Changes of adjacent segment biomechanics after anterior cervical interbody fusion with different profile design plate: single- versus double-level.

Low-profile angle-stable spacer Zero-P is claimed to reduce the morbidity associated with traditional plate and cage construct (PCC). Both Zero-P and PCC could achieve comparable mid- and long-term clinical and radiological outcomes in anterior cervical discectomy and fusion (ACDF). It is not clear whether Zero-P can reduce the incidence of adjacent segment degeneration (ASD), especially in multi-segmental fusion. This study aimed to test the effect of fusion level with Zero-P versus with PCC on adjacent-segment biomechanics in ACDF. A three-dimensional finite element (FE) model of an intact C2-T1 segment was built and validated. Six single- or double-level instrumented conditions were modeled from this intact FE model using Zero-P or the standard PCC. The biomechanical responses of adjacent segments at the cephalad and caudal levels of the operation level were assessed in terms of range of motion (ROM), stresses in the endplate and disc, loads in the facets. When comparing the increase of adjacent-segment motion in single-level PCC fusion versus Zero-P fusion, a significantly larger increase was found in double-level fusion condition. The fold changes of PCC versus Zero-P of intradiscal and endplate stress, and facet load at adjacent levels in the double-level fusion spine were significantly larger than that in the single-level fusion spine during the sagittal, the transverse, and the frontal plane motion. The increased value of biomechanical features was greater at above segment than that at below. The fold changes of PCC versus Zero-P at adjacent segment were most notable in flexion and extension movement. Low-profile device could decrease adjacent segment biomechanical burden compared to traditional PCC in ACDF, especially in double-level surgery. Zero-P could be a good alternative for traditional PCC in ACDF. Further clinical/in vivo studies will be necessary to explore the approaches selected for this study is warranted.

Designing Nanostructured Metal-Based CO2 Reduction Electrocatalysts.

Capture and conversion of CO2 into value-added chemicals and fuels is one of the most sought-after hot points at the scientific frontier. Driven by renewable energy derived electricity, the heterogeneous electrocatalyic CO2 reduction has attracted intensive interests because of the easy manipulation and high-energy-density fuels supply. Metals with general abundance and robust ability for activating CO2 have been adopted as the core-atom for developing advanced CO2 reduction electrocatalysts. As the dramatic development of nano-technology, the nanostructured metal-based materials become promising candidates for various catalytic systems. In this Review article, a general introduction and principles applied in CO2 electroreduction are summarized and discussed. Then the proposed reaction pathways of the CO2 reduction were classified and elaborated depending on the products. The state of the art advances related to the nanostructured metallic electrocatalysts are addressed as well. At last, the remaining challenges and further prospects for the construction of new nanostructured electrocatalysts for CO2 reduction and improvement of existing ones have been presented.

Mipu1 overexpression protects macrophages from oxLDL-induced foam cell formation and cell apoptosis.

Mipu1 (myocardial ischemic preconditioning upregulated protein 1) is a novel N-terminal Kruppel-associated box (KRAB)/C2H2 zinc finger superfamily protein, that displays a powerful effect in protecting H9c2 cells from oxidative stress-induced cell apoptosis. The present study aims to investigate the effect of Mipu1 overexpression on oxidized low-density lipoprotein (oxLDL)-induced foam cell formation, cell apoptosis, and its possible mechanisms. New Zealand healthy rabbits were used to establish atherosclerosis model, and serum levels of triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol were detected by an automatic biochemical analyzer. Sudan IV staining was used to detect atherosclerotic lesions. The RAW264.7 macrophage cell line was selected as the experimental material. Oil red O staining, high-performance liquid chromatography, and Dil-labeled lipoprotein were used to detect cholesterol accumulation qualitatively and quantitatively, respectively. Flow cytometry was used to determine cell apoptosis. Real-time quantitative polymerase chain reaction (PCR) was used to detect the mRNA expression of the main proteins that are associated with the transport of cholesterol, such as ABCA1, ABCG1, SR-BI, and CD36. Western blot analysis was used to detect the protein expression of Mipu1. There were atherosclerotic lesions in the high-fat diet group with Sudan IV staining. High-fat diet decreased Mipu1 expression and increased CD36 expression significantly at the 10th week compared with standard-diet rabbits. Mipu1 overexpression decreased oxLDL-induced cholesterol accumulation, oxLDL uptake, cell apoptosis, and cleaved caspase-3. Mipu1 overexpression inhibited the oxLDL-induced CD36 mRNA and protein expression, but it did not significantly inhibit the mRNA expression of ABCA1, ABCG1, and SR-BI. Mipu1 overexpression inhibits oxLDL-induced foam cell formation and cell apoptosis. Mipu1 overexpression reduces the lipid intake of macrophages and might be associated with the downregulation of CD36 expression in the presence of oxLDL.

Oxidized high-density lipoprotein promotes maturation and migration of bone marrow derived dendritic cells from C57BL/6J mice.

OBJECTIVE: To explore the influence of oxidized high-density lipoprotein (oxHDL) on the maturation and migration of bone marrow-derived dendritic cells (BMDCs) from C57BL/6J mice. METHODS: The C57BL/6J mice bone marrow cell suspension was prepared and purified. Recombinant granulocyte-macrophage colony-stimulating factor (rmGM-CSF) and recombinant interleukin-4 (rmIL-4) were used to promote monocytes to differentiate and suppress lymphocytes. Then 50 microg/mL oxHDL was added to stimulate BMDCs, using 50 microg/mL high-density lipoprotein (HDL) as homologous protein control, PBS as negative control, and 1 microg/mL lipopolysaccharide (LPS) as positive control. The CD86 and MHCII expression rates were detected with fluorescence-activated cell sorting (FACS). Liquid scintillation counting (LSC) was used in mixed lymphocyte reactions (MLRs) to reflect the ability of BMDCs in stimulating the proliferation of homologous T cells. Levels of cytokines IL-12 and IL-10 were detected by ELISA. The cell migration was evaluated with the transwell system. RESULTS: Compared with PBS group, the expressions of CD86 and MHCII, counts per minute of MLRs, secretion of IL-12 and IL-10, and number of migrated cells in oxHDL group and LPS group significantly increased (all P<0.05), while the increment was less in oxHDL group than LPS group. The number of migrated cells in oxHDL group was about twice of that in HDL group. CONCLUSION: OxHDL may promote the maturation and migration of BMDCs in vitro.