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Irritable bowel syndrome (IBS) is characterized by gastrointestinal dysmotility and visceral hyperalgesia, and the impaired brain–gut axis is accepted as a crucial cause for the onset of IBS. The objective of this study is to investigate the effects of the adaptive changes in the central neural system induced by stress on IBS-like syndromes in rats. Long-term water avoidance stress (WAS) was used to prepare IBS animals. The changes in neuronal excitation and GABA expression were shown by immunohistochemistry. The mRNA and protein expressions of neurotransmitters were detected with Quantitative reverse-transcription PCR (qRT-PCR) and Enzyme-linked immunosorbent assay (ELISA). The intestinal transit time, fecal moisture content, and abdominal withdrawal reflex scores of rats were recorded to monitor intestinal motility and visceral hyperalgesia. In the WAS-treated rats with enhanced intestinal motility and visceral hypersensitivity, more GABAergic projections were found in the paraventricular nucleus (PVN) of the hypothalamus, which inhibited the firing rate of neurons and decreased the expression of oxytocin. Exogenous oxytocin improved gut motility and decreased AWR scores. The inhibition of oxytocin by the adaptive GABAergic projection in the PVN might be an important mediator of IBS, which indicates a potential novel therapeutic target.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers and its dismal prognosis indicates the urgent need to elucidate the potential oncogenic mechanisms. SIRT7 is a classic NAD+-dependent deacetylase that stabilizes the transformed state of cancer cells. However, its functional roles in PDAC are still unclear. Here, we found that SIRT7 expression is upregulated and predicts poor prognosis in PDAC. Then we screened the new interacting proteins of SIRT7 by mass spectrometry and the results showed that SIRT7 can interact with O-GlcNAc transferase (OGT). O-GlcNAcylation stabilizes the SIRT7 protein by inhibiting its interaction with REGγ to prevent degradation, and hyper-O-GlcNAcylation in pancreatic cancer cells leads to hypoacetylation of H3K18 via SIRT7, which promotes transcriptional repression of several tumour suppressor genes. In addition, SIRT7 O-GlcNAcylation at the serine 136 residue (S136) is required to maintain its protein stability and deacetylation ability. In vivo and in vitro experiments showed that blocking SIRT7 O-GlcNAcylation at S136 attenuates tumour progression. Collectively, we demonstrate that O-GlcNAcylation is an important post-translational modification of SIRT7 in pancreatic cancer cells, and elucidating this mechanism of SIRT7 is expected to pave the way for the development of novel therapeutic methods in the future.

Soil contaminated by polycyclic aromatic hydrocarbons (PAHs) is a common problem in the world. Mechanochemical treatment is a promising technology for remediation of PAH-contaminated soil. This study investigated the feasibility of pyrene degradation with silica by mechanochemical remediation. The effects of ball milling time and rotation speed on the removal efficiency of pyrene in soil were also studied. When the milling time was 3 h and the rotation speed was 500 rpm, the removal efficiency of pyrene in soil was over 98%. The intermediate products detected by gas chromatography–mass spectrometry proved that the hydrogenation reaction and the destruction of benzene rings occurred in the milling process. Both graphite and amorphous carbon were detected by Raman spectra. The main degradation pathway and mechanism of pyrene by mechanochemical treatment should be the destruction of benzene rings caused by free radicals and further carbonization.

The removal of lead Pb (II) and cadmium Cd (II) from wastewater by using three different types of kaolin including natural kaolin, sodium hydroxide NaOH-modified kaolin, and NaOH-calcination-modified (combined modified) kaolin was studied. Textural properties of the three types of kaolins were characterized by scanning electron microscopy, fourier transform infrared spectroscopy, and specific surface area analysis. The effects of calcination temperature, contact time, adsorption temperature, pH, and kaolin dosage were investigated. Results showed that NaOH-calcination-modified kaolin performed best among the three kaolins in removing Pb (II) and Cd (II). Compared to NaOH-modified and natural kaolin, the shape of combined modified kaolin was irregular, and its surface was rough and loose with bigger pore volume. The adsorption capacity of Pb (II) and Cd (II) could reach the maximum of 161.84 and 108.13 mg g-1, respectively, under the following condition: initial concentration of heavy metals ions was 200 mg L-1, pH was 5.5, adsorption temperature was 25°C, contact time was 60 min, and NaOH-calcination-modified kaolin dosage was 1 g. Combined modified kaolin was also applied to remove heavy metal ions from actual industrial wastewater samples, and the results demonstrated that modified kaolin is a type of useful adsorbent for the removal of heavy metals from wastewater. Furthermore, the adsorption process of kaolin on Pb (II) and Cd (II) conformed to first and second-order kinetics equation, respectively.

Radiation resistance is a main obstacle for clinical treatment of lung squamous cell carcinoma (LUSC). Recent studies have demonstrated that long noncoding RNA (lncRNA) can participate in LUSC tumorigenesis and radiosensitivity. The current study explored the role and mechanism of lncRNA FOXD1-AS1 in mediating radioresistance of LUSC cells. Expression levels of FOXD1-AS1, miR-4801 and pumilio RNA binding family member 1 (PUM1) in LUSC cell lines were estimated by RT-qPCR. PUM1 protein expression in cells were quantified by western blotting. CCK-8 and colony formation assays were conducted to measure LUSC cell viability and proliferation, respectively. TUNEL assays were used to analyze LUSC cell apoptosis. Subcellular localization of FOXD1-AS1 was determined via subcellular fractionation assay. The regulatory relationship among FOXD1-AS1, miR-4801 and PUM1 was verified by RNA pulldown assay, luciferase reporter assay and RNA immunoprecipitation assay.