Overhydration Research Articles

#500 Monitoring relative blood volume and calf bioimpedance in hemodialysis patients

Abstract Background and Aims Measurements of relative blood volume (RBV, %) are used to monitor the relative change in blood plasm during hemodialysis (HD). Continuous measurement of calf extracellular volume (cECV) during HD allows the calculation of relative change in cECV (RCE). RCE was defined as the ratio of cECV to its initial value, cECV0 (RCE = 100 × cECV/cECV0, %). The aim of our study was to investigate the relationship between RBV, RCE and the occurrence of intradialytic hypotension (IDH). Method Fifty-five HD patients were studied. We reduced the HD target weight stepwise by 0.1 to 0.2 kg per HD session until clinically defined IDH symptoms occurred. RBV was monitored using the blood volume monitor (BVM, Fresenius Medical Care, Germany). Whole body bioimpedance spectroscopy (wBIS) provided whole body ECV (wECV) and intracellular volume (wICV) pre and post HD. Continuous calf bioimpedance (Hydra 4200, Xitron Technologies, San Diego, CA USA) provided cECV during HD. Pre HD overhydration (OH) was calculated according to whole body composition model (Chamney et al, Am J Clin Nutr 2007; 85:80). Total number of HD sessions in all patients were divided into three groups according to the pre HD OH: 1) normal OH (NOH, OH < 1 L), 2) moderate OH (MOH, 1 ≤ OH < 4 L) and 3) severe OH (SOH, OH ≥ 4 L). Furthermore, patients were stratified by the presence or absence of IDH in each hydration group. Ultrafiltration rate (UFR), pre HD body weight, body mass index (BMI) were measured. Minimal RBV (RBVMin) and minimal RCE (RCEMin) in each HD session were recorded. These measures represent maximum reduction of fluid in the intravascular and interstitial spaces, respectively. Reducing cECV can be considered as refilling fluid from interstitial transferring to intravascular space driving by ultrafiltration. The difference between RCEMin and RBVMin was defined as vascular refilling capacity. Linear mixed-effect logistic regression (LMELR) analysis was applied to explore relationships between IDH with RBVMin, RCEMin, wECV and BMI. Results We studied 621 HD sessions in 55 patients. MOH was present in 57%, SOH in 22% and NOH in 21% of total number of HD sessions respectively. There were significant differences in age, UFR, RBVMin, RCEMin, pre HD wECV, BMI between three groups, while the IDH rate did not differ significantly (Table 1). RBVMin was inversely correlated with UFR (Fig. 1) in all measurements. Pre HD wECV was the only factor associated with IDH in overall measurement. Pre HD wECV was significantly lower in IDH than in non-IDH patients in the NOH group (Fig. 2). In the MOH group, UFR and RCEMin-RBVMin were higher in IDH than in non-IDH patients (Fig. 3a and Fig. 3b). In the SOH group, Pre HD OH is the major factor associated with IDH (Fig. 4). Conclusion This study found that the major factors leading to IDH are 1) lower hydration status; 2) relative higher UFR; and 3) the limited refilling capacity. RBVMin correlated with UFR, but it did not predict IDH. Combined analysis of RBV and calf bioimpedance may provide a means to quantitate the fluid transport between intravascular and interstitial compartments and could add to an early IDH warning system.

#1017 External validation of a machine learning model for the prediction of bioimpedance-determined pre-dialysis overhydration

Abstract Background and Aims An accurate, automated determination of volume status in dialysis patients using a reproducible standard would be clinically useful. We have previously developed a machine learning model for the prediction of pre-dialysis overhydration (OH) index (litres) from the Fresenius Body Composition Monitor (BCM). External validation is a requisite step before the clinical implementation of a machine learning model. Method Data analyses were performed using Python. An XGBoost regressor model was internally developed and validated in a Fresenius dataset of 9,452 patients and 279,324 BCM target events from the Czech Republic and Italy between January 2016 and December 2022. An XGBoost regressor model with 60 input variables including the average BCM OH value in the preceding year, 2-week moving averages of dialysis session data and biomarkers/ medications data from the preceding 13 weeks demonstrated the best performance of the models tested. The external validation (EV) dataset consisted of 24 patients from a 7-week observational study in a single centre, in Beaumont, Ireland comprising 94 BCM sessions and 650 haemodialysis sessions. Individualised predictions were compared with BCM measures and clinical volume assessments performed at 2-week intervals. Mean squared error (MSE), Root mean square error (RMSE), and Bland-Altman plots were used for continuous outcomes. Precision, recall and F1 score were used to assess the algorithm's performance in predicting the following fluid categories: overhydration ≥1.1L, normohydration −1.1L to 1.1L, underhydration ≤-1.1L. Normohydration weight was calculated by subtracting the predicted OH index from the pre-dialysis weight. Results There was performance degradation between the internal validation (IV) and EV set. The RMSE for pre-dialysis OH was 1.04 kg in the IV set and 1.5 kg in the EV set. This could be attributed to differences in the distribution of the outcome variable (BCM OH validation dataset=1.97 ± 1.56 kg*, EV dataset=0.89 ± 1.7 kg), and the case-mix. The RMSE for normohydration weight was 1.86 kg in the EV set. Wide limits of agreement were noted on a Bland Altman plot comparing the average of BCM and predicted values plotted against the difference in values (mean bias - 0.54, 95% limits of agreement -3.44 kg to 2.36 kg). The overall accuracy of the model in predicting fluid classes was 60%. A histogram showed a close alignment in the distributions of predicted normohydration weights and BCM values. Conclusion The performance of the algorithms degraded between the internal validation and external validation datasets. However, the pre-dialysis algorithm showed an ability to discriminate fluid categories compared to nursing staff and the overall accuracy was acceptable. Additional training of the algorithms using fluid status classes would be expected to improve the precision of predictions. *Values less than the 1st percentile of – 2.17 L were excluded.

#1514 Elevated FGF23 increases systolic, and diastolic blood pressure, and pulse pressure in non-dialysis CKD patients

Abstract Background and Aims Arterial stiffness is associated with high blood pressure. Elevated fibroblast growth factor 23 (FGF23) has been shown to produce changes in the phenotype of vascular smooth muscle cells that may cause an increase in arterial stiffness and an impairment of vascular function. Thus, we aimed to evaluate whether, in g5 non-dialysis CKD patients, higher concentration FGF23 is associated with elevated systolic (SBP), diastolic blood pressure (DBP), and pulse pressure (PP). Method We included 159 g5 non-dialysis CKD patients. Generalized additive models analyzed the association between intact FGF23, SBP, DBP, and PP. The body composition measurement was used to evaluate overhydration (OH). Given the potential non-linear relationship between iFGF23, with the other variables, iFGF23 was categorized into tertiles (T1 ≤ 389 pg/ml, T2 = 389—517 pg/ml, and T3 = >517 pg/ml). Results The mean age was 65.2 ± 14.7 years. 46% (n = 73) were female. The mean values of SBP and DBP were 158.8 ± 21.3 mmHg, and 87.2 ± 12.3 mmHg respectively, and the PP was 76.6 ± 20 mmHg. The median concentration of iFGF23 was 468.3 (268.8—904.9) pg/ml. It was observed a positive correlation between iFGF23 tertiles and SBP (p < 0.001), DBP (<0.01), PP (p = 0.02), and OH (p < 0.01) (Fig. 1). Multivariate generalized additive models showed an independent association of iFGF23 with SBP (Beta 5.16, CI 34-68), DBP (Beta 38.7, CI 24-53), and PP (Beta 36.3, CI 22.2-50.4). This association was not influenced by OH (%). Residual diuresis did not attenuate the association of iFGF23 with SBP, DBP, and PP. Conclusion Elevated FGF23 was associated with higher SBP, DBP, and PP in g5 non-dialysis CKD patients. This association was not modified by OH and residual diuresis.

Quality by design−aided acid-free synthesis of self P, N, S-doped black seed-derived carbon quantum dots for application as a nanosensor for eltrombopag environmental and bioanalysis and pharmacokinetic assay

Herein, we developed a rapid, one-step, and cost-effective methodology based on the fabrication of water-soluble self-nitrogen, sulfur, and phosphorus co-doped black seed carbon quantum dots (BSQDs) via microwaveirradiation in six minutes. Our synthesis approach is superior to those in the literature as they involved long-time heating (12 h) with sulfuric acid and sodium hydroxide and/or high temperatures (200 °C). A full factorial design was applied to obtain the most efficient synthesis conditions.BSQDs displayed excitation-independent emissions, demonstrating the purity of the synthesized BSQDs, with a maximum fluorescence at 425 nm after excitation at 310 nm. Eltrombopag olamine is an anti-thrombocytopenia drug that is also reported to cause toxicity in river water based on its Persistence, Bioaccumulation, and Toxicity (PBT). The synthesized BSQDs were employed as the first fluorometric sensor for environmental and bioanalysis of eltrombopag. The fluorescence of BSQDs decreased with increasing concentrations of eltrombopag, with excellent selectivity and sensitivity down to 30 ppb. BSQDs were successfully applied as sensing probes for the detection of eltrombopag in medical tablets, spiked and real human plasma samples, and river water samples, with an overall recovery of at least 97 %. The good tolerance to high levels of foreign components and co-administered drugs indicates good selectivity and versatility of the proposed methodology. Plasma pharmacokinetic parameters such as t1/2, Cmax, and t max of eltrombopag were evaluated to be 9.91 h, 16.0 μg mL−1, and 5 h, respectively. Moreover, the green character of the BSQDs as a sensor was proved by various analytical greenness scales.

#201 Bedside lung ultrasound and bioimpedance spectroscopy for assessment of volume status in chronic kidney disease patients on hemodialysis

Abstract Background and Aims Fluid balance is important in patients with chronic kidney disease undergoing hemodialysis (HD). Majority of HD treatment incorporate a prescription for fluid removal targeted to patient's dry weight. Overestimation of dry weight causes hypertension, left ventricular hypertrophy and heart failure, while underestimation is responsible for chronic dehydration leading to the risk of hypotension. Both complications have a significant impact on the overall morbidity and mortality. Dry weight of the patient is usually assessed by using clinical parameters (edema, BP, JVP etc.), Biochemical parameters (BNP, ANP), Bioimpedance Spectroscopy (BIS) or IVC diameter and collapsibility on ultrasound (VCI index). The use of chest ultrasound to detect lung water has recently received growing attention in clinical research. Ultrasonographic lung comets (counting B-lines artifact) evaluate extravascular lung water and hence is considered as a useful tool to evaluate the hydration status of hemodialysis patients. This study aims to compare the efficacy of body fluid volume status and lung water assessment by clinical methods, Ultrasound chest and Bioimpedance Spectroscopy in chronic kidney disease patients on hemodialysis. Method A cross-sectional study was conducted over a period of 6 months. Dry weight of the patient was assessed by the attending nephrologist based on clinical criteria such as: weight, blood pressure, presence of edema or vascular congestion. A Longitudinal Ultrasound scan of the chest was performed using MicroMaxx Ultrasound System with patient in supine position from second to fourth intercostal space of left hemi-thorax and second to fifth intercostal space of right hemi-thorax along parasternal, midclavicular, anterior axillary and midaxillary lines of each side in a total of 28 sectors. B-lines were defined as hyperechogenic linear artifact emerging from the pleural line, up to the bottom of the screen. Pre and Post dialysis comet score was determined by calculating the total B-lines in each sector. Bioimpedance spectroscopy using Bodystat QuadScan 4000 was performed. Pre and post dialysis total body water (TBW), intracellular water (ICW), extracellular water (ECW) and residual fluid overload (ECW pre HD- ECW post HD) were recorded. Results We conducted 100 assessments on 34 patients presenting to the hospital for maintenance hemodialysis. The mean age of the study population was 54.3 + 11 years with a sex ratio (M/F) of 6:1. Mean systolic blood pressure was 141.1 + 19 mmHg and diastolic blood pressure was 83 + 9.3 mmHg with 3 episodes of intradialytic hypotension. The mean dry weight was 59.8 + 10 Kg and weight gain by clinical assessment was 2.1 + 1.5 Kg. Comet score assessed by ultrasound chest had a mean of 4.54 + 2.53 before dialysis and 1.73 ± 1.36 after dialysis. Residual fluid overload on Bio impedance spectroscopy was 1.11 ± 0.85 litre. The residual fluid overload on Bio impedance spectroscopy and lung ultrasound comet score after dialysis had a significant correlation (p value <0.0001). Of the 100 assessments, 40% had fluid overload after dialysis on Bio impedance and 35% had lung congestion on ultrasound chest even after achieving euvolemia according to the dry weight assessed clinically. Conclusion Lung comets on ultrasound chest and residual volume on bio impedance spectroscopy may precede the development of clinical sign and symptoms in a patient. Therefore, these methods are superior to clinical volume status assessment in chronic kidney disease patients on hemodialysis.

A novel nano-drug delivery system of glycyrrhetinic acid-mediated intracellular breakable brucine for enhanced anti-hepatitis B efficacy.

Background: Glycyrrhetinic acid-mediated brucine self-assembled nanomicelles enhance the anti-hepatitis B properties of brucine by improving its water solubility, short half-life, toxicity, and side effects. Brucine (B) is an indole alkaloid extracted from the seeds of Strychnos nux-vomica (Loganiaceae). Purpose: To assess the efficacy of the Brucine-Glycyrrhetnic acid-Polyethylene glycol-3,3'-dithiodipropionic acid-Glycerin monostearate (B-GPSG) in treating hepatitis B, its potential to protect against acute liver injury caused by d-galactosamine and its anti-hepatoma activities were studied. Research Design: The concentration of B-GPSG used in the in vivo and in vitro experiments was 0.63mg/mL. The rats injected with d-GalN (450mg/kg) were used as liver injury models. The rats were separated into normal, model, positive, positive control, B-PSG and B-GPSG groups. Hepatoma cells expressing HBV HepG2.2.15 were used for in vitro experiments. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, plate cloning, Hoechst staining and flow cytometry were conducted to explore the mechanism of B-GPSG against hepatitis B. Results: Compared with the model group, the liver coefficient of B-GPSG group decreased (4.59 ± 0.17 vs 5.88 ± 0.42), the content of MDA in rat liver homogenate decreased (12.54 ± 1.81 vs 23.05 ± 2.98), the activity of SOD increased, the activity of ALT and AST in rat serum decreased. In vitro, the IC50 values of B-GPSG group decreased. B-GPSG group effectively inhibited the proliferation and migration of HepG2.2.15 cells. Conclusions: The hepatoprotective effects of B-GPSG nanomicelles, which are attributed to their GA-mediated liver targeting and synergistic actions with brucine, suggest their therapeutic potential against hepatitis B. This development opens up new possibilities for the application of traditional Chinese medicine and nanomedicine in anti-hepatitis B.

Patient’s Satisfaction Post-Transurethral Resection of the Prostate with Monopolar and Bipolar for Benign Prostate Hyperplasia

Transurethral resection of the prostate (TURP), either bipolar or monopolar, is a surgical treatment for benign prostatic hyperplasia, which has similar effectiveness in reducing international prostate symptom score, increasing men peak flow rates, and reducing post-void residual volume. However, bipolar TURP (B-TURP) can reduce the incidence of bleeding and dilutional hyponatremia. This study aims to evaluate the effectiveness of the level of patient satisfaction between Monopolar-TURP (M-TURP) and B-TURP. 82 patients at three hospitals in Denpasar City were eligible as subjects based on inclusion criteria, consisting of 41 patients for each procedure. The recruitment method used consecutive sampling from March to August 2019. The patient’s demographics as baseline data were recorded. The level of patient satisfaction was recorded for one month after surgery through the SF-36 questionnaire. The baseline sample’s characteristics before surgery in both groups were statistically identical. In evaluating patient satisfaction levels, there are significant differences where TURP (B-TURP) is better in the domain of vitality (p=0.001), social function (p=0.005), pain (p=0.002), and general health (p=0.001). B-TURP resulted in an increasing level of patient satisfaction better than M-TURP.

Patient’s Satisfaction Post-Transurethral Resection of the Prostate with Monopolar and Bipolar for Benign Prostate Hyperplasia

Transurethral resection of the prostate (TURP), either bipolar or monopolar, is a surgical treatment for benign prostatic hyperplasia, which has similar effectiveness in reducing international prostate symptom score, increasing men peak flow rates, and reducing post-void residual volume. However, bipolar TURP (B-TURP) can reduce the incidence of bleeding and dilutional hyponatremia. This study aims to evaluate the effectiveness of the level of patient satisfaction between Monopolar-TURP (M-TURP) and B-TURP. 82 patients at three hospitals in Denpasar City were eligible as subjects based on inclusion criteria, consisting of 41 patients for each procedure. The recruitment method used consecutive sampling from March to August 2019. The patient’s demographics as baseline data were recorded. The level of patient satisfaction was recorded for one month after surgery through the SF-36 questionnaire. The baseline sample’s characteristics before surgery in both groups were statistically identical. In evaluating patient satisfaction levels, there are significant differences where TURP (B-TURP) is better in the domain of vitality (p=0.001), social function (p=0.005), pain (p=0.002), and general health (p=0.001). B-TURP resulted in an increasing level of patient satisfaction better than M-TURP.

The use of epibenthic copepod Tisbe biminiensis nauplii to assess the toxicity of seawater samples in Suape Bay (state of Pernambuco; Brazil)

Bioassays to determine the toxicity of water have been used worldwide as a tool of environmental monitoring. In the present study, the epibenthic copepod Tisbe biminiensis nauplius is proposed as a test organism for samples of seawater. Survival and the percentage of development from nauplius to copepodite were compared to the embryo-larval development of the sea urchin L. variegatus exposed to the same samples from the Suape estuarine system (state of Pernambuco, Brazil) collected in 2009. T. biminiensis naupliar development displayed a similar sensitivity to that found with the sea urchin embryos, mainly when simple t-test (not bioequivalent corrected) was used for sea urchin data. However, a lower sensitivity of copepod survival was found. The aluminium, iron and lead concentrations in surface waters were sometimes higher than Brazilian guidelines for estuarine water, probably due to dredging activities and anthropogenic contamination. These metals could be at least partially responsible for the toxic effects found at different stations and months. The results indicated that naupliar development of this epibenthic copepod is appropriate for the assessment of toxicity levels in seawater samples.

Heavy Metal Pollution Status in The Main Surface Waters of The N'djili River Basin in Kinshasa, Democratic Republic of Congo: A Review with Application and Evaluation of Pollution Indices Evaluation

The aim of this study was to assess heavy metal pollution in the surface waters of the N'djili river watershed, as well as to determine the main sources of this pollution and their impact on water quality. Five sampling sites were selected in the watershed, representing a variety of urban and industrial influences. In these samples, trace metals such as lead (Pb), cadmium (Cd) and arsenic (As) were measured by atomic absorption spectrometry. The respective mean concentrations of lead (Pb), cadmium (Cd) and arsenic (As) in the surface waters of the N'djili basin are 0.066 mg/L, 0.006 mg/L and 0.310 mg/L. The mean value of the degree of contamination (Dc) in the surface waters of the N'djili basin is greater than 3, indicating heavy contamination of these waters (Lukaya river, Matete river, N'djili river, Ntshuenge river, Ngwele river). The average values of for the trace metal pollution index (HPI) are below the threshold value of 100, so overall, these waters are not very polluted. Nevertheless, particularly high concentrations were observed in the waters of the Matete River, with values exceeding 100, indicating severe localized pollution. Correlation analysis between trace metals and HPI indicates that lead and cadmium are the main contributors to surface water toxicity in the N'djili basin. These results highlight the urgent need to develop targeted strategies to reduce pollution in order to preserve public health and aquatic ecosystems.

Mammalian Cell Genotoxicity of Potable Reuse and Conventional Drinking Waters.

Potable reuse water is increasingly part of the water supply portfolio for municipalities facing water shortages, and toxicity assays can be useful for evaluating potable reuse water quality. We examined the Chinese hamster ovary cell acute direct genotoxicity of potable reuse waters contributed by disinfection byproducts (DBPs) and anthropogenic contaminants and used the local conventional drinking waters as benchmarks for evaluating potable reuse water quality. Our results showed that treatment trains based on reverse osmosis (RO) were more effective than RO-free treatment trains for reducing the genotoxicity of influent wastewaters. RO-treated reuse waters were less genotoxic than the local tap water derived from surface water, whereas reuse waters not treated by RO were similarly genotoxic as the local drinking waters when frequent replacement of granular activated carbon limited contaminant breakthrough. The genotoxicity contributed by nonvolatile, uncharacterized DBPs and anthropogenic contaminants accounted for ≥73% of the total genotoxicity. The (semi)volatile DBPs of current research interest contributed 2-27% toward the total genotoxicity, with unregulated DBPs being more important genotoxicity drivers than regulated DBPs. Our results underscore the need to look beyond known, (semi)volatile DBPs and the importance of determining whole water toxicity when assessing the quality of disinfected waters.

Silica-assisted Pt1/CeO2 single-atom catalyst for enhancing the catalytic combustion performance of VOCs by inducing H2O activation

Due to the competitive adsorption of water and reactants at the active sites, especially the water toxicity of platinum-based single-atom catalysts, it is of great importance to improve the low-temperature activity and the water resistance of catalysts for the catalytic combustion of benzene. In this work, it was found that constructing a SiO2 shell layer on the catalyst not only "immobilized" the Pt single atoms, but also effectively weakened the adsorption of H2O on the Pt active sites, which resulted in excellent water resistance of the Pt single-atom catalysts. The comprehensive characterization results demonstrated that the participation of water molecules in the catalytic oxidation reaction of benzene could be effectively promoted by enhancing the strong metal-support interactions (SMSI) at the core-shell interface, which would change the electronic structure of the catalyst surface. As a result, the Pt1/CeO2@SiO2-4 catalyst with a Pt-O-Si active interface exhibits good activity (T = 190 °C) as well as excellent water resistance under the wet condition (10 vol%). This project provides a promising strategy for the design of Pt-based core-shell catalysts with excellent water resistance.

Arginine vasopressin deficiency: diagnosis, management and the relevance of oxytocin deficiency.

Polyuria-polydipsia syndrome can be caused by central diabetes insipidus, nephrogenic diabetes insipidus or primary polydipsia. To avoid confusion with diabetes mellitus, the name 'central diabetes insipidus' was changed in 2022 to arginine vasopressin (AVP) deficiency and 'nephrogenic diabetes insipidus' was renamed as AVP resistance. To differentiate the three entities, various osmotic and non-osmotic copeptin-based stimulation tests have been introduced in the past decade. The hypertonic saline test plus plasma copeptin measurement emerged as the test with highest diagnostic accuracy, replacing the water deprivation test as the gold standard in differential diagnosis of the polyuria-polydipsia syndrome. The mainstay of treatment for AVP deficiency is AVP replacement with desmopressin, a synthetic analogue of AVP specific forAVP receptor 2 (AVPR2), which usually leads to rapid improvements in polyuria and polydipsia. The main adverse effect of desmopressin is dilutional hyponatraemia, which can be reduced by regularly performing the so-called desmopressin escape method. Evidence from the past few years suggests an additional oxytocin deficiency in patients with AVP deficiency. This potential deficiency should be further evaluated in future studies, including feasible provocation tests for clinical practice and interventional trials with oxytocin substitution.

Effects of d-allose on anti-brain edema effects and reduction of tumor necrosis factor-alpha and interleukin-6 in the water intoxication model

BackgroundRare sugars, which exist only in very small quantities in nature, have recently attracted attention for their various biological functions in medicine. Among them, d-allose is known to have cytoprotective effects by antioxidant effects. In this study, we investigated whether the antioxidant effects of d-allose reduce brain edema in a water intoxication model of cytotoxic brain edema. Methods: Mice were injected intraperitoneally with distilled water (10 % of body weight) to create a model of brain edema. d-allose was administered orally at 400 mg/kg 30 min before the model was created. Two hours later, the degree of brain edema was measured by the dry-weight method to determine whether d-allose reduced brain edema. As an index of antioxidant effects, we measured changes over time in inflammatory cytokines (tumor necrosis factor-alpha, interleukin-6) induced by the water intoxication model, and whether d-allose reduced inflammatory cytokines 4 h after model creation. Results: Administration of d-allose significantly suppressed brain edema formation of the water-intoxication model. And it significantly reduced inflammatory cytokines (tumor necrosis factor-alpha, interleukin-6). These results suggest that the antioxidant effect of d-allose exerts an anti-inflammatory effect and reduces brain edema.

Low adsorption affinity of athabasca oil sands naphthenic acid fraction compounds to a peat-mineral mixture

Much of the toxicity in oil sands process-affected water in Athabasca oil sands tailings has been attributed to naphthenic acids (NAs) and associated naphthenic acid fraction compounds (NAFCs). Previous work has characterized the environmental behaviour and fate of these compounds, particularly in the context of constructed treatment wetlands. There is evidence that wetlands can attenuate NAFCs in natural and engineered contexts, but relative contributions of chemical, biotic, and physical adsorption with sequestration require deconvolution. In this work, the objective was to evaluate the extent to which prospective wetland substrate material may adsorb NAFCs using a peat-mineral mix (PMM) sourced from the Athabasca Oil Sands Region (AOSR). The PMM and NAFCs were first mixed and then equilibrated across a range of NAFC concentrations (5–500 mg/L) with moderate ionic strength and hardness (∼200 ppm combined Ca2+ and Mg2+) that approximate wetland water chemistry. Under these experimental conditions, low sorption of NAFCs to PMM was observed, where sorbed concentrations of NAFCs were approximately zero mg/kg at equilibrium. When NAFCs and PMM were mixed and equilibrated together at environmentally relevant concentrations, formula diversity increased more than could be explained by combining constituent spectra. The TOC present in this PMM was largely cellulose-derived, with low levels of thermally recalcitrant carbon (e.g., lignin, black carbon). The apparent enhancement of the concentration and diversity of components in PMM/NAFCs mixtures are likely related to aqueous solubility of some PMM-derived organic materials, as post-hoc combination of dissolved components from PMM and NAFCs cannot replicate enhanced complexity observed when the two components are agitated and equilibrated together.

Effects of cupric ions on the formation of chlorinated disinfection byproducts from nitrophenol compounds during UV/post-chlorination

Cupric ions (Cu2+) are ubiquitous in surface waters and can influence disinfection byproducts (DBPs) formation in water disinfection processes. This work explored the effects of Cu2+ on chlorinated DBPs (Cl-DBPs) formation from six representative nitrophenol compounds (NCs) during UV irradiation followed by a subsequent chlorination (i.e., UV/post-chlorination), and the results showed Cu2+ enhanced chlorinated halonitromethane (Cl-HNMs) formation from five NCs (besides 2-methyl-3-nitrophenol) and dichloroacetonitrile (DCAN) and trichloromethane (TCM) formation from six NCs. Nevertheless, excessive Cu2+ might reduce Cl-DBPs formation. Increasing UV fluences displayed different influences on total Cl-DBPs formation from different NCs, and increasing chlorine dosages and NCs concentrations enhanced that. Moreover, a relatively low pH (5.8) or high pH (7.8) might control the yields of total Cl-DBPs produced from different NCs. Notably, Cu2+ enhanced Cl-DBPs formation from NCs during UV/post-chlorination mainly through the catalytic effect on nitro-benzoquinone production and the conversion of Cl-DBPs from nitro-benzoquinone. Additionally, Cu2+ could increase the toxicity of total Cl-DBPs produced from five NCs besides 2-methyl-3-nitrophenol. Finally, the impacts of Cu2+ on Cl-DBPs formation and toxicity in real waters were quite different from those in simulated waters. This study is conducive to further understanding how Cu2+ affected Cl-DBPs formation and toxicity in chlorine disinfection processes and controlling Cl-DBPs formation in copper containing water.

Photocatalytic dye decomposition by bio-enzyme enriched TiO2/g-C3N4 nanocomposite and assessment of toxicity of resultant water using Catla catla fish

Nanocomposite of TiO2/g-C3N4 enriched with enzyme prepared from bio-wastes (fruit and vegetable peels) was synthesized for the photocatalytic decomposition of toxic dye solution and the toxicity, if any, of the resultant water obtained after treatment was tested by exposing freshwater Catla catla fish to the treated water. The result was compared with the toxicity of the untreated test dye solution. The bio-enzyme powered TiO2/g-C3N4 nanocomposite exhibits enhanced degradation efficiency of 99% for methylene blue (MB) and 95% for methyl orange (MO) in 45 min, whereas the bare TiO2/g-C3N4 exhibits efficiencies of only 92% for MB and 90% for MO. The quantitative study showed that enzymes present in the system viz., protease, peroxidase, cellulase, amylase and lipase act as supporting catalyst and thereby improve the photocatalytic ability of the synthesized nanocomposite for effective dye degradation. The results showed the combined effects of composite partners and the bio-cocatalyst. Characterization of the prepared samples was performed using XRD, FTIR, SEM, RAMAN, UV, EDS and XPS and the results are correlated with the application concerned. The histology study was performed through paraffin wax method to evaluate the toxic effects of the industrial dyes on Catla catla fish by exposing the fish to different aquarium systems (Dye, Control and Treated water).

Novel pH-sensitive triptolide-loaded micelles: a potential approach to increase anti-tumor activity of the diterpenoid epoxide

Tripterygium wilfordii Hook F, a traditional medicine in China has bioactive but toxic triptolide (TP, a diterpenoid triepoxide) as its main active constituents. The applications of TP are hampered by its prominent toxicity and low solubility in water. In this study, a safe pH-sensitive material [methoxy polyethylene glycol (mPEG)- adipic dihydrazide (ADH)] was synthesized and loaded with TP to form pH-sensitive polymeric micelles, thereby improving the safety and solubility of TP, as well as providing a theoretical basis for the wide application of TP. The mPEG-ADH/TP micelles were characterized by a series of indicators [namely entrapment efficiency (EE), critical micellar concentration (CMC), electrokinetic potential, stability, polydispersed index (PDI), and particle size]. Also, we ascertained the in vitro release of TP from mPEG-ADH/TP micelles along with pharmacokinetic investigations in vivo. Besides, we evaluated the cytotoxicity of mPEG-ADH/TP micelles against A549 cells, HCT116 cells, and HaCat cells and further conducted in vivo toxicity studies in rats. The TP-loaded mPEG-ADH micelles had smaller sized particles (48.3 nm), excellent PDI (0.142), stable property and higher EE (89.87%). Importantly, the TP in the mPEG-ADH/TP micelles was almost completely released at acidic pH (pH 5.0), while the drug was released slowly and sparingly at physiological pH (pH 7.4). The results suggest the release of TP from mPEG-ADH/TP micelles was sensitive to pH, which could facilitate targeting of the drug into intra-cellularly low pH endosomes and lysosomes as well as enhance cytotoxicity in cancer tissues. Moreover, mPEG-ADH/TP micelles exhibited excellent proliferation inhibition on tumor cells. In addition, the liver injury of rats in the 1 mg/kg dose of mPEG-ADH/TP micelles group was significantly reduced by Hematoxylin–eosin (HE) staining. Taken together, mPEG-ADH/TP micelles could act as a promising alternative to enhance the efficacy of oncologic treatments.

Impacts of Age and Gender on Brain Edema in a Mouse Water Intoxication Model.

Brain edema causes abnormal fluid retention and can be fatal in severe cases. Although it develops in various diseases, most treatments for brain edema are classical. We analyzed the impacts of age and gender on the characteristics of a water intoxication model that induces pure brain edema in mice and examined the model's usefulness for research regarding new treatments for brain edema. C57BL/6J mice received an intraperitoneal administration of 10% body weight distilled water, and we calculated the brain water content by measuring the brain-tissue weight immediately after dissection and after drying. We analyzed 8-OHdG and caspase-3 values to investigate the brain damage. We also applied this model in aquaporin 4 knockout (AQP4-) mice and compared these mice with wild-type mice. The changes in water content differed by age and gender, and the 8-OHdG and caspase-3 values differed by age. Suppression of brain edema by AQP4- was also confirmed. These results clarified the differences in the onset of brain edema by age and gender, highlighting the importance of considering the age and gender of model animals. Similar studies using genetically modified mice are also possible. Our findings indicate that this water intoxication model is effective for explorations of new brain edema treatments.

Synthesis and characterization of Ni@UiO-66 Metal-Organic Framework for fluorescence detection of heavy metal ions in the aqueous phase

The toxicity of clean fresh water has become a major concern in the 21st century. The pollution of fresh and marine water bodies via anthropogenic activities introduces fatal chemicals like heavy metal ions into the environment causing disastrous impacts on human life as well as floral-faunal biota. Hence, it is crucial to develop a nanomaterial that can probe on these lethal heavy metal ions feasibly as well as with low detection limits. Metal-Organic Frameworks are frequently employed in optics as fluorescence sensors for detecting heavy metal ions. Therefore, in this study, Ni(II) was doped into the UiO-66 network, and the fluorescent characteristics of the obtained MOF structure were observed. The morphological characterizations were conducted via PXRD and SEM while the optical tests based on fluorescent spectroscopy were given more attention. The as synthesized MOF i.e., Ni@UiO-66 gave excellent fluorescent detection exhibiting “Turn-Off” for Hg(II) and Fe(III), while “Turn On” for Cr(VI), and Al(III) analytes. In aqueous phase, the lowest detection limit values of 7.98 x 10−7 M for Hg(II) ions is observed. The former's sensing mechanism was attributed to the inner filter effect (IFE), while the latter's mechanism could potentially be linked to the chelation-enhanced fluorescent (CHEF) effect. These findings imply that the Ni@UiO-66 metal-organic framework has the potential to be used for the detection for minute quantities of Hg(II), Al(III), Cr(VI), and Fe(III) ions.