Critical conditions of struvite growth and recovery using MgO in pilot scale crystallization plant.

The struvite crystallization process can recover struvite crystals as a valuable slow-release fertilizer from the side stream of wastewater treatment plants (WWTPs). The purpose of this study is to demonstrate the crystal growth characteristics and determine the appropriate recovery criteria for a struvite crystallization pilot plant. A pilot plant (8.6 m3/d) was designed with a feeding system of MgO (magnesium oxide), a pH controller, and a hydrocyclone for recovering struvite; the plant was operated for 42 hours at a pH range of 8.25-8.5. The removal efficiencies for PO4-P and NH4-N were 82.5-90.7% and 13.4-22.9%, respectively. The struvite recovered from the hydrocyclone was sifted using standard sieves and analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The dry weight fraction of the precipitate in the 300-600 µm range increased gradually from 7% to 74% in 18 hours. The XRD analysis revealed that the crystalline structure of the precipitate in the 150-600 µm range indicates struvite without any peaks of MgO, Mg(OH)2, and MgCO3. This indicates that the critical conditions for recovering struvite from the side-stream of WWTPs are an operation period of 18 hours and a crystal size greater than 300 µm.

Resveratrol inhibits STAT3 signaling pathway through the induction of SOCS-1: Role in apoptosis induction and radiosensitization in head and neck tumor cells.

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3) is persistently activated in squamous cell carcinoma of the head and neck (SCCHN) and can cause uncontrolled cellular proliferation and division. HYPOTHESIS: Thus, its targeted abrogation could be an effective strategy to reduce the risk of SCCHN. Resveratrol is known for its anti-cancer efficacy in a variety of cancer models. STUDY DESIGN: The effect resveratrol on STAT3 activation, associated protein kinases, phosphatases, cellular proliferation and apoptosis was investigated. METHODS: We evaluated the effect of resveratrol on STAT3 signaling cascade and its regulated functional responses in SCCHN cells. RESULTS: We found that HN3 and FaDu cells expressed strongly phosphorylated STAT3 on both tyrosine 705 and serine 727 residues as compared to other SCCHN cells. The phosphorylation was completely suppressed by resveratrol in FaDu cells, but not substantially in HN3 cells. STAT3 suppression was mediated through the inhibition of activation of upstream JAK2, but not of JAK1 and Src kinases. Treatment with the protein tyrosine phosphatase (PTP) inhibitor pervanadate reversed the resveratrol-induced down-regulation of STAT3, thereby indicating a critical role for a PTP. We also found that resveratrol induced the expression of the SOCS-1 protein and mRNA. Further, deletion of SOCS-1 gene by siRNA suppressed the induction of SOCS-1, and reversed the inhibition of STAT3 activation. Resveratrol down-regulated various STAT3-regulated gene products, inhibited proliferation, invasion, as well as induced the cell accumulation in the sub-G1 phase and caused apoptosis. Beside, this phytoalexin also exhibited the enhancement of apoptosis when combined with ionizing radiation treatment. CONCLUSION: Our results suggest that resveratrol blocks STAT3 signaling pathway through induction of SOCS-1, thus attenuating STAT3 phosphorylation and proliferation in SCCHN cells.

Comparison of chemoembolization with and without radiation therapy and sorafenib for advanced hepatocellular carcinoma with portal vein tumor thrombosis: a propensity score analysis.

PURPOSE: To compare efficacy of transarterial chemoembolization with and without radiation therapy (RT) versus sorafenib for advanced hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT). MATERIALS AND METHODS: This single-center retrospective study involved 557 patients with HCC with PVTT who initially received chemoembolization (1997-2002; n = 295), chemoembolization and RT (2003-2008; n = 196), or sorafenib (2009-2012; n = 66) according to eligibility criteria among an initial population of 617. The three groups were divided into three pairs (chemoembolization vs chemoembolization/RT, chemoembolization vs sorafenib, and chemoembolization/RT vs sorafenib), and time to progression (TTP) and overall survival (OS) were compared by propensity-score analyses. RESULTS: The chemoembolization/RT group had longer median TTP and OS than the chemoembolization-alone and sorafenib groups (P < .001). Multivariate Cox analysis revealed that chemoembolization/RT treatment was an independent predictor of favorable TTP and OS. In the matched cohort, median TTP and OS were significantly longer in the chemoembolization/RT group than the chemoembolization-alone group (102 pairs; TTP, 8.7 mo vs 3.6 mo [P < .001]; OS, 11.4 mo vs 7.4 mo [P = .023]) or the sorafenib group (30 pairs; TTP, 5.1 mo vs 1.6 mo [P < .001]; OS, 8.2 mo vs 3.2 mo [P < .001]), in agreement with the inverse probability of treatment weighted (IPTW) outcomes. In matching analyses, the chemoembolization-alone group had longer median TTP and OS than the sorafenib group (46 pairs; TTP, 3.4 mo vs 1.8 mo [P < .001]; OS, 5.9 mo vs 4.4 mo [P = .003]). There was no significant difference in terms of OS with the IPTW approach (P = .108), but there was one in terms of TTP (P < .001). CONCLUSIONS: Within the limitation of a retrospective study, the present data indicate that transarterial chemoembolization combined with RT could be considered as an alternative to the standard sorafenib in the treatment of patients with advanced-stage HCC with PVTT.