A Homeodomain-Containing Transcriptional Factor PoHtf1 Regulated the Development and Cellulase Expression in Penicillium oxalicum

Homeodomain-containing transcription factors (Htfs) play important roles in animals, fungi, and plants during some developmental processes. Here, a homeodomain-containing transcription factor PoHtf1 was functionally characterized in the cellulase-producing fungi Penicillium oxalicum 114-2. PoHtf1 was shown to participate in colony growth and conidiation through regulating the expression of its downstream transcription factor BrlA, the key regulator of conidiation in P. oxalicum 114-2. Additionally, PoHtf1 inhibited the expression of the major cellulase genes by coordinated regulation of cellulolytic regulators CreA, AmyR, ClrB, and XlnR. Furthermore, transcriptome analysis showed that PoHtf1 participated in the secondary metabolism including the pathway synthesizing conidial yellow pigment. These data show that PoHtf1 mediates the complex transcriptional-regulatory network cascade between developmental processes and cellulolytic gene expression in P. oxalicum 114-2. Our results should assist the development of strategies for the metabolic engineering of mutants for applications in the enzymatic hydrolysis for biochemical production

The research on FBW7 gene enhances antitumor effect of paclitaxel on pancreatic cancer through GSDME-mediated pyroptosis

Background and purpose: Pancreatic cancer is a highly malignant disease. Most patients are in advanced stage upon diagnosis. Systemic chemotherapy is an important treatment method, but the chemotherapy drug resistance to tumors brings many problems to clinical treatment. As a commonly used chemotherapy drug, paclitaxel can induce apoptosis in tumor cells. The FBW7 gene is a tumor suppressor gene, and the loss of its function can lead to tumor occurrence and progression. Research has shown that it has the effect of promoting tumor cell apoptosis and inhibiting tumor proliferation. In addition, this gene has been proven to promote apoptosis and ferroptosis, which increase the effect of chemotherapy drugs. Pyroptosis is a programmed cell death mode mediated by gasdermin (GSDM) protein, and this cell death is often accompanied by inflammatory reactions. This study aimed to investigate whether FBW7 gene can promote the anti-tumor effect of paclitaxel by increasing pyroptosis. Methods: A PANC-1 cell line overexpressing FBW7 was constructed using lentivirus transfection. The correlation between FBW7 and GSDME gene expressions was detected by immunohistochemistry in clinical samples, and the expression levels of mRNA and protein were detected by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) and Western blot. We observed the morphological changes of cells treated with paclitaxel under light microscopy. Cell counting kit-8 (CCK-8) was used to detect the effect of paclitaxel on cell viability, and flow cytometry and lactate dehydrogenase (LDH) release assay were performed to detect the effect of paclitaxel on cell death. Western blot was used to detect caspase-3 and GSDME activation after paclitaxel treatment. Results: RTFQ-PCR and Western blot experiments showed that overexpression of FBW7 gene increased the expression of GSDME. Immunohistochemical staining of pathological sections of clinical patients also showed that the expressions of FBW7 and GSDME genes was positively correlated in vivo. Flow cytometry and LDH release experiments showed that the level of cell death in pancreatic cancer cell line PANC-1 overexpressing FBW7 was significantly increased compared with its empty vector (EV) cells after being treated with paclitaxel. Under light microscopy, it was observed that the number of cells with pyroptosis was significantly higher in PANC-1 cell lines overexpressing FBW7 than in EV cells. The CCK-8 experiment results showed that the cell viability was significantly lower in FBW7 overexpressed cell lines than in EV cells after paclitaxel treatment. Western blot experiment results showed that after pancreatic cancer cell line PANC-1 was treated with paclitaxel, the protein expressions of active-caspase-3 and GSDME-NT in FBW7 overexpression cell lines increased, which proved that they had more obvious activation, indicating that the FBW7 gene can increase the sensitivity of PANC-1 cells to paclitaxel through caspase-3/GSDME signaling pathway induced cell pyroptosis. Conclusion: FBW7 can increase the sensitivity of pancreatic cancer cells to paclitaxel by increasing the expression of GSDME, which is realized through caspase-3/GSDME pathway

miR-122-5p Inhibits the Proliferation, Invasion and Growth of Bile Duct Carcinoma Cells by Targeting ALDOA

Background/Aims: Bile duct cancer, although not among the most common tumors, still accounts for more and more worldwide deaths each year. By attempting to verify an overexpression of ALDOA in cholangiocarcinoma tissues and cells and explore the underlying molecular mechanism regulated by miR-122-5p, this study was designed to provide a potential molecular target in bile duct cancer treatment. Methods: Western blot and immunohistochemistry were performed to detect the ALDOA protein level in duct carcinoma tissues. The transfection efficiency was confirmed by western blot and/or RT-qPCR assay. The proliferation of bile duct carcinoma cells was determined by MTT and colony formation assay. The invasion ability of bile duct carcinoma cells was evaluated with Transwell invasion assay. Flow cytometry detected cell apoptosis of bile duct carcinoma cells. The miRNAs which modulate ALDOA were filtrated from bioinformatics software and clinical specimens. The target relationship was confirmed by dual luciferase reporter assay. Furthermore, a xenograft model was completed to verify the impact of miRNA on inhibition growth of bile duct carcinoma cells. Results: ALDOA was found up-regulated in bile duct carcinoma tissues and cells. Knockdown of ALDOA promoted the apoptosis of cells and inhibited the proliferation and invasion of bile duct carcinoma cells. Bioinformatics and clinical specimens indicated the negative correlation and targeted regulation between miR-122-5p and ALDOA. By down-regulating ALDOA, overexpression of miR-122-5p appeared to promote cell apoptosis and significantly inhibit cell proliferation, invasion in vitro and suppress the tumor growth in vivo. Conclusion: miR-122-5p inhibited proliferation and invasion of bile duct carcinoma cells and promoted cell apoptosis by targeting ALDOA expression

Risks to human and animal health related to the presence of deoxynivalenol and its acetylated and modified forms in food and feed

Deoxynivalenol (DON) is a mycotoxin primarily produced by Fusarium fungi, occurring predominantly in cereal grains. Following the request of the European Commission, the CONTAM Panel assessed the risk to animal and human health related to DON, 3-acetyl-DON (3-Ac-DON), 15-acetyl-DON (15-Ac-DON) and DON-3-glucoside in food and feed. A total of 27,537, 13,892, 7,270 and 2,266 analytical data for DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside, respectively, in food, feed and unprocessed grains collected from 2007 to 2014 were used. For human exposure, grains and grain-based products were main sources, whereas in farm and companion animals, cereal grains, cereal by-products and forage maize contributed most. DON is rapidly absorbed, distributed, and excreted. Since 3-Ac-DON and 15-Ac-DON are largely deacetylated and DON-3-glucoside cleaved in the intestines the same toxic effects as DON can be expected. The TDI of 1 μg/kg bw per day, that was established for DON based on reduced body weight gain in mice, was therefore used as a group-TDI for the sum of DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside. In order to assess acute human health risk, epidemiological data from mycotoxicoses were assessed and a group-ARfD of 8 μg/kg bw per eating occasion was calculated. Estimates of acute dietary exposures were below this dose and did not raise a health concern in humans. The estimated mean chronic dietary exposure was above the group-TDI in infants, toddlers and other children, and at high exposure also in adolescents and adults, indicating a potential health concern. Based on estimated mean dietary concentrations in ruminants, poultry, rabbits, dogs and cats, most farmed fish species and horses, adverse effects are not expected. At the high dietary concentrations, there is a potential risk for chronic adverse effects in pigs and fish and for acute adverse effects in cats and farmed mink

Curing of epoxy resin by UV-light triggered descending frontal polymerization

221 type alicyclic epoxy resin was cured by UV-light initiated descending frontal polymerization. The effect of amount of photo/thermal initiator, pre-heating temperature on the frontal velocity Vf and frontal initiating time ti was investigated. The structure and thermal properties of the cured products were characterized via Fourier transform infrared spectroscopy(FTIR), thermogravimetric analysis(TG) and differential scanning calorimetry(DSC). The results show that frontal velocity Vf increase with increasing of concentration of photo/thermal initiator or preheating temperature, while frontal initiating time decrease. Analysis of the FTIR spectrum indicates that the products were obtained uniformly. TG and DSC results reveal that the products exhibit good thermal stability

Limonin ameliorates indomethacin‐induced intestinal damage and ulcers through Nrf2/ARE pathway

Abstract Background Nonsteroidal anti‐inflammatory drugs (NSAIDs) can cause intestinal damage and ulcers and the incidence is increasing. Limonin plays an important role in the regulation of inflammatory diseases, but it has not been reported in the treatment of intestinal injury and ulcers. Methods Indomethacin (INDO) induced intestinal injury and ulcer model in rats. The indexes related to intestinal injury were detected. Western blot and molecular docking techniques were used to detect the docking between Limonin and Nrf2. Next, ML385, an inhibitor of Nrf2/ARE signaling pathway, was applied to treat intestinal epithelial IEC‐6 cells induced by INDO. And CCK8, Western blot, TUNEL, ELISA, DCFH‐DA assay, kits, and immunofluorescence were conducted to detect cell activity, apoptosis, inflammatory response, oxidative stress, and tight junction again. Results INDO can significantly induce intestinal ulcerative lesions in rats. Limonin could improve intestinal ulcerative lesions induced by INDO in rats. Limonin could reduce INDO‐induced inflammatory response and oxidative stress in the small intestine of rats, and improve the intestinal barrier dysfunction induced by INDO. Limonin could dock with Nrf2 structure and activate Nrf2/ARE signaling pathway. ML385 could reverse the protective effect of Limonin against INDO‐induced cell damage. Conclusion Limonin ameliorates INDO‐induced intestinal damage and ulcers through Nrf2/ARE pathway

The antimicrobial effects and mechanism of ε-poly-lysine against Staphylococcus aureus

Abstract Background As a natural antibacterial cationic peptide, ε-poly-l-lysine (ε-PL) is applied as a food preservative. However, the mechanism of ε-PL against Staphylococcus aureus (S. aureus) has not been elucidated. Especially, its antimicrobial mechanism at the metabolomics has not been yet thoroughly described. Results This work aimed at clarifying the antibacterial activity and mechanism of ε-PL against S. aureus. Effects of ε-PL with different concentration on cell morphology, cell wall, and membrane integrity were investigated. Furthermore, the effect of ε-PL on metabolite properties of S. aureus was also studied. The results revealed that ε-PL disrupted the cell wall and membrane integrity of treated cells. ε-PL induced the structural change of peptidoglycan in cell wall, causing cell wall more fragile. Meanwhile, the permeability of the S. aureus cell membrane was increased by ε-PL. More importantly, ε-PL with different concentration could cause different effects on metabolic pathways of S. aureus. ε-PL with high concentration could directly restrain the central carbon metabolism. However, ε-PL with low concentration could only inhibit the glycolytic pathway. Conclusion These results showed that the antimicrobial mechanism of ε-PL against S. aureus was a synergistic action

Enzymes@ZIF-8 Nanocomposites with Protection Nanocoating: Stability and Acid-Resistant Evaluation

Zeolitic imidazole framework-8 (ZIF-8) with tunable pore sizes and high surface areas have recently emerged as a promising support for immobilizing enzymes. However, the instability in the aqueous acidic environment and difficulty of recovery has limited their practical applications in some cases. In this study, catalase/ZIF-8 composites with a protective nanocoating were prepared by the controlled self-assembly of silanes or coordination complexes (tannic acid (TA) and Fe3+). The properties of the catalase (CAT)/ZIF-8 composites with a protective nanocoating were also determined. The recovered activity of CAT/ZIF-8 and CAT/ZIF-8 with protective nanocoating was 70% and 65%, respectively. Compared with the conventional CAT/ZIF-8 composites, CAT/ZIF-8 with protective nanocoating exhibited excellent acid resistance. For example, after treatment for 60 min in phosphate buffer solution (pH 3.0), CAT/ZIF-8 composites only maintained 20% of their initial activity (about 12 U/mg). However, CAT/ZIF-8 with a protective nanocoating could still retain about 50% of its initial activity (about 10 U/mg). Meanwhile, the thermostability and storage stability of the CAT/ZIF-8 composites was enhanced significantly due to the presence of nanocoating compared with conventional CAT/ZIF-8. More importantly, the CAT/ZIF-8 with a protective nanocoating retained 40% of its initial activity after 7 cycles, whereas CAT/ZIF-8 only retained 8% of the initial activity. The approach in this study could be an efficient strategy to prepare enzyme/ZIF-8 composites with both high acid resistance and excellent recyclability

A Highly Efficient Fluorescent Sensor Based on AIEgen for Detection of Nitrophenolic Explosives

The detection of nitrophenolic explosives is important in counterterrorism and environmental protection, but it is still a challenge to identify the nitroaromatic compounds among those with a similar structure. Herein, a simple tetraphenylethene (TPE) derivative with aggregation-induced emission (AIE) characteristics was synthesized and used as a fluorescent sensor for the detection of nitrophenolic explosives (2, 4, 6-trinitrophenol, TNP and 2, 4-dinitrophenol, DNP) in water solution and in a solid state with a high selectivity. Meanwhile, it was found that only hydroxyl containing nitrophenolic explosives caused obvious fluorescence quenching. The sensing mechanism was investigated by using fluorescence titration and 1H NMR spectra. This simple AIE-active probe can potentially be applied to the construction of portable detection devices for explosives