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1.
Environ Sci Technol ; 58(18): 7791-7801, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38653734

RESUMO

Microplastics (MPs) pose potential health risks to the intestinal tract and gut microbiota, a topic that has garnered significant attention. However, the absence of quantitative assessment methods for human gut MP exposure impedes related health risk assessments. Here, we performed long-term continuous exposure experiments on mice using MPs that mimic actual human exposure characteristics. The daily excretion of fecal MPs and the concentrations of phthalates (PAEs) and their metabolites (mPAEs) in serum and urine were detected. The cumulative excretion rate of fecal MPs remains stable at about 93%. A significant linear correlation was observed between MP exposure and concentration of mPAEs in urine for both low MP (LMP; 150 µg of MPs/d) (R2 = 0.90) and high MP (HMP; 360 µg of MPs/d) groups (R2 = 0.97). Moreover, a strong correlation was found between daily PAEs exposure and total MP-associated PAEs exposure in both LMP (R2 = 0.77) and HMP (R2 = 0.88) groups. Based on these findings, we established a noninvasive model and evaluated multiple MP exposure parameters in the human gut across 6 continents, 30 countries, and 133 individuals. This study offers novel insights for the quantitative assessment of in vivo MP exposure and provides technical support for assessing the health risks of MPs.


Assuntos
Microplásticos , Camundongos , Animais , Humanos , Fezes/química , Ácidos Ftálicos/urina , Ácidos Ftálicos/metabolismo , Exposição Ambiental
2.
Angew Chem Int Ed Engl ; 62(43): e202313099, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37694769

RESUMO

The development of practical materials for (de)hydrogenation reactions is a prerequisite for the launch of a sustainable hydrogen economy. Herein, we present the design and construction of an atomically dispersed dual-metal site Co/Cu-N-C catalyst allowing significantly improved dehydrogenation of formic acid, which is available from carbon dioxide and green hydrogen. The active catalyst centers consist of specific CoCuN6 moieties with double-N-bridged adjacent metal-N4 clusters decorated on a nitrogen-doped carbon support. At optimal conditions the dehydrogenation performance of the nanostructured material (mass activity 77.7 L ⋅ gmetal -1 ⋅ h-1 ) is up to 40 times higher compared to commercial 5 % Pd/C. In situ spectroscopic and kinetic isotope effect experiments indicate that Co/Cu-N-C promoted formic acid dehydrogenation follows the so-called formate pathway with the C-H dissociation of HCOO* as the rate-determining step. Theoretical calculations reveal that Cu in the CoCuN6 moiety synergistically contributes to the adsorption of intermediate HCOO* and raises the d-band center of Co to favor HCOO* activation and thereby lower the reaction energy barrier.

3.
Environ Sci Technol ; 56(17): 12625-12634, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35947769

RESUMO

Regeneration of spent V2O5-WO3/TiO2 catalysts is highly desirable, especially for those containing hypertoxic As, which is categorized as hazardous waste. However, common solution-leaching methods suffer from the trade-off between As removal and V2O5 retention, and it would be necessary to introduce extra proceedings like ingredients reimplantation and As-bearing waste treatment after regeneration. Herein, a formic acid-mediated regeneration strategy has been developed to achieve superior catalytic activity, short timescale regeneration, and nontoxic metallic As recycling with controllable and safe conduction. The specific activity of the optimal regenerated catalyst reaches 98.3% of the fresh catalyst with 99.1% As removal and less than 1.8% V loss within 15 min. Structure characterizations reveal that the distorted VOx molecular structure, surface acidity, and redox property recover to the fresh level after regeneration. In situ investigation of the regeneration process indicates that As-OH removal together with V-OH generation occurs at the first regeneration stage, followed by the active center V═O sites over-reduction at the second stage. The retained V═O species by suitable regeneration temperature and time are essential for NH3-selective catalytic reduction (SCR) since As existence and VOx over-reduction will separately cause unstable and excessive NH3 adsorption to further suppress the reaction cycle. The developed strategy and improved understanding of active site protection would exert benefits on the development of efficient and time-saving regeneration methods for spent catalysts.


Assuntos
Venenos , Amônia/química , Catálise , Formiatos , Titânio/química
4.
Front Public Health ; 10: 1063605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36703819

RESUMO

Background: Vocational education is an important part of high school education in China. However, there is little research on high school students' mental health. This study aimed to investigate the prevalence of suicidal behavior (SB) among this population and the mediating role of insomnia, depression, anxiety, and stress in the relationship between Internet addiction (IA) and SB using a structural equation model. Methods: A cross-sectional questionnaire survey was conducted among several vocational high school students in Hunan Province, and 7,968 valid questionnaires were obtained. General demographic data and data from the Dual-Mode Self-Control Scale, Athens Insomnia Scale, Depression Anxiety Stress scale-21, and Revised Chen Internet Addiction Scale were collected. A structural equation model was used to explore the different pathways from IA to SB. Results: Among the participants, 37.7, 15.7, and 21.8% reported suicidal ideation, plans, and attempts, respectively. The structural equation model confirmed that IA was indirectly related to SB and was mediated by insomnia and/or depression, anxiety, and stress. Limitations: First, we only recruited students from vocational schools in Hunan Province, therefore, the sample may not represent the entire population of vocational students in China. Second, self-report scales were used in this study, and clinical diagnosis required professional interviews. Third, since this study had a cross-sectional design, the causal relationship between the variables could not be determined. Conclusions: The prevalence of SB among vocational high school students in China was significantly high. The prevention of SB related to IA can be attributed to the improvement of insomnia and emotional problems.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Ideação Suicida , Humanos , Transtorno de Adição à Internet , Estudos Transversais , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Depressão/epidemiologia , Depressão/psicologia , Estudantes/psicologia , China/epidemiologia
5.
Chemosphere ; 263: 127893, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32835971

RESUMO

Toluene and styrene were two typical aromatic VOCs which were commonly used and coexistence in the exhaust gases from industrial manufacturing. Their simultaneous removal performances under non-thermal plasma (NTP) and NTP-catalysis were carried out and compared by a single stage coaxial dielectric barrier discharge (DBD) reactor. The effects of VOCs mixture, humidity, materials filling in the discharge zoon on the removal efficiency, COx selectivity, byproducts types and their emission levels were deeply investigated to explore the degradation mechanism and coexistence effect. Experimental results showed that the toluene removal was significantly inhibited when treated together with styrene under plasma treatment. But that of styrene was hardly affected at the same conditions. It was found that benzaldehyde as the primary organic byproducts from styrene consumed the oxidizing particles (O and . OH), limiting the conversion of toluene. The introduction of Cu-doped MnO2 materials significantly improved the VOCs removal performance with nearly 100% conversion to COx at a discharge power less than 30 W, as well as O3 generation from more than 1.2 mg L-1 by NTP to 1.6 × 10-3 mg L-1 by NTP-catalysis. With the help of in situ FT-IR, it was believed that catalysts not only accelerated the adsorption and degradation of pollutants but also utilized ozone to involve this process. At last, a plausible explanation on binary coexistence effect under different conditions had been suggested and discussed.


Assuntos
Tolueno/química , Compostos Orgânicos Voláteis/química , Adsorção , Catálise , Compostos de Manganês , Óxidos , Ozônio , Gases em Plasma , Espectroscopia de Infravermelho com Transformada de Fourier , Estireno
6.
Front Vet Sci ; 7: 547047, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195520

RESUMO

Fatty liver disease is one of the most common disorders afflicting dairy cows during the postpartum period, and is associated with increased blood non-esterified fatty acid (NEFA) uptake by the liver. Major long-chain fatty acids (LCFA) in NEFA are palmitic (PA), palmitoleic (POA), stearic (SA), oleic (OA), and linoleic (LA) acid. In order to investigate the characteristics of lipid accumulation and injury caused by these NEFA, primary calf hepatocytes were isolated and challenged for 12 h with 1.2 mmol/L PA, POA, SA, OA, LA, or a mixture of these LCFA (NEFA). Compared with POA, OA, and LA, culture with PA and SA led to greater abundance of CCAAT-enhancer binding protein, glucose-regulated protein 78 mRNA, and stearoyl-CoA desaturase 1 mRNA along with greater concentrations of H2O2, malondialdehyde and reactive oxygen species (ROS). Although culture with POA, OA, and LA led to lower very low density lipoprotein (VLDL) concentration in cell culture medium, POA and OA led to greater concentrations of triacylglycerol, protein abundance of sterol regulatory element-binding protein 1c, fatty acid synthase, acetyl coenzyme A carboxylase 1, ApoB100, and sortilin 1 (SORT1). Compared with individual fatty acids, culture with NEFA led to an intermediate degree of lipid accumulation and hepatocytes damage. Overall, the data suggest that saturated fatty acids cause more severe oxidative and ER stress. However, unsaturated fatty acids cause serious lipid accumulation. Furthermore, a fatty acid balanced nutrient regulation was suggested useful improve liver health of transition period dairy cows.

7.
J Cell Physiol ; 235(9): 6246-6256, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32012270

RESUMO

To evaluate the effects of fatty acids on endoplasmic reticulum (ER) stress, oxidative stress, and lipid damage. We treated BRL3A rat liver cells with, linoleic (LA), linolenic, oleic (OA), palmitic (PA), palmitoleic (POA), or stearic (SA) acid for 12 hr. The characteristics of cell lipid deposition, oxidative stress indexes, ER stress markers, nuclear factor κB p65 (NF-κB p65), lipid synthesis and transport regulators, and cholesterol metabolism regulators were analyzed. Endoplasmic chaperones like glucose-regulated protein 78, CCAAT-enhancer-binding protein, NF-κB p65, hydrogen peroxide, and malonaldehyde in PA- and SA-treated cells were significantly higher than in other treated cells. Deposition of fatty acids especially LA and POA were significantly increased than in other treated cells. De novo lipogenesis regulators sterol regulatory element-binding protein 1c, fatty acid synthase, and acetyl-coenzyme A carboxylase 1 (ACC1) expression were significantly increased in all fatty acid stimulation groups, and PA- and SA-treated cells showed lower p-ACC1 expression and higher scd1 expression than other fatty acid groups. Very low-density lipoprotein synthesis and apolipoprotein B100 expression in free fatty acids treated cells were significantly lower than control. PA, SA, OA, and POA had shown significantly increased cholesterol synthesis than other treated cells. PA and SA showed the lower synthesis of cytochrome P7A1 and total bile acids than other fatty acids treated cells. Excess of saturated fatty acids led to severe ER and oxidative stress. Excess unsaturated fatty acids led to increased lipid deposition in cultured hepatocytes. A balanced fatty acid intake is needed to maintain lipid homeostasis.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos/farmacologia , Fígado Gorduroso/tratamento farmacológico , Lipogênese/genética , Acetil-CoA Carboxilase/genética , Animais , Células Cultivadas , Ácido Graxo Sintases/genética , Ácidos Graxos/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Ácido Linoleico/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/biossíntese , Lipídeos/genética , Lipogênese/efeitos dos fármacos , Lipoproteínas VLDL/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ácido Oleico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ácido Palmítico/farmacologia , Ratos , Ácidos Esteáricos/farmacologia , Ácido alfa-Linolênico/farmacologia
8.
Acta Biochim Pol ; 65(3): 443-447, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30212593

RESUMO

Oleic acid (OA) is widely used in pathology studies of hepatocellular lipid deposition. Identifying the effects of different solvents on OA-induced liver lipid deposition would be beneficial for studies on hepatocytes. We treated BRL 3A cells with OA dissolved in different solvents. After 12 h incubation, cell viability was assessed using MTT assays. Reactive oxygen species (ROS), triglyceride (TG) and total cholesterol (TC) counts, and the expression level of glucose regulated protein (GRP78), sterol regulatory element binding protein (SREBP-1C) and fatty acid synthase (FAS) were analyzed. Water, PBS and DMSO were disadvantageous to the dissolution of OA and did not cause an OA-induced response in hepatocytes. In the alcohol+OA-treated cells, the severe ER stress, oxidative stress and cellular fat deposition were significantly increased. BSA promoted cell growth and the cells treated with 1.2% BSA+OA showed a lower grade TG and endoplasmic reticulum stress compared with KOH+OA and alcohol+OA treatments. KOH had no significant influence on BRL 3A cells viability. When treated with OA dissolved in KOH, BRL 3A cells showed a typical hepatocyte damage. KOH was considered the suitable choice for an OA solvent for BRL 3A cells in hepatic lipidosis research.


Assuntos
Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Ácido Oleico/farmacologia , Solventes/química , Animais , Linhagem Celular , Colesterol/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácido Graxo Sintases/metabolismo , Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/metabolismo , Fígado/citologia , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/metabolismo , Receptor fas/efeitos dos fármacos , Receptor fas/genética
9.
J Dairy Res ; 84(4): 407-413, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29154737

RESUMO

High concentrations of non-esterified fatty acid (NEFA) and ß-hydroxybutyrate (BHBA) in cows' blood caused by ketosis are associated with inflammatory states. We hypothesised that ketosis in postparturient dairy cows would result in altered levels on inflammation-related proteins not only in plasma but also in the milk fat globule membranes (MFGM). Thirty cows were selected from a dairy farm in Heilongjiang, China. Inflammatory milk fat globule membrane proteins were detected using ELISA kits, and a fully automatic biochemical analyser was used to measure the concentrations of BHBA, NEFA, glucose (GLU) and triglyceride (TG) in plasma. MFGM protein from milk of ketotic cows contained significantly different concentrations of acute-phase response proteins (complement C3 (C3), prothrombin (F2), alpha-1-acid glycoprotein (ORM1), inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4), alpha-2-HS-glycoprotein (AHSG), complement C9 (C9), complement regulatory protein variant 4 (CD46)) in comparison with milk from non-ketotic cows. Blood concentrations of C3, complement C9 (C9), tumour necrosis factor α (TNFα), MFGM C3, monocyte differentiation antigen CD14 (CD14) and ORM1 levels were correlated with energy balance. ITIH4 and CD46 increased, and AHSG and ORM1 decreased before the onset of ketosis. These biomarkers offer potential as predictors and monitors of ketosis in at-risk cows.


Assuntos
Biomarcadores/análise , Doenças dos Bovinos/metabolismo , Glicolipídeos/química , Glicoproteínas/química , Cetose/veterinária , Proteínas de Membrana/análise , Ácido 3-Hidroxibutírico/sangue , Proteínas de Fase Aguda/análise , Reação de Fase Aguda , alfa-Globulinas/análise , Animais , Bovinos , China , Metabolismo Energético , Ácidos Graxos não Esterificados/sangue , Feminino , Cetose/metabolismo , Gotículas Lipídicas , Proteína Cofatora de Membrana/análise , Orosomucoide/análise , alfa-2-Glicoproteína-HS/análise
10.
Med Sci Monit ; 22: 2363-73, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27385226

RESUMO

BACKGROUND The lymphatic system plays a significant role in the defense of a subject against breast cancer and is one of the major pathways for the metastasis of breast cancer. To improve the prognosis, many means, including surgery, radiotherapy, and chemotherapy, have been used. However, the combination of all these modalities has limited efficacy. Lymph nodes, therefore, have become an exceptionally potential target organ in cancer chemotherapy. MATERIAL AND METHODS A lymph node metastatic model of breast cancer was established in BALB/c mice. Magnetic multi-walled carbon nanotube carrier with good adsorption and lymph node-targeting capacity was prepared and conjugated with doxorubicin to make the magnetic multi-walled carbon nanotube-doxorubicin suspension. Dispersions of doxorubicin, magnetic multi-walled carbon nanotube-doxorubicin, and magnetic multi-walled carbon nanotube were injected into lymph node metastatic mice to compare their inhibitory effects on tumor cells in vivo. Inhibition of these dispersions on EMT-6 breast cancer cells was detected via MTT assay in vitro. RESULTS Although no significant difference was found between the effects of doxorubicin and magnetic multi-walled carbon nanotube-doxorubicin with the same concentration of doxorubicin on EMT-6 breast cancer cells in vitro, in terms of sizes of metastatic lymph nodes and xenograft tumors, apoptosis in metastatic lymph nodes, and adverse reactions, the magnetic multi-walled carbon nanotube-doxorubicin group differed significantly from the other groups. CONCLUSIONS The magnetic multi-walled carbon nanotube-doxorubicin clearly played an inhibitory role in lymph node metastases to EMT-6 breast cancer cells.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Magnetismo , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Nanotubos de Carbono , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Linfonodos/patologia , Metástase Linfática , Camundongos , Camundongos Endogâmicos BALB C , Prognóstico , Distribuição Aleatória
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 35(2): 292-4, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25736133

RESUMO

OBJECTIVE: To investigate the effect of mTOR signal transduction pathway and down-regulating anti-oncogene PTEN on the growth of breast cancer MCF-7 cells. METHODS: MCF-7 cells were transfected with the eukaryotic expression plasmid pcDNA3.1-mTOR and non-loaded plasmid, and the expression of mTOR in the cells was detected using Western blotting. Flow cytometry was used to analyze apoptosis and cell cycle of the transfected cells, and the expression of PTEN was detected after transfection. RESULTS: The cells transfected with pcDNA3.1-mTOR showed a increased growth rate than those transfected with the non-loaded plasmid and those without transfection. The expression of the protein PTEN decreased obviously in the cells after mTOR trasnfection. CONCLUSION: mTOR can regulate the expression of PTEN via PI3K/AKT/PTEN pathways through a negative feedback mechanism. Increased mTOR expression promotes MCF-7 cell growth, suggesting the potential value of mTOR specific inhibitor in the treatment of breast cancer.


Assuntos
Neoplasias da Mama/patologia , Plasmídeos , Serina-Treonina Quinases TOR/genética , Apoptose , Ciclo Celular , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais , Transfecção
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