[Genetic analysis of 45 patients with suspected Lynch syndrome using next-generation sequencing].

Objective: To evaluate the value of next generation sequencing (NGS) in the genetic testing of Lynch syndrome. Methods: Immunohistochemical method was used to detect the expressions of DNA mismatch repair (MMR) proteins, including MutL homolog 1 (MLH1), PMS1 homolog 2 (PMS2), MutS homolog 2 (MSH2) and MutS homolog 6 (MSH6) in colorectal cancer, gastric cancer and endometrial cancer tissues collected from Shandong Provincial Hospital between 2016 and 2018. The genomic DNA of 45 patients who were suspected with Lynch syndrome was extracted from non-cancerous tissue paraffin samples, which were postoperatively confirmed by microscope. The mutations of 12 genes including MLH1 and MSH2 were detected using NGS. The germline mutant sites and significance were analyzed by bioinformatics technology and further confirmed by using Sanger sequencing. Results: The immunohistochemical results showed that the 45 cases of suspected Lynch syndrome included 22 cases of MLH1 and PMS2 deficient expression, 16 cases of MLH2 and MSH6 deficient expression, and 7 cases of MMR proteins normal expression. The NGS result showed that 28 cases of adjacent sample from colon cancer patients included 4 cases of MLH1 pathogenic mutation, 1 case of suspected MLH1 mutation, 2 cases of MLH2 pathogenic mutation, 2 cases of suspected MLH2 mutation. No MMR gene mutation was found in adjacent samples of 6 cases of rectal cancer, 6 cases of gastric cancer and 7 cases of colorectal cancer with MMR normal expression. One case of MLH1 or MHL2 pathogenic mutation and one case of MLH1 suspected mutation was detected in adjacent samples of 5 cases of endometrial cancer. Moreover, NGS also detected many other genes mutations and unreported gene mutation sites. Pathogenic and suspected MLH1 and MSH2 mutations were verified by Sanger sequencing. Conclusions: High-throughput NGS is a quick, accurate and reliable technique to identify gene variants in suspected Lynch syndrome patients. It has a wide application prospect for gene testing of tumors associated with Lynch syndrome.

The fabrication of highly conductive and flexible Ag patterning through baking Ag nanosphere-nanoplate hybrid ink at a low temperature of 100 °C.

With the aim of developing highly conductive ink for flexible electronics on heat-sensitive substrates, Ag nanospheres and nanoplates were mixed to synthesize hybrid inks. Five kinds of hybrid ink and two types of pure ink were written to square shape on Epson photo paper using rollerball pens, and sintered at a low temperature (100 °C). The microstructure, electrical resistivity, surface porosity, hardness and flexibility of silver patterns were systematically investigated and compared. It was observed that the optimal mixing ratio of nanospheres and nanoplates was 1:1, which equipped the directly written pattern with excellent electrical and mechanical properties. The electrical resistivity was 0.103 µΩ · m, only 6.5 times that of bulk silver. The enhancement compared to pure silver nanospheres or nanoplates based ink was due to the combined action of nanospheres and nanoplates. This demonstrates a valuable way to prepare Ag nanoink with good performance for printed/written electronics.

Ag-graphene hybrid conductive ink for writing electronics.

With the aim of preparing a method for the writing of electronics on paper by the use of common commercial rollerball pens loaded with conductive ink, hybrid conductive ink composed of Ag nanoparticles (15 wt%) and graphene-Ag composite nanosheets (0.15 wt%) formed by depositing Ag nanoparticles (∼10 nm) onto graphene sheets was prepared for the first time. Owing to the electrical pathway effect of graphene and the decreased contact resistance of graphene junctions by depositing Ag nanoparticles (NPs) onto graphene sheets, the concentration of Ag NPs was significantly reduced while maintaining high conductivity at a curing temperature of 100 ° C. A typical resistivity value measured was 1.9 × 10(-7) Ω m, which is 12 times the value for bulk silver. Even over thousands of bending cycles or rolling, the resistance values of writing tracks only increase slightly. The stability and flexibility of the writing circuits are good, demonstrating the promising future of this hybrid ink and direct writing method.

Pressure-assisted low-temperature sintering for paper-based writing electronics.

With the aim of preparing paper-based writing electronics, a kind of conductive pen was made with nano-silver ink as the conductive component and a rollerball pen as the writing implement. This was used to direct-write conductive patterns on Epson photo paper. In order to decrease the sintering temperature, pressure was introduced to enhance the driving forces for sintering. Compared with hot sintering without pressure, hot-pressure can effectively improve the conductivity of silver coatings, reduce the sintering time and thus improve productivity. Importantly, pressure can achieve a more uniform and denser microstructure, which increases the connection strength of the silver coating. At the optimum hot-pressure condition (sintering temperature 120 ° C/sintering pressure 25 MPa/sintering time 15 min), a typical measured resistivity value was 1.43 × 10⁻7 Ω m, nine greater than that of bulk silver. This heat treatment process is compatible with paper and does not cause any damage to the paper substrates. Even after several thousand bending cycles, the resistivity values of writing tracks by hot-pressure sintering stay almost the same (from 1.43 × 10⁻7 to 1.57 × 10⁻7 Ω m). The stability and flexibility of the writing circuits are good, which demonstrates the promising future of writing electronics.

Protective effect of MAPK signaling pathway mediated by ITGB3 gene silencing on myocardial ischemia-reperfusion injury in mice and its mechanism.

OBJECTIVE: To explore the effect of integrin ß3 (ITGB3) gene silencing mediated mitogen-activated protein kinase (MAPK) signaling pathway on myocardial ischemia-reperfusion injury (MIRI) in mice. MATERIALS AND METHODS: MIRI mice model was established, and myocardial tissues of MIRI mice and sham operation group mice were extracted. Hematoxylin-Eosin (HE) staining was used to observe the pathological changes of myocardial tissue; terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining was used to detect the apoptosis of myocardial cells; ELISA method was used to detect the levels of interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-α in the two groups. The infarct size was measured by TTC staining. Myocardial cells of MIRI model mice were isolated and cultured, and then grouped and transfected. The cells were transfected with the grouping of MIRI group, negative control (NC) group, MAPK signal pathway agonist Anisomycin group, MAPK signal pathway inhibitor SB203580 group, ITGB3-siRNA group, SB203580 + ITGB3-siRNA group. Real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot were used to detect the mRNA and protein expressions of ITGB3, p38MAPK/p-p38MAPK, GSK-3ß/p-GSK-3ß, Cx43/p-Cx43, pro-apoptotic factor Bax and anti-apoptotic factor Bcl-2. 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay was used to detect cell proliferation and flow cytometry to detect cell apoptosis. RESULTS: The expression of ITGB3 in myocardial tissue of MIRI mice was significantly higher than that of sham operated mice (p<0.05). Compared with the sham operation group, the apoptosis rate of myocardial cells in MIRI group was significantly increased, the expression levels of IL-1, IL-6 and TNF-α were significantly increased, and the myocardial infarction area was significantly increased (all p<0.05). Compared with MIRI and NC groups, ITGB3 mRNA and protein expression levels in ITGB3-siRNA group and SB203580 + ITGB3-siRNA group were significantly decreased (all p<0.05), but no significant change was found in Anisomycin group and SB203580 group (p>0.05). Furthermore, ITGB3-siRNA group and Anisomycin group had markedly decreased mRNA and protein expressions of ITGB3 and Bax, increased mRNA and protein expressions of p38MAPK/p-p38MAPK, GSK-3ß/p-GSK-3ß, Cx43/p-Cx43 and Bcl-2, as well as increased cell proliferation and decreased cell apoptosis (all p<0.05); SB203580 group indicated an opposite result with Anisomycin group; while SB203580 + ITGB3-siRNA revealed none significant statistical difference. In addition, compared with ITGB3-siRNA group, SB203580 + ITGB3-siRNA group showed significantly upregulated mRNA and protein expressions of Bax, downregulated mRNA and protein expressions of p38MAPK/p-p38MAPK, GSK-3ß/p-GSK-3ß, Cx43/p-Cx43 and Bcl-2, as well as decreased cell proliferation and increased cell apoptosis (all p<0.05). CONCLUSIONS: Silencing ITGB3 gene expression can promote the activation of MAPK signaling pathway, elevate the phosphorylation of GSK-3ß and Cx43 in the downstream, promote the proliferation of mouse myocardial cells, inhibit myocardial cell apoptosis and inflammatory reaction, and thus have protective effect on MIRI in mice.

LncRNA MEG3 promotes the sensitivity of vincristine by inhibiting autophagy in lung cancer chemotherapy.

OBJECTIVE: Lung cancer is one of the most common malignancies worldwide, the morbidity and mortality of which have been on rising in recent years. Moreover, lncRNAs have been implicated in the development of various cancers, as well as cancer treatment and prognosis. In this study, long non-coding RNA (lncRNA) MEG3, an identified tumor suppressor, was explored for its role in the chemotherapy of lung cancer. MATERIALS AND METHODS: All cases were divided into (I+II) group and (III+IV) group according to different stages of tumor node metastasis (TNM), and were divided into sensitive group and insensitive group according to chemotherapy sensitivity. A549 and H292 cells were selected as the resistant cell and non-resistant lung cancer cells. Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was performed to detect the expression of MEG3. After transfection with overexpression plasmid pcDNA-MEG3 or/and different concentrations of vincristine, cell viability and proliferation were measured by cell counting kit-8 (CCK-8) assay and plate cloning assay, respectively. Western blotting was used to analyze the expressions of autophagy-related proteins. RESULTS: In vivo, lncRNA MEG3 was significantly lower in III+IV group and insensitive group than that in I+II group and sensitive group. In vitro, MEG3 expression in resistant cells was significantly lower than that in non-resistant cells. Overexpression of MEG3 significant inhibited the viability and proliferation of both resistant and non-resistant lung cancer cells. Western blot results showed that autophagy level was higher in resistant cells than that in non-resistant cells, while overexpression of MEG3 significantly reduced the expression of autophagy-related proteins. CCK-8 results also indicated that the cell viability was negatively correlated with the dose of vincristine, while the viability of drug-resistant cells was higher than that of non-drug resistant cells after the treatment of vincristine. The vitality of both cells decreased in a concentration-dependent manner after combined treatment with vincristine and MEG3. CONCLUSIONS: Our data indicated that lncRNA MEG3 showed a low expression in chemotherapy-sensitive lung cancer tissues, and overexpression of lncRNA MEG3 attenuated autophagy level, thus increasing the sensitivity of vincristine in chemotherapy of lung cancer.

X-ray reflectivity study on the structure and phase stability of mixed phospholipid multilayers.

Vertically oriented multilayers composed of two saturated phospholipids, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoserine (DPPS), were deposited on silicon. X-ray reflectivity was used to investigate the structures of the variously mixed phospholipid multilayers as a function of composition. Then, the phase stability was investigated at various annealing temperatures under humid conditions. The results indicated that the lipid spacing of the mixed phospholipid multilayers varied systematically as a function of the DPPC/DPPS ratio and that no macroscopic phase separation occurred during the annealing process under both dry and humid conditions.