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1.
Langmuir ; 39(50): 18621-18630, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38054694

RESUMO

Composite phase change materials (PCMs) are of great importance for the storage and conversion of energy. In this study, a multishell metal oxide hollow microsphere (CuOHS) was prepared by the hydrothermal method, and a new composite PCM (CuOHS@PCMs) for energy storage and conversion purposes was developed by effectively absorbing fatty amines [namely, tetradecylamine (TDA), hexadecylamine (HDA), and octadecylamine (ODA)] PCMs into the CuOHS via the abundant micropores located on the surface of the microsphere. The incorporation of uncontaminated phase alteration substances with CuOHS yields superior light absorption and leak prevention traits. The three CuOHS@PCMs, specifically CuOHS@TDA, CuOHS@HDA, and CuOHS@ODA, possess considerable latent heats of 198.8, 192.6, and 196.0 J·g-1, respectively, and exhibit desirable thermal properties even after completing 50 and 100 thermal cycles. Moreover, under illumination, the photothermal conversion efficiencies of the three variations of CuOHS@PCMs were 84.0, 81.4, and 78.0%. This CuOHS@PCMs, which are based on CuOHS, have considerable potential in the fields of photothermal conversion, solar energy harvesting, and storage.

2.
Anticancer Drugs ; 34(3): 351-360, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729006

RESUMO

Growth differentiation factor 15 (GDF15) is a pleiotropic cytokine, which is involved in the cellular stress response following acute damage. However, the functional role of GDF15 in triple-negative breast cancer (TNBC) has not been fully elucidated. ELISA, Western blot, and PCR assays as well as bioinformatics analyses were conducted to observe the expression of GDF15. Cell Counting Kit-8, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and crystal violet staining assays were conducted to evaluate paclitaxel resistance and cell viability. Cell apoptosis was analyzed by Western blotting. Murine xenograft model assay was employed to evaluate tumor growth in vivo . Our data indicate that GDF15 is markedly elevated in paclitaxel-resistant TNBC cells, which is significantly associated with unfavorable prognosis. Silencing of GDF15 robustly inhibits the proliferation of tumor cells and increases their sensitivity to paclitaxel in vitro and in vivo , whereas the treatment of purified GDF15 protein confers breast cancer cells with chemoresistance ability. Moreover, GDF15 activates protein kinase B (AKT) /mammalian target of rapamycin (mTOR) signaling, inhibition of AKT or mTOR reverses the prosurvival effect of GDF15 and enhances the antitumor efficacy of paclitaxel in TNBC cells. Altogether, our study uncovers the role of GDF15 in tumor growth and paclitaxel resistance, implicating a potential therapeutic target for TNBC.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias de Mama Triplo Negativas , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Fator 15 de Diferenciação de Crescimento/metabolismo , Fator 15 de Diferenciação de Crescimento/farmacologia , Fator 15 de Diferenciação de Crescimento/uso terapêutico , Mamíferos/metabolismo , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR , Neoplasias de Mama Triplo Negativas/patologia
3.
Arch Toxicol ; 97(6): 1753-1764, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36995427

RESUMO

Carbamazepine (CBZ, an antiepileptic) is metabolized by multiple CYP enzymes to its epoxide and hydroxides; however, whether it is genotoxic remains unclear. In this study, molecular docking (CBZ to CYPs) and cytogenotoxic toxicity assays were employed to investigate the activation of CBZ for mutagenic effects, in various mammalian cell models. Docking results indicated that CBZ was valid as a substrate of human CYP2B6 and 2E1, while not for CYP1A1, 1A2, 1B1 or 3A4. In the Chinese hamster (V79) cell line and its derivatives genetically engineered for the expression of human CYP1A1, 1A2, 1B1, 2E1 or 3A4 CBZ (2.5 ~ 40 µM) did not induce micronucleus, while in human CYP2B6-expressing cells CBZ significantly induced micronucleus formation. In a human hepatoma C3A cell line, which endogenously expressed CYP2B6 twofold higher than in HepG2 cells, CBZ induced micronucleus potently, which was blocked by 1-aminobenzotriazole (inhibitor of CYPs) and ticlopidine (specific CYP2B6 inhibitor). In HepG2 cells CBZ did not induce micronucleus; however, pretreatment of the cells with CICTO (CYP2B6 inducer) led to micronucleus formation by CBZ, while rifampicin (CYP3A4 inducer) or PCB126 (CYP1A inducer) did not change the negative results. Immunofluorescent assay showed that CBZ selectively induced centromere-free micronucleus. Moreover, CBZ induced double-strand DNA breaks (γ-H2AX elevation, by Western blot) and PIG-A gene mutations (by flowcytometry) in C3A (threshold being 5 µM, lower than its therapeutic serum concentrations, 17 ~ 51 µM), with no effects in HepG2 cells. Clearly, CBZ may induce clastogenesis and gene mutations at its therapeutic concentrations, human CYP2B6 being a major activating enzyme.


Assuntos
Citocromo P-450 CYP1A1 , Neoplasias Hepáticas , Cricetinae , Animais , Humanos , Citocromo P-450 CYP2B6/genética , Citocromo P-450 CYP1A1/genética , Simulação de Acoplamento Molecular , Sistema Enzimático do Citocromo P-450/metabolismo , Carbamazepina/farmacologia , Mutação , Cricetulus , Dano ao DNA
4.
J Appl Toxicol ; 42(7): 1192-1204, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35032049

RESUMO

As a serious infectious disease, tuberculosis threatens global public health. Isoniazid is the first-line drug not only in active tuberculosis but also in its prevention. Severe hepatotoxicity greatly limits its use. Curcumin, extracted from turmeric, has been found to relieve isoniazid-induced hepatotoxicity. However, the mechanism of isoniazid-induced hepatotoxicity and the protective effects of curcumin are not yet understood completely. We established both cell and animal models about isoniazid-induced hepatotoxicity and investigated the new mechanism of curcumin against isoniazid-induced liver injury. The experimental data in our study demonstrated that curcumin ameliorated isoniazid-mediated liver oxidative stress. The protective effects of curcumin were demonstrated and confirmed to be correlated with upregulating SIRT1/PGC-1α/NRF1 pathway. Western blot revealed that while inhibiting SIRT1 by the siRNA1 (a SIRT1 inhibitor), the expressions of SIRT1, PGC-1α/Ac-PGC-1α, and NRF1 decreased, and the protective effect that curcumin exerted on isoniazid-treated L-02 cells was significantly attenuated. Furthermore, curcumin improved liver functions and reduced necrosis of the isoniazid-treated BALB/c mice, accompanied by downregulating oxidative stress and inflammation in liver. Western blot revealed that curcumin treatment activates the SIRT1/PGC-1α/NRF1 pathway in the isoniazid-treated BALB/c mice. In conclusion, we found one mechanism of isoniazid-induced hepatotoxicity downregulating the SIRT1/PGC-1α/NRF1 pathway, and curcumin attenuated this hepatotoxicity by activating it. Our study provided a novel approach and mechanism for the treatment of isoniazid-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Curcumina , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Curcumina/metabolismo , Curcumina/farmacologia , Isoniazida/toxicidade , Camundongos , Mitocôndrias , Estresse Oxidativo , Sirtuína 1/genética , Sirtuína 1/metabolismo
5.
J Appl Toxicol ; 42(3): 516-528, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34494278

RESUMO

Isoniazid (INH)-induced liver injury is a great challenge for tuberculosis treatment. Existing biomarkers cannot accurately determine the occurrence of this injury in the early stage. Therefore, developing early specific sensitive biomarkers of INH-induced liver injury is urgent. A rat model of liver injury was established with gastric infusion of INH or INH plus rifampicin (RFP). We examined seven potential novel serum biomarkers, namely, glutamate dehydrogenase (GLDH), liver-fatty acid-binding protein (L-FABP), high-mobility group box-1 (HMGB1), macrophage colony-stimulating factor receptor (MCSF1R), osteopontin (OPN), total cytokeratin 18 (K18), and caspase-cleaved cytokeratin-18 (ccK18), to evaluate their sensitivity and specificity on INH-induced liver injury. With the increase of drug dosage, combining with RFP and prolonging duration of administration, the liver injury was aggravated, showing as decreased weight of the rats, upgraded liver index and oxidative stress level, and histopathological changes of liver becoming marked. But the activity of serum aminotransferases decreased significantly. The area under the curve (AUC) of receiver-operating characteristic (ROC) curve of OPN, L-FABP, HMGB1, MCSF1R, and GLDH was 0.88, 0.87, 0.85, 0.71, and 0.70 (≥0.7), respectively, and 95% confidence interval of them did not include 0.5, with statistical significance, indicating their potential abilities to become biomarkers of INH-induced liver injury. In conclusion, we found traditional biomarkers ALT and AST were insufficient to discover the INH-induced liver injury accurately and OPN, L-FABP, and HMGB1 can be promising novel biomarkers.


Assuntos
Antituberculosos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Proteínas de Ligação a Ácido Graxo/sangue , Proteína HMGB1/sangue , Isoniazida/toxicidade , Osteopontina/sangue , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Transaminases/sangue
6.
Urol Int ; 106(9): 869-877, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34518476

RESUMO

INTRODUCTION: The aim of this article was to investigate the relationship between statins and the risk of different stages or grades of prostate cancer. METHODS: A comprehensive literature search was performed for articles published until December 18, 2020, on the PubMed, Embase, and the Cochrane Library databases. The pooled relative risk (RR) and 95% confidence interval (CI) were then analyzed using the STATA.16.0 software. RESULTS: A total of 588,055 patients from 14 studies were included in the analysis. We found that the use of statins expressed a significant correlation with a lower risk of advanced prostate cancer (RR = 0.81, 95% CI: 0.73-0.91; RR = 0.86, 95% CI: 0.75-0.99, respectively). However, no evidence suggested that the use of statins was beneficial for the prevention of localized prostate cancer incidence. Similarly, the pooled results also revealed no association between the use of statins and the risk of high-grade and low-grade prostate cancer. CONCLUSION: It has been found that the use of statins is associated with a lower risk of advanced prostate cancer but was not related to the risk of localized, low-grade, or high-grade prostate cancer.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias da Próstata , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Incidência , Masculino , Próstata , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/prevenção & controle , Risco
7.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36361935

RESUMO

The large-scale production and frequent use of endocrine-disrupting chemicals (EDCs) have led to the continuous release and wide distribution of these pollutions in the natural environment. At low levels, EDC exposure may cause metabolic disorders, sexual development, and reproductive disorders in aquatic animals and humans. Adsorption treatment, particularly using nanocomposites, may represent a promising and sustainable method for EDC removal from wastewater. EDCs could be effectively removed from wastewater using various carbon-based nanomaterials, such as carbon nanofiber, carbon nanotubes, graphene, magnetic carbon nanomaterials, carbon membranes, carbon dots, carbon sponges, etc. Important applications of carbon nanocomposites for the removal of different kinds of EDCs and the theory of adsorption are discussed, as well as recent advances in carbon nanocomposite synthesis technology and characterization technology. Furthermore, the factors affecting the use of carbon nanocomposites and comparisons with other adsorbents for EDC removal are reviewed. This review is significant because it helps to promote the development of nanocomposites for the decontamination of wastewater.


Assuntos
Disruptores Endócrinos , Nanocompostos , Nanotubos de Carbono , Poluentes Químicos da Água , Animais , Humanos , Disruptores Endócrinos/química , Águas Residuárias/química , Adsorção
8.
Molecules ; 27(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35566160

RESUMO

Chemicals underlying the floral aroma of dry teas needs multi-dimensional investigations. Green, black, and freeze-dried tea samples were produced from five tea cultivars, and only 'Chunyu2' and 'Jinguanyin' dry teas had floral scents. 'Chunyu2' green tea contained the highest content of total volatiles (134.75 µg/g) among green tea samples, while 'Jinguanyin' black tea contained the highest content of total volatiles (1908.05 µg/g) among black tea samples. The principal component analysis study showed that 'Chunyu2' and 'Jinguanyin' green teas and 'Chunyu2' black tea were characterized by the abundant presence of certain alcohols with floral aroma, while 'Jinguanyin' black tea was discriminated due to the high levels of certain alcohols, esters, and aldehydes. A total of 27 shared volatiles were present in different tea samples, and the contents of 7 floral odorants in dry teas had correlations with those in fresh tea leaves (p < 0.05). Thus, the tea cultivar is crucial to the floral scent of dry tea, and these seven volatiles could be promising breeding indices.


Assuntos
Camellia sinensis , Compostos Orgânicos Voláteis , Álcoois/análise , Camellia sinensis/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Melhoramento Vegetal , Chá/química , Compostos Orgânicos Voláteis/análise
9.
Int J Clin Pharmacol Ther ; 57(10): 520-530, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31262398

RESUMO

OBJECTIVE: To characterize the pharmacokinetics of trazodone hydrochloride (HCl) sustained-release tablets (TSR) and trazodone immediate-release formulation (TIR) and investigate the effects of food on the pharmacokinetics of the drug in healthy subjects. MATERIALS AND METHODS: Three open-label, randomized crossover trials of single-dose, multiple-dose, and food-drug interaction testing were conducted. A validated high-performance liquid chromatography-fluorescence method was used to measure the plasma concentration of trazodone, and a non-compartment model was used to obtain the pharmacokinetic parameters. AUC and Cmax dose proportionality were analyzed using a power model. RESULTS: TSR lacked dose proportionality over a dose range of 25 - 150 mg. In the food-drug interaction study, no significant changes in the pharmacokinetic parameters of the drug under the fed conditions were observed. Multiple dosage of TSR and TIR reached steady state after 7 days, with no accumulation phenomenon observed. The peak time and peak concentrations of TSR were significantly longer and lower, respectively, than those of TIR. CONCLUSION: TSR showed clear sustained-release characteristics, and food exhibited no significant effects on the pharmacokinetic parameters of trazodone. TSR and TIR reached steady state levels after 7 consecutive days of administration, with no accumulation phenomenon observed.


Assuntos
Preparações de Ação Retardada/farmacocinética , Trazodona/farmacocinética , Área Sob a Curva , Estudos Cross-Over , Interações Alimento-Droga , Humanos , Comprimidos
10.
Nano Lett ; 18(7): 4200-4205, 2018 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-29911870

RESUMO

Through-bond conjugated molecules are the major frameworks for traditional molecular wires, while through-space conjugated units are rarely utilized and studied although they have shown unique conducting potential. Herein, we present novel single-molecule wires built on through-space conjugated hexaphenylbenzene. Their conductance, measured by the scanning tunneling microscopy based break-junction technique, increases with the improvement of through-space conjugation and finally reaches a remarkable value (12.28 nS) which greatly exceeds that of conventional through-bond conjugated counterpart (2.45 nS). The multichannel conducting model by integrating through-space and through-bond conjugations could be a promising strategy for the further design of robust single-molecule wires with advanced conductance and stability.

11.
Cell Physiol Biochem ; 46(4): 1536-1554, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29689560

RESUMO

BACKGROUND/AIMS: This study determined the role and mechanism of action of transcription factor EB (TFEB) in H2O2-induced neuronal apoptosis. METHODS: SH-SY5Y cells were treated with Akt inhibitor/activator and different concentrations of H2O2. Cell apoptosis was detected by flow cytometric analysis. Akt and TFEB phosphorylation and PARP cleavage were determined by Western blotting. HEK293T cells were transfected with different truncated TFEB mutants and HA-Akt-WT; SH-SY5Y cells were transfected with Flag-vector, Flag-TFEB, Flag-TFEB-S467A or Flag-TFEB-S467D; and TFEB interaction with Akt was determined by co-immunoprecipitation and GST pull-down assays. RESULTS: A low concentration of H2O2 induces TFEB phosphorylation at Ser467 and nuclear translocation, facilitating neuronal survival, whereas a high concentration of H2O2 promotes SH-SY5Y cell apoptosis via suppressing TFEB Ser467 phosphorylation and nuclear translocation. The TFEB-S467D mutant is more easily translocated into the nucleus than the non-phosphorylated TFEB-S467A mutant. Further, Akt physically binds to TFEB via its C-terminal tail interaction with the HLH domain of TFEB and phosphorylates TFEB at Ser467. Mutation of TFEB-Ser467 can prevent the phosphorylation of TFEB by Akt, preventing inhibition of oxidative stress-induced apoptosis. CONCLUSIONS: Oxidative stress induces neuronal apoptosis through suppressing TFEB phosphorylation at Ser467 by Akt, providing a novel therapeutic strategy for neurodegenerative diseases.


Assuntos
Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Androstadienos/farmacologia , Animais , Linhagem Celular Tumoral , Flavonoides/farmacologia , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Neurônios/citologia , Neurônios/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Wortmanina
12.
Chemistry ; 23(71): 18041-18048, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-28985454

RESUMO

Through-space conjugation is an important noncovalent interaction in artificial materials and biomacromolecules. Establishing relationships between geometry and property is of high significance to provide deeper insights into this phenomenon. In this work, we have focused on the through-space conjugation in a new class of foldamers with a folded tetraphenylethene core. We have studied its impact on the photophysical properties through experimental measurements and theoretical calculations. It is found that the through-space conjugation makes significant contributions to the short-wavelength absorption in these foldamers. Moreover, these foldamers exhibit aggregation-enhanced emission (AEE) and apparent blue shifts in their emission spectra on going from solution to aggregates. The structural changes are smaller in the aggregated state than those in the isolated state during the excited-state relaxation process, which results in lower re-organization energies. This accounts for the blueshifted and enhanced emissions in the aggregates.

13.
Case Rep Oncol ; 17(1): 430-437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38449876

RESUMO

Introduction: Mature cystic teratoma (MCT) is a common type of ovarian tumors that can, in rare cases, undergo malignant transformation. It has been discovered that MCT patients may experience psychiatric symptoms due to the presence of anti-N-methyl-D-aspartate receptor (NMDAR) antibodies, which is the underlying cause of autoimmune encephalitis. Here, we present the first documented case of a patient with anti-NMDAR encephalitis who also had a morphology of low-grade glioma within MCT. Case Report: A 45-year-old woman presented with seizures, altered consciousness, abnormal NMDAR antibody IgG titers, and abnormal brain MRI findings confirm the diagnosis of anti-NMDAR encephalitis. Physical examination revealed an oval mixed echo mass measuring 54 × 37 mm in the left adnexal area on ultrasound of the uterine appendage. The patient underwent laparoscopic left ovarian and fallopian tube resection. The pathological gross examination revealed a pile of grayish-red cystic and solid fragmented tissue measuring 7 × 6 × 2.2 cm. Histological examination revealed characteristic components of MCT. Furthermore, the solid component of the gross tissue showed proliferative and densely arranged astrocytes with cellular atypia, which were positive for GFAP and Olig-2, negative for IDH1 and EMA. And the Ki67 index was approximately 10%, suggesting the presence of low-grade glioma lesions. The patient was diagnosed with malignant transformation of MCT into a morphology of low-grade glioma, not otherwise specified. After the removal of the ovarian tumor, the patient's psychiatric symptoms improved. Conclusions: Low-grade glioma within MCT is a rare occurrence, and the presence of this malignant transformation in patients with anti-NMDAR encephalitis is even more uncommon.

14.
Chem Biol Interact ; 397: 111088, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823534

RESUMO

Tris(2-butoxyethyl) phosphate (TBOEP) is an organophosphorus flame retardant ubiquitously present in the environment and even the human body. TBOEP is toxic in multiple tissues, which forms dealkylated and hydroxylated metabolites under incubation with human hepatic microsomes; however, the impact of TBOEP metabolism on its toxicity, particularly mutagenicity (typically requiring metabolic activation), is left unidentified. In this study, the mutagenicity of TBOEP in human hepatoma cell lines (HepG2 and C3A) and the role of specific CYPs were studied. Through molecular docking, TBOEP bound to human CYP1A1, 1B1, 2B6 and 3A4 with energies and conformations favorable for catalyzing reactions, while the conformations of its binding with human CYP1A2 and 2E1 appeared unfavorable. In C3A cells (endogenous CYPs being substantial), TBOEP exposing for 72 h (2-cell cycle) at low micromolar levels induced micronucleus, which was abolished by 1-aminobenzotriazole (inhibitor of CYPs); in HepG2 cells (CYPs being insufficient) TBOEP did not induce micronucleus, whose effect was however potentiated by pretreating the cells with PCB126 (CYP1A1 inducer) or rifampicin (CYP3A4 inducer). TBOEP induced micronucleus in Chinese hamster V79-derived cell lines genetically engineered for stably expressing human CYP1A1 and 3A4, but not in cells expressing the other CYPs. In C3A cells, TBOEP selectively induced centromere protein B-free micronucleus (visualized by immunofluorescence) and PIG-A gene mutations, and elevated γ-H2AX rather than p-H3 (by Western blot) which indicated specific double-strand DNA breaks. Therefore, this study suggests that TBOEP may induce DNA/chromosome breaks and gene mutations in human cells, which requires metabolic activation by CYPs, primarily CYP1A1 and 3A4.


Assuntos
Sistema Enzimático do Citocromo P-450 , Retardadores de Chama , Simulação de Acoplamento Molecular , Animais , Humanos , Retardadores de Chama/toxicidade , Cricetinae , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Mutagênicos/toxicidade , Compostos Organofosforados/toxicidade , Cricetulus , Organofosfatos/toxicidade , Células Hep G2 , Testes para Micronúcleos
15.
Toxicology ; 504: 153774, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38490321

RESUMO

N-nitrosonornicotine (NNN) and N-nitrosoanabasine (NAB) are both tobacco-specific nitrosamines bearing two heterocyclic amino groups, NAB bearing an extra -CH2- group (conferring a hexa- rather than penta-membered cycle) but with significantly decreased carcinogenicity. However, their activating enzymes and related mutagenicity remain unclear. In this study, the chemical-CYP interaction was analyzed by molecular docking, thus the binding energies and conformations of NNN for human CYP2A6, 2A13, 2B6, 2E1 and 3A4 appeared appropriate as a substrate, so did NAB for human CYP1B1, 2A6, 2A13 and 2E1. The micronucleus test in human hepatoma (HepG2) cells with each compound (62.5-1000 µM) exposing for 48 h (two-cell cycle) was negative, however, pretreatment with bisphenol AF (0.1-100 nM, CYPs inducer) and ethanol (0.2% v:v, CYP2E1 inducer) potentiated micronucleus formation by both compounds, while CITCO (1 µM, CYP2B6 inducer) selectively potentiated that by NNN. In C3A cells (endogenous CYPs enhanced over HepG2) both compounds induced micronucleus, which was abolished by 1-aminobenzotriazole (60 µM, CYPs inhibitor) while unaffected by 8-methoxypsoralen (1 µM, CYP2A inhibitor). Consistently, NNN and NAB induced micronucleus in V79-derived recombinant cell lines expressing human CYP2B6/2E1 and CYP1B1/2E1, respectively, while negative in those expressing other CYPs. By immunofluorescent assay both compounds selectively induced centromere-free micronucleus in C3A cells. In PIG-A assays in HepG2 cells NNN and NAB were weakly positive and simply negative, respectively; however, in C3A cells both compounds significantly induced gene mutations, NNN being slight more potent. Conclusively, both NNN and NAB are mutagenic and clastogenic, depending on metabolic activation by partially different CYP enzymes.


Assuntos
Sistema Enzimático do Citocromo P-450 , Testes para Micronúcleos , Nitrosaminas , Humanos , Nitrosaminas/toxicidade , Nitrosaminas/metabolismo , Células Hep G2 , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Simulação de Acoplamento Molecular , Mutagênicos/toxicidade , Nicotiana
16.
Ying Yong Sheng Tai Xue Bao ; 35(5): 1177-1186, 2024 May.
Artigo em Zh | MEDLINE | ID: mdl-38886415

RESUMO

The radial growth of trees in alpine timberline is particularly sensitive to climate change. We sampled and disposed tree-ring cores of three coniferous tree species including Juniperus saltuaria, Abies forrestii, and Larix potaninii at alpine timberline in Yading Nature Reserve. The standard tree-ring chronology was used to explore the response of radial growth of different timberline species to climate change. The results showed that radial growth of L. potaninii increased after 2000, while that of A. forrestii declined after 2002, and J. saltuaria showed a significant decreasing growth trend in the past 10 years. Such results indicated divergent growth responses to climate factors among the three tree species at alpine timberline. The radial growth of J. saltuaria was sensitive to temperature, and was positively correlated with the minimum temperature from previous October to current August, the mean tempera-ture from previous November to current April and from current July to October, but was negatively associated with the relative humidity from current July to October. The radial growth of A. forrestii showed negative correlation with mean temperature and the maximum temperature from May to June in the current year, while it exhibited positive association with the relative humidity and the Palmer drought severity index from May to June in the current year. L. potaninii radial growth was positively associated with mean temperature and the maximum temperature of November-December in the previous year, the maximum temperature of current March and mean temperature of current August. The temporal stability of climate-growth relationship varied among different timberline species. The positive correlation between radial growth of A. forrestii and J. saltuaria and temperature gradually decreased, while the posi-tive relationship of L. potaninii radial growth and temperature gradually increased. Under the background of climate warming, rapid rise in surface air temperatures may promote the radial growth of L. potaninii, while inhibit that of J. saltuaria and A. forrestii, which may change the position of regional timberline.


Assuntos
Mudança Climática , Larix , China , Larix/crescimento & desenvolvimento , Juniperus/crescimento & desenvolvimento , Abies/crescimento & desenvolvimento , Ecossistema , Árvores/crescimento & desenvolvimento , Conservação dos Recursos Naturais , Temperatura , Caules de Planta/crescimento & desenvolvimento , Altitude
17.
Ultrason Sonochem ; 95: 106369, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36965313

RESUMO

The purpose of this study was to investigate effect of physical treatment (ultrasound, U/high pressure homogenization, H/combined treatment, UH or HU) and surfactant (Mogroside V, Mog) on air/water interface adsorption and foaming properties of α-lactalbumin (ALa). Firstly, the binding of Mog and all physical-treated ALa was a static quenching process. Mog had the greatest binding affinity for HU-ALa among all treated samples. U or H treatment could change surface hydrophobicity of ALa/Mog complex. Secondly, at the molar ratio (ALa:Mog) of 1:50, foaming ability (FA) of all ALa samples got the maximum. The sequence of FA in ALa and ALa/Mog complex was listed as follow: HU > U > H > UH. Moreover, foaming stability (FS) of HU-ALa was the highest, followed by H-ALa, U-ALa and UH-ALa. Meanwhile, low concentration Mog increased FS of ALa or UH-ALa, but it reduced FS of H-ALa, U-ALa and HU-ALa. Quartz crystal microbalance with dissipation monitoring (QCM-D) experiment indicated that ALa/Mog complex after U or H treatment was quickly absorbed at air/water interface, compared with the treated ALa, and HU-ALa/Mog had the largest frequency shift. In addition, HU-ALa had the thickest bubble membrane and the highest dissipation shift in all samples, indicating that the absorbed membrane thickness and viscoelasticity of samples was correlated with foam stability. Therefore, U and H treatment synergism with Mog was an effective approach to enhance foam properties of ALa, which indicated that HU-treated ALa/Mog complex could be viewed as the safe and efficient foaming agent applied in food processing.


Assuntos
Lactalbumina , Tensoativos , Lactalbumina/química , Água/química
18.
ACS Appl Mater Interfaces ; 15(28): 34044-34054, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37401777

RESUMO

Solar-driven interfacial evaporation (SDIE) with excellent photothermal conversion efficiency is emerging as one of the frontier technologies for freshwater production. In this work, novel carbonized conjugate microporous polymers (CCMPs) hollow microspheres-based composite hydrogel membranes (CCMPsHM-CHM) for efficient SDIE are reported. The precursor, CMPs hollow microspheres (CMPsHM), is synthesized by an in situ Sonogashira-Hagihara cross-coupling reaction using a hard template method. The as-synthesized CCMPsHM-CHM exhibit significantly excellent properties, i.e., 3D hierarchical architecture (from micropore to macropore), superior solar light absorption (more than 89%), better thermal insulation (thermal conductivity as low as 0.32-0.42 W m-1K-1 in the wet state), superhydrophilic wettability with a water contact angle (WCA) of 0°, superior solar efficiency (up to 89-91%), a high evaporation rate of 1.48-1.51 kg m-2 h-1 under 1 sun irradiation, and excellent stability which maintains an evaporation rate of more than 80% after 10 cycles and over 83% evaporation efficiency in highly concentrated brine. In this case, the removal rate of metal ions in seawater is more than 99%, which is much lower than the ion concentration standard for drinking water set by the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA). Taking advantage of its simple and scalable manufacture, our CCMPsHM-CHM may have great potential as advanced membranes for various applications for efficient SDIE in different environments.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37890048

RESUMO

Solar-driven interfacial evaporation co-generation (SIE-CG) technology is of great significance in solving the problem of water and energy shortage. Herein, we report the ionic liquid-assisted alignment of waste biomass tea residue-based microcrystalline cellulose for aerogels (abbreviated as TPPA-5) with aligned channels for solar-driven interfacial evaporation co-generation. In the ionic liquid, strong H-bonding is formed between the pyranoid rings of cellulose combined with the slow freezing technique, resulting in the microcrystalline cellulose being reoriented, which allowed TPPA-5 to form abundant aligned channels after solvent replacement and freeze-drying. These aligned channels enable the brine to form a localized circulating flow, which is conducive to the improvement of the TPPA's evaporation rate and salt resistance. The salinity gradient is naturally formed in the channel of TPPA, which enables TPPA-5 to show excellent power generation performance. The evaporation rate of TPPA-5 can reach 3.39 kg m-2 h-1 under 1 kW m-2. With methanol as a highly polar proton solvent, the maximum output voltage obtained was 67.534 mV due to the overlapping electric double-layer effect formed by hydrogen protons on the TPPA surface, and the energy utilization efficiency is 95.95%. Moreover, TPPA-5 can purify pesticide-containing wastewater, which has the advantages of being recyclable and environmentally friendly, showing potential application value in the field of seawater desalination and steam co-generation.

20.
Artigo em Zh | MEDLINE | ID: mdl-22808548

RESUMO

OBJECTIVE: To explore the main pathogenic factor causing the peptic ulcer of taxi drivers, which provide the basis for its prevention. METHODS: 98 taxi drivers were inspected by electronic endoscopy, according to the inspection all cases were divided into ulcers group and normal group. Then various factors were statuses by the logistic regression analysis according to the results of questionnaire. RESULTS: The prevalence of peptic ulcer of taxi drivers was 52.0%, and logistic regression analysis showed that dining time, taste spicy, meals temperature, smoking,alcohol, mental stress, HP infection and stomach health knowledge were statistically significant (P < 0.05), which would be the risk factors for peptic ulcer of taxi drivers. CONCLUSION: By emphasis on diet and lifestyle adjustments, stress regulation on the basis of eradication of HP infection will help the prevention and treatment of peptic ulcer of the taxi driver.


Assuntos
Condução de Veículo , Doenças Profissionais/epidemiologia , Úlcera Péptica/epidemiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
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