[The Occurrence and Risk Factors of Stroke Complicated by Venous Thromboembolism].

Objective: To investigate the occurrence and the risk factors of stroke complicated by venous thromboembolism. Methods: A total of 2709 stroke patients who received treatment at our hospital between January 2018 and June 2021 were selected. The incidence of stroke complicated by venous thromboembolism was analyzed and the risk factors of stroke complicated by venous thromboembolism were investigated by logistic regression. Results: Among the 2709 stroke patients, 390 had venous thromboembolism, resulting in 14.39% incidence of venous thromboembolism. Among them, 383 patients (14.14%) had deep venous thrombosis (DVT), 4 patients (0.15%) had pulmonary thromboembolism (PTE), and 3 cases (0.11%) had DVT combined with PTE. According to the analysis of unconditional multivariate logistic regression model, age>60 years, concomitant hypertension, concomitant diabetes, bedrest time after admission≥3 days, D-dimer (D-D)≥0.95 mg/mL, triglyceride (TG)≥1.83 mmol/L, Barthel Index (BI) score≤9 points, and Padua score>4 points after admission were independent risk factors for stroke complicated by venous thromboembolism ( P<0.05), while anticoagulation therapy was a protective factor ( P<0.05). Conclusion: Stroke complicated by venous thromboembolism is associated, to some degree, with age, concomitant hypertension, concomitant diabetes, bedrest time, D-D, TG, BI score, Padua score, and whether anticoagulant therapy is administered or not. Interventions in line with relevant risk factors should be strengthened to effectively reduce the risk of stroke complicated by venous thromboembolism.

Facile Synthesis of Fe3O4@Tannic Acid@Au Nanocomposites as a Catalyst for 4-Nitrophenol and Methylene Blue Removal.

A facile, cost-effective, and eco-friendly method was proposed to synthesize Fe3O4@tannic acid@Au nanocomposites (Fe3O4@TA@Au). First, Fe3O4 nanoparticles with diameters of 20 and 200 nm were synthesized by co-precipitation and solvothermal methods, respectively. Gold nanoparticles were deposited on magnetic Fe3O4 through tannic acid-metal-polymer intermediate-layer-mediated reductions. The catalytic activities of the as-prepared Fe3O4@TA@Au were investigated by spectroscopically monitoring the reduction of 4-nitrophenol (4-NP) and methylene blue (MB), which could be achieved within several minutes with an excess of NaBH4. The impact of the Fe3O4 size on the overall catalytic ability of the Fe3O4@TA@Au was systematically studied. The reaction rate constants of the Fe3O4-20 nm@TA@Au for 4-NP and MB reduction were 0.432 and 0.543 min-1, respectively. For the Fe3O4-200 nm@TA@Au nanocomposite, the optimized reaction rate constants for 4-NP and MB reduction were 3.09 and 0.441 min-1, respectively. Due to magnetic separation, the Fe3O4@TA@Au could be easily harvested and recycled. After five recycling cycles, the catalytic ability remained over 90%, and the recycling process could be completed in several minutes, highlighting its potential as a catalyst for 4-NP and MB removal.

Sensitive colorimetric detection of ochratoxin A by a dual-functional Au/Fe3O4 nanohybrid-based aptasensor.

A novel colorimetric aptasensor based on a Au/Fe3O4 nanohybrid was developed to detect ochratoxin A (OTA). The aptasensor is composed of a free OTA aptamer, a Au/Fe3O4 nanohybrid coated with biotinylated complementary DNA of the OTA aptamer (biotin-cDNA-Au/Fe3O4), and free alkaline-phosphatase-labeled streptavidin (SA-ALP). The Au/Fe3O4 nanohybrid not only immobilizes biotin-cDNA but also magnetically separates SA-ALP from the sample solution. One part of the OTA aptamer sequence hybridizes with biotin-cDNA immobilized on Au/Fe3O4, and the left part of the OTA aptamer sequence covers the biotin and blocks the specific interaction between biotin and SA-ALP. OTA can interrupt the interaction of OTA aptamer binding to biotin-cDNA-Au/Fe3O4 and can inhibit the shielding effect of the OTA aptamer on biotin. The amount of SA-ALP that can be captured by biotin-cDNA-Au/Fe3O4 thus increases with increasing OTA concentration. Through a simple magnetic separation, the collected SA-ALP-linked Au/Fe3O4 can produce a yellow-colored solution in the presence of p-nitrophenyl phosphate (p-NPP). This colorimetric aptasensor can detect OTA as low as 1.15 ng mL-1 with high specificity.