Assessment of biodegradation potential at a site contaminated by a mixture of BTEX, chlorinated pollutants and pharmaceuticals using passive sampling methods; Case study

The present study describes a pilot remediation test of a co-mingled plume containing BTEX, chlorinated pollutants and pharmaceuticals. Remediation was attempted using a combination of various approaches, including a pump and treat system applying an advanced oxidation process and targeted direct push injections of calcium peroxide. The remediation process was monitored intensively and extensively throughout the pilot test using various conventional and passive sampling methods, including next-generation amplicon sequencing. The results showed that the injection of oxygen-saturated treated water with residual hydrogen peroxide and elevated temperature enhanced the in situ removal of monoaromatics and chlorinated pollutants. In particular, in combination with the injection of calcium peroxide, the conditions facilitated the in situ bacterial biodegradation of the pollutants. The mean groundwater concentration of benzene decreased from 1349 μg·L− 1 prior to the test to 3 μg·L− 1 within 3 months after the calcium peroxide injections; additionally, monochlorobenzene decreased from 1545 μg·L− 1 to 36 μg·L− 1, and toluene decreased from 143 μg·L− 1 to 2 μg·L− 1. Furthermore, significant degradation of the contaminants bound to the soil matrix in less permeable zones was observed. Based on a developed 3D model, 90% of toluene and 88% of chlorobenzene bound to the soil were removed during the pilot test, and benzene was removed almost completely. On the other hand, the psychopharmaceuticals were effectively removed by the employed advanced oxidation process only from the treated water, and their concentration in groundwater remained stagnant due to inflow from the surroundings and their absence of in situ degradation. The employment of passive sampling techniques, including passive diffusion bags (PDB) for volatile organic pollutants and their respective transformation products, polar organic compound integrative samplers (POCIS) for the pharmaceuticals and in situ soil microcosms for microbial community analysis, was proven to be suitable for monitoring remediation in saturated zones

Pharmaceuticals, benzene, toluene and chlorobenzene removal from contaminated groundwater by combined UV/H2O2 photo-oxidation and aeration

This study was performed to test the feasibility of several decontamination methods for remediatingheavily contaminated groundwater in a real contaminated locality in the Czech Republic, where apharmaceuticals plant has been in operation for more than 80 years. The site is polluted mainly byrecalcitrant psychopharmaceuticals and monoaromatic hydrocarbons, such as benzene, toluene andchlorobenzene. For this purpose, an advanced oxidation technique employing UV radiation withhydrogen peroxide dosing was employed, in combination with simple aeration pretreatment. The resultsshowed that UV/H2O2was an efficient and necessary step for degradation of the pharmaceuticals;however, the monoaromatics were already removed during the aeration step. Characterization of theremoval mechanisms participating in the aeration revealed that volatilization, co-precipitation andbiodegradation contributed to the process. Thesefindings were supported by bacterial metabolite ana-lyses, phospholipid fatty acid analysis, qPCR of representatives of the degradative genes and detailedcharacterization of the formed precipitate using M€ossbauer spectroscopy and scanning electron micro-scopy. Further tests were carried out in a continuous arrangement directly connected to the wells alreadypresent in the locality. The results documented the feasibility of combination of the photo-reactoremploying UV/H2O2together with aeration pretreatment for 4 months, where the overall decontami-nation efficiency ranged from 72% to 99% of the pharmaceuticals. We recorded even better results for themonoaromatics decontamination except for one month, when we encountered some technical problemswith the aeration pump. This demonstrated the necessity of using the aeration step

Transcription factor c-Myb: novel prognostic factor in osteosarcoma

The transcription factor c-Myb is an oncoprotein promoting cell proliferation and survival when aberrantly activated/expressed, thus contributing to malignant transformation. Overexpression of c-Myb has been found in leukemias, breast, colon and adenoid cystic carcinoma. Recent studies revealed its expression also in osteosarcoma cell lines and suggested its functional importance during bone development. However, the relevance of c-Myb in control of osteosarcoma progression remains unknown. A retrospective clinical study was carried out to assess a relationship between c-Myb expression in archival osteosarcoma tissues and prognosis in a cohort of high-grade osteosarcoma patients. In addition, MYB was depleted in metastatic osteosarcoma cell lines SAOS-2 LM5 and 143B and their growth, chemosensitivity, migration and metastatic activity were determined. Immunohistochemical analysis revealed that high c-Myb expression was significantly associated with poor overall survival in the cohort and metastatic progression in young patients. Increased level of c-Myb was detected in metastatic osteosarcoma cell lines and its depletion suppressed their growth, colony-forming capacity, migration and chemoresistance in vitro in a cell line-dependent manner. MYB knock-out resulted in reduced metastatic activity of both SAOS-2 LM5 and 143B cell lines in immunodeficient mice. Transcriptomic analysis revealed the c-Myb-driven functional programs enriched for genes involved in the regulation of cell growth, stress response, cell adhesion and cell differentiation/morphogenesis. Wnt signaling pathway was identified as c-Myb target in osteosarcoma cells. Taken together, we identified c-Myb as a negative prognostic factor in osteosarcoma and showed its involvement in the regulation of osteosarcoma cell growth, chemosensitivity, migration and metastatic activity