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As a class I carcinogen, arsenic has been reported to cause diseases accompanied by circRNAs regulating proliferation and apoptosis at the molecular level, but whether circP50 (circBase ID: hsa_circ_0008012) does the same has not been demonstrated. The aim of this study is to provide the basis for anti-lung cancer mechanism research, by studying the expression of circP50 under arsenic-induced conditions, and the effect and mechanism on the proliferation and apoptosis of A549 cells based on the circP50 knockdown models. To explore whether the circP50 is responsive to arsenic exposure, the qRT-PCR was applied to discover that the relative expression of circP50 in A549 cells increased only with increasing NaAsO

Objective: To explore the relationship between Polymorphism of FEN1 Gene and DNA Damage of Cytb Gene in Arsenic-Exposed Workers. Methods: The content of arsenide in urine of 79 arsenic-exposed workers and 24 agricultural workers was detected by an atomic absorption spectrophotometer. The DNA damage level of Cytb gene and the polymorphism of FEN1 gene in peripheral blood were detected by polymerase chain reaction. Results: The increased exposure to arsenic caused DNA damage of Cytb gene, resulting in an increase in the content of arsenide in urine and hypomethylation of arsenic metabolism. Meanwhile, there was a potential positive correlation between the FEN1 rs174538 AA or GA+AA allele and the DNA damage level of Cytb gene. Conclusions: The DNA damage of Cytb gene caused by arsenic exposure is related to FEN1 gene polymorphism, the content of arsenide in urine and the level of arsenic methylation metabolism.

Cerium oxide (CeO

The modification of Au nanoparticles can improve the antioxidant activity of CeO2, however, nano Au/CeO2 has also met some problems such as low atomic utilization, the limit of reaction conditions, and high cost. Au single atom catalysts can well solve the above-mentioned problems, but there are some contradictory results about the activity of single atom Au1/CeO2 and nano Au/CeO2. Here, we synthesized rod-like Au single atom Au/CeO2 (0.4% Au1/CeO2) and nano Au/CeO2 (1% Au/CeO2, 2% Au/CeO2 and 4% Au/CeO2), and their antioxidant activity from strong to weak is 0.4% Au1/CeO2, 1% Au/CeO2, 2% Au/CeO2 and 4% Au/CeO2, respectively. The higher antioxidant activity of 0.4% Au1/CeO2 is mainly due to the high Au atomic utilization ratio and the stronger charge transfer between Au single atoms and CeO2, resulting in the higher content of Ce3+. Due to the coexistence of Au single atoms and Au NPs in 2% Au/CeO2, the antioxidant activity 2% Au/CeO2 is higher than that of 4% Au/CeO2. And the enhancement effect of Au single atoms was not affected by the concentration of ·OH and material concentration. These results can promote the understanding of the antioxidant activity of 0.4% Au1/CeO2 and promote its application.

Arsenic (As) exposure has been a global public health concern for hundreds of millions worldwide. LncRNA APTR (Alu-mediated p21 transcriptional regulator) plays an essential role in tumor growth and development. However, its function in arsenic-induced toxicological responses is still unknown. In this study, we found that the expressions of all transcripts and the transcript NR 134251.1 of APTR were increased in a dose-dependent manner in 16HBE cells treated with sodium arsenite (NaAsO2). Silencing the transcript NR 134251.1 of APTR inhibited cell proliferation and induced apoptosis. However, silencing all transcripts of APTR had the opposite function to the transcript NR 134251.1. Then we examined the protein level of the proliferation and apoptosis-related genes after silencing the transcript NR 134251.1 of APTR. The results showed that silencing the transcript NR 134251.1 of APTR up-regulated the expression of transcription factor E2F1 and regulated its downstream genes involved in proliferation and apoptosis, including p53, phospho-p53-S392, phospho-p53-T55, p21, Cyclin D1, PUMA, Fas, Bim, BIK, Caspase-3, Caspase-7, and Cyt-c. In conclusion, arsenic induced APTR expression and the transcript NR 134251.1 of APTR have an opposite function to all transcripts, providing a theoretical basis for the prevention and treatment of arsenic exposure.

We have designed and synthesized a novel cationic polymer, poly[(2-acryloyl)ethyl (p-boronic acid)benzyl diethylammonium bromide], whose p-boronic acid benzyl can be converted to anionic poly(acrylic acid). Herein, the complexation of the cationic polymer with DNA and their disassembly triggered by reactive oxygen species were analyzed in real time by a high-resolution surface plasmon resonance. We have found that both single-stranded DNA and double-stranded DNA could bind to cationic polymer and immobilized onto the Au surface via electrostatic interactions with the binding constant 1.4 × 1011 M–1 for double-stranded DNA and 1.0 × 1011 M–1 for single-stranded DNA. Upon adding H2O2, the adsorbed DNA was quickly released due to cationic polymer turned into negatively charged poly(acrylic acid). Thus, this study confirmed that the polymer that can undergo positive to negative charge-reversal and provide the quick release of DNA for effective gene transfection.

Previous reports have noted that exposed crystal planes could affect the antioxidant activity of nanocerias, although the synthesized nanocerias used in those studies had different exposed crystal planes, as well as different sizes and morphologies. In order to better understand the effect of the crystal planes on the antioxidant activity of the materials, two types of nanocerias with similar morphology and size distribution but different crystal planes were synthesized using the hydrothermal method (CeO2–H) and the ultrasonic template method (CeO2–U). The antioxidant activities of the nanocerias were further explored within different ·OH concentrations in the reaction system. The experimental results showed that there is an obvious difference in the antioxidant activity of the two types of nanocerias in the lower free radical concentration system due to the effects of exposed crystal planes. CeO2–U, with more active crystal planes (100), had stronger antioxidant activity. However, with the increase in the ·OH concentration in the reaction system, the difference in the antioxidant activity of the two nanocerias decreased. This research will increase our understanding of the antioxidant activity of the exposed crystal planes on nanocerias.

Gold nanoparticle (AuNP) modification shows great advantages in improving the antioxidant activity of nanoCeO

Abnormal O-linked-N-acetylglucosamine (O-GlcNAc) concentrations have been associated with a variety of diseases (e.g., cancer, Alzheimer's disease, cardiovascular disease, etc.). However, O-GlcNAc detection is complicated, time-consuming and has poor specificity, therefore, the accurate detection of O-GlcNAc is difficult. In this study, an accurate and sensitive surface plasmon resonance (SPR) biosensor for O-GlcNAc detection that is based on β-D-N-acetylglucosaminidase (OGA) and Au nanoparticles (AuNPs) was developed. In this strategy, AuNPs were used to amplify the SPR signal and improve the biosensor's sensitivity; OGA was used to cleave O-GlcNAc from O-GlcNAcylated biomolecules. The interaction between AuNPs labeled wheat germ agglutinin (AuNPs/WGA) and O-GlcNAcylated biomolecules on a modified Au film treated with and without OGA was recorded by SPR. The change of the SPR signal moves linearly with the amount of O-GlcNAc on the Au film and thus could be used for the detection of O-GlcNAc. By recording the difference of the SPR signals, this method can avoid disturbances from other sugars and nonspecific adsorption of AuNPs and thus enable the accurate detection of O-GlcNAc. The accurate detection range of O-GlcNAc was 4.65 × 10−12 to 4.65 × 10−7 M which was obtained by quantifying the amount of a standard O-GlcNAcylated peptide (O-GlcNAc-CREB), and the detection limit is 4.65 × 10−13 M. More importantly, the strategy was successfully used to detect O-GlcNAc in a real α-crystallin protein, cancer cell lysates and blood samples with satisfactory results. The study's results imply that this accurate and sensitive method has the potential to be applied in the early clinical diagnosis of O-GlcNAc-related diseases.

AuNP-modified CeO2 nanomaterials with three different morphologies were prepared and their antioxidant abilities were evaluated by the UV method; then, the mechanism of the effect of AuNPs was further explored. It was found that AuNPs’ effect on the antioxidant properties of CeO2 varied with different morphologies and sample concentrations. At lower concentrations, AuNPs improved the antioxidant abilities of CeO2 nanorods and nanoparticles and reduced that of CeO2 nanocubes. However, at higher concentrations, the antioxidant activities of Au/CeO2 nanorods and nanoparticles were decreased and that of Au/CeO2 nanocubes was enhanced. It was observed that AuNPs promoted the generation of Ce3+ on the surfaces of CeO2 nanorods and nanoparticles, causing increased antioxidant activity, while they inhibited the generation of Ce3+ on nanocubes, accompanied with decreased activity. In addition, at higher concentrations, more exposed active sites on the surfaces of Au/CeO2 nanorods and nanoparticles were hidden due to severe aggregation, resulting in decreased antioxidant activity compared to CeO2; less aggregation was found for Au/CeO2 nanocubes, and their antioxidant activity was better than that of CeO2. Furthermore, the behaviour of nanocubes was found to be opposite to that of nanorods and nanoparticles, possibly attributed to the particularity of (1 0 0) crystal planes, which may change the way that electrons transfer at the interface.

Abnormal O-linked N-acetylglucosamine (O-GlcNAc) concentrations have been associated with many diseases, but the lack of accurate detection method limited O-GlcNAc to be used as a biomarker in clinical diagnosis. Then O-GlcNAc transferase (OGT) has drawn researchers’ attention as it closed related to the level of O-GlcNAc and be considered to be a promising new target for diseases diagnosis. Nevertheless, the existing OGT detection methods are either need labeling or the sensitity can not meet the needs of clinic testing. Herein, a label-free and sensitive SPR biosensor was developed for accurate detection of OGT based on a multi-functional peptide. The designed peptide contains three recognition sites, one is the cleavage site of protease K, one is the O-GlcNAcylated site by OGT, and another is six histidine which be used as the signal report probe to recognize Ni2+. The immobilized peptide would be cleavaged by proteinase K, then the His-tag residue part will leave the surface of Au film, resulting less His-tag could bind to Ni2+ and a small SPR signal would be record. If the peptide is O-GlcNAcylated by OGT, the cleaving reaction would be limited due to the adjacent site of O-GlcNAcylation. Then more His-tag can be left on the Au film and a bigger SPR signal could be record, this signal is associated with the concentration of OGT. Utilizing the change of the peptide configuration as a signal report probe for OGT detection not only avoids labeling of peptide, but also makes the method more sensitive. The determination linear range of OGT is from 2.00 × 10−13 to 5.00 × 10−8 M with a detection limit of 1.19 × 10−13 M, and the separation of two enzyme reactions ensured the high selectivity of the method. Finally, the sensing system was successfully used for OGT detection in blood samples with satisfied recovery. In summary, the label-free SPR platform for accurate detection of OGT in real samples is helpful to promote OGT serve as a biomarker for early clinical diagnosis of O-GlcNAc related diseases.

Gold nanoparticle (AuNP) modification shows great advantages in improving the antioxidant activity of nanoCeO2. However, the improved effect of AuNP modification becomes smaller and even results in the decrease of antioxidant ability due to severe aggregation with increasing nanomaterial concentration. Additionally, the effects of photo-properties of AuNPs on the antioxidant activity of nanoCeO2 have not been studied. In response to these problems, core-shell-shaped Au@CeO2 was synthesized which took Au nanorods (AuNRs) as carriers and had a layer of CeO2 NP coating. The antioxidant activity of Au@CeO2 was evaluated by the UV-vis method in the methyl violet-Fenton system. Results showed that AuNRs could improve the antioxidant activity of nanoCeO2 due to the increase in the amount of Ce3+ on the surface of nanoCeO2, and the enhancing effect remained across the whole experimental concentration range due to the good dispersibility of AuNRs. Additionally, a further increase in the antioxidant ability of Au@CeO2 was found with 5 min visible light irradiation, and continuous irradiation during a 25 min time reaction, which resulted in more obvious enhanced antioxidant ability. This phenomenon was attributed to the localized surface plasmon resonance of AuNRs triggered by photons which induced charge transfer from AuNRs to nanoCeO2, thus making the cyclic transformation between Ce3+ and Ce4+ easier.

Many nanomaterials have been reported to have enzyme-like activities and are considered as nanozymes. As a multifunctional nanozyme, nanoceria has received much attention due to the dual oxidation states of Ce3+/Ce4+ which facilitate redox reactions at the particle surface. Despite the advantages of nanozymes, their limited activity and lack of enzyme specificity are still problems to be resolved. DNA is used to modulate the oxidase activity of nanoceria because it has recently become an important molecule in bionanotechnology. However, the current research on the effect of DNA on the oxidase mimetic activity of nanoceria is contradictory. It has been discovered that nanoceria used in recent works are different, including in particle size, doping and concentration, and these differences may affect the interaction between DNA and nanoceria, and then affect the oxidase mimetic activity of nanoceria. Hence, it is important to clarify the factors that affect the interaction between DNA with nanoceria. In this work, the interactions between DNA and nanoceria with three different morphologies (nanoparticles, nanocubes, and nanorods) have been investigated. Experimental results show that DNA has different influences on the oxidase mimetic activity of nanoceria with different morphologies. The oxidase mimetic activity of CeO2 nanoparticles and nanocubes increased, but that of CeO2 nanorods decreased, after DNA modification. The mechanism of these experimental results has been explored, and it has been found that it is the interaction between cerium and the phosphate backbone of DNA that changes with the different morphologies, resulting in the varying effect of DNA on the oxidase mimetic activity of nanoceria. These results may provide a better understanding of the effect of DNA on the oxidase mimetic activity of nanoceria and promote the applications of nanoceria.

A novel approach is proposed for the simultaneous optimization of mobile phase pH and gradient steepness in RP-HPLC using artificial neural networks. By presetting the initial and final concentration of the organic solvent, a limited number of experiments with different gradient time and pH value of mobile phase are arranged in the two-dimensional space of mobile phase parameters. The retention behavior of each solute is modeled using an individual artificial neural network. An “early stopping” strategy is adopted to ensure the predicting capability of neural networks. The trained neural networks can be used to predict the retention time of solutes under arbitrary mobile phase conditions in the optimization region. Finally, the optimal separation conditions can be found according to a global resolution function. The effectiveness of this method is validated by optimization of separation conditions for amino acids derivatised by a new fluorescent reagent.

As a recently developed and powerful classification tool, probabilistic neural network was used to distinguish cancer patients from healthy persons according to the levels of nucleosides in human urine. Two datasets (containing 32 and 50 patterns, respectively) were investigated and the total consistency rate obtained was 100% for dataset 1 and 94% for dataset 2. To evaluate the performance of probabilistic neural network, linear discriminant analysis and learning vector quantization network were also applied to the classification problem. The results showed that the predictive ability of the probabilistic neural network is stronger than the others in this study. Moreover, the recognition rate for dataset 2 can achieve to 100% if combining these three methods together, which indicated the promising potential of clinical diagnosis by combining different methods.

A novel method for the optimization of pH value and composition of mobile phase in HPLC using artificial neural networks and uniform design is proposed. As the first step, seven initial experiments were arranged and run according to uniform design. Then the retention behavior of the solutes is modeled using back-propagation neural networks. A trial method is used to ensure the predicting capability of neural networks. Finally, the optimal separation conditions can be found according to a global resolution function. The effectiveness of this method is validated by optimization of separation conditions for both basic and acidic samples.

Nucleosides in human urine have been studied frequently as a possible biomedical marker for cancers, acquired immune deficiency syndrome (AIDS) and the whole-body turnover of RNAs. A capillary electrophoretic method that can quantitatively analyze urinary normal and modified nucleosides in less than 40 min with a good resolution and sufficient sensitivity has been developed. Twelve kinds of normal and modified nucleosides were determined in urine samples from 25 healthy persons and 25 cancer patients of 14 kinds of cancers. Artificial neural networks have been used as a powerful pattern recognition tool to distinguish cancer patients from healthy persons. The recognition rate for the training set reached to 100% and above 85% of the members in the predicting set were correctly classified. In addition, the neural network technique was compared with methods of the principal component analysis and the canonical discriminant analysis. The results demonstrate that the predictive ability of the artificial neural network is stronger than the others in this study.

A comprehensive two-dimensional liquid chromatographic separation system based on the combination of a CN column and an ODS column is developed for the separation of components in a traditional Chinese medicine (TCM) Rhizoma chuanxiong. Two columns are coupled by a two-position, eight-port valve equipped with two storage loops and controlled by a computer. The effluent is detected by both the diode array detector and atmospheric pressure chemical ionization (APCI) mass spectrometer. More than 52 components in the methanol extract of R. chuanxiong were resolved and 11 of them were preliminary identified according to their UV and mass spectra.