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© 2020 Elsevier B.V. Efficient drawing agents are essential in forward osmosis (FO) for clean water production. Monomeric thermo-responsive ionic liquid (IL) [N4444]2,4,6-MeBnSO3 was thoroughly investigated as a drawing agent in FO. The IL can be safely employed due to its thermal stability and low cytotoxicity. It has a van't Hoff factor i = 1.21, with sufficient ionic strength to generate osmotic pressure ~ 58.92 bars (2 M). FO operations especially under PRO mode demonstrate that 2 M [N4444]2,4,6-MeBnSO3 can induce competitive water flux Jv ~ 12.3 L m−2 h−1 with remarkably low reverse solute flux Js < 0.006 mol m−2 h−1 and specific reverse solute flux Js/Jv ~ 4.5 × 10−4 mol L−1. Using 0.6 M NaCl as feed demonstrates its consistency in desalinating seawater (Jv ~ 3.72 L m−2 h−1, Js ~ 0.004 mol m−2 h−1, and Js/Jv ~ 0.91 × 10−3 mol L−1). After FO, [N4444]2,4,6-MeBnSO3 can be effectively retrieved (~98%) through thermal precipitation at 60 °C, above its cloud point temperature (57 °C). Meanwhile, >99% of the remaining 2% can be recovered through reverse osmosis or membrane distillation to produce water effluents with non-toxic IL concentrations (≪100 mg L−1). Results indicate that thermo-responsive [N4444]2,4,6-MeBnSO3 is a promising alternative reusable drawing agent in FO process.

© 2020 Elsevier B.V. Efficient drawing agents are essential in forward osmosis (FO) for clean water production. Monomeric thermo-responsive ionic liquid (IL) [N4444]2,4,6-MeBnSO3 was thoroughly investigated as a drawing agent in FO. The IL can be safely employed due to its thermal stability and low cytotoxicity. It has a van't Hoff factor i = 1.21, with sufficient ionic strength to generate osmotic pressure ~ 58.92 bars (2 M). FO operations especially under PRO mode demonstrate that 2 M [N4444]2,4,6-MeBnSO3 can induce competitive water flux Jv ~ 12.3 L m−2 h−1 with remarkably low reverse solute flux Js < 0.006 mol m−2 h−1 and specific reverse solute flux Js/Jv ~ 4.5 × 10−4 mol L−1. Using 0.6 M NaCl as feed demonstrates its consistency in desalinating seawater (Jv ~ 3.72 L m−2 h−1, Js ~ 0.004 mol m−2 h−1, and Js/Jv ~ 0.91 × 10−3 mol L−1). After FO, [N4444]2,4,6-MeBnSO3 can be effectively retrieved (~98%) through thermal precipitation at 60 °C, above its cloud point temperature (57 °C). Meanwhile, >99% of the remaining 2% can be recovered through reverse osmosis or membrane distillation to produce water effluents with non-toxic IL concentrations (≪100 mg L−1). Results indicate that thermo-responsive [N4444]2,4,6-MeBnSO3 is a promising alternative reusable drawing agent in FO process.

Purpose: To determine the utility of ureteral stents in interstitial gynecological brachytherapy. Methods and Materials: We reviewed 289 patients with cervix cancer treated with high-dose-rate interstitial brachytherapy who did not have pretreatment hydronephrosis to determine the relative incidence of benign ureteral strictures after treatment. We also did comparative dosimetry analysis in five cases of high-dose-rate brachytherapy. Bilateral ureteral stents were placed during the procedure. Three dosimetry plans were created to determine the impact of modifying clinical target volume (CTV) and applying ureteral dose constraints. In Plan 1, the ureters were contoured and excluded from the CTV and 120% dose constraints were applied. In Plan 2, the ureters were contoured and excluded, but no dose constraints were applied to the ureter. In Plan 3, the CTV was created as if the location of the ureters was unknown and then ureteral dose was determined. Results: There were 11 ureteral strictures observed in 255 nonstented cases and 0 ureteral strictures in 34 stented cases. Plan 1 reduced the ureter dose (D0.1cc) by a median 22% (7.0-53.8%) compared with Plan 2 and by a median of 30.9% (12.3-65%). compared with Plan3. Conclusions: Placement of stents and ureteral dose constraints facilitates dosimetry and reduces the dose to ureters. Temporary ureteral stents prevent obstruction during interstitial gynecologic brachytherapy and allows the ureters to be addressed as an organ at risk.

Purpose: To determine the utility of ureteral stents in interstitial gynecological brachytherapy. Methods and Materials: We reviewed 289 patients with cervix cancer treated with high-dose-rate interstitial brachytherapy who did not have pretreatment hydronephrosis to determine the relative incidence of benign ureteral strictures after treatment. We also did comparative dosimetry analysis in five cases of high-dose-rate brachytherapy. Bilateral ureteral stents were placed during the procedure. Three dosimetry plans were created to determine the impact of modifying clinical target volume (CTV) and applying ureteral dose constraints. In Plan 1, the ureters were contoured and excluded from the CTV and 120% dose constraints were applied. In Plan 2, the ureters were contoured and excluded, but no dose constraints were applied to the ureter. In Plan 3, the CTV was created as if the location of the ureters was unknown and then ureteral dose was determined. Results: There were 11 ureteral strictures observed in 255 nonstented cases and 0 ureteral strictures in 34 stented cases. Plan 1 reduced the ureter dose (D0.1cc) by a median 22% (7.0-53.8%) compared with Plan 2 and by a median of 30.9% (12.3-65%). compared with Plan3. Conclusions: Placement of stents and ureteral dose constraints facilitates dosimetry and reduces the dose to ureters. Temporary ureteral stents prevent obstruction during interstitial gynecologic brachytherapy and allows the ureters to be addressed as an organ at risk.

A naphthoquinone inhibitor of human arylamine N-acetyltransferase 1 (hNAT1), a potential cancer biomarker and therapeutic target, has been reported which undergoes a distinctive concomitant color change from red to blue upon binding to the enzyme. Here we describe the use of in silico modeling alongside structure–activity relationship studies to advance the hit compound towards a potential probe to quantify hNAT1 levels in tissues. Derivatives with both a fifty-fold higher potency against hNAT1 and a two-fold greater absorption coefficient compared to the initial hit have been synthesized; these compounds retain specificity for hNAT1 and its murine homologue mNat2 over the isoenzyme hNAT2. A relationship between pKa, inhibitor potency and colorimetric properties has also been uncovered. The high potency of representative examples against hNAT1 in ZR-75-1 cell extracts also paves the way for the development of inhibitors with improved intrinsic sensitivity which could enable detection of hNAT1 in tissue samples and potentially act as tools for elucidating the unknown role hNAT1 plays in ER+ breast cancer; this could in turn lead to a therapeutic use for such inhibitors.

A naphthoquinone inhibitor of human arylamine N-acetyltransferase 1 (hNAT1), a potential cancer biomarker and therapeutic target, has been reported which undergoes a distinctive concomitant color change from red to blue upon binding to the enzyme. Here we describe the use of in silico modeling alongside structure–activity relationship studies to advance the hit compound towards a potential probe to quantify hNAT1 levels in tissues. Derivatives with both a fifty-fold higher potency against hNAT1 and a two-fold greater absorption coefficient compared to the initial hit have been synthesized; these compounds retain specificity for hNAT1 and its murine homologue mNat2 over the isoenzyme hNAT2. A relationship between pKa, inhibitor potency and colorimetric properties has also been uncovered. The high potency of representative examples against hNAT1 in ZR-75-1 cell extracts also paves the way for the development of inhibitors with improved intrinsic sensitivity which could enable detection of hNAT1 in tissue samples and potentially act as tools for elucidating the unknown role hNAT1 plays in ER+ breast cancer; this could in turn lead to a therapeutic use for such inhibitors.