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1.
J Environ Manage ; 359: 120973, 2024 May.
Article in English | MEDLINE | ID: mdl-38703644

ABSTRACT

Chemical oxidation processes are widely used for the remediation of organically contaminated soils, but their potential impact on variable-valence and toxic metals such as chromium (Cr) is often overlooked. In this study, we investigated the risk of Cr(Ⅲ) oxidation in soils during the remediation of 2-chlorophenol (2-CP) contaminated soils using four different processes: Potassium permanganate (KMnO4), Modified Fenton (Fe2+/H2O2), Alkali-activated persulfate (S2O82-/OH-), and Fe2+-activated persulfate (S2O82-/Fe2+). Our results indicated that the KMnO4, Fe2+/H2O2, and S2O82-/Fe2+ processes progressively oxidized Cr(III) to Cr(Ⅵ) during the 2-CP degradation. The KMnO4 process likely involved direct electron transfer, while the Fe2+/H2O2 and S2O82-/Fe2+ processes primarily relied on HO• and/or SO4•- for the Cr(III) oxidation. Notably, after 4 h of 2-CP degradation, the Cr(VI) content in the KMnO4 process surpassed China's 3.0 mg kg-1 risk screening threshold for Class I construction sites, and further exceeded the 5.7 mg kg-1 limit for Class II construction sites after 8 h. Conversely, the S2O82-/OH- process exhibited negligible oxidation of Cr(III), maintaining a low oxidation ratio of 0.13%, as highly alkaline conditions induced Cr(III) precipitation, reducing its exposure to free radicals. Cr(III) oxidation ratio was directly proportional to oxidant dosage, whereas the Fe2+/H2O2 process showed a different trend, influenced by the concentration of reductants. This study provides insights into the selection and optimization of chemical oxidation processes for soil remediation, emphasizing the imperative for thorough risk evaluation of Cr(III) oxidation before their application.


Subject(s)
Chlorophenols , Chromium , Environmental Restoration and Remediation , Oxidation-Reduction , Soil Pollutants , Soil , Chromium/chemistry , Soil Pollutants/chemistry , Chlorophenols/chemistry , Soil/chemistry , Hydrogen Peroxide/chemistry , Potassium Permanganate/chemistry
2.
Chemosphere ; 358: 142249, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38705405

ABSTRACT

Chlorophenols (CPs) are a group of pollutants that pose a great threat to the environment, they are widely used in industrial and agricultural wastes, pesticides, herbicides, textiles, pharmaceuticals and plastics. Among CPs, pentachlorophenol was listed as one of the persistent organic pollutants (POPs) by the Stockholm convention. This study aims to identify the UDP-glucosyltransferase (UGT) isoforms involved in the metabolic elimination of CPs. CPs' mono-glucuronide was detected in the human liver microsomes (HLMs) incubation mixture with co-factor uridine-diphosphate glucuronic acid (UDPGA). HLMs-catalyzed glucuronidation metabolism reaction equations followed Michaelis-Menten or substrate inhibition type. Recombinant enzymes and chemical reagents inhibition experiments were utilized to phenotype the main UGT isoforms involved in the glucuronidation of CPs. UGT1A6 might be the major enzyme in the glucuronidation of mono-chlorophenol isomer. UGT1A1, UGT1A6, UGT1A9, UGT2B4 and UGT2B7 were the most important five UGT isoforms for metabolizing the di-chlorophenol and tri-chlorophenol isomers. UGT1A1 and UGT1A3 were the most important UGT isoforms in the catalysis of tetra-chlorophenol and pentachlorophenol isomers. Species differences were investigated using rat liver microsomes (RLMs), pig liver microsomes (PLMs), dog liver microsomes (DLMs), and monkey liver microsomes (MyLMs). All these results were helpful for elucidating the metabolic elimination and toxicity of CPs.


Subject(s)
Chlorophenols , Glucuronosyltransferase , Microsomes, Liver , Glucuronosyltransferase/metabolism , Chlorophenols/metabolism , Animals , Microsomes, Liver/metabolism , Humans , Rats , Environmental Pollutants/metabolism , Isoenzymes/metabolism , Glucuronides/metabolism
3.
J Colloid Interface Sci ; 669: 712-722, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38735253

ABSTRACT

The industrial applications of enzymes are usually hindered by the high production cost, intricate reusability, and low stability in terms of thermal, pH, salt, and storage. Therefore, the de novo design of nanozymes that possess the enzyme mimicking biocatalytic functions sheds new light on this field. Here, we propose a facile one-pot synthesis approach to construct Cu-chelated polydopamine nanozymes (PDA-Cu NPs) that can not only catalyze the chromogenic reaction of 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP), but also present enhanced photothermal catalytic degradation for typical textile dyes. Compared with natural laccase, the designed mimic has higher affinity to the substrate of 2,4-DP with Km of 0.13 mM. Interestingly, PDA-Cu nanoparticles are stable under extreme conditions (temperature, ionic strength, storage), are reusable for 6 cycles with 97 % activity, and exhibit superior substrate universality. Furthermore, PDA-Cu nanozymes show a remarkable acceleration of the catalytic degradation of dyes, malachite green (MG) and methylene blue (MB), under near-infrared (NIR) laser irradiation. These findings offer a promising paradigm on developing novel nanozymes for biomedicine, catalysis, and environmental engineering.


Subject(s)
Coloring Agents , Copper , Indoles , Laccase , Polymers , Copper/chemistry , Indoles/chemistry , Coloring Agents/chemistry , Laccase/chemistry , Laccase/metabolism , Catalysis , Polymers/chemistry , Particle Size , Surface Properties , Chlorophenols/chemistry , Chlorophenols/metabolism , Methylene Blue/chemistry , Methylene Blue/metabolism , Rosaniline Dyes
4.
J Hazard Mater ; 472: 134438, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38718504

ABSTRACT

Construction of an efficient bio-reductive dechlorination system remains challenging due to the narrow ecological niche and low-growth rate of organohalide-respiring bacteria during field remediation. In this study, a biochar-based organohalide-respiring bacterial agent was obtained, and its performance and effects on indigenous microbial composition, diversity, and inter-relationship in soil were investigated. A well-performing material, Triton X-100 modified biochar (BC600-TX100), was found to have the superior average pore size, specific surface area and hydrophicity, compared to other materials. Interestingly, Pseudomonas aeruginosa CP-1, which is capable of 2,4,6-TCP dechlorination, showed a 348 times higher colonization cell number on BC600-TX100 than that of BC600 after 7 d. Meanwhile, the dechlorination rate in soil showed the highest (0.732 d-1) in the BC600-TX100 bacterial agent than in the other agents. The long-term performance of the BC600-TX100 OHRB agent was also verified, with a stable dechlorination activity over six cycles. Soil microbial community analysis found the addition of the BC600-TX100 OHRB agent significantly increased the relative abundance of genus Pseudomonas from 1.53 % to 11.2 %, and Pseudomonas formed a close interaction relationship with indigenous microorganisms, creating a micro-ecological environment conducive to reductive dechlorination. This study provides a feasible bacterial agent for the in-situ bioremediation of soil contaminated organohalides. ENVIRONMENTAL IMPLICATION: Halogenated organic compounds are a type of toxic, refractory, and bio-accumulative persistent compounds widely existed in environment, widely detected in the air, water, and soil. In this study, we provide a feasible bacterial agent for the in-situ bioremediation of soil contaminated halogenated organic compounds. The application of biochar provides new insights for "Turning waste into treasure", which meets with the concept of green chemistry.


Subject(s)
Biodegradation, Environmental , Charcoal , Chlorophenols , Soil Microbiology , Soil Pollutants , Charcoal/chemistry , Soil Pollutants/metabolism , Soil Pollutants/chemistry , Chlorophenols/metabolism , Chlorophenols/chemistry , Halogenation , Pseudomonas aeruginosa/metabolism , Bacteria/metabolism
5.
Water Res ; 256: 121569, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38615604

ABSTRACT

Halogenated aromatic compounds possess bidirectional effects on denitrifying bio-electron behavior, providing electrons and potentially interfering with electron consumption. This study selected the typical 4-chlorophenol (4-CP, 0-100 mg/L) to explore its impact mechanism on glucose-supported denitrification. When COD(glucose)/COD(4-CP)=28.70-3.59, glucose metabolism remained the dominant electron supply process, although its removal efficiency decreased to 73.84-49.66 %. When COD(glucose)/COD(4-CP)=2.39-1.43, 4-CP changed microbial carbon metabolism priority by inhibiting the abundance of glucose metabolizing enzymes, gradually replacing glucose as the dominant electron donor. Moreover, 5-100 mg/L 4-CP reduced adenosine triphosphate (ATP) by 15.52-24.67 % and increased reactive oxygen species (ROS) by 31.13-63.47 %, causing severe lipid peroxidation, thus inhibiting the utilization efficiency of glucose. Activated by glucose, 4-CP dechlorination had stronger electron consumption ability than NO2--N reduction (NO3--N > 4-CP > NO2--N), combined with the decreased nirS and nirK genes abundance, resulting in NO2--N accumulation. Compared with the blank group (0 mg/L 4-CP), 5-40 mg/L and 60-100 mg/L 4-CP reduced the secretion of cytochrome c and flavin adenine dinucleotides (FAD), respectively, further decreasing the electron transfer activity of denitrification system. Micropruina, a genus that participated in denitrification based on glucose, was gradually replaced by Candidatus_Microthrix, a genus that possessed 4-CP degradation and denitrification functions after introducing 60-100 mg/L 4-CP.


Subject(s)
Denitrification , Electrons , Glucose , Glucose/metabolism , Chlorophenols/metabolism
6.
Lipids Health Dis ; 23(1): 126, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38685082

ABSTRACT

BACKGROUND: Overweight and obesity are among the leading chronic diseases worldwide. Environmental phenols have been renowned as endocrine disruptors that contribute to weight changes; however, the effects of exposure to mixed phenols on obesity are not well established. METHODS: Using data from adults in National Health and Nutrition Examination Survey, this study examined the individual and combined effects of four phenols on obesity. A combination of traditional logistic regression and two mixed models (weighted quantile sum (WQS) regression and Bayesian kernel-machine regression (BKMR)) were used together to assess the role of phenols in the development of obesity. The potential mediation of cholesterol on these effects was analyzed through a parallel mediation model. RESULTS: The results demonstrated that solitary phenols except triclosan were inversely associated with obesity (P-value < 0.05). The WQS index was also negatively correlated with general obesity (ß: 0.770, 95% CI: 0.644-0.919, P-value = 0.004) and abdominal obesity (ß: 0.781, 95% CI: 0.658-0.928, P-value = 0.004). Consistently, the BKMR model demonstrated the significant joint negative effects of phenols on obesity. The parallel mediation analysis revealed that high-density lipoprotein mediated the effects of all four single phenols on obesity, whereas low-density lipoprotein only mediated the association between benzophenol-3 and obesity. Moreover, Cholesterol acts as a mediator of the association between mixed phenols and obesity. Exposure to single and mixed phenols significantly and negatively correlated with obesity. Cholesterol mediated the association of single and mixed environmental phenols with obesity. CONCLUSIONS: Assessing the potential public health risks of mixed phenols helps to incorporate this information into practical health advice and guidance.


Subject(s)
Isoflavones , Obesity , Phenols , Humans , Phenols/urine , Male , Adult , Female , Middle Aged , Cholesterol/blood , Benzhydryl Compounds/urine , Triclosan/adverse effects , Nutrition Surveys , Bayes Theorem , Endocrine Disruptors/urine , Chlorophenols/urine
7.
Chemosphere ; 357: 142053, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38636917

ABSTRACT

Emerging organic contaminants present in the environment can be biodegraded in anodic biofilms of microbial fuel cells (MFCs). However, there is a notable gap existing in deducing the degradation mechanism, intermediate products, and the microbial communities involved in degradation of broad-spectrum antibiotic such as triclosan (TCS). Herein, the possible degradation of TCS is explored using TCS acclimatized biofilms in MFCs. 95% of 5 mgL-1 TCS are been biodegraded within 84 h with a chemical oxygen demand (COD) reduction of 62% in an acclimatized-MFC (A-MFC). The degradation of TCS resulted in 8 intermediate products including 2,4 -dichlorophenol which gets further mineralized within the system. Concurrently, the 16S rRNA V3-V4 sequencing revealed that there is a large shift in microbial communities after TCS acclimatization and MFC operation. Moreover, 30 dominant bacterial species (relative intensity >1%) are identified in the biofilm in which Sulfuricurvum kujiense, Halomonas phosphatis, Proteiniphilum acetatigens, and Azoarcus indigens significantly contribute to dihydroxylation, ring cleavage and dechlorination of TCS. Additionally, the MFC was able to produce 818 ± 20 mV voltage output with a maximum power density of 766.44 mWm-2. The antibacterial activity tests revealed that the biotoxicity of TCS drastically reduced in the MFC effluent, signifying the non-toxic nature of the degraded products. Hence, this work provides a proof-of-concept strategy for sustainable mitigation of TCS in wastewaters with enhanced bioelectricity generation.


Subject(s)
Bacteria , Biodegradation, Environmental , Bioelectric Energy Sources , Biofilms , Triclosan , Triclosan/metabolism , Bacteria/metabolism , Water Pollutants, Chemical/metabolism , RNA, Ribosomal, 16S , Chlorophenols/metabolism , Catalysis
8.
Ecotoxicol Environ Saf ; 277: 116345, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38653021

ABSTRACT

2,4-dichlorophenol (2,4-DCP), 2,5-DCP, 2,4,5-trichlorophenol (2,4,5-TCP), 2,4,6-TCP, and ortho-phenylphenol (OPP) are widely present in the environment. However, their associations with risk and prognosis of diabetes and prediabetes remains unclear. We investigated the associations of these five phenols with the risk of diabetes and prediabetes, and with all-cause and cardiovascular disease (CVD) mortality, in adults with diabetes or prediabetes (n=6419). Information on diabetes and prediabetes indicators, and mortality data was collected from the National Health and Nutrition Examination Survey. Logistic and Cox regression models were used to explore the associations of the five phenols with risk and prognosis of diabetes and prediabetes. Participants in the highest urinary 2,4-DCP and 2,5-DCP tertiles had higher odds of diabetes [adjusted odds ratio (aOR), 1.34, 95 % confidence interval (CI): 1.10, 1.62; aOR, 1.29, 95 % CI: 1.07, 1.56, respectively] than those in the lowest tertiles. Participants with urinary OPP concentrations above the limit of detection (LOD), but below median had an aOR of 1.25 (95 % CI: 1.08, 1.46) for prediabetes compared to those with concentrations below the LOD. In adults with diabetes, the highest 2,4-DCP and 2,5-DCP tertiles were associated with all-cause mortality [adjusted hazard ratio (aHR), 1.49; 95 % CI: 1.08, 2.06; aHR, 1.49; 95 % CI: 1.08, 2.05, respectively] and CVD mortality (aHR, 2.58; 95 % CI: 1.33, 4.97; aHR, 1.96; 95 % CI: 1.06, 3.60, respectively) compared with the lowest tertiles. Compared with 2,4,5-TCP concentrations below the LOD, those above median were associated with all-cause mortality (aHR: 1.75; 95 % CI: 1.24, 2.48) and CVD mortality (aHR: 2.34; 95 % CI: 1.19, 4.63) in adults with prediabetes. Furthermore, the associations between these phenols and mortality were strengthened in some subgroups. Environmental exposure to 2,4-DCP, 2,5-DCP, 2,4,5-TCP, and OPP increases the risk or adverse prognosis of diabetes or prediabetes in adults in the US. Further studies are required to confirm these findings.


Subject(s)
Chlorophenols , Diabetes Mellitus , Environmental Pollutants , Prediabetic State , Humans , Chlorophenols/urine , Male , Prediabetic State/urine , Prediabetic State/epidemiology , Prediabetic State/chemically induced , Female , Middle Aged , Diabetes Mellitus/epidemiology , Adult , Environmental Pollutants/urine , Phenols/urine , Prognosis , Nutrition Surveys , Aged , Cardiovascular Diseases/mortality , Cardiovascular Diseases/epidemiology , Environmental Exposure/statistics & numerical data , Environmental Exposure/adverse effects
9.
Chemosphere ; 356: 141857, 2024 May.
Article in English | MEDLINE | ID: mdl-38570045

ABSTRACT

Palladized iron (Pd/Fe) represents one of the most common modification strategies for nanoscale zero-valent iron (nZVI). Most studies prepared Pd/Fe by reducing iron salts and depositing Pd species on the surface of pre-synthesized nZVI, which can be called the two-step method. In this study, we proposed a one-step method to obtain Pd/Fe by the concurrent formation of Fe0 and Pd0 and investigated the effects of these two methods on 4-chlorophenol (4-CP) removal, with carboxymethylcellulose (CMC) coated as a surface modifier. Results indicated that the one-step method, not only streamlined the synthesis process, but also Pd/Fe-CMCone-step, synthesized by it, exhibited a higher 4-CP removal rate (97.9%) compared to the two-step method material Pd/Fe-CMCtwo-step (82.4%). Electrochemical analyses revealed that the enhanced activity of Pd/Fe-CMCone-step was attributed to its higher electron transfer efficiency and more available reactive species, active adsorbed hydrogen species (Hads*). Detection of intermediate products demonstrated that, under the influence of Pd/Fe-CMCone-step, the main route of 4-CP was through hydrodechlorination (HDC) to form phenol and H* was the main active specie, supported by EPR tests, quenching experiments and product analysis. Additionally, the effects of initial 4-CP concentration, initial pH, O2 concentration, anions such as Cl-, SO42-, HCO3-, and humic acid (HA) were also investigated. In conclusion, the results of this study suggest that Pd/Fe-CMCone-step, synthesized through the one-step method, is a convenient and efficient nZVI-modifying material suitable for the HDC of chlorinated organic compounds.


Subject(s)
Carboxymethylcellulose Sodium , Chlorophenols , Iron , Palladium , Chlorophenols/chemistry , Carboxymethylcellulose Sodium/chemistry , Iron/chemistry , Palladium/chemistry , Water Pollutants, Chemical/chemistry , Halogenation , Adsorption , Metal Nanoparticles/chemistry , Suspensions
10.
Seizure ; 118: 80-90, 2024 May.
Article in English | MEDLINE | ID: mdl-38643679

ABSTRACT

PURPOSE: To compare the efficacy, safety, and tolerability of cenobamate with other newer anti-seizure medications (ASMs) including brivaracetam, eslicarbazepine, lacosamide, perampanel, and zonisamide, approved for adjunctive treatment of drug-resistant focal-onset seizures (FOS) in adults with epilepsy. METHODS: A systematic literature review (SLR) was conducted to obtain relevant efficacy, safety, and tolerability data for ASMs for the treatment of drug-resistant FOS. All studies were thoroughly assessed for potential sources of heterogeneity and analysed via Bayesian network meta-analyses (NMAs). Efficacy outcomes were ≥50 % responder rate and seizure freedom during the maintenance period, which were modelled simultaneously using a multinomial Bayesian NMA. Safety and tolerability outcomes were the proportion of patients who experienced at least one treatment-emergent adverse event (TEAE) and the proportion who experienced at least one TEAE leading to discontinuation. RESULTS: The SLR identified 76 studies, of which 23 were included in the Bayesian NMAs. Cenobamate was associated with statistically significant higher rates for the ≥50 % responder rate and seizure freedom outcomes compared with all ASMs analysed. The point estimates indicated that cenobamate was associated with higher rates of experiencing at least one TEAE and at least one TEAE leading to discontinuation compared with brivaracetam, lacosamide, and zonisamide; however, no results were statistically significant. CONCLUSION: Cenobamate was associated with increased efficacy compared with all ASMs analysed. There were no statistically significant differences in the safety and tolerability outcomes. The results presented corroborate the conclusions drawn from previous published NMAs, which also highlight the notable efficacy of cenobamate in comparison with other ASMs.


Subject(s)
Anticonvulsants , Network Meta-Analysis , Humans , Anticonvulsants/therapeutic use , Anticonvulsants/administration & dosage , Seizures/drug therapy , Carbamates/therapeutic use , Carbamates/administration & dosage , Epilepsies, Partial/drug therapy , Chlorophenols/therapeutic use , Chlorophenols/adverse effects , Chlorophenols/administration & dosage , Tetrazoles
11.
Seizure ; 118: 95-102, 2024 May.
Article in English | MEDLINE | ID: mdl-38652999

ABSTRACT

INTRODUCTION: Adjunctive cenobamate was effective and safe for the treatment of uncontrolled focal onset seizures in a randomized, double-blind, placebo-controlled, phase 2 study (YKP3089C017; NCT01866111). This post-hoc analysis assessed the efficacy of adjunctive cenobamate in the treatment of patients with different epileptic etiologies during the study. METHODS: Adult patients with uncontrolled focal seizures who previously received 1 to 3 antiseizure medications (ASMs) were randomly assigned in a ratio of 1:1:1:1 to receive placebo or cenobamate 100, 200 or 400 mg/day. Patients were further stratified based on their etiologic causes as genetic/presumed genetic, unknown cause, structural cause, and not reported (NR) groups. The frequency per 28 days for an 18-week double-blind treatment period, responder rates (≥50 %, ≥75 %, ≥90 %, and 100 %) during the maintenance phase (12 weeks), and safety were assessed. RESULTS: A total of 394 patients were categorized into the genetic/presumed genetic (n = 9; 2.28 %), unknown cause (n = 199; 50.51 %), structural cause (n = 177; 44.92 %), and NR (n = 13; 3.30 %) groups, with 4 patients were classified into either of the two etiological causes each. The baseline characteristics were comparable. The percentage of reduction in seizure frequency per 28 days was significantly higher in the cenobamate-treated structural (p = 0.01) and unknown cause (p = 0.0003) groups compared with the placebo group. Responder rates of ≥50 %, ≥75 %, ≥90 %, and 100 % were also higher with cenobamate therapy. Notably, no serious treatment-emergent adverse events (TEAEs) were observed in the genetic/presumed genetic group treated with cenobamate. The most common TEAEs (≥10 %) occurring in patients treated with cenobamate were nervous system disorders by system organ class, and somnolence was the most commonly reported TEAE. CONCLUSION: Cenobamate reduces seizures in adult patients previously treated with ASMs, with high responder rates and acceptable safety, regardless of underlying causes.


Subject(s)
Anticonvulsants , Carbamates , Chlorophenols , Humans , Double-Blind Method , Male , Anticonvulsants/therapeutic use , Female , Carbamates/therapeutic use , Carbamates/adverse effects , Adult , Middle Aged , Chlorophenols/adverse effects , Chlorophenols/therapeutic use , Chlorophenols/pharmacology , Chlorophenols/administration & dosage , Drug Therapy, Combination , Young Adult , Treatment Outcome , Seizures/drug therapy , Aged , Adolescent , Tetrazoles
12.
Chemosphere ; 357: 142116, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38663674

ABSTRACT

This study explores the utilization of semiconductor-based photocatalysts for environmental remediation through photocatalytic degradation, harnessing solar energy for effective treatment. The primary focus is on the application of photocatalytic technology for the degradation of 2-chlorophenol and methylene blue, critical pollutants requiring remediation. The research involves the synthesis of binary AgAlO2/g-C3N4 nanocomposites through an exchange ion method, subsequent calcination, and sonication. This process enhances the transfer of photogenerated electrons from AgAlO2 to g-C3N4, resulting in a significantly increased reductive electron charge on the surface of g-C3N4. The photocatalytic activity of the synthesized composites is comprehensively examined in the degradation of 2-chlorophenol and methylene blue through detailed crystallographic, electron-microscopy, photoemission spectroscopy, electrochemical, and spectroscopic characterizations. Among the various composites, AgAlO2/20% g-C3N4 emerges as the most active photocatalyst, achieving an impressive 98% degradation of methylene blue and 97% degradation of 2-chlorophenol under visible light. Notably, AgAlO2/20% g-C3N4 surpasses bare AgAlO2 and bare g-C3N4, exhibiting 1.66 times greater methylene blue degradation and constant rate (k) values of 20.17 × 10-3 min-1, 4.18 × 10-3 min-1 and 3.48 × 10-3 min-1, respectively. The heightened photocatalytic activity is attributed to the diminished recombination rate of electron-hole pairs. Scavenging evaluations confirm that O2•- and h+ are the primary photoactive species steering methylene blue photodegradation over AgAlO2/g-C3N4 in the visible region. These findings present new possibilities for the development of efficient binary photocatalysts for environmental remediation.


Subject(s)
Chlorophenols , Environmental Pollutants , Environmental Restoration and Remediation , Light , Methylene Blue , Environmental Restoration and Remediation/methods , Chlorophenols/chemistry , Catalysis , Environmental Pollutants/chemistry , Methylene Blue/chemistry , Nanocomposites/chemistry , Photolysis
13.
J Toxicol Environ Health A ; 87(11): 480-495, 2024 Jun 02.
Article in English | MEDLINE | ID: mdl-38591921

ABSTRACT

The toxic effects of 2, 4-dichlorophenol (2, 4-DCP) on aquatic organisms are well-established; however, the details regarding the mechanisms underlying the toxicity, especially immunotoxicity are poorly understood. Consequently, the aim of this study was to investigate the histopathologic, oxidative stress and immunotoxic effects attributed to exposure to sublethal concentrations of 2,4-DCP in the African catfish, Clarias gariepinus. Juvenile C. gariepinus were exposed to 0.4, 0.8, or 1.6 mg/L 2, 4-DCP for 28 days after which blood and head kidney were extracted for the determination of various nonspecific innate immune parameters while the liver was excised for histopathology examination and measurement of oxidative stress biomarkers. Control fish were maintained in water spiked 10 µL/L ethanol, representing the solvent control. A significant increase was noted in the activities of lactate dehydrogenase and superoxide dismutase as well as in levels of lipid peroxidation and DNA fragmentation in a dose-dependent manner, with higher adverse effects observed at the highest concentration tested (1.6 mg/L). The total white blood cells (WBC) count was significantly elevated in fish exposed to 2,4-DCP compared to control. Myeloperoxidase content was decreased significantly in fish exposed to 2,4-DCP especially at the highest concentration (1.6 mg/L) compared to controls. The respiratory burst activity did not differ markedly amongst groups. Histopathological lesions noted included edema, leucocyte infiltration, and depletion of hemopoietic tissue in the head kidney of exposed fish. There was significant upregulation in the mRNA expression of tumor necrosis factor (TNF-α) and heat shock protein 70 (HSP 70) but downregulation of major histocompatibility complex 2 (MHC 2) in exposed fish. Data demonstrated that exposure to 2,4-DCP resulted in histopathological lesions, oxidative stress, and compromised immune system in C. gariepinus.


Subject(s)
Catfishes , Chlorophenols , Water Pollutants, Chemical , Animals , Catfishes/metabolism , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/metabolism , Oxidative Stress , Lipid Peroxidation , Immunity, Innate
14.
Sci Rep ; 14(1): 6457, 2024 03 18.
Article in English | MEDLINE | ID: mdl-38499640

ABSTRACT

Our study aimed to evaluate the correlation between levels of 2,4-DCP(2,4-Dichlorophenol) and 2,5-DCP(2,5-Dichlorophenol) and the prevalence of kidney stones in US female adults. Participants were chosen from the National Health and Nutrition Examination Survey database, spanning the years 2007-2016. Dose-response curves were analyzed using logistic regression, subgroup analyses, and other statistical methods to evaluate the relationship between 2,4-DCP and 2,5-DCP levels and the prevalence of kidney stones. The final study included 3220 participants aged over 20 years, with 252 females reporting a history of kidney stones. After accounting for all interfering variables, we found that every 0.1 ug/ml increase in 2.4-DCP correlated with a 1% rise in kidney stone prevalence (OR = 1.01, 95% CI 1.00, 1.01), whereas the same increase in 2.5-DCP was linked to a 27% growth in prevalence (OR = 1.27, 95% CI 1.01, 1.61). Sensitivity analysis was performed by triangulating 2,4-DCP and 2,5-DCP levels. The dose-response curves demonstrated a linear positive relationship between 2,4-DCP and 2,5-DCP levels and the risk of stone development. Our findings indicate a positive correlation between 2,4-DCP and 2,5-DCP levels and the prevalence of kidney stones in US female adults. This association is of clinical significance; however, a direct causal relationship cannot be definitively established.


Subject(s)
Chlorophenols , Kidney Calculi , Adult , Humans , Female , Nutrition Surveys , Prevalence , Kidney Calculi/epidemiology , Kidney Calculi/etiology , Phenols
15.
Sci Total Environ ; 922: 171270, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38428603

ABSTRACT

Although triclosan has been ubiquitously detected in aquatic environment and is known to have various adverse effects to fish, details on its uptake, bioconcentration, and elimination in fish tissues are still limited. This study investigated the uptake and elimination toxicokinetics, bioconcentration, and biotransformation potential of triclosan in Nile tilapia (Oreochromis niloticus) exposed to environmentally-relevant concentrations under semi-static regimes for 7 days. For toxicokinetics, triclosan reached a plateau concentration within 5-days of exposure, and decreased to stable concentration within 5 days of elimination. Approximately 50 % of triclosan was excreted by fish through feces, and up to 29 % of triclosan was excreted through the biliary excretion. For fish exposed to 200 ng·L-1, 2000 ng·L-1, and 20,000 ng·L-1, the bioconcentration factors (log BCFs) of triclosan in fish tissues obeyed similar order: bile ≈ intestine > gonad ≈ stomach > liver > kidney ≈ gill > skin ≈ plasma > brain > muscle. The log BCFs of triclosan in fish tissues are approximately maintained constants, no matter what triclosan concentrations in exposure water. Seven biotransformation products of triclosan, involved in both phase I and phase II metabolism, were identified in this study, which were produced through hydroxylation, bond cleavages, dichlorination, and sulfation pathways. Metabolite of triclosan-O-sulfate was detected in all tissues of tilapia, and more toxic product of 2,4-dichlorophenol was also found in intestine, gonad, and bile of tilapia. Meanwhile, two metabolites of 2,4-dichlorophenol-O-sulfate and monohydroxy-triclosan-O-sulfate were firstly discovered in the skin, liver, gill, intestine, gonad, and bile of tilapia in this study. These findings highlight the importance of considering triclosan biotransformation products in ecological assessment. They also provide a scientific basis for health risk evaluation of triclosan to humans, who are associated with dietary exposure through ingesting fish.


Subject(s)
Chlorophenols , Cichlids , Tilapia , Triclosan , Water Pollutants, Chemical , Animals , Humans , Tilapia/metabolism , Triclosan/toxicity , Triclosan/metabolism , Tissue Distribution , Cichlids/metabolism , Biotransformation , Sulfates/metabolism , Water Pollutants, Chemical/analysis
16.
Drugs Aging ; 41(3): 251-260, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38446341

ABSTRACT

BACKGROUND: Cenobamate is an antiseizure medication (ASM) approved in the US and Europe for the treatment of uncontrolled focal seizures. OBJECTIVE: This post hoc analysis of a phase III, open-label safety study assessed the safety and efficacy of adjunctive cenobamate in older adults versus the overall study population. METHODS: Adults aged 18-70 years with uncontrolled focal seizures taking stable doses of one to three ASMs were enrolled in the phase III, open-label safety study; adults aged 65-70 years from that study were included in our safety analysis. Discontinuations due to adverse events and treatment-emergent adverse events (TEAEs) were assessed throughout the study in all patients who received one or more doses of cenobamate (safety study population). Efficacy was assessed post hoc in patients who had adequate seizure data available (post hoc efficacy population); we assessed patients aged 65-70 years from that population. Overall, 100% responder rates were assessed in the post hoc efficacy maintenance-phase population in 3-month intervals. Concomitant ASM drug load changes were also measured. For each ASM, drug load was defined as the ratio of actual drug dose/day to the World Health Organization defined daily dose (DDD). RESULTS: Of 1340 patients (mean age 39.7 years) in the safety study population, 42 were ≥ 65 years of age (mean age 67.0 years, 52.4% female). Median duration of exposure was 36.1 and 36.9 months for overall patients and older patients, respectively, and mean epilepsy duration was 22.9 and 38.5 years, respectively. At 1, 2, and 3 years, 80%, 72%, and 68% of patients overall, and 76%, 71%, and 69% of older patients, respectively, remained on cenobamate. Common TEAEs (≥ 20%) were somnolence and dizziness in overall patients, and somnolence, dizziness, fall, fatigue, balance disorder, and upper respiratory tract infection in older patients. Falls in older patients occurred after a mean 452.1 days of adjunctive cenobamate treatment (mean dose 262.5 mg/day; mean concomitant ASM drug load 2.46). Of 240 patients in the post hoc efficacy population, 18 were ≥ 65 years of age. Mean seizure frequency at baseline was 18.1 seizures/28 days for the efficacy population and 3.1 seizures/28 days for older patients. Rates of 100% seizure reduction within 3-month intervals during the maintenance phase increased over time for the overall population (n = 214) and older adults (n = 15), reaching 51.9% and 78.6%, respectively, by 24 months. Mean percentage change in concomitant ASM drug load, not including cenobamate, was reduced in the overall efficacy population (31.8%) and older patients (36.3%) after 24 months of treatment. CONCLUSIONS: Results from this post hoc analysis showed notable rates of efficacy in older patients taking adjunctive cenobamate. Rates of several individual TEAEs occurred more frequently in older patients. Further reductions in concomitant ASMs may be needed in older patients when starting cenobamate to avoid adverse effects such as somnolence, dizziness, and falls. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov NCT02535091.


Subject(s)
Anticonvulsants , Carbamates , Chlorophenols , Dizziness , Tetrazoles , Humans , Female , Aged , Male , Anticonvulsants/adverse effects , Dizziness/chemically induced , Dizziness/drug therapy , Sleepiness , Treatment Outcome , Drug Therapy, Combination , Double-Blind Method , Seizures/drug therapy
17.
Food Chem ; 447: 138968, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-38489877

ABSTRACT

Given the severe problem of Baijiu authenticity, it is essential to discriminate Baijiu from different origins quickly and effectively. As organic acids (OAs) are the most dominant taste-imparting substances in Baijiu, we proposed a simple, fast, and effective OAs-targeted colorimetric sensor array based on the colorimetric reaction of 4-aminophenol (AP)/4-amino-3-chlorophenol (ACP) under oxidation of Cu(NO3)2 for the rapid discrimination of origins of Baijiu with three main aroma types. Hydrogen ions ionized from OAs induced the protonation of the amino group, which blocked the colorimetric reaction, and the different levels of OAs in Baijiu enabled the array to discriminate different origins of Baijiu. The array was implemented to analyze 10 simple OAs and 16 mixed OAs and further for the discrimination of 42 Baijius with an accuracy of 98%. This method provided an efficient research strategy for a basis for rapid quality analysis of Baijiu.


Subject(s)
Chlorophenols , Odorants , Volatile Organic Compounds , Odorants/analysis , Colorimetry , Gas Chromatography-Mass Spectrometry/methods , Volatile Organic Compounds/analysis , Acids/analysis
19.
J Hazard Mater ; 469: 133983, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38471376

ABSTRACT

The transient chlorophenol shock under some emergency conditions might directly affect the pollutant removal of bioreactor. Therefore, the recovery of bioreactor performance after transient chlorophenol shock is a noteworthy issue. In the present research, the performance, antioxidant response, microbial succession and functional genes of sequencing batch reactor (SBR) were evaluated under transient 2,4,6-trichlorophenol (2,4,6-TCP) shock. The chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) removal efficiencies decreased sharply in the first 4 days after 60 mg/L 2,4,6-TCP shock for 24 h and gradually recovered to normal in the subsequent 8 days. The nitrogen removal rates and their corresponding enzymatic activities rapidly decreased after transient 2,4,6-TCP shock and then gradually increased to normal. The increase of antioxidant enzymatic activity, Cu-Zn SOD genes and Fe-Mn SOD genes contributed to the recovery of SBR performance. The abundance of genes encoding ammonia monooxygenase and hydroxylamine dehydrogenase decreased after transient 2,4,6-TCP shock, including amoA, amoC and nxrA. Thauera, Dechloromonas and Candidatus_Competibacter played key roles in the restorative process, which provided stable abundances of narG, norB , norC and nosZ. The results will deeply understand into the effect of transient 2,4,6-TCP shock on bioreactor performance and provide theoretical basis to build promising recoveries strategy of bioreactor performance.


Subject(s)
Antioxidants , Chlorophenols , Bioreactors , Nitrogen , Sewage , Waste Disposal, Fluid
20.
Chirality ; 36(4): e23660, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38511944

ABSTRACT

A green and efficient process for the synthesis of cenobamate has been accomplished in 70% yield and >99% ee through the bio-reduction of ß-ketotetrazole using Daucus carota whole plant cells. The corresponding ß-hydroxytetrazole was isolated in 60% yield and >98% ee. This is the first report on the biocatalytic reduction of ß-ketotetrazole using plant enzymes derived from D. carota root cells with excellent enantioselectivity.


Subject(s)
Anticonvulsants , Carbamates , Chlorophenols , Ketones , Tetrazoles , Stereoisomerism , Biocatalysis
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