Pyrite-activated persulfate oxidation and biological denitrification for effluent of biological landfill leachate treatment system.

The feasibility of pyrite as catalysts in the persulfate oxidation and electron donor for subsequent bacterial denitrification was investigated. The results demonstrated that pyrite-activated persulfate oxidation could efficiently degrade the organic matter in the effluent of biological landfill leachate treatment system, and COD removal efficiency of about 45% was achieved at the optimum parameters: pH = 6, pyrite dosage = 9.28 mM, dimensionless oxidant dose = 0.25. Among the dissolved organic matter, hydrophobic dissolved organic carbon (HO DOC), humic acids and building blocks were the main components. After the pyrite-activated persulfate oxidation, humic acids and HO DOC were primarily degraded, followed by building blocks, while low molecular weight neutrals were probably the degradation products. In the subsequent biological process, nitrate reduction was satisfactorily accomplished with autotrophic denitrification as the main pathway. When the influent nitrate concentration was about 180 mg L-1, the effluent nitrate concentration was stable below 20 mg L-1 with the nitrogen removal rate of about 108 mg L-1 d-1. To sum up, the pyrite-activated persulfate oxidation and the following biological denitrification was a feasible application in the effluent of biological landfill leachate treatment system.

Resuscitation, isolation and immobilization of bacterial species for efficient textile wastewater treatment: A critical review and update.

Given highly complex and recalcitrant nature of synthetic dyes, textile wastewater poses a serious challenge on surrounding environments. Until now, biological treatment of textile wastewater using efficient bacterial species is still considered as an environmentally friendly and cost-effective approach. The advances in resuscitating viable but non-culturable (VBNC) bacteria via signaling compounds such as resuscitation-promoting factors (Rpfs) and quorum sensing (QS) autoinducers, provide a vast majority of potent microbial resources for biological wastewater treatment. So far, textile wastewater treatment from resuscitating and isolating VBNC state bacteria has not been critically reviewed. Thus, this review aims to provide a comprehensive picture of resuscitation, isolation and application of bacterial species with this new strategy, while the recent advances in synthetic dye decolorization were also elaborated together with the mechanisms involved. Discussion was further extended to immobilization methods to tackle its application. We concluded that the resuscitation of VBNC bacteria via signaling compounds, together with biochar-based immobilization technologies, may lead to an appealing biological treatment of textile wastewater. However, further development and optimization of the integrated process are still required for their wide applications.

Antilung cancer effect of ergosterol and cisplatin-loaded liposomes modified with cyclic arginine-glycine-aspartic acid and octa-arginine peptides.

BACKGROUND: Lung cancer is one of the most important diseases threatening human health, and targeted therapy has become the main research direction. This work, therefore, aimed to develop cyclic arginine-glycine-aspartic (RGD) and octa-arginine (R8) peptide-modified ergosterol (ERG)-combined cisplatin (diamminedichloridoplatinum(II) [DDP]) liposomes (LIP) as a drug delivery system. METHODS: Soybean phospholipids (SPC) and cholesterol (Chol) were selected to prepare different LIPs: ERG-loaded LIP (ERG-LIP), DDP and ERG-LIP (DDP/ERG-LIP), R8 peptide-modified DDP and ERG-LIP (R8-DDP/ERG-LIP), and cyclic RGD and R8-DDP/ERG-LIP (RGD/R8-DDP/ERG-LIP). The quality, tumor sphere penetrating ability, in vitro cellular uptake, mechanism of cellular uptake, and in vitro cytotoxicity of RGD/R8-DDP/ERG-LIP were evaluated. RESULTS: The LIP quality evaluation revealed that RGD/R8-DDP/ERG-LIP is round with a double-layer structure. The average particle size, dispersion coefficient of the polydispersity index (PDI), and zeta potential of RGD/R8-DDP/ERG-LIP were 155.2 ±â€Š8.7 nm, 0.102, and 4.74 ±â€Š0.7 mV, respectively. Furthermore, the LIPs were stable in the serum, and obviously inhibited the growth of A549 lung cancer cells with RGD/R8-DDP/ERG-LIP exhibiting the strongest inhibitory effect. The highest cellular uptake rate, which was at 4 hours, was exhibited by RGD/R8-DDP/ERG-LIP in a concentration-dependent manner. CONCLUSION: The results showed that LIP uptake by A549 cells was mainly by the clathrin-mediated endocytosis pathway (chlorpromazine). The results also suggest that RGD/R8-DDP/ERG-LIP might be a promising drug delivery system to improve antilung cancer drug effect and tumor-targeting in vitro.

Broadband 2 × 2 lithium niobate electro-optic switch based on a Mach-Zehnder interferometer with counter-tapered directional couplers.

We demonstrate a broadband 2×2 electro-optic switch based on a Mach-Zehnder interferometer with counter-tapered directional couplers (DCs). The counter-tapered DC is introduced here to replace the conventional one formed with uniform waveguides so that a splitting ratio of 50%∶50% is much easier to be realized over a wide wavelength range and, hence, increase bandwidth of the switch. The proposed switch is fabricated with x-cut lithium niobate by the annealed proton exchange process. A comparison of several experimental devices, fabricated on the same chip with the conventional and different counter-tapered DCs, respectively, confirms the increase of the bandwidth and the improvement of the fabrication tolerance by using the counter-tapered DC. Our fabricated best device, which has a length of ∼22 mm, exhibits an ∼85 nm bandwidth for an extinction ratio (ER) higher than 15 dB and a maximum ER of ∼35 dB at 1563 nm at a driving voltage of 6.0 V. The insertion losses are less than 8.5 dB for all channels. Our proposed optical switch could find applications in wavelength-division-multiplexing optical communication systems.

Prolonged red cell storage before transfusion increases extravascular hemolysis.

BACKGROUND: Some countries have limited the maximum allowable storage duration for red cells to 5 weeks before transfusion. In the US, red blood cells can be stored for up to 6 weeks, but randomized trials have not assessed the effects of this final week of storage on clinical outcomes. METHODS: Sixty healthy adult volunteers were randomized to a single standard, autologous, leukoreduced, packed red cell transfusion after 1, 2, 3, 4, 5, or 6 weeks of storage (n = 10 per group). 51-Chromium posttransfusion red cell recovery studies were performed and laboratory parameters measured before and at defined times after transfusion. RESULTS: Extravascular hemolysis after transfusion progressively increased with increasing storage time (P < 0.001 for linear trend in the AUC of serum indirect bilirubin and iron levels). Longer storage duration was associated with decreasing posttransfusion red cell recovery (P = 0.002), decreasing elevations in hematocrit (P = 0.02), and increasing serum ferritin (P < 0.0001). After 6 weeks of refrigerated storage, transfusion was followed by increases in AUC for serum iron (P < 0.01), transferrin saturation (P < 0.001), and nontransferrin-bound iron (P < 0.001) as compared with transfusion after 1 to 5 weeks of storage. CONCLUSIONS: After 6 weeks of refrigerated storage, transfusion of autologous red cells to healthy human volunteers increased extravascular hemolysis, saturated serum transferrin, and produced circulating nontransferrin-bound iron. These outcomes, associated with increased risks of harm, provide evidence that the maximal allowable red cell storage duration should be reduced to the minimum sustainable by the blood supply, with 35 days as an attainable goal.REGISTRATION. ClinicalTrials.gov NCT02087514. FUNDING: NIH grant HL115557 and UL1 TR000040.

Measurement of HbA1c in Gingival Crevicular Blood Using a High-Pressure Liquid Chromatography Procedure.

OBJECTIVE: To validate an ion exchange high-pressure liquid chromatography (HPLC) method for measuring glycated hemoglobin (HbA1c) in gingival crevicular blood (GCB) spotted on filter paper, for use in screening dental patients for diabetes. METHODS: We collected the GCB specimens for this study from the oral cavities of patients during dental visits, using rigorous strategies to obtain GCB that was as free of debris as possible. The analytical performance of the HPLC method was determined by measuring the precision, linearity, carryover, stability of HbA1c in GCB, and correlation of HbA1c results in GCB specimens with finger-stick blood (FSB) specimens spotted on filter paper. RESULTS: The coefficients of variation (CVs) for the inter- and intrarun precision of the method were less than 2.0%. Linearity ranged between 4.2% and 12.4%; carryover was less than 2.0%, and the stability of the specimen was 6 days at 4°C and as many as 14 days at -70°C. Linear regression analysis comparing the HbA1c results in GCB with FSB yielded a correlation coefficient of 0.993, a slope of 0.981, and an intercept of 0.13. The Bland-Altman plot showed no difference in the HbA1c results from the GCB and FSB specimens at normal, prediabetes, and diabetes HbA1c levels. CONCLUSION: We validated an HPLC method for measuring HbA1c in GCB; this method can be used to screen dental patients for diabetes.