Establishment of a reporter system for estimating activation of human hepatic stellate cells based on COL1A1 promoter and enhanced green fluorescent protein / 北京大学学报(医学版)

OBJECTIVE@#To establish a visual reporting system for evaluating the activity of collagen Ⅰ α 1 chain (COL1A1) gene promoter in immortalized human hepatic stellate cells, so as to estimate the activation status of the cells and provide a new cell model for the screening and study of anti-hepatic fibrosis drugs.@*METHODS@#The promoter sequence of human COL1A1 was amplified from the genomic DNA of human hepatocarcinoma cell line HepG2. Based on the pLVX-AcGFP1-N1 plasmid, the recombinant plasmid pLVX-COL1A1-enhanced green fluorescent protein (EGFP) was constructed, in which the enhanced green fluorescent protein gene expression was regulated by the COL1A1 promoter. The monoclonal cell line was acquired by stably transfecting pLVX-COL1A1-EGFP into the immortalized human hepatic stellate cell line LX-2 by the lentivirus packaging system and screening. The cell line was treated with transforming growth factor-β1 (TGF-β1) or co-treated with TGF-β1 and drugs with potential anti-hepatic fibrosis effects. The EGFP fluorescence intensity in cells was analyzed by the fluorescence microscope and ImageJ 1.49 software using a semi-quantitative method. The COL1A1 and EGFP mRNA were detected by reverse transcription real-time quantitative PCR (RT-qPCR), and corresponding proteins were detected by Western blot.@*RESULTS@#The recombinant plasmid pLVX-COL1A1-EGFP with the expression of EGFP regulated by COL1A1 promoter was successfully constructed. Kozak sequence was added to enhance the expression of EGFP, which was identified by double digestion and sequencing. The LX-2 monoclonal cell line LX-2-CE stably transfected with pLVX-COL1A1-EGFP was obtained. After co-treatment with TGF-β1 and 5 μmol/L dihydrotanshinone Ⅰ with potential anti-hepatic fibrosis effect for 24 h, the total fluorescence intensity and the average fluorescence intensity of LX-2-CE were lower than those in TGF-β1 single treatment group (P < 0.05), the intracellular mRNA and protein levels of COL1A1 and EGFP were also lower than those in the TGF-β1 single treatment group (P < 0.05).@*CONCLUSION@#A reporter system for estimating activation of hepatic stellate cells based on COL1A1 promoter regulated EGFP expression is successfully constructed, which could visually report the changes in COL1A1 expression, one of the activation-related markers of hepatic stellate cells, in vitro. It provides a new cell model for the screening and study of anti-hepatic fibrosis drugs.

Implant prosthesis design scheme for sophisticated congenital partial edentia / 华西口腔医学杂志

Sophisticated congenital partial edentia are often accompanied by severe shortage of bone height and width due to the absence of permanent teeth; such condition will affect implant placement. This study aimed to display the different typical implant rehabilitation schemes we designed for sophisticated congenital partial edentia cases with severely atrophic alveolar bone.

Expression of cellular fibronectin mRNA in adult periodontitis and peri-implantitis: a real-time polymerase chain reaction study / 国际口腔科学杂志·英文版

Cellular fibronectin (cFn) is a type of bioactive non-collagen glycoprotein regarded as the main substance used to maintain periodontal attachment. The content of cFn in some specific sites can reflect the progress of periodontitis or peri-implantitis. This study aims to evaluate the expression of cFn messenger RNA (mRNA) in tissues of adult periodontitis and peri-implantitis by real-time fluorescent quantitative polymerase chain reaction (PCR) and to determine its clinical significance. A total of 30 patients were divided into three groups of 10: healthy, adult periodontitis and peri-implantitis. Periodontal tissue biopsies (1 mm×1 mm×1 mm) from each patient were frozen in liquid nitrogen. Total RNA was extracted from these tissues, and the content, purity and integrity were detected. Specific primers were designed according to the sequence, and the mRNA expression levels of cellular fibronectin were detected by real-time PCR. The purity and integrity of the extracted total RNA were both high, and the specificity of amplified genes was very high with no other pollution. The mRNA expression of cFn in the adult periodontitis group (1.526±0.441) was lower than that in the healthy group (3.253±0.736). However, the mRNA expression of cFn in the peri-implantitis group (3.965±0.537) was significantly higher than that in the healthy group. The difference revealed that although both processes were destructive inflammatory reactions in the periodontium, the pathomechanisms were different and the variation started from the transcription level of the cFn gene.

A clinical study of immediate dental implant and immediate restoration / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the clinical results of immediate implant and immediate restoration and to discuss the applying principles of these techniques.</p><p><b>METHODS</b>Fourteen cases underwent immediate implant surgery for 37 dental implants immediately after the teeth or roots were extracted. Among them, 6 cases (14 implants) received immediate restoration after implant placement. The second stage operation and final restoration were performed 4 months on average postoperatively, and the mean follow-up time was 22 months.</p><p><b>RESULTS</b>Two implants from 1 case were lost at 3 weeks after immediate implant and immediate restoration. The rest cases achieved good clinical results. Accumulative 4-year survival rate was 94.6%.</p><p><b>CONCLUSIONS</b>The result of immediate implant and immediate restoration is predictable if the cases are properly selected.</p>