Continuous and complete conversion of high concentration p-nitrophenol in a flow-through membrane reactor

Here, we report on a green and effective method for the continuous and complete conversion of high concentrations of p-nitrophenol (PNP) using a flow-through membrane reactor and less NaBH4. The catalytic membrane was successfully fabricated by loading Pd nanoparticles onto the surface of a branched TiO2 nanorod-functionalized ceramic membrane. The modification with branched TiO2 nanorods can significantly improve the loading amount of Pd nanoparticles onto ceramic membranes, resulting in enhanced catalytic performance. With 6 mg of Pd, 93 L m−2 hr−1 of flux density and 8.04 cm2 of membrane surface area in the flow-through membrane reactor, PNP at a concentration of 4,000 ppm can be converted to high-value p-aminophenol using less NaBH4 (using a molar ratio of NaBH4:PNP of 9.6) within 24 s at 30°C. More importantly, the conversion can be continuously and stably performed for 240 min

Evaluation of the toxicity of fluorine in Antarctic krill on soft tissues of Wistar rats

Antarctic krill are a potential food source for humans and animals, but krill are known to contain high levels of fluorine (F). In this study, we investigated the toxicity of F in Antarctic krill using Wistar rats. There were three experimental groups: The control group were fed a basal diet, the krill treatment group were fed the same basal diet mixed with krill powder (150 mg∙kg-1 F), and the sodium fluoride (NaF) treatment group were fed the basal diet with added NaF (150 mg∙kg-1 F). General toxicity indicators including body weight and food intake were measured during the experiment. After three months the rats were dissected and tissue samples were collected from the liver, kidney, spleen, brain, and testis. Morphological changes in the cells of these tissues were assessed using HE staining. There were no significant differences in the body weight, the food intake, or the viscera coefficients among the three groups. In both treatment groups some pathological changes were observed in all soft tissue samples except the testis, although there were fewer and less severe pathological changes in the krill treatment group than in the NaF treatment group. The results showed that the toxicity of F in Antarctic krill was lower than for an equivalent amount of F in NaF, but it was still toxic to rats consuming large quantities of krill. The findings of this study highlight the need for further investigation into potential F toxicity if krill is to be used for human consumption

CERKL regulates autophagy via the NAD-dependent deacetylase SIRT1

<p>Macroautophagy/autophagy is an important intracellular mechanism for the maintenance of cellular homeostasis. Here we show that the <i>CERKL</i> (ceramide kinase like) gene, a retinal degeneration (RD) pathogenic gene, plays a critical role in regulating autophagy by stabilizing SIRT1. <i>In vitro</i> and <i>in vivo</i>, suppressing CERKL results in impaired autophagy. SIRT1 is one of the main regulators of acetylation/deacetylation in autophagy. In CERKL-depleted retinas and cells, SIRT1 is downregulated. ATG5 and ATG7, 2 essential components of autophagy, show a higher degree of acetylation in CERKL-depleted cells. Overexpression of SIRT1 rescues autophagy in CERKL-depleted cells, whereas CERKL loses its function of regulating autophagy in SIRT1-depleted cells, and overexpression of CERKL upregulates SIRT1. Finally, we show that CERKL directly interacts with SIRT1, and may regulate its phosphorylation at Ser27 to stabilize SIRT1. These results show that CERKL is an important regulator of autophagy and it plays this role by stabilizing the deacetylase SIRT1.</p

Evaluation of the biological toxicity of fluorine in Antarctic krill

Antarctic krill is a potentially nutritious food source for humans, but fluorine (F) toxicity is a matter of concern. To evaluate the toxicity of F in Antarctic krill, 30 Wistar rats were divided into three groups with different dietary regimens: a control group, a krill treatment group (150 mg·kg−1 F), and a sodium fluoride (NaF) treatment group (150 mg·kg−1 F). After three months, F concentrations in feces, plasma, and bone were determined, and the degree of dental and skeletal fluorosis was assessed. The F concentrations in plasma and bone from the krill treatment group were 0.167 0±0.020 4 mg.L−1 and 2 709.8±301.9 mg·kg−1, respectively, compared with 0.043 8±0.005 5 mg·L−1 and 442.4±60.7 mg·kg−1, respectively, in samples from the control group. Concentrations of F in plasma and bone in the krill treatment group were higher than in the control group, but lower than in the NaF treatment group. The degree of dental fluorosis in the krill treatment group was moderate, compared with severe in the NaF treatment group and normal in the control group. The degree of skeletal fluorosis did not change significantly in any group. These results showed that the toxicity of F in Antarctic krill was lower than for an equivalent concentration of F in NaF, but it was toxic for rats consuming krill in large quantities. To conclude, we discuss possible reasons for the reduced toxicity of F in Antarctic krill. The present study provides a direct toxicological reference for the consideration of Antarctic krill for human consumption

Construction and Synergistic Effect of Recombinant Yeast Co-expressing Pig IL-2/4/6 on Immunity of Piglets to PRRS Vaccination

AbstractIn order to develop cost-effective immunomodulator, the recombinant Pichia pastoris were firstly constructed to co-express porcine IL-2/4/6 genes, and then fermented to feed 45-days Tibetan piglets at different doses to evaluate its effects on immunity of piglets to PRRS vaccination, which simultaneously received intramuscular injection of inactivated PRRS vaccine. The results were found that the leukocytes, IgG and specific antibody to PRRSV, Th and Tc cells increased significantly in the blood of treated piglets in comparison with those of the control (P<0.05); the mRNA expression of TLRs (TLR-2, 3, 4, 7, 9), IFN-γ, IL-2, IL-4, IL-6, IL-7, IL-12 and IL-15 genes were elevated significantly in the immune cells from the blood of treated piglets (P<0.05). Moreover, the growth of the treated piglets also markedly improved whose average net weight gain was significantly higher than the control on 58 days post inoculation (P<0.05). These results suggest that the recombinant yeast can effectively enhance the systematic innate and adaptive immunity of piglets as well as promote the growth of piglet, which could be further developed as cost-effective promising immunomodulator to improve the control of pig PRRS disease