Analysis of influencing factors on post-treatment in-stent stenosis of intracranial aneurysm using Pipeline embolization device / 中华放射学杂志

Objective:To evaluate the incidence, clinical significance and influencing factors on in-stent stenosis(ISS) after treatment of intracranial aneurysms by Pipeline embolization device(PED).Methods:A retrospective analysis was conducted on the clinical data of 161 patients with intracranial aneurysms treated with PED at the Department of Interventional Radiology of the First Affiliated Hospital of Zhengzhou University from April 2015 to July 2021. PED was implanted into the parent artery through the femoral artery approach after general anesthesia. The first DSA follow-up duration time and imaging data were collected, and the patients were divided into ISS group and non-ISS group accordingly. The degree of aneurysm occlusion was evaluated by O′Kelly-Marotta(OKM) grading scale. Univariate and multivariate logistic regression analysis were applied to identify the factors related to ISS.Results:A total of 179 PED were employed in 161 patients with 168 aneurysms. Eighty-eight (52.38%) aneurysms were treated by PED only, and 80 (47.62%) aneurysms by PED combined with coiling. After a median follow-up of 6 (5, 7) months, 31(18.45%) aneurysms had ISS within the PED, of which 16(9.52%) cases were with mild stenosis (<50%), 13 (7.74%) were with moderate stenosis (50%-75%), and 2(1.19%) were with severe stenosis (>75%). All patients with ISS showed no relevant clinical symptoms. One (0.60%) patient with ISS underwent balloon angioplasty. Univariate analysis showed that the stent diameter, aneurysm location, triglyceride level, the diameter of distal parent artery, and the diameter of proximal parent artery were associated to ISS. Further multivariate logistic regression analysis showed the stent diameter (OR=0.332, 95%CI 0.191-0.578, P<0.001) and triglyceride level (OR=1.641, 95%CI 1.034-2.605, P=0.036) were independent factors of ISS. Conclusions:ISS is a common benign complication after PED treatment. The current results suggest that small stent diameter and high triglyceride level are independent factors of ISS.

Design and simulation for seeding performance of high-speed inclined corn metering device based on discrete element method (DEM).

Mechanical precision corn seed-metering planter has a compact structure, missed and repeated seeding advantages during high-speed operation. In this regard, the current research study focuses on the development of a corn seed planter that features an inclined seed-metering device. The spatial layout of the seed-metering device is optimized to change the seed-filling mode to meet the needs of high-speed operation. Firstly, the mechanical characteristics and seeds in the metering device chamber were analyzed, and then the seed-filling stress model was established. Secondly, a mechanical model for corn seed particles was developed for virtual simulation tests and numerical analysis using the discrete element method (DEM) and EDEM software. Moreover, a quadratic rotating orthogonal center combination test was implemented by setting the inclination angle of seed-metering device θ(A), machine ground speed v(B), and rotation speed of metering disc n(C) as the influence factors, with the missed seeding rate M and the seed-filling stress S as the evaluation indices. The results indicated that the most significant factors affecting the missed seeding rate, seed-filling stress, S, were the rotation speed of the metering disc (n) > machine ground speed (v) > inclination angle of the metering disc (θ) and inclination angle of the metering device (θ) > rotation speed of the metering disc (n) > machine ground speed (v), respectively. However, the field verification test shows that the optimized corn seed-metering planter achieved mean values of M = 4.33, Q(qualified seeding rate) = 92.83%, and R(repeated seeding rate) = 2.84%, with average relative errors of 1.17% compared to the simulation tests and the accuracy and effectiveness of the DEM simulation model was verified. Therefore, the developed corn seed-metering device meets the industry standards and operation requirements for precise corn sowing, and technical support can be given for future studies of similar precision seeding equipment.

A highly sensitive detection of chloramphenicol based on chemiluminescence immunoassays with the cheap functionalized Fe3 O4 @SiO2 magnetic nanoparticles.

A strategy has been applied to chloramphenicol (CAP) detection with chemiluminescence immunoassays (CLIA) based on cheap functionalized Fe3 O4 @SiO2 magnetic nanoparticles (Fe-MNPs). The strategy that bovine serum albumin (BSA) was immobilized on cheap functionalized Fe-MNPs and that the CAP molecules were then immobilized on BSA, avoided the long process of dialysis for preparation of the BSA-CAP conjugates. The samples were detected for both methods that utilized two different kinds of functionalized Fe-MNPs (amine-functionalized Fe3 O4 @SiO2 and carboxylic acid-functionalized Fe3 O4 @SiO2 ). The sensitivities and limits of detection (LODs) of the two methods were obtained and compared based on inhibition curves. The 50% inhibition concentrations (IC50 ) values of the two methods were about 0.024 ng ml-1 and 0.046 ng ml-1 respectively and LODs were approximately 0.0002 ng ml-1 and 0.001 ng ml-1 respectively. These methods were much more sensitive than that of any traditional enzyme-linked immunosorbent assay (ELISA) previously reported. Therefore, such chemiluminescence methods could be easily adapted for small molecule detection in a variety of foods using Fe-MNPs.

Prokaryotic expression and purification of the cDNA of recombinant human cytokeratin 9 / 西安交通大学学报(医学版)

Objective To clone and fuse the cDNA of human cytokeratin 9 in prokaryotic expression system,and purify and identify the fusion protein.Methods The cDNA fragment of human cytokeratin 9 was amplified from human keratinocyte (HaCaT) total RNA with specific primers.The PCR products were cloned into vector pET-28a,then the fusion protein of his-CK9 was induced by IPTG.The expressed fusion protein of his-CK9 was purified by nickel ion affinity chromatography and identified by SDS-PAGE and Western blot.Results The sequencing proved that the recombinant vector of the cDNA of CK9 was correct.The fusion protein of his-CK9 was induced to be expressed in E.coli.The fusion protein of his-CK9 was highly purified and his-CK9 showed specific binding to the commercialized antibodies of CK9.Conclusion The recombinant vector of pET-28a-CK9 has been successfully constructed,and the fusion protein of his-CK9 has been successfully expressed and purified.