A preparation method for mRNA-LNPs with improved properties.

The properties of mRNA lipid nanoparticles (mRNA-LNPs), including size, empty particles, morphology, storage stability, and transfection potency, are critically dependent on the preparation methods. Here, a Two-step tangential-flow filtration (TFF) method was successfully employed to improve the properties of mRNA-LNPs during the preparation process. This method involves an additional ethanol removal step prior to the particle fusion process. Notably, this innovative approach has yielded mRNA-LNPs with larger particles, a reduced proportion of empty LNPs, optimized storage stability (at least 6 months at 2-8 °C), improved in vitro transfection efficiency, and minimized distribution in the heart and blood in vivo. In summary, this study represents the implementation of the innovative Two-step TFF method in the preparation of mRNA-LNPs. Our findings indicate substantial enhancements in the properties of our mRNA-LNPs, specifically with regard to the percentage of empty LNPs, stability, transfection efficiency, and in vivo distribution. These improvements have the potential to optimize their industrial applicability and expand their clinical use.

[Finite element analysis of the comprehensive impact of scar and maxillary expansion combined with protraction on the development of maxilla with cleft lip and palate after repair operation].

OBJECTIVE: To study the comprehensive impact of scar and maxillary expansion combined with protraction on the development of maxilla with cleft lip and palate after repair operation. METHODS: In the original finite element model of the maxilla with cleft palate, a finite element model of the maxilla with cleft lip and palate was established by using Boolean operation in ANSYS. Scar force after cleft lip and palate repair and maxillary expansion force combined with protraction were added simultaneously to process the stress analysis. RESULTS: Maxillary deformation occurred in the three-dimensional direction. The comparison of displacements was as follows: X-axis>Z-axis>Y-axis. CONCLUSIONS: Maxillary growth is significantly inhibited in the three-dimensional direction under the comprehensive impact of scar and maxillary expansion combined with protraction after repair operation, especially transverse and sagittal growth.

Nicotine induces the production of IL-1ß and IL-8 via the α7 nAChR/NF-κB pathway in human periodontal ligament cells: an in vitro study.

BACKGROUND/AIMS: Tobacco smoking is a major risk factor for the occurrence and progression of periodontitis. We previously demonstrated that nicotine could induce the expression of α7 nicotinic acetylcholine receptors (α7 nAChR) in human and rat periodontal tissues. To further examine the signal pathways mediated by α7 nAChR in periodontal ligament (PDL) cells, we investigated whether nicotine affects interleukin-1ß (IL-1ß) and interleukin-8 (IL-8) via the α7 nAChR/NF-κB pathway in human PDL cells. METHODS: Human PDL cells were pre-incubated with alpha-bungarotoxin (α-BTX) or pyrrolidine dithiocarbamate (PDTC), then cultured with nicotine. Then, we used western blotting, a dual-luciferase reporter, real-time quantitative PCR and an enzyme-linked immunoassay to assess expression of the NF-κB p65 subunit, NF-κB activity and production of IL-1ß and IL-8 in human PDL cells. RESULTS: Compared with the control group, nicotine could significantly induce production of IL-1ß and IL-8 in human PDL cells and cause the similar effects on the expression of the NF-κB p65 subunit and NF-κB activity. CONCLUSION: This study demonstrates that nicotine could induce production of IL-1ß and IL-8 via the α7 nAChR/NF-κB pathway in human PDL cells, providing data for a better understanding of the relationships among smoking, nicotine, and periodontitis.

[Dynamic extraction process of salvianolic acids].

OBJECTIVE: To optimize the dynamic extraction process of salvianolic acids. METHOD: Salvianolic acids was selected as index. The effects of extraction temperature, granularity, solvent multiple, circle value and extraction time were studied on the process of dynamical extraction. The orthogonal experiment was employed to investigate the influence of different parameters. RESULT: The optimal extracting method of salvianolic acids was as follows: temperature was 80 degrees C, granularity was 4 mm, circle value was 30 L x h(-1), solvent multiple was 10 times and extraction time was 150 min. CONCLUSION: By comparison to static extraction, dynamic extraction can improve the extraction efficiency, reduce the solvent and energy consumption, as well as lower the burden of post-processing.

[Studies on application of ultra-filtration to purifying polysaccharides from Rhubarb].

OBJECTIVE: To purify Rhubarb polysaccharides via micro-filtration and ultra-filtration. METHOD: The technology adopted micro-filtration and tubular membrane with different cut-off molecular weights. RESULT: Experiment results showed that the optimum operating conditions were that the ultra-filtration time controlled around 80 min, the temperature was set the 35-40 degrees C, the operating pressure was 0.08-0.12 MPa, the pH was 6-8, and a sample that of polysaccharide was 0.5 times of original concentration. The recovery ratio of the polysaccharides was 53.7%, the concentration could be condensed to 2.73 times compared with the sample liquid. CONCLUSION: The technology was simple and feasible, it can be applied to purify Rhubarb polysaccharides.

[Study on water extraction process of Herba epimedii with microwave technology].

OBJECTIVE: To study, the high polar media-water extraction process of Herba epimedii with the microwave technology. METHOD: The single parameters of extraction process was investigated with dry extract yield and extraction efficiency of icariin as content index. RESULT: Through studying the single parameter, the optimal conditions are as follows: 70% ethanol as wetting solvent, volume of solvent to weight of material equal to 6:1 in wetting, 30 min wetting time, 2.5 min microwave irradiation time, volume of solvent to weight of material equal to 50:1 in extraction process, 10 min microwave-assisted extraction time. CONCLUSION: Compared with conventional methods, microwave-assisted extraction (MAE) after Microwave Pretreament (MP) of raw material was higher extraction efficiency and time-saving.