Pure-silica MFI zeolite (silicalite-1) membranes exhibit great potential in the separation of an ethanol/water mixtures. For synthesis of silicalite membranes, however, conventional supports such as α-Al 2 O 3 and mullite have aluminum element leaching out and entering into a zeolite structure, which would reduce the hydrophobicity of the zeolite layer and thus affect the separation performance for ethanol selectivity. In this paper, we prepared silicalite membranes on hollow fiber substrates fabricated with yttria stabilized zirconia (YSZ) without aluminum. The influence of seed size, synthesis parameters, and substrates was investigated. The as-synthesized membranes were characterized by scanning electron microscopy (SEM), electron probe microanalyzer (EPMA), infrared spectrum analysis (IR), and X-ray diffraction (XRD). A thin MFI zeolite layer with a thickness of about 3 μm could be formed on the support, which exhibited highly selective to ethanol over water. A high flux of 7.4 kg m −2 h −1 with the separation factor (ethanol/water) of 47 was achieved on the as-made membrane for separating 5 wt % ethanol/water at 60 °C.
MicroRNAs (miRNAs) are considered to be critical mediators of gene expression with respect to tumor progression, although their role in ischemia-induced angiogenesis is poorly characterized, including in peripheral arterial disease (PAD). Furthermore, the underlying mechanism of action of specific miRNAs in PAD remains unknown. Reverse transcription-quantitative polymerase chain reaction analysis revealed that microRNA-93 (miR-93) was significantly upregulated in patients with PAD and in the EA.hy926 endothelial cells in response to hypoxia. Additionally, miRNA (miR)-93 promoted angiogenesis by enhancing proliferation, migration and tube formation. Cyclin dependent kinase inhibitor 1A (CDKN1A), verified as a potential target gene of miR-93, was inhibited by overexpressed miR-93 at the protein and mRNA expression levels. Furthermore, a hind-limb ischemia model served to evaluate the role of miR-93 in angiogenesis in vivo , and the results demonstrated that miR-93 overexpression enhanced capillary density and perfusion recovery from hind-limb ischemia. Taken together, miR-93 was indicated to be a promising target for pharmacological regulation to promote angiogenesis, and the miR-93/CDKN1A pathway may function as a novel therapeutic approach in PAD.
Effect of revascularization in the treatment of thromboangiitis obliterans (TAO) and the predictive value of serum vascular endothelial growth factor (VEGF), interleukin-1 (IL-1) and tumor necrosis factor-α (TNF-α) of risk factors of amputation were investigated. From April 2012 to August 2015, a total of 117 patients with TAO admitted to the First Hospital of Lanzhou University were selected. Patients treated with revascularization combined with prostaglandin sodium and cilostazol were enrolled in group A (67 patients), and patients treated with sodium and cilostazol were enrolled in group B (50 patients). The clinical efficacy was evaluated by calculating the intermittent claudication distance and the ankle brachial index (ABI) of patients. The occurrence probability of nausea and vomiting, skin pruritus, abdominal pain, coagulation abnormalities and amputation were recorded. The concentration of serum VEGF, IL-1 and TNF-α were measured using enzyme-linked immunosorbent assay (ELISA). After treatment, the intermittent claudication distance, ABI and efficiency of group A was markedly higher than that of group B (P<0.05). After treatment, serum VEGF concentration in group A was clearly higher than that in group B (P<0.05), and IL-1 and TNF-α levels were much lower than those in group B (P<0.05). The amputation rate in group A was significantly lower than that in group B (P<0.05). Patients with amputation in both groups were enrolled in the study group (24 cases), and those without amputation were included in the control group (93 cases). The serum VEGF concentration in the study group before treatment was significantly lower than that in the control group (P<0.05), while IL-1 and TNF-α levels were significantly higher than those of the control group (P<0.05). In conclusion, pretreatment serum VEGF, IL-1 and TNF-α had a positive diagnostic value for poor prognosis of patients with amputation, and low concentration of VEGF and higher concentration of IL-1 and TNF-α are the risk factors for amputations in patients with TAO.
The effects of different doses of folic acid and vitamin B12 on rabbits with deep vein thrombosis (DVT) and hyperhomocysteinemia were investigated. In total, 60 New Zealand rabbits were divided into untreated control, low-dose and high-dose groups. After inducing DVT, hemorheology and coagulation indexes were measured 3 and 10 days later. We found that both treatment groups performed better than the control group, and the high-dose performed better than the low-dose. Ten days after thrombosis, the levels of Hcy and D-dimer were lower in the high-dose group. Moreover, the changes of lower extremity deep venous thrombosis were significantly reduced in both high- and low-dose groups, but the high-dose group showed the most improvement. The effective rate of the high-dose group was 100%, higher than the rate in the low-dose and control groups. Overall, high-dose of folic acid and vitamin B12 can significantly improve plasma Hcy, coagulation indexes, and pathological changes in the venous thrombosis of the lower extremity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.