus cells before and after labeling. Labeled cells were inoculat?ed in the scaffold, cultured for 4 days and then the cell-scaffold complexes were implanted subcutaneously into nude mice. After 12 weeks of in vivo culture, the cell-scaffold complexes were detected by in vivo imaging technology, H&E staining, toluidine blue staining, safranin O staining and collagen typeⅡimmunohistochemical staining. Results Safranin O stain?ing and typeⅡcollagen immunohistochemical staining of the passage 1 nucleus pulposus cells were positive. The fluores?cence intensity of labeled cell was distributed, and the difference of OD value of nucleus pulposus cells was not statistically significant before and after labeling (P>0.05). The in vivo imaging technique showed a strong fluorescencea in porous scaf?fold. H&E staining of cell-scaffold complexes showed that the scaffolds were filled with a large number of nucleus pulposus cells and large amount of extracellular matrix. Toluidine blue staining, safranin O staining and typeⅡcollagen immunohisto?chemical staining were positive, and large amount of extracellular matrix was secreted around the cells. Conclusion The new silk fibroin porous scaffold with rabbit nucleus pulposus cells in vivo culture formed nucleus pulposus like tissue, which can be used for construction of tissue engineering nucleus.