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1.
Environ Sci Technol ; 57(39): 14515-14525, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37728733

RESUMO

The hepatotoxicities of perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been extensively investigated, while little is known about the sex-specific differences. In this study, common carp were exposed to the emerging perfluoroalkyl phosphinic acids (6:6 and 8:8 PFPiAs) for 14 days to disclose sex-specific hepatotoxicity. Apparent hepatotoxicity, including cell necrosis, apoptosis, and steatosis, was observed in both male and female carp liver. The observed hepatocyte steatosis was predominantly attributed to the dysregulation of hepatic lipid metabolism but was based on sex-specific mechanisms. It was manifested as inhibited oxidative decomposition of fatty acids (FAs) in the female liver, whereas it enhanced the uptake of FAs into the male liver, both of which led to excessive lipid accumulation. Untargeted lipidomics validated that the metabolism pathways of FA, sphingolipid, glycerolipid, and glycerophospholipid were disrupted by both compounds, leading to the generation of reactive oxygen species and oxidative stress. The oxidative stress further evolved into inflammation, manifested as promoted expression of proinflammatory cytokines and repressed expression of anti-inflammatory cytokines. Consistently, all of the changes were more noticeable in male carp, suggesting that male fish were more susceptible to PFPiA disruption. 8:8 PFPiA was less accumulated but caused stronger hepatotoxicity than 6:6 PFPiA, possibly because of the stronger binding capacity of 8:8 PFPiA to nuclear transcription factors mediating lipid metabolism and inflammation. The findings of this study highlight the significance of sex- and chemical-dependent bioaccumulation and the toxicity of PFASs in organisms.


Assuntos
Carpas , Doença Hepática Induzida por Substâncias e Drogas , Fluorocarbonos , Poluentes Químicos da Água , Masculino , Animais , Feminino , Ácidos Fosfínicos , Carpas/metabolismo , Citocinas , Inflamação , Fluorocarbonos/toxicidade , Poluentes Químicos da Água/metabolismo
2.
Eur J Med Chem ; 257: 115528, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37290184

RESUMO

Catechols have been reported to be potent covalent inhibitors of ureases, and they exhibit activity by modifying cysteine residues at the entrance to enzymatic active sites. Following these principles, we designed and synthesized novel catecholic derivatives that contained carboxylate and phosphonic/phosphinic functionalities and assumed expanded specific interactions. When studying the chemical stability of the molecules, we found that their intrinsic acidity catalyzes spontaneous esterification/hydrolysis reactions in methanol or water solutions, respectively. Regarding biological activity, the most promising compound, 2-(3,4-dihydroxyphenyl)-3-phosphonopropionic acid (15), exhibited significant anti-urease potential (Ki = 2.36 µM, Sporosarcinia pasteurii urease), which was reflected in the antiureolytic effect in live Helicobacter pylori cells at a submicromolar concentration (IC50 = 0.75 µM). As illustrated by molecular modeling, this compound was bound in the active site of urease through a set of concerted electrostatic and hydrogen bond interactions. The antiureolytic activity of catecholic phosphonic acids could be specific because these compounds were chemically inert and not cytotoxic to eukaryotic cells.


Assuntos
Helicobacter pylori , Ácidos Fosfínicos/farmacologia , Urease , Modelos Moleculares , Catecóis/farmacologia , Catecóis/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química
3.
J Hazard Mater ; 448: 130896, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36764254

RESUMO

As alternatives of long-chain PFASs (Poly- and perfluoroalkyl substances), perfluoroalkyl phosphinic acids (PFPiAs) are increasingly observed in the environment, but their environmental behaviors have not been well understood. Here, the microbial biotransformation of C6/C6 and C8/C8 PFPiA in two soils (Soil N and Y) was investigated. After 252 d and 330 d of incubation with PFPiAs in Soil N and Y respectively, the levels of PFPiAs decreased distinctly, accompanied by the increasing perfluorohexaphosphonic acid (PFHxPA) or perfluorooctanophosphonic acid (PFOPA) formation, magnifying PFPiAs were susceptible to C-P cleavage, which was also confirmed by the density functional theory calculations. The half-lives of the PFPiAs were longer than one year, while generally shorter in Soil N than in Soil Y and that of C6/C6 was shorter than C8/C8 PFPiA (392 d and 746 d in Soil N, and 603 and 1155 d in Soil Y, respectively). Metagenomic sequencing analysis revealed that Proteobacteria as the primary host of the potential functional genes related to CP bond cleavage might be the crucial phyla contributing to the biotransformation of PFPiAs. Meanwhile, the more intensive interactions between the microbes in Soil N consistently contribute to its greater capacity for transforming PFPiAs.


Assuntos
Fluorocarbonos , Ácidos Fosfínicos , Ácidos Fosfínicos/metabolismo , Solo , Meia-Vida , Biotransformação , Fluorocarbonos/análise
4.
Macromol Rapid Commun ; 44(9): e2200921, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36603223

RESUMO

Placement of phosphorus in the polymer main chain leads to organophosphorus polymers with potentially unique chemical and physical properties. Herein, it is demonstrated that the Abramov phosphonylation reaction can be extended to the synthesis of such polymers, by reacting di- or tricarbaldehydes with phosphinic acid (PA) in the presence of N,O-bis(trimethylsilyl)acetamide (BSA). This technique affords polymers with main chain PC bonds, wherein phosphorus (V), aromatic rings, and hydroxymethylene moieties are linked by bis(α-hydroxymethylene)phosphinic acid (BHMPA) units. The resulting polymers are water soluble, display resilience against acid- and base-catalyzed hydrolysis, and exhibit superior thermal stability with high char yield in air (≈83%) and nitrogen (≈76%) atmosphere.


Assuntos
Ácidos Fosfínicos , Polímeros , Polímeros/química , Água/química , Ácidos , Fósforo
5.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36675149

RESUMO

Macromolecules containing acidic fragments in side-groups­polyacids­occupy a special place among synthetic polymers. Properties and applications of polyacids are directly related to the chemical structure of macromolecules: the nature of the acidic groups, polymer backbone, and spacers between the main chain and acidic groups. The chemical nature of the phosphorus results in the diversity of acidic >P(O)OH fragments in sidechain phosphorus-containing polyacids (PCPAs) that can be derivatives of phosphoric or phosphinic acids. Sidechain PCPAs have many similarities with other polyacids. However, due to the relatively high acidity of −P(O)(OH)2 fragment, bone and mineral affinity, and biocompatibility, sidechain PCPAs have immense potential for diverse applications. Synthetic approaches to sidechain PCPAs also have their own specifics. All these issues are discussed in the present review.


Assuntos
Fósforo , Polímeros , Polímeros/química , Ácidos , Substâncias Macromoleculares , Ácidos Fosfínicos/química
6.
Environ Sci Pollut Res Int ; 30(11): 31408-31420, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36447100

RESUMO

In this study, phosphorylated polyacrylonitrile hollow fiber membrane was synthesized by reacting aminated polyacrylonitrile hollow fiber membrane with phosphinic acid in a Mannich reaction. The batch single-factor measurements revealed that the phosphorylated polyacrylonitrile (PPAN) membrane had an outstanding ability for Hg2+ adsorption. Thermodynamic investigations indicated that the adsorption process was homogenous, and the theoretical maximum adsorption capacity predicted by the Langmuir model was 371.75 mg·g-1. The PPAN membrane was able to successfully chelate Hg2+ ions and attain saturation in 4 h, demonstrating that the reaction was chemically controlled by the adsorption kinetics. Based on the FT-IR and XPS spectral characterization data, successful phosphinic acid group grafting was proven, and a plausible mechanism for Hg2+ adsorption by PPAN membranes was presented. Furthermore, the five adsorption-desorption cycle experiments revealed that PPAN hollow fiber membranes had outstanding reusability, indicating a possible use for removing heavy metal ions from wastewater.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Ácidos Fosfínicos , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Íons , Cinética , Poluentes Químicos da Água/análise
7.
Int J Mol Sci ; 23(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36293470

RESUMO

The adsorption properties of two coordination polymers, resulting from the reaction of divalent metal (Ca2+ or Co2+) salts with (2-carboxyethyl)(phenyl)phosphinic acid, are presented in this paper. The structural and textural characterization before and after adsorption experiments is presented. The adsorbent materials were prepared using the hydrothermal procedure. The compound Ca[O2P(CH2CH2COOH)(C6H5)]2 (CaCEPPA) has a layered topology, with the phenyl groups oriented into the interlayer space and crystallizes in the monoclinic system. Compound Co2[(O2P(CH2CH2COO)(C6H5)(H2O)]2·2H2O (CoCEPPA) has a 1D structure composed of zig-zag chains. The adsorption performances of CaCEPPA and CoCEPPA materials were tested in the removal of cadmium and lead from aqueous solutions. The optimum pH of ions adsorption was found to be five for both adsorbent materials. Pseudo-first and second-order kinetic models were used for fitting kinetic experimental data, and Langmuir and Freundlich isotherms were used for modeling the equilibrium experimental data. The pseudo-second-order kinetic model and Langmuir isotherm best described the adsorption of Cd and Pb ions onto the studied materials, judging from the results of the error function (correlation coefficient, sum of square error, chi-square test, and average relative error) analysis. The studied materials present a higher affinity for Cd ions compared with the adsorption capacity developed for the removal of Pb ions from aqueous solutions. CoCEPPA showed the highest adsorption performance in the removal process of metal ions from aqueous solutions compared with CaCEPPA (qm = 54.9 mg Cd2+/g of CoCEPPA, qm = 36.5 mg Cd2+/g of CaCEPPA).


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Águas Residuárias/química , Cádmio/química , Poluentes Químicos da Água/química , Ácidos Fosfínicos , Sais , Dióxido de Carbono , Chumbo , Concentração de Íons de Hidrogênio , Adsorção , Íons , Cinética , Água , Polímeros
8.
Molecules ; 27(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35956755

RESUMO

The purpose of this study was to optimize the extraction conditions for separating Co2+ from Ni2+ using N-butylamine phosphinate ionic liquid of [C4H9NH3][Cyanex 272]. A Box-Behnken design of response surface methodology was used to analyze the effects of the initial pH, extraction time, and extraction temperature on the separation factor of Co2+ from sulfuric acid solution containing Ni2+. The concentrations of Co2+ and Ni2+ in an aqueous solution were determined using inductively coupled plasma-optical emission spectrometry. The optimized extraction conditions were as follows: an initial pH of 3.7, an extraction time of 55.8 min, and an extraction temperature of 330.4 K. The separation factor of Co2+ from Ni2+ under optimized extraction conditions was 66.1, which was very close to the predicted value of 67.2, and the error was 1.7%. The equation for single-stage extraction with high reliability can be used for optimizing the multi-stage extraction process of Co2+ from Ni2+. The stoichiometry of chemical reaction for ion-exchange extraction was also investigated using the slope method.


Assuntos
Líquidos Iônicos , Concentração de Íons de Hidrogênio , Líquidos Iônicos/química , Ácidos Fosfínicos/química , Reprodutibilidade dos Testes
11.
Eur Urol ; 82(5): 501-509, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690515

RESUMO

BACKGROUND: Fluorine-18 (18F)-labelled prostate-specific membrane antigen (PSMA) offers several advantages over gallium-68 (68Ga) in terms of costs, yield, transport/distribution, and image resolution. OBJECTIVE: This trial investigates the new radiotracer 18F-PSMA-11 via a prospective, intraindividual crossover design. The trial was powered for noninferiority of 18F-PSMA-11 over 68Ga-PSMA-11 positron emission tomography (PET)/computed tomography (CT) in terms of the number of positive PET scans. Secondary endpoints were as follows: (1) superiority of 18F-PSMA-11 over 68Ga-PSMA-11 with respect to the number of positive PET scans, the total number of suspicious prostate cancer lesions, and the miPSMA expression score of corresponding lesions; (2) correlation of the PET/CT images with available follow-up data for 18F-PSMA-11 and 68Ga-PSMA-11; and (3) assessment of the interobserver variability. DESIGN, SETTING, AND PARTICIPANTS: Prostate cancer patients (primary or biochemical recurrence) were randomised in a double-blind crossover design whereby each patient received both 18F-PSMA-11 and 68Ga-PSMA-11 PET/CT. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: All scans were reviewed and scored by three independent experienced nuclear physicians following the proposed guideline for the interpretation of PSMA-ligand PET/CT, as described by Eiber et al. RESULTS AND LIMITATIONS: In total, 82 patients were included for scan analyses. The primary endpoint was met: per patient, the proportions of positive scans rated by the three readers were 67%/67%, 65%/65%, and 73%/70% for 18F-PSMA-11/68Ga-PSMA-11 PET/CT. The miPSMA expression score was higher for 18F-PSMA-11 than for 68Ga-PSMA-11 for the reference reader. Follow-up data showed identical estimated sensitivity for both the 18F-PSMA-11 and the 68Ga-PSMA-11 scan (0.92, 0.83, and 0.92 for the three readers). A fair to good agreement among readers (at patient level) was obtained, which was demonstrated by a Light's kappa value of 0.59 for both tracers. CONCLUSIONS: The tracer 18F-PSMA-11 is noninferior to68Ga-PSMA-11. Superiority of 18F-PSMA-11 was limited to the miPSMA expression score, given by the reference reader. Inter-rater agreement was fair to good, and equal for both radiotracers. PATIENT SUMMARY: In this study, we compared two radiotracers: 18F-PSMA-11 and 68Ga-PSMA-11. We proved that 18F-PSMA-11 is not inferior to 68Ga-PSMA-11 for detecting prostate cancer and thus can be used as an alternative. Possible superiority of this tracer should be further investigated in specific subpopulations.


Assuntos
Radioisótopos de Gálio , Neoplasias da Próstata , Estudos Cross-Over , Radioisótopos de Flúor , Isótopos de Gálio , Glutaratos , Humanos , Ligantes , Masculino , Ácidos Fosfínicos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia
12.
Chem Commun (Camb) ; 58(45): 6530-6533, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35579270

RESUMO

Tubulin polyglycylation is a posttranslational modification that occurs primarily on the axonemes of flagella and cilia and has been shown to be essential for proper sperm motility. Inhibitors of both the initiase and elongase ligases (TTLL8 and TTLL10) are shown to inhibit tubulin glycylation in the low micromolar range.


Assuntos
Ácidos Fosfínicos , Tubulina (Proteína) , Cílios/metabolismo , Humanos , Masculino , Microtúbulos/metabolismo , Processamento de Proteína Pós-Traducional , Motilidade dos Espermatozoides , Tubulina (Proteína)/metabolismo
13.
Sci Rep ; 12(1): 6132, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35413967

RESUMO

Mutations in the Cystic Fibrosis Transmembrane Conductance Regulator gene (CFTR) are responsible for Cystic Fibrosis (CF). The most common CF-causing mutation is the deletion of the 508th amino-acid of CFTR (F508del), leading to dysregulation of the epithelial fluid transport in the airway's epithelium and the production of a thickened mucus favoring chronic bacterial colonization, sustained inflammation and ultimately respiratory failure. c407 is a bis-phosphinic acid derivative which corrects CFTR dysfunction in epithelial cells carrying the F508del mutation. This study aimed to investigate c407 in vivo activity in the F508del Cftrtm1Eur murine model of CF. Using nasal potential difference measurement, we showed that in vivo administration of c407 by topical, short-term intraperitoneal and long-term subcutaneous route significantly increased the CFTR dependent chloride (Cl-) conductance in F508del Cftrtm1Eur mice. This functional improvement was correlated with a relocalization of F508del-cftr to the apical membrane in nasal epithelial cells. Importantly, c407 long-term administration was well tolerated and in vitro ADME toxicologic studies did not evidence any obvious issue. Our data provide the first in vivo preclinical evidence of c407 efficacy and absence of toxicity after systemic administration for the treatment of Cystic Fibrosis.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Animais , Cloretos , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Transporte de Íons , Camundongos , Mutação , Ácidos Fosfínicos
14.
Molecules ; 27(4)2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35209031

RESUMO

In this report, a synthetic protocol for the preparation of phosphinic dipeptides of type 5 is presented. These compounds serve as valuable building blocks for the development of highly potent phosphinopeptidic inhibitors of medicinally relevant Zn-metalloproteases and aspartyl proteases. The proposed method is based on the tandem esterification of α-aminophosphinic and acrylic acids under silylating conditions in order to subsequently participate in a P-Michael reaction. The scope of the transformation was investigated by using a diverse set of readily available acrylic acids and (R)-α-aminophosphinic acids, and high yields were achieved in all cases. In most examples reported herein, the isolation of biologically relevant (R,S)-diastereoisomers became possible by simple crystallization from the crude products, thus enhancing the operational simplicity of the proposed method. Finally, functional groups corresponding to acidic or basic natural amino acids are also compatible with the reaction conditions. Based on the above, we expect that the practicality of the proposed protocol will facilitate the discovery of pharmacologically useful bioactive phosphinic peptides.


Assuntos
Acrilatos/química , Dipeptídeos , Ácidos Fosfínicos/química , Dipeptídeos/síntese química , Dipeptídeos/química , Esterificação
15.
Int J Mol Sci ; 23(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35163832

RESUMO

Recent studies have linked the activity of ER aminopeptidase 2 (ERAP2) to increased efficacy of immune-checkpoint inhibitor cancer immunotherapy, suggesting that pharmacological inhibition of ERAP2 could have important therapeutic implications. To explore the effects of ERAP2 inhibition on the immunopeptidome of cancer cells, we treated MOLT-4 T lymphoblast leukemia cells with a recently developed selective ERAP2 inhibitor, isolated Major Histocompatibility class I molecules (MHCI), and sequenced bound peptides by liquid chromatography tandem mass spectrometry. Inhibitor treatment induced significant shifts on the immunopeptidome so that more than 20% of detected peptides were either novel or significantly upregulated. Most of the inhibitor-induced peptides were 9mers and had sequence motifs and predicted affinity consistent with being optimal ligands for at least one of the MHCI alleles carried by MOLT-4 cells. Such inhibitor-induced peptides could serve as triggers for novel cytotoxic responses against cancer cells and synergize with the therapeutic effect of immune-checkpoint inhibitors.


Assuntos
Antígenos de Histocompatibilidade Classe I/química , Peptídeos/imunologia , Ácidos Fosfínicos/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Aminopeptidases , Apresentação de Antígeno , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Ácidos Fosfínicos/química , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Espectrometria de Massas em Tandem
16.
Clin Nucl Med ; 47(5): 441-443, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35020651

RESUMO

ABSTRACT: Primary mucinous tumors involving the prostate gland are rare. We describe MRI and 18F-PSMA-11 PET/MRI findings in a case of prostate adenocarcinoma with mucinous features. The prostate tumor showed inhomogeneous hyperintensity on T2-weighted images due to high extracellular mucin content and inhomogeneous 18F-PSMA-11 uptake with SUVmax of 12.5. This case indicates PSMA PET imaging may be helpful for detection of this uncommon variant of prostate adenocarcinoma.


Assuntos
Adenocarcinoma , Neoplasias da Próstata , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Radioisótopos de Gálio , Glutaratos , Humanos , Imageamento por Ressonância Magnética , Masculino , Ácidos Fosfínicos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia
17.
Vet Med Sci ; 8(2): 781-791, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34904397

RESUMO

BACKGROUND: Management and control of metabolic disorders in sheep around parturition is important. and various researchers have suggested different managerial solutions. Butaphosphan and cyanocobalamin are widely used for curing metabolic disorders resulting from poor nutrition, inadequate management or diseases. OBJECTIVES: It was hypothesised that butaphosphan and cyanocobalamin could improve the metabolism of ewes around parturition. METHODS: Twenty-eight clinically healthy 3-year-old pregnant Afshari ewes from 21 days before parturition were enrolled into four equal groups: control (Ctrl), B+C1, B+C2 and B+C3. The Ctrl group only received intravenous normal saline and B+C1, B+C2 and B+C3 ewes, respectively, received an intravenous combination of 10% butaphosphan and 0.005% cyanocobalamin at 2, 4 and 6 ml/ewe, on Days 19-21, 10-12 and 1-3 before parturition. Blood samples were taken from all the ewes on Days 21, 12 and 3 before lambing at parturition day and on days 3, 12 and 21 after parturition. A body condition score of all the ewes was assessed at blood sampling days, and lambs born from the ewes were weighed at birth and every 2 weeks up to 3 months. Serum concentrations of glucose, cortisol, non-esterified fatty acids, beta-hydroxy butyric acid, triglyceride, cholesterol, high-, low- and very-low-density lipoproteins, aspartate aminotransferase and alanine aminotransferase were measured. RESULTS: This drug combination decreased circulating glucose, cortisol, lipid profile and hepatic enzymes via dose-dependent manner, 6 ml of this drug compound/ewe was more potent than 4 and 2 ml/ewe. The lambs' weight from mothers receiving 6 ml of this combination was significantly higher than those of the others. CONCLUSIONS: It may be suggested that the intravenous administration of 6 ml/ewe of this combination for 3 consecutive days in three states before parturition had prophylactic effects on metabolic disorders of ewes and enhanced the lambs weight gain after birth.


Assuntos
Hidrocortisona , Parto , Administração Intravenosa/veterinária , Animais , Butilaminas , Feminino , Glucose/farmacologia , Hidrocortisona/farmacologia , Ácidos Fosfínicos , Gravidez , Ovinos , Vitamina B 12/farmacologia , Aumento de Peso
18.
J Hazard Mater ; 424(Pt B): 127522, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34879517

RESUMO

As an emerging alternative legacy perfluoroalkyl substance, C6/C6 PFPiA (perfluoroalkyl phosphinic acids) has been detected in aquatic environments and causes potential risks to human health. The degradation mechanisms of C6/C6 PFPiA in a dielectric barrier discharge (DBD) plasma system were explored using validated experimental data and density functional theory (DFT) calculations. Approximately 94.5% of C6/C6 PFPiA was degraded by plasma treatment within 15 min at 18 kV. A relatively higher discharge voltage and alkaline conditions favored its degradation. C6/C6 PFPiA degradation was attributed to attacks of •OH, •O2-, and 1O2. Besides PFHxPA and C2 -C6 shorter-chain perfluorocarboxylic acids, several other major intermediates including C4/C6 PFPiA, C4/C4 PFPiA, and C3/C3 PFPiA were identified. According to DFT calculations, the potential energy surface was proposed for possible reactions during C6/C6 PFPiA degradation in the discharge plasma system. Integrating the identified intermediates and DFT results, C6/C6 PFPiA degradation was deduced to occur by stepwise losing CF2, free radical polymerization, and C-C bond cleavage. Furthermore, the DBD plasma treatment process decreased the toxicity of C6/C6 PFPiA to some extent. This study provides a comprehensive understanding of C6/C6 PFPiA degradation by plasma advanced oxidation.


Assuntos
Poluentes Químicos da Água , Humanos , Ácidos Fosfínicos
19.
Environ Technol ; 43(5): 737-750, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32727287

RESUMO

The objectives of this work were to develop polyacrylonitrile nanofibres modified with the commercial Cyanex 272 extractor and apply them for the recovery of gallium present in aqueous solution. The nanofibres were produced using the centrifugation technique, employing Forcespinning® equipment. The average nanofibre diameter ranged from 530 to 840 nm. The highest adsorption of gallium was achieved at pH 2.5, with a pseudo-second order kinetic model and the Freundlich equilibrium isotherm model providing the best fits of the experimental data. The thermodynamic parameters showed that the adsorption was spontaneous, favourable, and endothermic. The maximum capacity of the PAN/Cyanex 272 nanofibres for the recovery of gallium was 38.93 mg g-1. In successive reuse cycles, the nanofibres showed a small decrease of the adsorption capacity for the metal after the first cycle, while the efficiency remained constant in the subsequent cycles. The desorption efficiency remained constant throughout the cycles, with values in the range 80%-90%. The findings demonstrated that PAN/Cyanex 272 nanofibres have excellent potential for use as adsorbents, providing good capacity for the recovery of gallium and satisfactory stability during reuse in several cycles.


Assuntos
Gálio , Nanofibras , Poluentes Químicos da Água , Resinas Acrílicas , Adsorção , Cinética , Ácidos Fosfínicos , Termodinâmica , Poluentes Químicos da Água/análise
20.
Sci Rep ; 11(1): 22623, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34799653

RESUMO

This two-part preclinical study aims to evaluate prostate specific membrane antigen (PSMA) as a valuable target for expression-based imaging applications and to determine changes in target binding in function of varying apparent molar activities (MAapp) of [18F]AlF-PSMA-11. For the evaluation of PSMA expression levels, male NOD/SCID mice bearing prostate cancer (PCa) xenografts of C4-2 (PSMA+++), 22Rv1 (PSMA+) and PC-3 (PSMA-) were administered [18F]AlF-PSMA-11 with a medium MAapp (20.24 ± 3.22 MBq/nmol). SUVmean and SUVmax values were respectively 3.22 and 3.17 times higher for the high versus low PSMA expressing tumors (p < 0.0001). To evaluate the effect of varying MAapp, C4-2 and 22Rv1 xenograft bearing mice underwent additional [18F]AlF-PSMA-11 imaging with a high (211.2 ± 38.9 MBq/nmol) and/or low MAapp (1.92 ± 0.27 MBq/nmol). SUV values showed a significantly increasing trend with higher MAapp. Significant changes were found for SUVmean and SUVmax between the high versus low MAapp and medium versus low MAapp (both p < 0.05), but not between the high versus medium MAapp (p = 0.055 and 0.25, respectively). The effect of varying MAapp was more pronounced in low expressing tumors and PSMA expressing tissues (e.g. salivary glands and kidneys). Overall, administration of a high MAapp increases the detection of low expression tumors while also increasing uptake in PSMA expressing tissues, possibly leading to false positive findings. In radioligand therapy, a medium MAapp could reduce radiation exposure to dose-limiting organs with only limited effect on radionuclide accumulation in the tumor.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glutamato Carboxipeptidase II/biossíntese , Glutaratos/farmacocinética , Glicoproteínas de Membrana/biossíntese , Ácidos Fosfínicos/farmacocinética , Neoplasias da Próstata/metabolismo , Complexo de Endopeptidases do Proteassoma/biossíntese , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/patologia , Ligação Proteica , Compostos Radiofarmacêuticos , Distribuição Tecidual
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