Overexpression of HMGB1 A-box reduced lipopolysaccharide-induced intestinal inflammation via HMGB1/TLR4 signaling in vitro

AIM: To investigate the inhibitory effects and mechanism of high mobility group box(HMGB)1 A-box in lipopolysaccharide(LPS)-induced intestinal inflammation.METHODS: Overexpression of HMGB1 A-box in human intestinal epithelial cell lines(SW480 cells) was achieved using the plasmid p EGFP-N1. HMGB1 A-box-overexpressing SW480 cells were stimulated with LPS and co-culturing with human monocyte-like cell lines(THP-1 cells) using a Transwell system, compared with another HMGB1 inhibitor ethyl pyruvate(EP). The m RNA and protein levels of HMGB1/toll-like receptor(TLR) 4 signaling pathways [including HMGB1, TLR4, myeloid differentiation factor88(MYD88), Phosphorylated Nuclear Factor κB(p NF-κB) p65] in the stimulated cells were determined by realtime polymerase chain reaction and Western blotting. The levels of the proinflammatory mediators [including HMGB1, interleukin(IL)-1β, IL-6 and tumor necrosis factor(TNF)-α] in the supernatants of the stimulated cells were determined by ELISA.RESULTS: EP downregulated the m RNA and protein levels of HMGB1, inhibited the TLR4 signaling pathways(TLR4, MYD88 and p NF-κB p65) and reduced the secretion of proinflammatory mediators(HMGB1, IL-1β, IL-6 and TNF-α) in the SW480 and THP-1 cells activated by LPS but not in the unstimulated cells. Activated by LPS, the overexpression of HMGB1 A-box in the SW480 cells also inhibited the HMGB1/TLR4 signaling pathways and reduced the secretion of these proinflammatory mediators in the THP-1 cells but not in the transfected and unstimulated cells. CONCLUSION: HMGB1 A-box, not only EP, can reduce LPS-induced intestinal inflammation through inhibition of the HMGB1/TLR4 signaling pathways.

Furazolidone-based triple and quadruple eradication therapy for Helicobacter pylori infection

AIM: To evaluate the efficacy of furazolidone-based triple and quadruple therapy in eradicating Helicobacter pylori (H. pylori) in a multi-center randomized controlled trial.

DNMT3B 579 G>T promoter polymorphism and risk of esophagus carcinoma in Chinese

AIM:To investigate the relationship between 579 G>T polymorphisms in the DNMT3B gene, which is involved in de novo methylation and associated with the risk of esophagus cancer (EC) in Chinese. METHODS:DNMT3B 579 G>T genotypes were determined by PCR-RFLP in 194 EC patients and 210 healthy controls matched for age and sex, who did not receive radiotherapy or chemotherapy for newly diagnosed and histopathologically confirmed EC. RESULTS:In control subjects, the frequency of T/T and G/T genotypes, and T and G alleles was 81.4%, 18.1%, 90.05% and 9.55%, respectively. The distribution of genotypes and allelotypes in the EC patients was not significantly different from that in the controls. When stratified by sex and age, there was still no significant association between the risks of EC and GT and GG genotypes. This study also showed a distinct difference in the distribution of DNMT3B and single nucleotide polymorphism (SNP) between Chinese and Koreans.CONCLUSION:DNMT3B 579 G>T polymorphism may not be a stratification marker to predict the susceptibility to EC, at least in Chinese. DNMT3B promoter SNP is diverse in ethnic populations.

Applying dynamic light scattering to investigate the self-assembly process of DNA nanostructures

Understanding the dynamic assembly process of DNA nanostructures is important for developing novel strategy to design and construct functional devices.In this work,temperature-controlled dynamic light scattering(DLS)strategy has been applied to study the global assembly process of DNA origami and DNA bricks.Through the temperature dependent size and intensity profiles,the self-assembly process of various DNA nanostructures with different morphologies have been well-studied and the temperature transition ranges could be observed.Taking advantage of the DLS information,rapid preparation of the DNA origami and the brick assembly has been realized through a constant temperature annealing.Our results demonstrate that the DLS-based strategy provides a convenient and robust tool to study the dynamic process of forming hieratical DNA structures,which will benefit understanding the mechanism of self-assembly of DNA nanostructures.

The investigation of the stability of DNA-b-PPO vesicles formed through frame guided assembly

Frame-guided assembly is a novel assembly method which can control the shape and size of vesicles accurately. It has been reported that the DNA-b-PPO vesicles could be stable over two weeks. In this communication we have introduced restriction sites of EcoR1 in the interior DNA scaffold to the formed vesicles in order to further study their stability. Dynamic light scattering(DLS), transmission electron microscope(TEM) and fluorescence spectrum were used to characterize the digestion process. The final results revealed that the vesicles were still stable even after two weeks cultivated with EcoR1, which suggests potential in future biological applications.

New design of sense amplifier for EEPROM memory

We present a new sense amplifier circuit for EEPROM memory. The topology of the sense amplifier uses a voltage sensing method,having low cost and low power consumption as well as high reliability. The sense amplifier was implemented in an EEPROM realized with an SMIC 0.35-μm 2P3M CMOS embedded EEPROM process. Under the condition that the power supply is 3.3 V,simulation results showed that the charge time is 35 ns in the proposed sense amplifier,and that the maximum average current consumption during the read period is 40 μA. The novel topology allows the circuit to function with power supplies as low as 1.4 V. The sense amplifier has been implemented in 2-kb EEPROM memory for RFID tag IC applications,and has a silicon area of only 240 μm2.