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1.
Nat Commun ; 12(1): 867, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558520

RESUMO

Statins are effective cholesterol-lowering drugs. Lovastatin, one of the precursors of statins, is formed from dihydromonacolin L (DML), which is synthesized by lovastatin nonaketide synthase (LovB), with the assistance of a separate trans-acting enoyl reductase (LovC). A full DML synthesis comprises 8 polyketide synthetic cycles with about 35 steps. The assembling of the LovB-LovC complex, and the structural basis for the iterative and yet permutative functions of the megasynthase have remained a mystery. Here, we present the cryo-EM structures of the LovB-LovC complex at 3.60 Å and the core LovB at 2.91 Å resolution. The domain organization of LovB is an X-shaped face-to-face dimer containing eight connected domains. The binding of LovC laterally to the malonyl-acetyl transferase domain allows the completion of a L-shaped catalytic chamber consisting of six active domains. This architecture and the structural details of the megasynthase provide the basis for the processing of the intermediates by the individual catalytic domains. The detailed architectural model provides structural insights that may enable the re-engineering of the megasynthase for the generation of new statins.


Assuntos
Lovastatina/biossíntese , Lovastatina/química , Biocatálise , Modelos Moleculares , Naftalenos/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/química , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Policetídeo Sintases/química , Policetídeo Sintases/metabolismo , Policetídeo Sintases/ultraestrutura , Domínios Proteicos , Especificidade por Substrato
2.
Water Sci Technol ; 83(2): 257-270, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33504692

RESUMO

This paper presents a study of V and N co-doping TiO2 embedding multi-walled carbon nanotubes (MWCNTs) supported on γ-Al2O3 pellet (V/N-TiO2-MWCNTs/γ-Al2O3) composite photocatalyst induced by pulsed discharge plasma to enhance the removal of acid orange II (AO7) from aqueous solution. The photocatalytic activity of the V/N-TiO2-MWCNTs/γ-Al2O3 composite to AO7 removal induced by the pulsed discharge plasma was evaluated. The results indicate that the V/N-TiO2-MWCNTs/γ-Al2O3 composite possesses enhanced photocatalytic activity that facilitates the removal of AO7 compared with the TiO2-MWCNTs/γ-Al2O3 and TiO2/γ-Al2O3 composites. Almost 100% of AO7 is removed after 10 min under optimal conditions. The V0.10/N0.05-TiO2-MWCNTs/γ-Al2O3 photocatalyst exhibits the best removal effect for AO7. Analysis of the removal mechanism indicates that the enhancement of the removal of AO7 resulting from V and N co-doping causes TiO2 lattice distortion and introduces a new impurity energy level, which not only reduces the band gap of TiO2 but also inhibits the recombination of the ecb-/hvb+ pairs.


Assuntos
Nanotubos de Carbono , Compostos Azo , Catálise , Naftalenos , Plasma , Titânio
3.
Ecotoxicol Environ Saf ; 210: 111880, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421721

RESUMO

The coal pyrolysis wastewater (CPW) contributed to aquatic environment contamination with amount of aromatic pollutants, and the research on joint toxicity of the mixture of aromatic compounds was vital for environmental protection. By using Tetrahymena thermophile as non-target organism, the joint toxicity of typical nonpolar narcotics and polar narcotics in CPW was investigated. The results demonstrated that the nonpolar narcotics exerted chronic and reversible toxicity by hydrophobicity-based membrane perturbation, while polar narcotics performed acute toxicity by irreversible damage of cells. As the most hydrophobic nonpolar narcotics, indole and naphthalene caused the highest joint toxicity in 24 h with the lowest EC50mix (24.93 mg/L). For phenolic compounds, the combination of p-cresol and p-nitrophenol also showed the top toxicity (EC50mix = 10.9 mg/L) with relation to high hydrophobicity, and the joint toxicity was obviously stronger and more acute than that of nonpolar narcotics. Furthermore, by studying the joint toxicity of nonpolar narcotics and polar narcotics, the hydrophobicity-based membrane perturbation was the first step of toxicity effects, and afterwards the acute toxicity induced by electrophilic polar substituents of phenols dominated joint toxicity afterwards. This toxicity investigation was critical for understanding universal and specific effects of CPW to aquatic organisms.


Assuntos
Carvão Mineral , Pirólise , Tetrahymena/efeitos dos fármacos , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade , Indóis/toxicidade , Naftalenos/toxicidade , Entorpecentes/toxicidade , Fenóis/toxicidade
4.
Medicina (Kaunas) ; 57(1)2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33435164

RESUMO

This article aims to critically review the evidence on the available therapeutic strategies for the treatment of hyperuricemia. For this reason, several papers were reviewed. Xanthine oxidase inhibitors are the safest and most effective uric acid lowering drugs for the management of chronic hyperuricemia, while the efficacy of uricosuric agents is strongly modulated by pharmacogenetics. Emergent drugs (lesinurad, peglotidase) were found to be more effective for the acute management of refractory hyperuricemia, but their use is supported by a relatively small number of clinical trials so that further well-designed clinical research is needed to deepen their efficacy and safety profile.


Assuntos
Hiperuricemia/tratamento farmacológico , Uricosúricos/uso terapêutico , Xantina Oxidase/antagonistas & inibidores , Acetamidas/uso terapêutico , Alopurinol/uso terapêutico , Benzobromarona/uso terapêutico , Doença Crônica , Medicina Baseada em Evidências , Febuxostat/uso terapêutico , Supressores da Gota/uso terapêutico , Humanos , Naftalenos/uso terapêutico , Nitrilos/uso terapêutico , Fenilacetatos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Probenecid/uso terapêutico , Propionatos/uso terapêutico , Piridinas/uso terapêutico , Tioglicolatos/uso terapêutico , Triazóis/uso terapêutico , Urato Oxidase/uso terapêutico
5.
Anal Chem ; 93(5): 2767-2775, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33474935

RESUMO

Clinical tissue specimens are often unscreened, and preparation of tissue sections for analysis by mass spectrometry imaging (MSI) can cause aerosolization of particles potentially carrying an infectious load. We here present a decontamination approach based on ultraviolet-C (UV-C) light to inactivate clinically relevant pathogens such as herpesviridae, papovaviridae human immunodeficiency virus, or SARS-CoV-2, which may be present in human tissue samples while preserving the biodistributions of analytes within the tissue. High doses of UV-C required for high-level disinfection were found to cause oxidation and photodegradation of endogenous species. Lower UV-C doses maintaining inactivation of clinically relevant pathogens to a level of increased operator safety were found to be less destructive to the tissue metabolome and xenobiotics. These doses caused less alterations of the tissue metabolome and allowed elucidation of the biodistribution of the endogenous metabolites. Additionally, we were able to determine the spatially integrated abundances of the ATR inhibitor ceralasertib from decontaminated human biopsies using desorption electrospray ionization-MSI (DESI-MSI).


Assuntos
Descontaminação/métodos , Raios Ultravioleta , Animais , Azetidinas/análise , Azetidinas/uso terapêutico , /virologia , Neoplasias de Cabeça e Pescoço/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Metaboloma , Naftalenos/análise , Naftalenos/uso terapêutico , Fotólise/efeitos da radiação , Ratos , Ratos Wistar , /efeitos da radiação , Espectrometria de Massas por Ionização por Electrospray/métodos , Terfenadina/química , Inativação de Vírus/efeitos da radiação
6.
Chemosphere ; 263: 127987, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32835980

RESUMO

The high value-added use of tannery solid waste and elimination of tannery liquid waste in the leather-making industry have attracted widespread attention. In this study, a MgO-doped biochar (MgO/BC) adsorbent was successfully prepared by utilizing tannery solid waste (i.e., non-tanned hide wastes) as the biomass material for dye removal from tannery wastewater. Characterization results indicated that MgO was uniformly embedded into the porous BC structure. The adsorption capacity of acid orange II by MgO/BC reached up to 448.4 mg g-1, which drastically exceeded the pure BC and other reported adsorbents. The adsorption behavior of acid orange II by MgO/BC matched nicely with Langmuir isotherm and pseudo-second-order kinetic model. This satisfactory adsorption capacity of MgO/BC for acid orange II was mainly due to the large specific surface area and the enhanced electrostatic interaction. According to the BET, zeta potential and XPS analysis, the possible mechanism towards acid orange II removal was attributed to the pore filling, surface complexation, electrostatic attraction and π-π interaction. In addition, MgO/BC showed the efficient removal towards anionic dyes from actual tannery wastewater. This work could provide guidance for the value-added utilization of tannery solid waste and a practical way to remove dyes from tannery wastewater.


Assuntos
Corantes/análise , Curtume , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Adsorção , Compostos Azo , Carvão Vegetal , Cinética , Naftalenos , Resíduos Sólidos , Águas Residuárias/química
7.
Aquat Toxicol ; 231: 105710, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338701

RESUMO

The co-contamination of naphthalene (NAP) and microcystin-LR (MC-LR) commonly occurs in eutrophic waters. However, the joint effects of NAP and MC-LR on plants in aquatic environments remain unknown. Landoltia punctata is characterized by high starch yields and high biomass in polluted waters and has been proven to be a bioenergy crop and phytoremediation plant. In this study, L. punctata was cultured in a nutrient medium with environmentally relevant NAP (0.1, 1, 3, 5, and 10 µg/L) and MC-LR (5, 10, 25, 50, and 100 µg/L) to determine individual and joint toxic effects. The effects of NAP and MC-LR on physiological responses of L. punctata, including growth, starch accumulation, and antioxidant responses, were studied. Bioaccumulation of MC-LR in L. punctata, with or without NAP, was also examined. The results showed that growth and chlorophyll-a contents of L. punctata were reduced at high concentrations of MC-LR (≥ 25 µg/L), NAP (≥ 10 µg/L) and their mixture (≥ 10 + 1 µg/L) after exposure for 7 d. Starch accumulation in L. punctata did not decrease when exposed to NAP and MC-LR, and higher starch content of 29.8 % ± 2.7 % DW could be due to the destruction of starch-degrading enzymes. The antioxidant responses of L. punctata were stronger after exposure to MC-LR + NAP than when exposed to a single pollutant, although not enough to avoid oxidative damage. NAP enhanced the bioaccumulation of MC-LR in L. punctata when NAP concentration was higher than 5 µg/L, suggesting that higher potentials of MC-LR phytoremediation with L. punctata may be observed in NAP and MC-LR co-concomitant waters. This study provides theoretical support for the application of duckweed in eutrophic waters containing organic chemical pollutants.


Assuntos
Araceae/fisiologia , Toxinas Marinhas/toxicidade , Microcistinas/toxicidade , Naftalenos/toxicidade , Antioxidantes/metabolismo , Araceae/efeitos dos fármacos , Araceae/crescimento & desenvolvimento , Bioacumulação/efeitos dos fármacos , Biodegradação Ambiental , Biomassa , Modelos Biológicos , Fenótipo , Amido/metabolismo , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade
8.
Chemosphere ; 263: 127963, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297024

RESUMO

In this work, the performance of the atmospheric pressure chemical ionization (APCI) and photoionization (APPI) was assessed to develop a new selective and sensitive gas chromatography-high resolution mass spectrometry (GC-HRMS) method for the determination of polychlorinated naphthalenes (PCNs) in sediment samples. The capability of both APCI and APPI sources for the ionization of PCNs was investigated, showing the formation of the molecular ion and the [M‒Cl+O]‒ ion in positive and negative ion modes, respectively. Positive ion APCI provided high responses using high corona ion current, while the use of high vapour pressure dopant-solvents, such as toluene in positive mode and diethyl ether in the negative mode, was required to achieve high ionization efficiencies in APPI. The performance of the two API sources in the PCN determination by GC-HRMS were compared and the best results were achieved using the GC-APPI(+)-HRMS (Orbitrap) system. The GC-APPI(+)-HRMS (Orbitrap) method was applied to the characterization of Halowax mixtures and the analysis of marine sediments collected near to the coastal area of Barcelona (NE, Spain), demonstrating a great detection capability with low method limits of detection (0.2-1.6 pg g-1 dry weight), good precision (RSD <15%) and trueness (relative error <13%). Total PCN concentrations ranged from 0.35 to 5.0 ng g-1 dry weight and the presence of related compounds, such as polychlorinated biphenyls (PCBs), was also detected by combining positive and negative ion modes, providing complementary information to better monitor of all PCN congener groups. The results presented here show the feasibility of the GC-APPI-HRMS method for the suitable determination of PCNs.


Assuntos
Pressão Atmosférica , Naftalenos , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos , Naftalenos/análise , Espanha
9.
Chemosphere ; 263: 128006, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297039

RESUMO

Many persistent organic pollutants (POPs) exhibit endocrine disrupting activity but studies on some POPs, e.g., polychlorinated naphthalenes (PCNs), are very scarce. The present study investigates the (anti)estrogenic and (anti)androgenic activities of 1,2,3,5,6,7-hexachloronaphthalane (PCN67) and 1,3,5,8-tetrachloronaphthalene (PCN43) using the yeast estrogen and androgen reporter bioassays. Among the tested substances, antiestrogenic response was only shown by PCN67. The strongest inhibition of estrogenic activity (up to 17.4%) was observed in the low concentration ranges (5 pM - 0.5 nM) in the presence of 1.5 nM 17ß-estradiol. Both tested compounds showed partial estrogenic activity with a hormetic-type response. However, both studied chemicals showed strong antiandrogenic effects: their potency in the presence of 100 nM 17ß-testosterone for PCN43 (IC50 = 2.59 µM) and PCN67 (IC50 = 3.14 µM) was approximately twice that of the reference antiandrogen flutamide (IC50 = 6.14 µM). It cannot be excluded that exposure to PCNs, together with other endocrine disrupting chemicals (EDCs), may contribute to the deregulation of sex steroid hormone signaling.


Assuntos
Androgênios , Disruptores Endócrinos , Disruptores Endócrinos/toxicidade , Estrogênios , Naftalenos
10.
Chemosphere ; 263: 128079, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297078

RESUMO

Naphthalene is the simplest representative of polycyclic aromatic hydrocarbons (PAHs). It is detected as major pollutant in the different compartments of the environment. This compound is considered by the international agency for research on cancer (IARC), the specialized cancer agency of the World Health Organisation (WHO), as a possible carcinogenic (group 2B) since 2002, mainly based on studies on chronic inhalation in rodent by the national toxicology program of the U.S. department of health and human services. In humans, its main metabolites correspond to derivatives substituted in position and 1 and 2 as 1,2-naphthoquinone (1,2-NphQ). Based on previous studies, 1,2-NphQ is supposed to react with DNA to form mostly depurinating adducts, a possible initiating step of carcinogenicity. To confirm this potentiality, adducts were synthetized by the reaction of 1,2-NphQ with 2'-deoxyguanosine (2'-dG) in N,N-dimethylformamide (DMF), water and calf thymus DNA. 2'-dG adducts were analyzed by 32P post-labelling, HPLC with ultra-violet detection and ultra-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). We found stable DNA adducts detected in DNA. We proposed a formation mechanism by a 1,4-Michael addition with 2'-dG. Adducts with 2'-deoxyxanthosine are formed after a spontaneous deamination of 2'-dG. These adducts are good candidates as biomarkers allowing evaluation of exposure to naphthalene and its derivatives in the development of pathologies such as cancer.


Assuntos
Adutos de DNA , Naftoquinonas , Cromatografia Líquida de Alta Pressão , Naftalenos , Espectrometria de Massas em Tandem
11.
Zhonghua Nan Ke Xue ; 26(7): 611-615, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-33377716

RESUMO

Objective: To observe the clinical effect of priligy (dapoxetine hydrochloride) combined with behavioral therapy and psychological counseling in the treatment of primary premature ejaculation (PPE). METHODS: A total of 202 PPE patients diagnosed from 2017 to 2018 were randomized into a control (n = 100) and an experimental group (n = 102), the former treated with oral priligy at 30 mg 1-3 hours before anticipated sexual activity, and the latter by the same medication combined with 30-minute behavioral therapy and psychological counseling once a month for two times. The therapeutic effects were evaluated according to the Premature Ejaculation Profile (PEP) scores of the patients at 1 and 2 months of treatment. RESULTS: After 1 month of treatment, both groups of the patients showed significant improvement, as compared with the baseline, in the PEP scores on personal distress related to ejaculation (P < 0 05), interpersonal difficulty related to ejaculation (P < 0.05) and satisfaction with sexual intercourse (P < 0.05) but not on perceived control over ejaculation (P > 0.05). At 2 months, however, the patients' scores on all the four PEP items were dramatically improved, even more significantly in the experimental than in the control group, as on perceived control over ejaculation (2.73 ± 0.95 vs 2.22 ± 0.68, P < 0.05), personal distress related to ejaculation (2.97 ± 1.07 vs 2.57 ± 0.69, P < 0.05), interpersonal difficulty related to ejaculation (3.19 ± 1.03 vs 2.77 ± 0.69, P < 0 05) and satisfaction with sexual intercourse (2.85 ± 0.99 vs 2.35 ± 0.63, P < 0.05). There was no statistically significant difference in the incidence rate of adverse events between the experimental and control groups (21.6% vs 20.0%, P > 0.05), and all the symptoms were relieved within 24 hours. CONCLUSIONS: Priligy combined with behavioral therapy and psychological counseling is more effective than priligy alone in improving the sexual function of PPE patients, raise their interest in sexual life and increase the intimacy between the partners, and can even achieve clinical cure in some patients.


Assuntos
Benzilaminas/uso terapêutico , Terapia Cognitivo-Comportamental , Naftalenos/uso terapêutico , Ejaculação Precoce , Psicoterapia , Inibidores de Captação de Serotonina/uso terapêutico , Humanos , Masculino , Ejaculação Precoce/terapia , Resultado do Tratamento
12.
Medicine (Baltimore) ; 99(46): e22566, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33181644

RESUMO

BACKGROUND: Secondary hyperparathyroidism (SHPT) have been associated with poor health outcomes in hemodialysis patients. The cinacalcet has popularized in clinic which has efficacy but more adverse events; the novel oral calcimimetic agents evocalcet has appeared in recent years. However, it is currently unknown whether evocalcet produces more beneficial effects and fewer adverse events in patients with SHPT. The aim of this systematic review is to estimate the safety and efficacy of evocacelt. METHODS: Only randomized controlled trials (RCT) will be included in MEDLINE, EMBASE, the Cochrane Register of Controlled Trials, and PUBMED from July 2010 to July 2020. Two reviewers will screen, select studies, extract data, and assess quality independently. The methodological quality including the risk of bias of the included studies will be evaluated using a modified assessment form, which is based on Cochrane assessment tool. Review Manager 5.3 software will be used for heterogeneity assessment, generating funnel-plots, data synthesis, subgroup analysis, and sensitivity analysis. We will use GRADE system to evaluate the quality of our evidence. RESULTS: We will provide some more practical and targeted results investigating the effect and safety of evocalcet for SHPT on hemodialysis in the current meta-analysis. CONCLUSION: The stronger evidence about evocalcet effect and safety will be provided for clinicians and policymakers. ETHICS AND DISSEMINATION: Ethical approval will be unnecessary because the data being included in this systematic review come from published literature and there will be no concerns regarding privacy. Findings of this research will be disseminated in a peer-reviewed journal or conference presentations. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/N59RB.


Assuntos
Hiperparatireoidismo Secundário/tratamento farmacológico , Naftalenos/normas , Pirrolidinas/normas , Diálise Renal/métodos , Calcimiméticos/normas , Calcimiméticos/uso terapêutico , Protocolos Clínicos , Humanos , Metanálise como Assunto , Naftalenos/uso terapêutico , Pirrolidinas/uso terapêutico , Diálise Renal/tendências , Insuficiência Renal Crônica , Revisões Sistemáticas como Assunto
13.
Huan Jing Ke Xue ; 41(11): 5133-5142, 2020 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124257

RESUMO

There are many sites contaminated by polycyclic aromatic hydrocarbons (PAHs) or combined PAHs-heavy metal in China, which pose serious health-risks to local people and environments. Dissipative quartz crystal microbalance (QCM-D) was applied to investigate the adsorption of naphthalene to two organic-modified smectite clays (cetyltrimethyl ammonium bromide modified montmorillonite, CTAB-SMF, and 3-mercapto propyl trimethoxy silane modified montmorillonite, TMSP-SMF) and original SMF, together with batch adsorption experiments. The results, based on in-situ online QCM-D experiments, showed that the adsorption sites of CTAB-SMF on naphthalene were mainly CTAB grouped between the interlayers of clay particles, while TMSP-SMF's were TMSP grouped on the surfaces of clay particles. The isotherms of naphthalene adsorption to CTAB-SMF fitted well (R2>0.92) with the Freundlich model, while the adsorption isotherms to TMSP-SMF and SMF fitted well with the Langmuir model (R2>0.96). The parameters of CTAB-SMF (n>1) indicated that the adsorption sites of naphthalene to CTAB-SMF were heterogeneous and the adsorption increases at higher equilibrium concentration. The adsorption capacity qmax of TMSP-SMF is significantly greater than that of SMF (P<0.05). Based on the calculation, the value of ΔHobs for these three clays (CTAB-SMF, TMSP-SMF, and SMF) were within the range of -30 to -10 kJ·mol-1, which indicated that it was a spontaneous exothermic physical process. The solution ionic strength could decrease the adsorption of naphthalene to SMF, but had limited effects on naphthalene adsorption to the two organo-modified clay particles. The existence of Cu2+ in the solution could enhance naphthalene adsorption to the three particles, and naphthalene could improve Cu2+ adsorption to these two modified clays. The results of this study show that QCM-D is a useful technique to indicate the changes of clay film during the process of adsorption, and the two organo-modified clay particles have the potential to be remediation materials to remediate PAHs or PAHs-heavy metal-contaminated sites.


Assuntos
Bentonita , Hidrocarbonetos Policíclicos Aromáticos , Adsorção , China , Humanos , Naftalenos
14.
Huan Jing Ke Xue ; 41(9): 4133-4140, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124295

RESUMO

Naphthalene sulfonic acid is widely used in the industry. In this study, H acid (1-amino-8-naphthol-3,6-disulfonic acid) was selected as the characteristic pollutant, and the alkali-activated, thermally-activated, and alkali-heat-complex activated persulfate (PS) degradation of H acid was analyzed. The effects of other factors on complex activation were discussed. The experimental results showed that with the addition of calcium oxide from 0 to 1250 mg ·L-1, the H acid removal rate increased from 42.5% to 82.8% after 100 min of reaction. The removal rate of H acid in thermal activation is positively correlated with temperature. The removal rate of H acid at 65℃ is 77.5%, and the apparent activation energy is 37.85 kJ ·mol-1. Although composite activation speeds up the reaction rate, rapid degradation of PS at high temperatures caused the degradation of H acid to be worse than single thermal activation. The change in PS concentration did not significantly improve the removal rate of H acid, and the inorganic anion CO32- was not conducive to the removal of H acid. Compound activation is not ideal for the mineralization of H acid, and the removal rate of TOC is only 16%. GC-MS identified the degradation product of H acid as terephthalic acid, indicating that phthalic anhydride may be formed after the naphthalene ring is opened.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Naftalenos , Oxirredução , Sulfatos
15.
Proc Natl Acad Sci U S A ; 117(41): 25386-25395, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32989125

RESUMO

Exposure to air pollution causes adverse health outcomes, but the toxicity mechanisms remain unclear. Here, we investigated the dynamic toxicities of naphthalene-derived secondary organic aerosol (NSOA) in a human bronchial epithelial cell line (BEAS-2B) and identified the chemical components responsible for toxicities. The chemical composition of NSOA was found to vary with six simulated atmospheric aging conditions (C1-C6), as characterized by high-resolution mass spectrometry and ion mobility mass spectrometry. Global proteome profiling reveals dynamic evolution in toxicity: Stronger proteome-wide impacts were detected in fresh NSOA, but the effects declined along with atmospheric aging. While Nrf2-regulated proteins (e.g., NQO1) were significantly up-regulated, the majority (78 to 97%) of proteins from inflammation and other pathways were down-regulated by NSOA exposure (e.g., Rho GTPases). This pattern is distinct from the reactive oxygen species (ROS)-mediated toxicity pathway, and an alternative cysteine reaction pathway was revealed by the decreased abundance of proteins (e.g., MT1X) prone to posttranslational thiol modification. This pathway was further validated by observing decreased Nrf2 response in reporter cells, after preincubating NSOA with cysteine. Ethynyl-naphthalene probe was employed to confirm the alkylation of cellular proteome thiols on the proteome-wide level by fresh NSOA via in-gel fluorescence imaging. Nontarget analysis identified several unsaturated carbonyls, including naphthoquinones and hydroxylated naphthoquinones, as the toxic components responsible for cysteine reactivity. Our study provides insights into the dynamic toxicities of NSOA during atmospheric aging and identifies short-lived unsaturated carbonyls as the predominant toxic components at the posttranslational level.


Assuntos
Aerossóis/toxicidade , Naftalenos/química , Naftalenos/toxicidade , Proteoma/efeitos dos fármacos , Linhagem Celular , Regulação para Baixo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Estrutura Molecular , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Processamento de Proteína Pós-Traducional , Proteômica , Regulação para Cima
16.
Life Sci ; 259: 118375, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32891612

RESUMO

OBJECTIVE: Short-chain fatty acids were reported to be the precursors of milk fat and can stimulate the de novo synthesis of fatty acids in bovine mammary epithelial cells (bMECs). However, the mechanism has not been elucidated. The purpose of this study was to investigate the effects of sodium butyrate (NaB) on milk fat synthesis in bMECs and explore its potential mechanism. METHODS: Bovine mammary epithelial cells (bMECs) were isolated for subsequent experimental uses. BODIPY staining and triglyceride kit were used to detect the milk fat synthesis in bMECs. Western blotting and RT-PCR assays were performed to detect the expression of related genes in bMECs. Immunoprecipitation was used to detect the acetylation of SREBP1 in bMECs. RESULTS: The results showed that NaB significantly promoted milk fat synthesis, promoted the activity of mechanistic target of rapamycin (mTOR) and S6 kinase (S6K), inhibited the activity of AMP-activated protein kinase (AMPK), and promoted the gene expression of G protein-coupled receptor 41 (GPR41). Knockdown of GPR41 and sterol regulatory element binding protein 1 (SREBP1) and overexpression of sirtuin1 (SIRT1), mTOR inhibitor (rapamycin), and AMPK activator (AICIR) eliminated these effects. These results indicated that NaB increased the nuclear translocation of SREBP1 via the GPR41/AMPK/mTOR/S6K signalling pathway, promoted the acetylation of mature SREBP1a via GPR41/AMPK/SIRT1, and then promoted milk fat synthesis. CONCLUSION: Taken together, these results demonstrated that NaB increased nuclear translocation and acetylation of SREBP1 to promote milk fat synthesis by activating GPR41 and its downstream signalling pathways.


Assuntos
Ácido Butírico/farmacologia , Glicolipídeos/biossíntese , Glicoproteínas/biossíntese , Glândulas Mamárias Animais/efeitos dos fármacos , Receptores Acoplados a Proteínas-G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Carbazóis , Bovinos , Células Cultivadas , Feminino , Imunoprecipitação , Gotículas Lipídicas , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Naftalenos , Reação em Cadeia da Polimerase em Tempo Real , Sirtuína 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
17.
Gene ; 759: 145001, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32738420

RESUMO

BACKROUND: CSCs having the common features of high telomerase activity and high migration and invasion capabilities play a vital role as the initiators of metastasis. Small molecule BIBR1532 has been shown to target cancer cells by inhibiting telomerase. Recent studies have suggested that telomerase activity is associated with epithelial mesenchymal transition (EMT). EMT program, which causes epithelial cells to acquire a mesenchymal morphology, is known to play a significant role in cancer metastasis. METHODS: The hypothesis of our study was that suppression of telomerase in breast cancer and cancer stem cells would interrupt EMT mechanism. Cytotoxicity of BIBR1532 was evaluated using WST-1 assay in all cell lines and the effects of BIBR1532 on apoptosis were investigated with Annexin V. Migration rate of the cells was examined by wound healing assay and sphere forming capacities were observed by hanging drop test. Finally, the expression of 84 EMT-related genes was analyzed by real-time qPCR. RESULTS: The IC50 values for the MDA-MB-231 and breast epithelial stem cells of BIBR1532 were analyzed as 18.04 and 38.71 µl at 72 h, respectively. Interestingly, apoptosis was only induced in stem cells. In hanging drop test, sphere areas were reduced in stem cells treated with BIBR1532. In wound healing assay, BIBR1532 decreased the migration rate of stem cells. Together with this, expression of EMT-related genes were regulated in stem cells towards a epithelial phenotype. CONCLUSION: Our obtained results indicated that telomerase inhibition affects the EMT mechanism. The targeted elimination of breast cancer stem cells by a telomerase inhibitor in cancer treatment may limit the mobility and stemness of cancer cells interrupting the EMT mechanism, thus may prevent metastasis.


Assuntos
Aminobenzoatos/farmacologia , Neoplasias da Mama/metabolismo , Inibidores Enzimáticos/farmacologia , Transição Epitelial-Mesenquimal , Naftalenos/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Movimento Celular , Proliferação de Células , Feminino , Humanos , Células MCF-7 , Células-Tronco Neoplásicas/fisiologia , Telomerase/antagonistas & inibidores
18.
Medicine (Baltimore) ; 99(34): e21866, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846840

RESUMO

INTRODUCTION: Premature ejaculation (PE) affects 8% to 30% of adult men worldwide. Recently, the incidence of PE is on the rise. A series of prior studies suggested that the incidence of PE is related to various biological factors as low testosterone, low serum vitamin D, diabetes, lower urinary tract symptoms, and other psychological factors. At present, the major treatments include selective serotonin reuptake inhibitors antidepressants (dapoxetine, paroxetine), topical anesthetics, phosphodiesterase-5 inhibitor, circumcision, and selective dorsal neurotomy (SDN). The previous study found that SDN is effective for PE. METHODS AND ANALYSIS: The electronic databases of MEDLINE, PubMed, Web of Science, EMBASE, Cochrane Library, Clinicaltrials. org, China National Knowledge Infrastructure Database (CNKI), Wan fang Database, China Biology Medicine Database (CBM), VIP Science Technology Periodical Database, Chinese Clinical Trial Registry will be retrieved. All the randomized controlled trials of selective dorsal penile neurotomy for patients with PE will be included. The outcome includes intravaginal ejaculation latency time and Chinese Index of Sexual Function for Premature Ejaculation-5. We will conduct this study strictly according to the Cochrane Handbook for Systematic Reviews of Interventions. RESULTS: The present study is a protocol for systematic review and meta-analysis without results, and data analysis will be carried out after the protocol. We will share our findings on June 30th of 2021. CONCLUSION: SDN can effectively prolong IELT, but its efficacy has not been assessed scientifically and systematically. To address this limitation, this study will inspect the efficacy and safety of the SDN treatment in patients with PE. ETHICS AND DISSEMINATION: Formal ethical approval is not required in this protocol. We will collect and analyze data based on published studies, and since there are no patients involved in this study, individual privacy will not be under concerns. The results of this review will be disseminated to peer-reviewed journals or submit to related conferences. PROTOCOL REGISTRATION NUMBER: INPLASY202070084.


Assuntos
Pênis/inervação , Ejaculação Precoce/terapia , Nervo Pudendo/cirurgia , Adulto , Anestésicos Locais/uso terapêutico , Benzilaminas/uso terapêutico , Circuncisão Masculina/métodos , Ejaculação/fisiologia , Humanos , Incidência , Masculino , Naftalenos/uso terapêutico , Paroxetina/uso terapêutico , Pênis/fisiopatologia , Inibidores da Fosfodiesterase 5/uso terapêutico , Ejaculação Precoce/epidemiologia , Ejaculação Precoce/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores de Captação de Serotonina/uso terapêutico
19.
Artigo em Inglês | MEDLINE | ID: mdl-32824583

RESUMO

The paper presents the results of laboratory tests on possibilities to utilize active carbons produced in Poland (AG-5 and DTO) and clinoptilolite for removing naphthalene from a water solution in the adsorption process. The concentration of naphthalene in the model solution was 20 mg/dm3. The effects of pH, dose and adsorption time were determined under static conditions. Adsorption kinetics were consistent with the pseudo-second-order model (PSO). Among the applied models, the best fit was obtained using the Langmuir isotherms. The maximum adsorption capacity for the activated carbons (AG-5 and DTO) equaled 24.57 and 30.28 mg/g, respectively. For clinoptilolite, all the analyzed models of adsorption poorly described the adsorption process. The flow conditions were realized by filtration method. On the basis of the obtained results, the breakthrough curves, so-called isoplanes, were prepared and served in turn to determine the adsorption capacities in flow conditions. The total adsorption capacities determined under dynamic conditions of the AG-5 and DTO activated carbons were 85.63 and 94.54 mg/g, respectively, and only 2.72 mg/g for clinoptilolite. The exit curves (isoplanes) were also utilized to determine the mass penetration zone (the adsorption front height), as well as to calculate the rate of mass-exchange zone advance.


Assuntos
Naftalenos , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Polônia , Soluções , Água , Purificação da Água
20.
J Chromatogr A ; 1628: 461486, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822970

RESUMO

In this work, an inexpensive, fast, and selective ionic liquid modified graphene oxide (GO-IL) was synthesized and electrochemically deposited on the inner surface of a stainless-steel tube. Then, it was applied for circulated headspace in-tube solid-phase microextraction (CHS-IT-SPME) of naphthalene from honey samples. Next, the coated tube was replaced with the sample loop of a six-port injection valve for on-line desorption and further HPLC-UV analysis of naphthalene. The sorbent was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (EDX). Different parameters affecting the procedure efficiency, including extraction temperature, extraction time, salt concentration, and sample volume were optimized by central composite design and response surface methodology. Under the optimum conditions, the calibration curve was linear within the range of 0.3-200 ng mL-1, with a regression coefficient of 0.9972. The limits of detection (LOD) and quantification (LOQ) were found to be 0.1 ng mL-1 and 0.3 ng mL-1, respectively. Intra-day and inter-day RSDs% for three replicate measurements of naphthalene at the concentration of 10 ng mL-1 were obtained 3.9% and 5.0%, respectively. Also, good tube-to-tube reproducibility of 5.3% was achieved. Finally, the method was successfully applied for measuring trace amounts of naphthalene in honey samples. Relative recoveries were calculated within the range of 90.0-106.5%, indicating excellent efficiency of the proposed method.


Assuntos
Cromatografia Líquida/métodos , Galvanoplastia/métodos , Grafite/química , Mel/análise , Líquidos Iônicos/química , Naftalenos/isolamento & purificação , Sistemas On-Line , Microextração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Reprodutibilidade dos Testes
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