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1.
Molecules ; 29(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38998991

RESUMO

Weeds are a serious threat to crop production, and the utilization of secondary metabolites of phytopathogenic fungi is considered to be an effective method of weed control. In this study, eight compounds were isolated and purified from the mycelium and fermentation broth extracts of Bipolaris cookei SYBL03. The compounds (1-8), except 2 and 6, are reported for the first time from this genus. The herbicidal activities of compounds 1-8 were studied by evaluating their effects on the seed germination and seedling growth of monocotyledonous and dicotyledonous weeds. The results indicated that compound 7 (Cyclo-N-methylphenylalanyltryptophenyl, cNMPT) exhibited a concentration-dependent dual effect on the growth of weed seedlings and selective herbicidal activity against dicotyledonous weeds. We further investigated the morphological and physiological responses of roots of Amaranthus retroflexus, a dicotyledonous weed, to compound 7. Some changes were found in seedlings grown in 400 µg/mL compound 7 solution for 96 h, such as shortening and swelling of elongation zone cells, reduced number and length of root hairs, damage and wrinkling of the root surface, occurrence of electrolyte leakage, and an increase in ethylene content. These results suggest that compound 7 may exert herbicidal activity by causing stress to weed seedlings. Increased ethylene production could be involved in the response of plants to compound 7.


Assuntos
Bipolaris , Herbicidas , Plantas Daninhas , Plântula , Herbicidas/farmacologia , Herbicidas/química , Herbicidas/isolamento & purificação , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Bipolaris/efeitos dos fármacos , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Amaranthus/efeitos dos fármacos , Amaranthus/crescimento & desenvolvimento , Raízes de Plantas , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento
2.
Anal Biochem ; 676: 115233, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37433362

RESUMO

Exosomes derived from lung cancer typically contain the genetic information of the donor cells. Therefore, exosomes contribute to early diagnosis, treatment effectiveness evaluation, and prognosis assessment of cancer. Based on the biotin-streptavidin system and MXenes nanomaterial, a dual-effect amplification method had been developed to construct an ultrasensitive colorimetric aptasensor for detecting exosomes. MXenes can enhance the loading of aptamer and biotin as the high specific surface area. Biotin-streptavidin system can increase the amount of horseradish peroxidase-linked (HRP-linked) streptavidin, considerably boosting the color signal of the aptasensor. The proposed colorimetric aptasensor exhibited excellent sensitivity, with a detection limit of 42 particles µL-1 and a linear range of 102 to 107 particles µL-1. The constructed aptasensor showed satisfactory reproducibility, stability, and selectivity, confirming the promising application of exosomes in clinical cancer detection.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Exossomos , Estreptavidina , Biotina , Reprodutibilidade dos Testes , Técnicas Biossensoriais/métodos , Limite de Detecção
3.
J Environ Sci (China) ; 125: 388-400, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375924

RESUMO

Removing large concentrations of organic pollutants from water efficiently and quickly under visible light is essential to developing photocatalytic technology and improving solar energy efficiency. This study used a simple hydrothermal method to prepare a non-metallic, S-doped NaTaO3 (S-NTO) photocatalyst, which was then loaded onto biochar (BC) to form a S-NTO/BC composite photocatalyst. After uniform loading onto BC, the S-NTO particles transformed from cubic to spherical. The photogenerated electron-hole pair recombination probability of the composite photocatalyst was significantly lower than those of the NTO particles. The light absorption range of the catalyst was effectively widened from 310 nm UV region to visible region. In addition, a dual-effect catalytic system was constructed by introducing peroxymonosulfate (PMS) into the environment of the pollution to be degraded. The Rhodamine B, Methyl Orange, Acid Orange 7, tetracycline, and ciprofloxacin degradation efficiency at 40 mg/L reached 99.6%, 99.2%, 84.5%, 67.1%, and 70.7%, respectively, after irradiation by a 40 W lamps for 90 min. The high-efficiency visible-light catalytic activity of the dual-effect catalytic system was attributed to doping with non-metallic sulfur and loading of catalysts onto BC. The development of this dual-effect catalytic system provides new ideas for quickly and efficiently solving the problem of high-concentration organic pollution in aqueous environments, rationally and fully utilizing solar energy, and expanding the application of photocatalytic technology to practice.


Assuntos
Poluentes Ambientais , Catálise , Carvão Vegetal , Luz
4.
Pflugers Arch ; 474(3): 303-313, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35084562

RESUMO

Bronchodilator aminophylline may induce atrial or less often ventricular arrhythmias. The mechanism of this proarrhythmic side effect has not been fully explained. Modifications of inward rectifier potassium (Kir) currents including IK1 are known to play an important role in arrhythmogenesis; however, no data on the aminophylline effect on these currents have been published. Hence, we tested the effect of aminophylline (3-100 µM) on IK1 in enzymatically isolated rat ventricular myocytes using the whole-cell patch-clamp technique. A dual steady-state effect of aminophylline was observed; either inhibition or activation was apparent in individual cells during the application of aminophylline at a given concentration. The smaller the magnitude of the control IK1, the more likely the activation of the current by aminophylline and vice versa. The effect was reversible; the relative changes at -50 and -110 mV did not differ. Using IK1 channel population model, the dual effect was explained by the interaction of aminophylline with two different channel populations, the first one being inhibited and the second one being activated. Considering various fractions of these two channel populations in individual cells, varying effects observed in the measured cells could be simulated. We propose that the dual aminophylline effect may be related to the direct and indirect effect of the drug on various Kir2.x subunits forming the homo- and heterotetrameric IK1 channels in a single cell. The observed IK1 changes induced by clinically relevant concentrations of aminophylline might contribute to arrhythmogenesis related to the use of this bronchodilator in clinical medicine.


Assuntos
Canais de Potássio Corretores do Fluxo de Internalização , Aminofilina/efeitos adversos , Animais , Arritmias Cardíacas , Broncodilatadores/efeitos adversos , Miócitos Cardíacos/fisiologia , Potássio/farmacologia , Ratos
5.
Dig Dis Sci ; 67(8): 3993-4007, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34463880

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract. Although many types of drug are used, clinical outcomes are still unsatisfactory. Previous studies have suggested that intestinal bacteria are involved in the pathogenesis of IBD. Accordingly, in an IBD model we evaluated the therapeutic effects of OPS-2071, a low-absorption quinolone antibacterial agent indicated for intestinal infection, and investigated its mechanism of action. METHODS: The therapeutic effects of OPS-2071 and comparison therapies were evaluated using naive CD4 + T cell-transfer IBD model mice. In vitro inhibition of LPS-induced TNF-α production and inhibitory effects on T cell responses stimulated using anti-CD3/CD28 antibody-loaded beads were evaluated using mouse splenocytes and human peripheral blood mononuclear cells. In addition, in vitro activities against bacteria implicated in IBD pathogenesis were tested. RESULTS: OPS-2071 dose-dependently decreased both colonic weight/length ratio and the colitis histological score as compared with the vehicle group. The therapeutic effect of OPS-2071 was equivalent to that of anti-IL-12/23 (p40) antibody. In vitro, OPS-2071 suppressed TNF-α production induced by LPS stimulation and T cell responses in a dose-dependent manner. At high concentrations, these effects were comparable to those of existing immunosuppressive agents, such as prednisolone, in both mouse and human cells. OPS-2071 also showed antibacterial activity against IBD-related bacteria. CONCLUSIONS: Our results suggest that OPS-2071 had both immunosuppressive and antibacterial effects. This dual effect makes OPS-2071 a unique and promising candidate for IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Antibacterianos/uso terapêutico , Colite/induzido quimicamente , Humanos , Imunossupressores/uso terapêutico , Leucócitos Mononucleares , Lipopolissacarídeos/farmacologia , Camundongos , Fator de Necrose Tumoral alfa
6.
J Environ Manage ; 250: 109428, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31545174

RESUMO

The study presents the novel concept of application of fixed bed-batch mode in-situ dual effect of degradation of photo-Fenton and photocatalysis using composite material composed of fuller's earth and foundry sand for the removal of antibiotic Metronidazole. The composite material was involved in the subsequent leaching of iron prompting to in-situ photo-Fenton reactions while TiO2 layer immobilized upon the support involved in photocatalysis. Dual process facilitated the significant reduction in treatment time as 80% of the compound degraded with 30 min of the reaction. Both the processes almost took 180 min for 50% degradation, when applied individually. No doubt, there was an astonishing increase in the rate constant. An artificial neural network model coupled with the genetic algorithm was employed for the optimization of various parameters like H2O2 dose, treatment time, number of beads, pH, etc. Various characterizations have been performed to confirm the novelty of the process. Extended recyclability up to 70 recycles of these composite beads really confirmed the feasibility of this technology for field-scale applications.


Assuntos
Metronidazol , Poluentes Químicos da Água , Algoritmos , Peróxido de Hidrogênio , Ferro , Oxirredução
7.
Pflugers Arch ; 470(2): 315-325, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28948353

RESUMO

Inward rectifier potassium currents (I Kir,x) belong to prominent ionic currents affecting both resting membrane voltage and action potential repolarization in cardiomyocytes. In existing integrative models of electrical activity of cardiac cells, they have been described as single current components. The proposed quantitative model complies with findings indicating that these channels are formed by various homomeric or heteromeric assemblies of channel subunits with specific functional properties. Each I Kir,x may be expressed as a total of independent currents via individual populations of identical channels, i.e., channels formed by the same combination of their subunits. Solution of the model equations simulated well recently observed unique manifestations of dual ethanol effect in rat ventricular and atrial cells. The model reflects reported occurrence of at least two binding sites for ethanol within I Kir,x channels related to slow allosteric conformation changes governing channel conductance and inducing current activation or inhibition. Our new model may considerably improve the existing models of cardiac cells by including the model equations proposed here in the particular case of the voltage-independent drug-channel interaction. Such improved integrative models may provide more precise and, thus, more physiologically relevant results.


Assuntos
Potenciais de Ação , Etanol/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Regulação Alostérica , Animais , Ventrículos do Coração/citologia , Modelos Cardiovasculares , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Canais de Potássio Corretores do Fluxo de Internalização/química , Multimerização Proteica , Ratos , Função Ventricular
8.
Front Immunol ; 15: 1388176, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840908

RESUMO

The tumor microenvironment is closely linked to the initiation, promotion, and progression of solid tumors. Among its constitutions, immunologic cells emerge as critical players, facilitating immune evasion and tumor progression. Apart from their indirect impact on anti-tumor immunity, immunocytes directly influence neoplastic cells, either bolstering or impeding tumor advancement. However, current therapeutic modalities aimed at alleviating immunosuppression from regulatory cells on effector immune cell populations may not consistently yield satisfactory results in various solid tumors, such as breast carcinoma, colorectal cancer, etc. Therefore, this review outlines and summarizes the direct, dualistic effects of immunocytes such as T cells, innate lymphoid cells, B cells, eosinophils, and tumor-associated macrophages on tumor cells within the tumor microenvironment. The review also delves into the underlying mechanisms involved and presents the outcomes of clinical trials based on these direct effects, aiming to propose innovative and efficacious therapeutic strategies for addressing solid tumors.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/patologia , Animais , Imunidade Inata , Comunicação Celular/imunologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Evasão Tumoral , Imunoterapia/métodos
9.
Heliyon ; 10(12): e32894, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38994084

RESUMO

This study investigated the novel application of Fe-TiO2-allophane catalysts with 6.0 % w/w of iron oxide and two TiO2 proportions (10 % and 30 % w/w) for degrading atrazine (ATZ) using the heterogeneous dual-effect (HDE) process under sunlight. Comparative analyses with Fe-allophane and TiO2-allophane catalysts were conducted in both photocatalysis (PC) and HDE processes. FTIR spectra reveal the unique hydrous feldspathoids structure of allophane, showing evidence of new bond formation between Si-O groups of allophane clays and iron hydroxyl species, as well as Si-O-Ti bonds that intensified with higher TiO2 content. The catalysts exhibited an anatase structure. In Fe-TiO2-allophane catalysts, iron oxide was incorporated through the substitution of Ti4+ by Fe3+ in the anatase crystal lattice and precipitation on the surface of allophane clays, forming small iron oxide particles. Allophane clays reduced the agglomeration and particle size of TiO2, resulting in an enhanced specific surface area and pore volume for all catalysts. Iron oxide incorporation decreased the band gap, broadening the photoresponse to visible light. In the PC process, TiO2-allophane achieves 90 % ATZ degradation, attributed to radical species from the UV component of sunlight. In the HDE process, Fe-TiO2-allophane catalysts exhibit synergistic effects, particularly with 30 % w/w TiO2, achieving 100 % ATZ degradation and 85 % COD removal, with shorter reaction time as TiO2 percentage increased. The HDE process was performed under less acidic conditions, achieving complete ATZ degradation after 6 h without iron leaching. Consequently, Fe-TiO2-allophane catalysts are proposed as a promising alternative for degrading emerging pollutants under environmentally friendly conditions.

10.
Front Pharmacol ; 15: 1339146, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38449811

RESUMO

Endoplasmic reticulum (ER) homeostasis is essential for maintaining human health, and once imbalanced, it will trigger endoplasmic reticulum stress (ERS), which participates in the development of digestive system tumors and other diseases. ERS has dual effect on tumor cells, activating adaptive responses to promote survival or inducing apoptotic pathways to accelerate cell death of the tumor. Recent studies have demonstrated that Chinese botanical drug extracts can affect the tumor process of the digestive system by regulating ERS and exert anticancer effects. This article summarizes the dual effect of ERS in the process of digestive system tumors and the intervention of Chinese botanical drug extracts in recent years, as reference for the combined treatment of digestive system tumors with Chinese and modern medicine.

11.
Comput Biol Med ; 152: 106421, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527780

RESUMO

Liver tumours are diseases with high morbidity and high deterioration probabilities, and accurate liver area segmentation from computed tomography (CT) scans is a prerequisite for quick tumour diagnosis. While 2D network segmentation methods can perform segmentation with lower device performance requirements, they often discard the rich 3D spatial information contained in CT scans, limiting their segmentation accuracy. Hence, a deep residual attention-based U-shaped network (DRAUNet) with a biplane joint method for liver segmentation is proposed in this paper, where the biplane joint method introduces coronal CT slices to assist the transverse slices with segmentation, incorporating more 3D spatial information into the segmentation results to improve the segmentation performance of the network. Additionally, a novel deep residual block (DR block) and dual-effect attention module (DAM) are introduced in DRAUNet, where the DR block has deeper layers and two shortcut paths. The DAM efficiently combines the correlations of feature channels and the spatial locations of feature maps. The DRAUNet with the biplane joint method is tested on three datasets, Liver Tumour Segmentation (LiTS), 3D Image Reconstruction for Comparison of Algorithms Database (3DIRCADb), and Segmentation of the Liver Competition 2007 (Sliver07), and it achieves 97.3%, 97.4%, and 96.9% Dice similarity coefficients (DSCs) for liver segmentation, respectively, outperforming most state-of-the-art networks; this strongly demonstrates the segmentation performance of DRAUNet and the ability of the biplane joint method to obtain 3D spatial information from 3D images.


Assuntos
Processamento de Imagem Assistida por Computador , Neoplasias Hepáticas , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Abdome , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
12.
Front Psychol ; 14: 1247133, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868605

RESUMO

Music, an influential environmental factor, significantly shapes cognitive processing and everyday experiences, thus rendering its effects on creativity a dynamic topic within the field of cognitive science. However, debates continue about whether music bolsters, obstructs, or exerts a dual influence on individual creativity. Among the points of contention is the impact of contrasting musical emotions-both positive and negative-on creative tasks. In this study, we focused on traditional Chinese music, drawn from a culture known for its 'preference for sadness,' as our selected emotional stimulus and background music. This choice, underrepresented in previous research, was based on its uniqueness. We examined the effects of differing music genres (including vocal and instrumental), each characterized by a distinct emotional valence (positive or negative), on performance in the Alternative Uses Task (AUT). To conduct this study, we utilized an affective arousal paradigm, with a quiet background serving as a neutral control setting. A total of 114 participants were randomly assigned to three distinct groups after completing a music preference questionnaire: instrumental, vocal, and silent. Our findings showed that when compared to a quiet environment, both instrumental and vocal music as background stimuli significantly affected AUT performance. Notably, music with a negative emotional charge bolstered individual originality in creative performance. These results lend support to the dual role of background music in creativity, with instrumental music appearing to enhance creativity through factors such as emotional arousal, cognitive interference, music preference, and psychological restoration. This study challenges conventional understanding that only positive background music boosts creativity and provides empirical validation for the two-path model (positive and negative) of emotional influence on creativity.

14.
Front Nutr ; 9: 1042590, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532517

RESUMO

Introduction: The extensive occurrence of acrylamide in heat processing foods has continuously raised a potential health risk for the public in the recent 20 years. Machine learning emerging as a robust computational tool has been highlighted for predicting the generation and control of processing contaminants. Methods: We used the least squares support vector regression (LS-SVR) as a machine learning approach to investigate the effects of flavone carbon and oxygen glycosides on acrylamide formation under a low moisture condition. Acrylamide was prepared through oven heating via a potato-based model with equimolar doses of asparagine and reducing sugars. Results: Both inhibition and promotion effects were observed when the addition levels of flavonoids ranged 1-10,000 µmol/L. The formation of acrylamide could be effectively mitigated (37.6%-55.7%) when each kind of flavone carbon or oxygen glycoside (100 µmol/L) was added. The correlations between acrylamide content and trolox-equivalent antioxidant capacity (TEAC) within inhibitory range (R 2 = 0.85) had an advantage over that within promotion range (R 2 = 0.87) through multiple linear regression. Discussion: Taking ΔTEAC as a variable, a LS-SVR model was optimized as a predictive tool to estimate acrylamide content (R 2 inhibition = 0.87 and R 2 promotion = 0.91), which is pertinent for predicting the formation and elimination of acrylamide in the presence of exogenous antioxidants including flavonoids.

15.
ACS Appl Mater Interfaces ; 14(25): 28826-28833, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35713617

RESUMO

Defect accumulation and nonradiative recombination at the interface of the electron-transport layer (ETL) and the photosensitive layer are inevitable obstacles to efficient and stable perovskite solar cells (PSCs). Herein, we reported a dual-effect interface modification strategy that employs potassium tetrafluoroborate (KBF4) molecules for the simultaneous passivation of the SnO2/perovskite interface and perovskite grain boundaries. The introduced highly electronegative BF4- enriched at the SnO2 surface and the chemical bond interaction between them can effectively reduce the hydroxyl (-OH) group defects on the surface of SnO2, improve electron mobility, and reduce nonradiative recombination. Meanwhile, partial K+ diffuses into the grain boundaries, causing the halogen ions to be uniformly distributed in the perovskite film and resulting in better crystallinity. Therefore, the performance of the experimental device was improved from 20.34 to 22.90% compared with the reference device, with a high electrical performance (JSC = 25.1 mA cm-2, VOC = 1.137 V). In particular, the unencapsulated target PSCs retained 85% of their original PCE after aging for 1000 h under ambient conditions (70 ± 10% RH) in the dark.

16.
Environ Sci Pollut Res Int ; 28(34): 47327-47341, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33890217

RESUMO

In the present investigation, a novel Fe-TiO2 composite was fabricated by mixing fly ash (FA), foundry sand (FS), and bentonite clay for the degradation of paracetamol (PCM). This composite acts as a surface for immobilizing the TiO2 catalyst (using the dip-coating method) besides facilitating the leaching of iron (FA and FS) in acidic conditions. Leached iron (in the form of Fe(II), Fe(III), and total iron) promotes the photo-Fenton (with the addition of H2O2 in the system) while the surface-active TiO2 layer leads to photocatalysis, thus leading to in situ dual process combining photocatalysis and photo-Fenton in one system. This dual process led to a synergy of 75% in comparison to the photocatalysis and photo-Fenton process owing to the large production of •OH. Various parameters such as H2O2 dose (525 mg l-1), number of beads (80), degradation time (215 min), and volume (200 ml) were optimized, and 96.6% of reduction in PCM was observed. Durability study of catalyst showed a minor reduction in the activity of the catalyst after 30 cycles. The TiO2 catalyst was still intact as a film, and iron leaching was also occurring from the beads even after recycling, thus confirming their long-term durability in terms of dual effect. The stability and durability of the composite were confirmed by characteristic analysis such as SEM/EDS. Mineralization of PCM was concluded through the estimation of degradation by-products using GC-MS analysis followed by estimation of nitrate and nitrite ions.


Assuntos
Peróxido de Hidrogênio , Preparações Farmacêuticas , Acetaminofen , Catálise , Compostos Férricos , Oxirredução , Titânio
17.
J Clin Med ; 10(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361981

RESUMO

A growing body of studies has recently shown that abused drugs could simultaneously induce the paradoxical effect in reward and aversion to influence drug addiction. However, whether morphine induces reward and aversion, and which neural substrates are involved in morphine's reward and aversion remains unclear. The present study first examined which doses of morphine can simultaneously produce reward in conditioned place preference (CPP) and aversion in conditioned taste aversion (CTA) in rats. Furthermore, the aversive dose of morphine was determined. Moreover, using the aversive dose of 10 mg/kg morphine tested plasma corticosterone (CORT) levels and examined which neural substrates were involved in the aversive morphine-induced CTA on conditioning, extinction, and reinstatement. Further, we analyzed c-Fos and p-ERK expression to demonstrate the paradoxical effect-reward and aversion and nonhomeostasis or disturbance by morphine-induced CTA. The results showed that a dose of more than 20 mg/kg morphine simultaneously induced reward in CPP and aversion in CTA. A dose of 10 mg/kg morphine only induced the aversive CTA, and it produced higher plasma CORT levels in conditioning and reacquisition but not extinction. High plasma CORT secretions by 10 mg/kg morphine-induced CTA most likely resulted from stress-related aversion but were not a rewarding property of morphine. For assessments of c-Fos and p-ERK expression, the cingulate cortex 1 (Cg1), prelimbic cortex (PrL), infralimbic cortex (IL), basolateral amygdala (BLA), nucleus accumbens (NAc), and dentate gyrus (DG) were involved in the morphine-induced CTA, and resulted from the aversive effect of morphine on conditioning and reinstatement. The c-Fos data showed fewer neural substrates (e.g., PrL, IL, and LH) on extinction to be hyperactive. In the context of previous drug addiction data, the evidence suggests that morphine injections may induce hyperactivity in many neural substrates, which mediate reward and/or aversion due to disturbance and nonhomeostasis in the brain. The results support the paradoxical effect hypothesis of abused drugs. Insight from the findings could be used in the clinical treatment of drug addiction.

18.
Water Res ; 194: 116894, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33592355

RESUMO

Phosphorus (P) release from sediment is a key process affecting the effectiveness of eutrophication mitigation. We hypothesized that high nitrate (NO3-) input may have dual effect on sediment P release: reduce the sediment P release by improving the oxidation of sediment or promote P release by stimulating the growth of phytoplankton and increase the decomposition rates and oxygen consumption at the sediment water interface. To test the effect of different NO3- concentrations, we conducted a three-month experiment in 15 cement tanks (1 m3), with five targeted concentrations of NO3-: control, 2 mg L-1, 5 mg L-1, 10 mg L-1, and 15 mg L-1. The results showed that: i) when NO3- was maintained at high levels: NO3-≥5-7 mg L-1 (range of median values), there was no effect of NO3- on net P release from the sediment, likely because the positive effects of NO3- (increasing oxidation) was counteracted by a promotion of phytoplankton growth. ii) after NO3- addition was terminated NO3- dropped sharply to a low level (NO3-≤0.4 mg L-1), followed by a minor P release in the low N treatments but a significant P release in the high N treatments, which likely reflect that the inhibition effect of NO3- on P release decreased, while the promotion effects at high NO3- concentrations continued. The results thus supported our hypotheses of a dual effect on sediment P release and suggest dose-dependent effect of NO3- loading on stimulating P release from the sediment, being clear at high NO3- exceeding 5-7 mg L-1.


Assuntos
Lagos , Poluentes Químicos da Água , China , Eutrofização , Sedimentos Geológicos , Nitratos , Fósforo/análise , Poluentes Químicos da Água/análise
19.
Chemosphere ; 280: 130949, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34162111

RESUMO

Chloride ion (Cl-) is ever-present in aquatic environments. Different Cl- concentration have been reported in industrial water (760 mM), surface water (<21 mM), seawater (540 mM) and groundwater (<21 mM) which could potentially accumulate into large concentrations in the sea. This mini-review examines more than 200 studies and found that Cl- ions can react with strong oxidants (SO4•-, •OH, and HSO5-) generated from persulfate activation, inducing the formation of chlorine radicals, that can either (1) directly react with organics or (2) generate chlorine radicals that can participate in the conversion of the organic substrate. Although the impact of chloride radicals have been identified as either negligible, positive, or negative (inhibitive) at different Cl- concentrations, only a few studies have considered the possible generation of chlorinated by-products. Another essential detail that is often neglected is the mutagenicity and toxicity of these products, as only a few studies have reported on the biotoxicity, AOX (adsorbable organic halogen) and the degree of mineralization of Cl- containing persulfate activated AOPs (Advanced Oxidation Process). Future studies need to consider the chemical analysis of the degradation products as well as the mutagenicity, toxicity and the biological effects pre and post-oxidation process. This evaluation will address several key issues including the properties, occurrence, and toxicity of the chlorinated products, which can significantly benefit its application in a large-scale environmental application.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloretos , Cloro , Halogênios , Oxirredução , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
20.
Environ Sci Pollut Res Int ; 25(19): 18424-18433, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29696539

RESUMO

The effect of biochar, derived from one-step microwave pyrolysis of sewage sludge (OMPSS), on the removal of industrial wastewater (eosin and safranine T) was investigated in this study. Meanwhile, the multiple-reuse potential of biochar as microwave receptor to raise the pyrolysis temperature was also tested during the pyrolysis process. The results showed that OMPSS prepared adsorbents had excellent adsorption performance, achieving the highest removal efficiencies of 97.3 and 95.9% for eosin and safranine T, respectively. Further analysis indicated that this was due to its appropriate porous structure and surface chemistry characteristics, where the SBET and pore volume of adsorbent AC-1 reached 459 m2/g and 0.23 cm3/g, respectively. The multiple reuses of biochar adsorbents after five times as microwave receptor was feasible, where the pyrolysis temperature could increase sharply from room temperature to 800 °C within 5 min. The mechanism analysis revealed that the limiting stage of adsorption was chemical sorption. This research provided an alternative way for the preparation of functional adsorbent and microwave receptor. Graphical abstract ᅟ.


Assuntos
Carvão Vegetal/química , Micro-Ondas , Pirólise , Esgotos/química , Purificação da Água/métodos , Adsorção , Temperatura Alta , Porosidade , Propriedades de Superfície , Águas Residuárias/química , Poluentes Químicos da Água/análise
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