[Interventional effect of bicyclol on isoniazid-induced liver injury in rats and the expression of glucose-regulated protein 78, and growth arrest and DNA-damage-inducible gene 153]

Objective: To investigate the interventional effect of bicyclol on isoniazid-induced liver injury in rats and the expression of endoplasmic reticulum stress (ERS) protein, glucose regulatory protein 78 (GRP78), and growth arrest and DNA-damage-inducible gene 153(CHOP). Methods: Eighty Wistar rats were randomly divided into control group (8 rats) and model group (72 rats). After 10 days of intragastric administration of isoniazid, the model group rats were randomly divided into treatment group (A), natural recovery group (B), etiological persistence group (C) and etiological persistence plus treatment group (D). Sixteen rats from each group were sacrificed after 1 and 2 weeks of intervention with different methods. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected. Liver pathological morphology was observed. Apoptotic cells were detected by TUNEL assay. ERS protein expression was detected by Western blot. A t-test or randomized block analysis of variance, K-S test and Levene's test were used to analyze the normality and homogeneity of variance. Kruskal-Wallis rank sum test was used for data that did not suit the conditions of t-test and variance analysis. Results: ALT and AST were elevated in the model group, and liver pathological examination showed liver tissue damage. Apoptotic index was higher than control group (7.13% ± 1.55% vs. 0.75% ± 0.71%, Z = -3.411, P < 0.01), and the expression value of ERS protein in model group was significantly higher than control group (GRP78: 1.16 ± 0.30 vs. 0.23 ± 0.05, t = -6.008, P < 0.01; CHOP: 0.98±0.23 vs. 0.20 ± 0.10, t = -6.378, P < 0.01). Serum enzymes, apoptotic index and ERS protein expressions of rats were decreased after treatment with bicyclol, and the pathological damage was eased. Rats in natural recovery group recovered less than the treatment group. Conclusion: Isoniazid-induced liver injury is associated to ERS-related excessive apoptosis and the therapeutic effect of bicyclol on drug-induced liver injury may minimize ERS-induced apoptosis.

Significant colour tuning via energy transfer in Eu2+ solely doped La2.5Ca1.5Si12O4.5N16.5

A large shift of the emission colour from blue-green to orange is observed in La_2.5Ca_1.5−yEu_ySi₁₂O_4.5N_16.5 phosphors, due to increased energy transfer between Eu²⁺ ions at different crystal sites.

Field investigation of advanced oxidation of secondary effluent from municipal wastewater treatment plant

Successful treatment of the secondary effluent ensures its safe disposal and water reclamation for water reuse. To understand the effect of ultraviolet (UV) irradiation in combination with hydrogen peroxide (H(2)O(2)) on secondary effluent under field conditions, an advanced oxidation system, UV+H(2)O(2), was installed and fed with the effluent at 1.0, 1.5 and 2.0 m(3) h(- 1) over a period of 6 months. The electrical energy density for the UV reactor was varied between 0.5 and 5.2 kWh m(-3) and H(2)O(2) added at concentrations of 0, 13 or 26 mg L(-1). The feed and product water samples were taken periodically and analyzed for biological (heterotrophic plate count-HPC, total and fecal coliform-TC and FC) and chemical (NH(4)(+)-N, NO(3)(-)-N, NO(2)(-)-N and total organic carbon-TOC) parameters. For the treatment of UV+26 mg L(- 1) H(2)O(2), flow rates of 1.0, 1.5 and 2.0 m(3) h(- 1) resulted in > 4-log removal of HPC with a maximum survivor of 20 CFU mL(-1) and > 4 log reduction of FC with a survivor of 8 CFU (100 mL)(- 1). The electrical energy density of 1.5 kWh m(-3) was optimum for the inactivation. The NO(2)(-)-N concentrations of the product water were 0.09-0.42 mg L(- 1) compared with 0.04-0.09 mg L(- 1)in the feed. With or without H(2)O(2) addition, NO(2)(-)-N concentration increased with increases in UV electrical energy density. The highest increase in NO(2)(-)-N was associated with the maximum energy density of 5.2 kWh m(-3). Increase in H(2)O(2) dose reduced NO(3)(-)-N concentration by 2.0 to 5.7%. The overall results showed that the advanced oxidation technology prepared the effluent for safe disposal and/or for water reclamation for reuse.

Permeate flux optimisation of a pilot microfiltration plant for cost-effectiveness of water reclamation for reuse

A pilot plant was constructed with eight elements of an Asahi microfiltration (MF) membrane-a total filtration surface area of 56 m2. Performance of the plant was examined in preparation of a secondary sewage effluent without coagulant for reverse osmosis membrane treatment. Production at different permeate flux was tested for evaluation of the changes in transmembrane pressure (TMP) and specific permeate flux (SPF) with time. Clean-in-place (CIP) was conducted when TMP reached a value about 2 atm after each test. For permeate flux of 48, 55, 61 and 66 L m-2 h-1, the ceiling TMP was reached after filtration for approximately 420, 200, 225, and 195 h, respectively. The corresponding cumulative permeate volumes were 1130, 620, 765, 720 m3 before a CIP was necessary. The SPF decreased quickly with increases in permeate flux and the corresponding half-SPF times were 147, 89, 75 and 39 h for the respective flux studied. The membrane fouling tolerance was greater at a lower than at a higher flux. Analysis of the performance data suggests that run of the MF plant at higher permeate flux with more frequent and quick CIP might produce more water. The optimal filtration durations were found to be 12, 8, 7 and 3 days for permeate flux of 48, 55, 61 and 66 L m-2 h-1, respectively. Prolonged filtration after the optimal interval without CIP may not maximise the economical benefit.

Destruction of organic pollutants in reusable wastewater using advanced oxidation technology

This work studied the destruction of various M-EDTA complexes and trace organic pollutants in treated reusable wastewater under advanced oxidation using UV irradiation and ozonation. Effect of dosage of hydrogen peroxide and acidity of reaction matrices on oxidation efficiencies were investigated. The rate constant of mineralization presents a decreasing trend as Fe(III)-EDTA > Fe(II)-EDTA > Al(III)-EDTA > Pb(II)-EDTA > Na(I)-EDTA > Zn(II)-EDTA > Cu(II)-EDTA. The mineralization efficiencies using ozone alone are 15%, 40% and 15% for the water samples after reverse osmosis (RO), microfiltration (MF) and superfiltration (SF) processes, respectively. The presence of hydrogen peroxide in photochemical reaction matrixes can effectively enhance the mineralization of organic carbon species. When 150 mg l(-1) of H2O2 was added in the effluents, the mineralization markedly increased to 80%, 92% and 89%, respectively.

Destruction of model organic pollutants in water using ozone, UV and their combination (Part I)

The experimental results showed that ozone (O3) oxidation is an effective means to destroy phenolic organic pollutants present in water. High removal efficiencies can be readily achieved for most of the model compounds fortified in aqueous matrices within a reasonable time frame. This study also included the oxidation of phenolic compounds using ozone in combination with ultraviolet (UV) irradiation. The extent of mineralization measured in terms of the losses in total organic carbon is promoted by the joint action of ozone and UV in comparison with using ozone alone.