235 research outputs found

    Investigation of novel chemical in-situ treatment methods to mitigate cyanobacteria harmful algal blooms in surface waters

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    As water scarcity is becoming a universal problem to address, it is essential to maintain a high surface water quality and protect the biodiversity of current aquatic biotopes worldwide. Surface water contamination events caused by high nutrient and organic matter loads lead to the formation of cyano-HABs, which are mostly unpredictable. Therefore, highly efficient methods are required for the in-situ restoration of water quality. Several methods have been applied over the years to mitigate cyano-HABs with varying efficiencies. Current trends ask for more environmentally friendly approaches to be implemented in order to safeguard the overall aquatic ecosystems and reduce treatment costs. Hydrogen peroxide is currently being used as an emerging chemical alternative to copper algicides. Even though its broad application showed high efficiency on mitigating dense blooms, the required H2O2 doses for each case and treatment application differ, and in some instances high doses were applied with undesirable side effects on the entire lake ecosystem. Herein, calcium peroxide granules were utilized due to their slow H2O2 releasing properties, which simulate multiple liquid H2O2 doses. Specifically, granules were used in surface waters spiked with Microcystis, Aphanizomenon, and Cylindrospermopsis sp. and in actual water samples during blooming

    Comparison of UVC/S<sub>2</sub>O<sub>8</sub> <sup>2-</sup> with UVC/H<sub>2</sub>O<sub>2</sub> in terms of efficiency and cost for the removal of micropollutants from groundwater

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    This study compared the UVC/S2O82- system with the more commonly used AOP in water industry, UVC/H2O2, and examined whether the first one can be an economically feasible alternative technology. Atrazine and 4 volatile compounds (methyl tert-butyl ether, cis-dichlorethen, 1,4-dioxane and 1,1,1-trichloroethane) were chosen as model contaminants because they exhibit different susceptibility to UVC photolysis and AOPs. A collimated beam apparatus was utilized for the majority of the experiments (controlled environment, without mass transfer phenomena), while selected experiments were performed in a flow-through reactor to simulate industrial applications. Initial experiments on the activation of oxidants with a LP lamp indicated that S2O82- is photolysed about 2.3times faster than H2O2 and that the applied treatment times were not sufficient to utilize the majority of the oxidant. The effect of oxidants' concentrations were tested with atrazine alone and in the micropollutants' mixture and it was decided to use 11.8mgL-1 S2O82- and 14.9mgL-1 H2O2 for further testing since is closer to industrial applications and to minimize the residual oxidant concentration. Changes of the matrix composition of the treated water were investigated with the addition of chloride, bicarbonate and humic acids at concentrations relevant to a well-water-sample, the results showed that the system least affected was UVC/H2O2. Only when bicarbonate was used, UVC/S2O82- performed better. Overall, testing these systems with the mixture of micropollutants gave better insights to their efficiency than atrazine alone and UVC/S2O82- is recommended for selective oxidation of challenging matrices

    Effects of antifibrotic agents on TGF-β1, CTGF and IFN-γ expression in patients with idiopathic pulmonary fibrosis

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    SummaryIdiopathic pulmonary fibrosis (IPF) is a deadly disease, largely unresponsive to treatment with corticosteroids and immunosuppressives. The aim of this randomized, prospective, open-label study was to characterize the molecular effects of IFN-γ-1b and colchicine, on biomarkers expression associated with fibrosis (TGF-β, CTGF) and immunomodulatory/antimicrobial activity (IFN-γ), in the lungs of patients with IPF.Fourteen (14) patients with an established diagnosis of IPF received either 200μg of IFN-γ-1b subcutaneously three times per week, or 1mg of oral colchicine per day, for 24 months. Using RT-PCR assay, we evaluated the transcription levels of transforming growth factor β1 (TGF-β1), connective-tissue growth factor (CTGF), and interferon-γ (IFN-γ) genes in lung tissue before and after treatment with IFN-γ-1b or colchicine.Marked mRNA expression of TGF-β1 and CTGF, but complete lack of interferon-γ was detected in fibrotic lung tissue at entry. After treatment, both groups exhibited increased expression of IFN-γ gene at 6 months that was sustained at 24 months. The expression of CTGF and TGF-β1 remained almost stable before and after treatment, in the IFN-γ-1b group, while TGF-β1 was statistically decreased after therapy, in the colchicine group (p=0.0002). Significant difference in DLCO (% pred), was found between the two treatment groups in favor of IFN-γ-1b group (p=0.04). In addition, the IFN-γ-1b group showed stability in arterial PO2 while the colchicine group significantly deteriorated (p=0.02).In conclusion, we report the effect of antifibrotic agents (IFN-γ-1b and colchicine) in TGF-β, CTGF, and endogenous IFN-γ gene expression, in human fibrosis. However, extended studies are needed to verify the pathophysiological consequences of these findings

    Pirfenidone in idiopathic pulmonary fibrosis:expert panel discussion on the management of drug-related adverse events

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    Pirfenidone is currently the only approved therapy for idiopathic pulmonary fibrosis, following studies demonstrating that treatment reduces the decline in lung function and improves progression-free survival. Although generally well tolerated, a minority of patients discontinue therapy due to gastrointestinal and skin-related adverse events (AEs). This review summarizes recommendations based on existing guidelines, research evidence, and consensus opinions of expert authors, with the aim of providing practicing physicians with the specific clinical information needed to educate the patient and better manage pirfenidone-related AEs with continued pirfenidone treatment. The main recommendations to help prevent and/or mitigate gastrointestinal and skin-related AEs include taking pirfenidone during (or after) a meal, avoiding sun exposure, wearing protective clothing, and applying a broad-spectrum sunscreen with high ultraviolet (UV) A and UVB protection. These measures can help optimize AE management, which is key to maintaining patients on an optimal treatment dose.Correction in: Advances in Therapy, Volume 31, Issue 5, pp 575-576 , doi: 10.1007/s12325-014-0118-8</p

    A collaborative evaluation of LC-MS/MS based methods for BMAA analysis: soluble bound BMAA found to be an important fraction.

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    Exposure to β-Ν-methylamino-l-alanine (BMAA) might be linked to the incidence of amyotrophic lateral sclerosis, Alzheimer's disease and Parkinson's disease. Analytical chemistry plays a crucial role in determining human BMAA exposure and the associated health risk, but the performance of various analytical methods currently employed is rarely compared. A CYANOCOST initiated workshop was organized aimed at training scientists in BMAA analysis, creating mutual understanding and paving the way towards interlaboratory comparison exercises. During this workshop, we tested different methods (extraction followed by derivatization and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis, or directly followed by LC-MS/MS analysis) for trueness and intermediate precision. We adapted three workup methods for the underivatized analysis of animal, brain and cyanobacterial samples. Based on recovery of the internal standard D3BMAA, the underivatized methods were accurate (mean recovery 80%) and precise (mean relative standard deviation 10%), except for the cyanobacterium Leptolyngbya. However, total BMAA concentrations in the positive controls (cycad seeds) showed higher variation (relative standard deviation 21%-32%), implying that D3BMAA was not a good indicator for the release of BMAA from bound forms. Significant losses occurred during workup for the derivatized method, resulting in low recovery ( < 10%). Most BMAA was found in a trichloroacetic acid soluble, bound form and we recommend including this fraction during analysis
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