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1.
Ecotoxicol Environ Saf ; 255: 114807, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36948011

RESUMO

Polyphenols, as an important category of natural organics, are ubiquitous in plants and structurally diverse. Batch experiments were conducted to investigate the role of natural polyphenol, such as gallic acid (GA) and tannic acid (TA), in the biochemical behavior of Cr(VI) in soil media. GA and TA can effectively convert Cr(VI) to Cr(III) under neutral conditions (pH 7.0). However, there are significant differences in the transport, leaching toxicity, and bioavailability of reduced Cr(III) between the two systems. UV-vis spectra, chromium (Cr) mass balance, speciation distribution, and X-ray photoelectron spectroscopy were used to explore the intrinsic mechanisms of Cr(VI) reduction and (im)mobilization in the presence of GA or TA. Results showed that the reduction of Cr(VI) by GA was accompanied by poor immobilization of reduced Cr(III), especially at high GA concentrations (4-10 g/L), which was associated with the formation of soluble Cr(III) complexes. After treatment with 4 g/L GA, 51.49 ± 3.04% of the Cr in GA system was mobilized as complexes into aqueous phase. In contrast, the reduction of Cr(VI) and the subsequent precipitation of reduced Cr(III) was dominant in the TA system. After treatment with 4 g/L TA, 97.24 ± 0.31% of the total Cr in the TA system was immobilized into soil phase and transformed into more stable fractions. Our findings provide new insights into how natural organics shape the fate and transport of Cr in soils, which also have substantial implications for the development of Cr sequestration technology.


Assuntos
Polifenóis , Poluentes do Solo , Poluição Ambiental , Cromo/análise , Solo/química , Poluentes do Solo/análise , Taninos
2.
Gels ; 8(5)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35621549

RESUMO

Fumaric acid sludge (FAS) by-produced from phthalic anhydride production wastewater treatment contains a large amount of refractory organic compounds with a complex composition, which will cause environmental pollution unless it is treated in a deep, harmless manner. FAS included saturated carboxylic acid, more than 60%, and unsaturated carboxylic acid, close to 30%, which accounted for the total mass of dry sludge. A new oil well drilling fluid filtrate loss reducer, poly(AM-AMPS-FAS) (PAAF), was synthesized by copolymerizing FAS with acrylamide (AM) and 2-acrylamide-2-methyl propane sulfonic acid (AMPS). Without a refining requirement for FAS, it can be used as a polymerizable free radical monomer for the synthesis of PAAF after a simple drying process. The copolymer PAAF synthesis process was studied, and the optimal monomer mass ratio was determined to be AM:AMPS:FAS = 1:1:1. The temperature resistance of the synthesized PAAF was significantly improved when 5% sodium silicate was added as a cross-linking agent. The structural characterization and evaluation of temperature and complex saline resistance performance of PAAF were carried out. The FT-IR results show that the structure of PAAF contained amide groups and sulfonic acid groups. The TGA results show that PAAF has good temperature resistance. As an oilfield filtrate loss reducer, the cost-effective copolymer PAAF not only has excellent temperature and complex saline resistance, the API filtration loss (FL) was only 13.2 mL/30 min after 16 h of hot rolling and aging at 150 °C in the complex saline-based mud, which is smaller compared with other filtrate loss reducer copolymers, but it also has little effect on the rheological properties of drilling fluid.

3.
Chemosphere ; 297: 134081, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35202661

RESUMO

The rapid reductive immobilization of Cr(VI) from the aqueous solution was achieved by reduction to Cr(III) using tannic acid (TA), and subsequent pH-triggering precipitation of the organo-Cr(III) complexes formed in the redox reaction. The effects of TA concentration, temperature, and solution pH on the reduction of Cr(VI) were examined by batch experiments, and the rapid redox reduction followed a second-order kinetics with respect to Cr(VI) concentration in the pH range of 2.0-3.0. UV-visible spectra, FTIR, and XPS confirmed the complete detoxification of Cr(VI) concomitant with carboxylation of partial phenolic hydroxyls in TA. Synchronously, the reduced Cr(III) coordinated with carboxyl groups in oxidized TA (OTA) to form complexes, which exhibited remarkable pH-dependent size distribution characteristics as illustrated by SEM images and sequential filtration/ultrafiltration. The resulted Cr(III) complexes could aggregate into colloids with larger size and precipitate out at pH range of 6.0-8.0 via cross-linking, thereby leading to 93% Cr and 89% TOC immobilization. An eco-friendly and cost-effective method for Cr(VI) elimination and immobilization is provided because polyphenols are natural polymers derived from plants.


Assuntos
Taninos , Poluentes Químicos da Água , Adsorção , Cromo/análise , Concentração de Íons de Hidrogênio , Cinética , Água , Poluentes Químicos da Água/análise
4.
Pediatr Res ; 89(7): 1706-1714, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33075801

RESUMO

BACKGROUND: White matter injury (WMI) induced by intrauterine inflammation can cause adverse neurological outcomes. Fibrinogen-like protein 2 (FGL2)/fibroleukin is an important trigger of inflammatory responses and is involved in some cerebral diseases. However, the role of FGL2 in intrauterine inflammation-induced WMI remains unclear. METHODS: Lipopolysaccharide (LPS) was intraperitoneally injected into wild-type and FGL2 knockout mice to induce intrauterine inflammation. Body weight and brain weight of offspring were monitored. Major basic protein (MBP) expression was evaluated to demonstrate the myelination of offspring. To investigate the regulatory mechanism of FGL2, cytokine expression, microglial polarization, and the activation of mitogen-activated protein kinase (MAPK) signaling pathway in the offspring were analyzed. RESULTS: Upon LPS exposure, FGL2 knockout offspring showed a significant increase in body weight loss. MBP reduction induced by LPS was prevented in FGL2 knockout offspring. Expression levels of proinflammatory cytokines interleukin-1ß (IL-1ß) and tumor necrosis factor-α, and M1 marker CD86 were suppressed, while the expression levels of anti-inflammatory cytokines IL-10 and M2 marker CD206 were increased. FGL2 deficiency significantly inhibited the phosphorylation of p38MAPK and c-Jun N-terminal kinase (JNK) protein. CONCLUSIONS: FGL2 deficiency can ameliorate WMI induced by intrauterine inflammation, reducing inflammatory cascade and improving hypomyelination, through the regulation of microglial polarization and MAPK signaling pathways. IMPACT: Intrauterine inflammation induces WMI leading to severe neurological sequelae. FGL2 plays an important role in the progression of WMI induced by intrauterine inflammation. FGL2 deficiency can protect against WMI by inhibiting p38 MAPK and JNK phosphorylation, regulating microglia polarization, and reducing inflammation response. FGL2 could be a novel molecular target for protecting against WMI induced by intrauterine inflammation.


Assuntos
Lesões Encefálicas/etiologia , Fibrinogênio/genética , Inflamação/complicações , Útero/patologia , Substância Branca/lesões , Animais , Feminino , Inflamação/genética , Camundongos , Camundongos Endogâmicos BALB C
5.
Horm Res Paediatr ; 91(4): 271-277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31212299

RESUMO

BACKGROUND: Circulating asprosin is a newly discovered adipokine that triggers the release of hepatic glucose stores and increases appetite. Asprosin levels are elevated in adult obese men as well as in mice, and reductions in asprosin protect against the hyperinsulinism associated with metabolic syndrome in mice with diet-induced obesity, which indicates a potential therapeutic role of asprosin in obesity and type 2 diabetes. OBJECTIVES: Few data on asprosin in children are available, which is why this study aimed to assess concentrations of fasting asprosin, as well as its relationship to parameters of glucose and lipid metabolism, in children. METHODS: Data on clinical and metabolic parameters were collected from 40 healthy normal-weight and 47 obese children. Circulating asprosin levels were measured using an ELISA. RESULTS: The concentrations of fasting asprosin were lower in the obese children (9.24 ± 4.11 ng/mL) than in the normal-weight controls (12.33 ± 4.18 ng/mL, p < 0.001). When comparing the two groups by sex, both the boys and the girls showed similar trends. In within-group comparison, the asprosin levels were lower in boys than in girls only in the obese group (8.13 ± 4.10 vs. 10.61 ± 3.78 ng/mL, p = 0.013) but not in the control group. Interestingly, asprosin was correlated with ALT after adjusting for age and sex in all participants; in boys, asprosin was correlated with BMI, HOMA-IR, insulin, and HDL after adjusting for age. CONCLUSIONS: Concentrations of asprosin were significantly lower in obese children than in normal-weight children, and there was a gender difference in asprosin concentration. Our results suggest a complex role for asprosin in energy metabolism.


Assuntos
Metabolismo Energético , Proteínas dos Microfilamentos/sangue , Obesidade Infantil/sangue , Fragmentos de Peptídeos/sangue , Hormônios Peptídicos/sangue , Adolescente , Fatores Etários , Criança , Pré-Escolar , Feminino , Fibrilina-1 , Humanos , Lactente , Recém-Nascido , Masculino , Fatores Sexuais
6.
Curr Med Sci ; 38(5): 868-874, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30341522

RESUMO

Wnt1-inducible signaling pathway protein-1 (WISP1), a member of the CCN family, is increasingly being recognized as a potential target for obesity and type 2 diabetes mellitus. Recent studies have shown that WISP1 can regulate low-grade inflammation in obese mice, and circulating WISP1 levels are associated with obesity and type 2 diabetes mellitus in adults. Herein, we measured serum WISP1 levels in obese youth and explored its relationships with pro-inflammatory cytokine interleukin 18 (IL-18) and other metabolic indexes. Totally, 44 normal-weight and 44 obese children and adolescents were enrolled. Physical and laboratory data were recorded, and then serum levels of WISP1 and IL-18 were determined by enzyme-linked immunosorbent assays. Results showed that serum levels of WISP1 were significantly higher in obese children and adolescents than in normal-weight healthy controls (1735.44±15.29 vs. 1364.08±18.69 pg/mL). WISP1 levels were significantly positively correlated with body mass index (BMI) and BMI z-score (r=0.392, P=0.008; r=0.474, P=0.001, respectively) in obese group; circulating IL-18 was increased in obese individuals (1229.06±29.42 vs. 295.87±13.30 pg/mL). Circulating WISP1 levels were significantly correlated with IL-18 (r=0.542, P<0.001), adiponectin (r=0.585, P<0.001) and leptin (r=0.592, P<0.001). The multivariate stepwise regression analysis showed that higher IL-18 levels represented the main determinant of increased WISP1 levels after adjusting for BMI, waist circumference, fasting insulin, homeostatic model assessment of insulin resistance (HOMA-IR) and HbA1c in obese individuals (ß=0.542, P=0.000). WISP1 can be involved in glucose/lipid metabolism in obese youth, which may be modulated by IL-18. Increased WISP1 levels may be a risk factor of obesity and insulin resistance, and WISP1 has a potential therapeutic effect on insulin resistance in obese children and adolescents.


Assuntos
Proteínas de Sinalização Intercelular CCN/sangue , Diabetes Mellitus Tipo 2/sangue , Interleucina-18/sangue , Obesidade/sangue , Proteínas Proto-Oncogênicas/sangue , Adolescente , Glicemia , Índice de Massa Corporal , Criança , Pré-Escolar , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Glucose/metabolismo , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Resistência à Insulina/genética , Metabolismo dos Lipídeos/genética , Masculino , Obesidade/genética , Obesidade/fisiopatologia , Circunferência da Cintura , Proteína Wnt1/genética
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