Polycyclic aromatic hydrocarbons exposure was associated with microRNA differential expression and neurotransmitter changes: a cross-sectional study in coal miners.

Exposure to polycyclic aromatic hydrocarbons (PAHs) may cause neurobehavioral changes. This study aimed to explore the underlying mechanism of PAH neurotoxicity in coal miners. Urinary PAH metabolites, neurotransmitters, and oxidative stress biomarkers of 652 coal miners were examined. Subjects were divided into high and low-exposure groups based on the median of total urinary PAH metabolites. Differentially expressed miRNAs were screened from 5 samples in the low-exposure group (≤ 4.88 µmol/mol Cr) and 5 samples in the high-exposure group (> 4.88 µmol/mol Cr) using microarray technology, followed by bioinformatics analysis of the potential molecular functions of miRNA target genes. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was used to validate differentially expressed miRNAs. Restricted cubic splines (RCS) were applied to assess the possible dose-response relationships. Compared to the low PAH exposure group, the high-exposure group had higher levels of 5-hydroxytryptamine (5-HT), epinephrine (E), and acetylcholine (ACh), and lower levels of acetylcholinesterase (AChE). 1-OHP had a dose-response relationship with malondialdehyde (MDA), dopamine (DA), 5-HT, and AChE (P for overall associations < 0.05). There were 19 differentially expressed microRNAs in microarray analysis, significantly enriched in the cell membrane, molecular binding to regulate transcription, and several signaling pathways such as PI3K-Akt. And in the validation stage, miR-885-5p, miR-20a-5p, and let-7i-3p showed differences in the low and high-exposure groups (P < 0.05). Changes in neurotransmitters and microRNA expression levels among the coal miners were associated with PAH exposure. Their biological functions are mainly related to the transcriptional regulation of nervous system diseases or signaling pathways of disorders. These findings provide new insights for future research of PAH neurotoxicity.

Abnormal night sleep duration and inappropriate sleep initiation time are associated with elevated anxiety symptoms in Chinese rural adults: the Henan Rural Cohort.

Sleep problems have been demonstrated to cause mental symptoms, such as anxiety. However, research on the association of the night sleep duration and sleep initiation time on anxiety symptoms in rural China is still lacking. The current study, therefore, explored the independent and combined association of the night sleep duration and sleep initiation time on anxiety symptoms. This study included 28, 054 participants from the Henan Rural Cohort. Sleep was measured using the Pittsburgh Sleep Quality Index (PSQI). Anxiety was assessed by the two-item Generalized Anxiety Disorder scale (GAD-2). Multivariable logistic regression models and restricted cubic spline with anxiety symptoms as a dependent variable were fitted. Among the participants in this study, 11, 209 (39.96%) were males, and 16,845 (60.04%) were females, 1574 (5.61%) had anxiety symptoms. Both shorter and longer night sleep duration were significantly related to elevated prevalence of anxiety symptoms. Extreme sleep initiation time was also significantly associated with elevated anxiety symptoms. Additionally, night sleep duration and sleep initiation time had a combined effect on the prevalent anxiety symptoms. In conclusion, there was a dose-response association of night sleep duration and sleep initiation time with anxiety among Chinese rural population. Moreover, they might jointly increase the odds of prevalent anxiety.

Polymer brushes on structural surfaces: a novel synergistic strategy for perfectly resisting algae settlement.

The current paper reports a novel model of a marine antibiofouling surface based on polymer brushes on a wrinkled silicone elastomer. Polymer brushes (POEGMA and PSPMA) were grafted via surface-initiated atom transfer radical polymerization (SI-ATRP). Successful grafting was verified with various characterization techniques including infrared spectroscopy, X-ray photoelectron spectroscopy and contact angle measurements. A series of laboratory static and dynamic bioassays as well as field immersion tests were carried out to systematically investigate the relationship between surface chemistry, surface topography and antifouling properties. The results indicated that the adhesion of marine organisms was strongly influenced by the surface chemistry composition and surface topography structure. The synergistic effect of the surface chemistry, surface topography and bulk properties of the substrates endowed the new marine coatings with excellent antifouling properties.

One-step modification of fabrics with bioinspired polydopamine@octadecylamine nanocapsules for robust and healable self-cleaning performance.

An in-situ polymerization to coat fabrics with polydopamine-encapsulated octadecylamine endows the fabrics with self-cleaning and self-healing abilities. The treated fabric exhibits self-healing after losing its hydrophobicity. It is durable against washing and mechanical abrasion without changing the hydrophobicity. Thanks to the versatile adhesive property of polydopamine, the approach is compatibile with a variety of substrates, such as fabrics, glass, sponge, paper, and polymeric materials.

Grafting zwitterionic polymer brushes via electrochemical surface-initiated atomic-transfer radical polymerization for anti-fouling applications.

Zwitterionic polymer brushes based on sulfobetaine vinylimidazole (pSBVI) were successfully grafted to silicon substrates by electrochemical surface-initiated atomic-transfer radical polymerization (e-SIATRP), and exhibited excellent anti-fouling activities because of the presence of the two bactericidal functional groups, imidazolium and sulfonate. Various characterization techniques, including atomic force microscopy, X-ray photoelectron spectroscopy and use of a quartz crystal microbalance, were employed to characterize the polymer brush-modified silicon substrates. Subsequently, the anti-bacterial and anti-biofouling activities of the polymer brush substrates were evaluated. The experimental results showed that the pSBVI effectively resisted the adhesion of Nannochloropsis maritima and showed good anti-bacterial activity against Escherichia coli. In addition, in comparison with poly(vinylimidazole) brush-modified substrates and the bare substrate, the pSBVI-based materials also exhibited excellent anti-adsorption performance against both bovine serum albumin and lysozyme.

Fusion and alloying of (bi)metallic nanocrystals onto TiO2 nanowires in the presence of surface grafted polymer brushes.

In present paper, the fusion of metal nanocrystals on TiO2 nanowires is studied and utilized to synthesize bimetallic nanoparticles on nanowires. Cationic polydimethyl aminoethyl methacrylate (PDMAEMA) brushes are grafted onto TiO2 nanowires, and palladium nanocrystals are produced by polymer brush-bound PdCl(4)(2-) and subsequent in situ reduction with NaBH4 in high density and low polydispersity. It is found that Pd nanocrystals of 2-3 nm starts to fuse even at 100 °C, but are apparently obstructed by the polymer brush matrix. Nanocrystal fusion speeds up instantly after polymer decomposition degradation at temperatures above 300 °C. By taking advantage of the polymer brush technique successive, templated uploading of different nanoparticles and fusion, Pd-Au bimetallic nanoparticles or alloys are formed on TiO2 nanowires. The results provide a novel method towards TiO2 nanowire supported (bi)metallic nanoparticles and have hinted at practical uses for elucidating the catalytic behavior of the composites.

Reversible hydration and dehydration of polyanionic brushes bearing carboxylate, phosphate and sulfonate side groups: a comparative AFM study.

The present work reports on a systematic study of the swelling/collapse transition of three anionic polymer brushes bearing carboxylate, phosphate and sulfonate side groups via AFM measurement. Time scale of conformation change process can be approximately evaluated directly. All the three brushes in their sodium salt forms stretch away from the surface in pure water, as a result of charge repulsion and uptake of water. The collapse of weak brushes has two ways: normal charge screening and precipitation (strong ion pairing), depending on the types of cations that have different coordination capabilities with anionic groups. Alkali metal ions can make brushes shrink only at relatively high concentrations following a gradually increased charge screening mechanism. The brushes collapsed in this way can be restored by simply flushing with water. However, multivalent cations can irreversibly collapse brushes more easily even under very low concentrations (<10(-3) mol L(-1)). The brushes cannot be restored with simple water rinsing even for strong sulfonate containing brushes. In this case, recovery can be achieved by ion exchange in concentrated salt solution, which facilitates transit from strong ion pairing to less strong charge screening and then flushing with water. Alternatively, the multivalent ion can be extracted with chelating reagent of low concentration (10 mM EDTA). As the chelating agent doesn't affect the conformation of brushes, the brushes are one-step recovered directly, much more efficient than with high concentration electrolyte which usually requires extra water rinsing to remove excess salt inside brushes. The interaction between anions in the brushes and metal ions represents a model system to profoundly understand the mechanism of bio-mimic motions and how muscle works. In this regard, the present study provides useful information for the development of polyelectrolyte brushes based ion sensor and ion powered nanoactuators.

Probing the responsive behavior of polyelectrolyte brushes using electrochemical impedance spectroscopy.

Cyclic voltammetry and impedance spectroscopy were employed to probe the responsive properties of polyelectrolyte brushes. Poly[(dimethylamino)ethyl methacrylate] (PDMAEMA) brushes over 100 nm thick on gold substrates were synthesized via surface-initiated atom-transfer radical polymerization and quaternized with methane iodide to obtain cationic brushes (Q-PDMAEMA). Q-PDMAEMA brushes respond to electrolytes by exhibiting swollen and collapsed states. Swollen brushes allow good permeability of electroactive probes, while collapsed states block electron transport. Electrolytes have different impacts on the electrochemical properties of Q-PDMAEMA. Some salts (NaNO3) cause brush collapse due to charge screening, while others such as those with more hydrophobic anions (ClO4-, PF6-, and Tf2N-) induce brush collapse because of solubility changes. The collapsed brushes exhibit intrinsically different resistance as probed with impedance. Charged screened brushes retain good permeability to electroactive probes. Strongly coordinating hydrophobic anions lead to insoluble brushes, resulting in a high resistance. These results show that electrochemical impedance spectroscopy is a powerful technique to probe the properties and structure of polyelectrolyte brushes.