Search

A novel salt-tolerant strain DUT_AHX, which was capable of utilizing nitrobenzene (NB) as the sole carbon source, was isolated from NB-contaminated soil. Furthermore, it was identified as Streptomyces albidoflavus on the basis of physiological and biochemical tests and 16S ribosomal DNA (rDNA) sequence analysis. It can grow in the presence of NaCl up to 12% (w/v) or NB up to 900 mg/l in mineral salts basal (MSB) medium. The exogenously added osmoprotectants such as glycin, glutamic acid, proline, betaine and ectoine can improve growth of strain DUT_AHX in the presence of 10% (w/v) NaCl. NB-grown cells of strain DUT_AHX in modified MSB medium can degrade NB with the concomitant release of ammonia. Moreover, crude extracts of NB-grown strain DUT_AHX mainly contained 2-aminophenol 1,6-dioxygenase activity. These indicate that NB degradation by strain DUT_AHX might involve a partial reductive pathway. The proteins induced by salinity stress or NB were analyzed by native-gradient polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS)-PAGE. In NB-induced proteins de novo, 141 kDa protein on the nativegradient PAGE gel was excised and electroeluted. Furthermore, enzyme tests exhibit the 2-aminophenol 1,6-dioxygenase activity of purified 141 kDa protein is 11-fold that of the cell-free extracts. The exploitation of strain DUT_AHX in salinity stress will be a remarkable improvement in NB bioremediation and wastewater treatment in high salinity. [ABSTRACT FROM AUTHOR]

The accelerating effect of quinones has been studied in the bio-decolorization processes, but there are no literatures about the incorporation biotreatment technology of the bromoamine acid (BA) wastewater and azo dyes wastewaters under high-salt conditions (NaCl, 15%, w/w). Here we described the BA wastewater as a redox mediator in the biodecolorization of azo dye wastewaters. Decolorization of azo dyes was carried out experimentally using the salt-tolerant bacteria under the BA wastewater and high-salt conditions. The BA wastewater used as a redox mediator was able to increase the decolorization rate of wastewater containing azo dyes. The effects of various operating conditions such as dissolved oxygen, temperature, and pH on microbial decolorization were investigated experimentally. At the same time, BA was tested to assess the effects on the change of the Oxidation-Reduction Potential (ORP) values during the decolorization processes. The experiments explored a great improvement of the redox mediator application and the new bio-treatment concept. [ABSTRACT FROM AUTHOR]

Halomonas sp strain GTW was newly isolated from coastal sediments contaminated by chemical wastewater and was identified to be a member of the genus Halomonas by 16S rDNA sequence analysis and physical and biochemical tests. The optimal decolorization conditions were as follows: temperature 30°C, pH 6.5.0-8.5, NaCl 10-20% (w/v) and the optimal carbon source was yeast exact. The results of experiments demonstrated that the bacteria could decolorize different azo dyes under high salt concentration conditions, and the decolorization rate of five tested azo dyes could be above 90% in 24 h. The exploitation of the salt-tolerant bacteria in the bio-treatment system would be a great improvement of conventional biological treatment systems and the bio-treatment concept. [ABSTRACT FROM AUTHOR]

Some experiments were conducted to study some electrochemical factors affecting the bacterial reduction (cleavage) of azo dyes, knowledge of which will be useful in the wastewater treatments of azo dyes. A common mixed culture was used as a test organism and the reductions of Acid Yellow 4, 11, 17 and Acid Yellow BIS were studied. It was found that the azo dyes were reduced at different rates, which could be correlated with the reduction potential of the azo compounds in cyclic voltammetric experiments. Acid Yellow BIS (Er - 616.75 mV) was reduced at the highest rate of 0.0284 mol g dry cell weight-1 h-1, Acid Yellow 11 (Er - 593.25 mV) at 0.0245 mol g dry cell weight-1 h-1 and Acid Yellow 4 (Er - 513 mV) at 0.0178 mol g dry cell weight-1 h-1. At the same time, the decolourization rate of Acid Yellow 17 (Er - 627.5 mV) was 0.0238 mol g dry cell weight-1 h-1, which was affected by the nature of chlorine substituent. Reduction of these azo dyes did not occur under aeration conditions. These studies with a common mixed culture indicate that the reduction of azo dyes may be influenced by the chemical nature of the azo compound. The reduction potential is a preliminary tool to predict the decolourization capacity of oxidative and reductive biocatalysts. [ABSTRACT FROM AUTHOR]

Objective: Endoplasmic reticulum (ER) stress causes an adaptive response initiated by protein kinase RNA-like ER kinase (PERK), Ire1 and ATF6. It has been reported that these upstream regulators induce microRNAs. The current study was designed to find a novel microRNA that mediates ER stress components and finally contributes to cell fate decision. Materials and Methods: In this experimental study, miR-706 levels were checked under different conditions of ER stress induced by Thapsigargin, Tunicamycin or low glucose media. PERK and ATF4 were knocked-down by administration of lentivirus-mediated short hairpin RNA to explore the effect of ER stress related proteins on miR-706 expression. The effect of miR-706 on caspase activity and apoptosis inhibitor 1 (CAAP1) levels were examined by using mimic-miR-706. The role of CAAP1 in inhibiting cell death (measured by Annexin V staining) and contributing to patient overall survival (measured by Kaplan-Meier estimate) were further confirmed by antimiR- 706 and CAAP1 knock-down. Results: We showed that Thapsigargin or Tunicamycin triggered ER stress leading to the induction of miR-706. miR-706 induction is dependent on PERK and its downstream regulator ATF4, as knocking-down of PERK and ATF4 suppressed miR-706 induction in response to ER stress. Knocking-down of miR-706 reduces cell death triggered by ER stress, indicating that miR-706 is pro-cell death microRNA. We further identified CAAP1 as a miR-706 target in regulating ER stress initiated cell death. Conclusion: Collectively, our results pointed to an ER signaling network consisting of proteins, microRNA and novel target. [ABSTRACT FROM AUTHOR]

In this study, arsenic trioxide (ATO) was encapsulated in liposomes via copper acetate (Cu(OAc) 2 ) gradients and high entrapment efficiency of over 80% was obtained. The average particle size and the zeta-potential of the liposomes were detected to be 115.1 ±29.1 nm and -21.97 ±0.6 mV, respectively. The TEM images showed rod-like precipitates in the inner aqueous phase, which was supposed be due to the formation of insoluble ATO --Cu complex. The in vitro drug release of ATO-Cu liposomes exhibited a sustained release over 72 h, and the release rates decreased with the increase of the pH of release media. Pharmacokinetic and tissue distribution studies of ATO liposomes showed significantly reduced plasma clearance rate, increased AUC 0-12 h and T 1/2, and improved tumor distribution of As compared to iv administration of ATO solution. The anti-tumor effect of ATO loaded liposomes to S180 tumor-bearing mice was significantly improved with a tumor inhibition rate of 61.2%, meanwhile the toxicity of encapsulated ATO was greatly decreased. In conclusion, ATO can be effectively encapsulated into liposomes by remote loading method via Cu(OAc) 2 gradients; the co-administration of ATO and Cu(II) via liposomal formulation may find wide applications in the treatment of various tumors. [ABSTRACT FROM AUTHOR]

Biogas residues and coal fly ash composite (CFA/BRC) were first investigated as novel heterogeneous catalysts for strengthening electro-Fenton (EF) of real British gas/Lurgi coal gasification wastewater. The prepared CFA/BRC was characterized by different techniques, i.e., SEM, XRD, BET surface area, XRF, and ICP-AES. The results indicated that CFA/BRC significantly improved performance of pollutant removal in EF across a wide pH range with current density of 10 mA/cm2 and catalyst dosage of 1.0 g/L, and the treated wastewater was more biodegradable than homogeneous EF. Meanwhile, CFA/BRC showed superior stability at successive 2,400-min runs, and leached concentrations of heavy metals were very low without the second pollutant. The change of concentrations of dissolved oxygen and electro-generated H2O2, and fluorescence test indicated that the novel catalyst could enhance H2O2 decomposition into more hydroxyl radicals, which was considered to be mainly responsible for the pollutant removal. And the results offered new insights into sustainable use of waste materials. [ABSTRACT FROM AUTHOR]

Medical waste management is an essential component of healthcare delivery globally due to the toxic and contagious potentials on human health and the environment. There are resource limitations in developing nations when it comes to the appropriate handling of medical wastes. In this article, we examined previous studies to evaluate the practices of medical waste management in China and Nigeria. Contextually, this work addresses medical waste practices in the context of waste generation, segregation, collection, storage, transportation, treatment and disposal. In addition to reviewing additional important aspects of medical waste management, the current study addresses potentials and challenges for efficient medical waste management in both countries. For this study; Scopus, Web of Science, Google Scholar, PubMed, Agencies, Conferences, National and International Conventions were searched from 1998 up to 2023 for all studies reporting medical waste management in China and Nigeria. To further guarantee that only resource materials with similar research interests in medical waste management were selected, a double screening process was employed. The challenges of medical waste management in both countries are limited financing, inadequate training, ineffective legislation, ineffective medical waste transport system and insufficient treatment technology. Furthermore, this study offers practical recommendations by identifying the particular areas that require attention and development, such as training of healthcare workers, adequate financing of medical waste management projects, including research and development on efficient toxic emission reducing technologies, and partnership with other relevant authorities and stakeholders to ensure enforcement of national and local legislation., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

A dilemma for current cancer therapy is surgical injury in addition to the toxicities and inefficiencies of systemic chemotherapy. Meanwhile, localized therapies have become a noticeable strategy. In this study, Cucurbitacin (Cuc)-loaded poly(lactic-co-glycolic acid) particles of different sizes (about 50 μm, 5 μm, and 270 nm, respectively) were prepared as the sustained-release system for intratumoral injection, and their physicochemical properties, in vitro cytotoxicity, particles-cells interactions, pharmacokinetics, and pharmacodynamics were systemically investigated for the first time. The results of cytotoxicity experiments and pharmacokinetic/pharmacodynamic studies indicated that the release patterns of the particles would strongly affect the biological efficiency not only at the cell level but also in two types of animal models. Cuc raw material and nanoparticles showed higher initial burst release in vitro, and higher drug concentration in tumor and plasma. Large particles (about 50 μm) showed lower initial burst and slow drug release, which would not supply enough amount of drug to inhibit the cancer cell growth during the whole treatment period. Particles with mean diameter of about 5 μm performed the best anti-melanoma efficiency both in vitro and in vivo. The release patterns, instead of the particles-cells interactions, would be the key factors to affect the biological effects of the particulate system for intratumoral injection., (Copyright © 2013 Wiley Periodicals, Inc.)