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1.
Neuromolecular Med ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31933131

RESUMO

As a type of stress, maternal separation (MS) has been one of the most widely used models in neuropsychiatric research. An increasing number of studies has found that MS not only affects the function of the hypothalamic-pituitary-adrenal axis and hippocampal 5-hydroxytryptamine system, but also causes dysfunction of the central dopamine (DA) system and increases the susceptibility of dopaminergic neurons to pathogenic factors of Parkinson's disease (PD), for instance, 6-hydroxydopamine, thus impairing motor function. We reviewed the impact of MS on the DA system and its correlation with PD and found the following: (1) discrepant effects of MS on the DA system have been reported; (2) MS is a good model to study the impact of stress on the occurrence and development of PD, however, unified modeling criteria of MS are required; (3) correlation between MS and PD may involve the impact of MS on the DA system, which however is not the only connection; (4) intervening measures can block pathways between MS and PD, which provides reference for the prevention of PD in specific populations such as left-behind children.

2.
Water Res ; 172: 115493, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31978838

RESUMO

Bioelectrochemical system (BES) is promising technology to simultaneously treat wastewater and recover energy, and electrode material is important for the system performance. Microbial fuel cell (MFC) is one of typical BES to be applied in wastewater treatment. How to improve the electrode material is significant to improve wastewater treatment, energy recovery and cost effectiveness. In this study, 3D-weaved carbon electrode entity, assembled by multiple pieces of carbon mesh (CM), was proposed to combine all electrode components as entity to facilitate electron conduction and ionic migration, compared with carbon brush (CB) and granular activated carbon (GAC). The result showed that current density and internal resistance of MFC using 3D-weaved CM as horizontally extended inside anode (CM(T)) were 30.9 A m-3 and 4.5 Ω, respectively, with higher output than traditional GAC (22.6 A m-3 and 6.2 Ω). Though GAC had greater electrode filling and surface area for biomass growth, the electron transfer efficiency per unit electrode biomass was only at 0.0019 ± 0.0002 mol g-1 d-1, much lower than CM(T) at 0.0077 ± 0.0009 mol g-1 day-1. Higher ionic migration rate of CM(T) suggested the assisting effect of composite electrode to enhance ionic transportation towards the cathode. Microbial analysis further indicated that 3D-CM electrode network could simultaneously enhance Geobacter abundance and methanogen activity, suggesting the importance of electrode network on electricigens. Furthermore, CM(T) could obtain 10 times higher energy output efficiency than traditional GAC when applied inside anode chamber. This study proved that network construction of anode electrode could promote the electrode performance and cost effectiveness, suggesting the future development of reactor design of bioelectrochemical system.

3.
Environ Technol ; 41(3): 378-388, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30010496

RESUMO

Soil aquifer treatment (SAT), applied after activated sludge treatment (AST), has been widely used for wastewater reclamation. AST and SAT show potential for removing micropollutants, including pharmaceuticals and personal care products (PPCPs). However, the role of sequential combination of AST and SAT on the biodegradation of PPCPs was not clear in previous studies. In this study, the removal characteristics of PPCPs in AST and SAT were evaluated to assess the legitimacy of sequential combination of AST and SAT. SAT showed effective removals of antibiotics (> 80%), including fluoroquinolones and macrolides by sorption, but poor removals of amide pharmaceuticals (i.e. carbamazepine and crotamiton) were observed in both AST and SAT. Additionally, biodegradation contributed to the effective removal of carboxylic PPCPs (i.e. ketoprofen and gemfibrozil) in both ASTs and SAT, but effective biodegradation of halogenated acid and polycyclic aromatic compounds (i.e. clofibric acid and naproxen) was observed only in SAT (82.1% and 81.8%, respectively). Furthermore, the microbial substrate metabolic patterns showed that amino acids, amines, and polymers were biodegradable in SAT, which was fit for the biodegradation characteristics of PPCPs in SAT. For microbial communities, Proteobacteria were dominant in AST and SAT, but Acidobacteria and Actinobacteria were more abundant in SAT than AST, which could contribute to the effective removals of halogenated acid in SAT. Considering PPCP biodegradation and substrate metabolism, SAT displays a wider range on the biodegradation than AST. Therefore, we conclude that these two processes can complement each other when used for controlling PPCPs.


Assuntos
Cosméticos , Água Subterrânea , Preparações Farmacêuticas , Poluentes Químicos da Água , Biodegradação Ambiental , Esgotos , Solo , Eliminação de Resíduos Líquidos
4.
J Hazard Mater ; 386: 121633, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31740301

RESUMO

Impurity Fe could severely damage the performance of resynthesized cathode material, and therefore, LiFePO4 cathode should be removed from the mixed spent LIBs for materials recycling. In this research, a non-hydrometallurgy method has been developed to separate LiFePO4 by selectively peeling-off the LiFePO4 cathode material and the peeling-off process was well explained by theoretical modeling. The peeling-off efficiency of LiFePO4 was approximate 100 % and that of LiMn2O4/LiCoO2/Li(Ni, Co, Al)O2/Li(Ni, Mn, Co)O2 was only 0.08 %. That is, the separating selectivity was 1250. Mechanism study revealed that the peeling-off was achieved through selective destruction of the LiFePO4 crystal and the matrix of polyvinylidene fluoride (PVDF) binder. Particularly, the crystal structure of LiFePO4 was firstly destructed by sulfide, thus LiFePO4 particles were detached from the matrix of PVDF binder. Then, the PVDF binder without LiFePO4 particles filling were more susceptible to be brittlely peeled off by the micro-explosion force of hydrogen from the reaction of Al foil with water due to the weakened mechanical strength. The process is suitable for recycling varied types of spent LIBs, having a strong potential for industrial application.

5.
Asian J Surg ; 43(1): 36-43, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31350089

RESUMO

Laparoscopic splenectomy (LS) is considered as the gold standard in the surgical management of non-traumatic diseases of spleen (NDOS), and robotic splenectomy (RS) is a promising alternative treatment. This study aimed to compare the effectiveness and safety of RS versus LS for NDOS. Several databases were systematically searched for the literature that compared RS with LS for NDOS. Primary outcomes included operative time, blood loss, conversion to open, hospital stay, cost, postoperative complication, and postoperative morbidity. Study-specific effect sizes and their 95% confidence interval (CI) were combined to calculate the pooled value using a fixed-effects or random-effects model. Seven studies were included with 374 patients. Major blood loss (mean difference [MD] = -127.14; 95% CI = -199.87-54.42), conversion to open (rate difference [RD] = -0.06; 95% CI = -0.11-0.01), and postoperative complication (RD = -0.10; 95% CI = -0.20-0.01) were less in the RS group compared with the LS group. There were no differences found in operative time and hospital stay. In our meta-analysis, perioperative mortality was not observed in the RS group. Compared with the LS group, RS group showed comparable effectiveness and safety for the treatment of NDOS based on the current evidence.

6.
J Hazard Mater ; 383: 121153, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31518805

RESUMO

In this study, influences of cations (Na+, K+, Ca2+, and Mg2+), anions (NO3-, Cl-, and SO42-), and humic acid (HA) on the antimicrobial efficacy of silver nanoparticles (AgNPs)/Ag+ against Phanerochaete chrysosporium were investigated by observing cell viability and total Ag uptake. K+ enhanced the antimicrobial toxicity of AgNPs on P. chrysosporium, while divalent cations decreased the toxicity considerably, with preference of Ca2+ over Mg2+. Impact caused by a combination of monovalent and divalent electrolytes was mainly controlled by divalent cations. Compared to AgNPs, however, Ag+ with the same total Ag content exhibited stronger antimicrobial efficacy towards P. chrysosporium, regardless of the type of electrolytes. Furthermore, HA addition induced greater microbial activity under AgNP stress, possibly originating from stronger affinity of AgNPs over Ag+ to organic matters. The obtained results suggested that antimicrobial efficacy of AgNPs was closely related to water chemistry: addition of divalent electrolytes and HA reduced the opportunities directly for AgNP contact and interaction with cells through formation of aggregates, complexes, and surface coatings, leading to significant toxicity reduction; however, in monovalent electrolytes, the dominating mode of action of AgNPs could be toxic effects of the released Ag+ on microorganisms due to nanoparticle dissolution.

9.
Ecotoxicol Environ Saf ; 187: 109820, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31670242

RESUMO

Huge amounts of fly ash (FA) can be annually produced in power plants. Fly ash always contains high levels of arsenic (As) and selenium (Se) due to the preconcentration of these two elements during coal combustion process. It would be much concerned to screen their fractions and potential environmental behaviors in fly ash for beneficial use and treatment. Fast and practical methods for this purpose are urgently needed. Two fast and effective microwave-assisted sequential extraction schemes (MASE) were developed for fast screening As and Se fractions in fly ash for the first time. The extraction parameters including microwave irradiation time, temperature and power energy were optimized by comparing the results from MASE and the conventional scheme (Wenzel method). The results indicate that the extraction efficiency of As and Se in various fractions can be significantly accelerated by microwave irradiation. The whole procedure operation time can be significantly reduced from 24.5 h to 44 min by microwave assistance compared with the conventional shaking schemes. The recoveries of As and Se in the various extracted fractions were all above 80% with relative standard deviations (RSDs) below 8%. The developed methods were further confirmed by the validation of the certified reference material GBW08401 and fly ash samples from six power plants. The developed MASE methods are practical and effective for fast screening arsenic and selenium fractions in fly ash samples.


Assuntos
Arsênico/análise , Cinza de Carvão/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Micro-Ondas , Selênio/análise , Disponibilidade Biológica , Centrais Elétricas
10.
Neuron ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31831331

RESUMO

A balance between synaptic excitation and inhibition (E/I balance) maintained within a narrow window is widely regarded to be crucial for cortical processing. In line with this idea, the E/I balance is reportedly comparable across neighboring neurons, behavioral states, and developmental stages and altered in many neurological disorders. Motivated by these ideas, we examined whether synaptic inhibition changes over the 24-h day to compensate for the well-documented sleep-dependent changes in synaptic excitation. We found that, in pyramidal cells of visual and prefrontal cortices and hippocampal CA1, synaptic inhibition also changes over the 24-h light/dark cycle but, surprisingly, in the opposite direction of synaptic excitation. Inhibition is upregulated in the visual cortex during the light phase in a sleep-dependent manner. In the visual cortex, these changes in the E/I balance occurred in feedback, but not feedforward, circuits. These observations open new and interesting questions on the function and regulation of the E/I balance.

11.
Molecules ; 24(23)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766544

RESUMO

Cancer is one of the foremost causes of death globally and also the major stumbling block of increasing life expectancy. Although the primary treatment of surgical resection, chemotherapy, and radiotherapy have greatly reduced the mortality of cancer, the survival rate is still low because of the metastasis of tumor, a range of adverse drug reactions, and drug resistance. For all this, it is relevant to mention that a growing amount of research has shown the anticarcinogenic effect of phytochemicals which can modulate the molecular pathways and cellular events include apoptosis, cell proliferation, migration, and invasion. However, their pharmacological potential is hindered by their low water solubility, low stability, poor absorption, and rapid metabolism. In this scenario, the development of nanotechnology has created novel formulations to maximize the potential use of phytochemicals in anticancer treatment. Nanocarriers can enhance the solubility and stability of phytochemicals, prolong their half-life in blood and even achieve site-targeting delivery. This review summarizes the advances in utilizing nanoparticles in cancer therapy. In particular, we introduce several applications of nanoparticles combined with apigenin, resveratrol, curcumin, epigallocatechin-3-gallate, 6-gingerol, and quercetin in cancer treatment.

12.
Heliyon ; 5(10): e02556, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31687483

RESUMO

Background and aim: It is commonly noticed that chaotic and inefficient subgenotyping are universally used academically and clinically, a standardized HBV genotype/subgenotype classification criterion is urgently acquired. Sequence similarity, which was commonly used for the last three decades, should be upgraded by phylogenetic analysis in genotyping of recombinant-free HBV strains. Methods: In this study, 4,429 HBV whole-genome sequences were employed to reconstruct the phylogeny of HBV using Bayesian inference. After excluding recombinant sequences, calculating partitioned evolutionary models, excluding recombinant sequences, reconstructing phylogenetic trees, and performing a correlation analysis of genetic distances, geographical distribution and serotypes, we systematically redefined the genotypes and subgenotypes of HBV. Results: Compared to previous taxonomy, fourteen subgenotypes (A5-A7; B5-B9; C2-C4, C7; and D6-D7) were revised in the new standard. Now the HBV is divided into ten genotypes (A-J) and 24 subgenotypes (A1-A3; B1-B5; C1-C6; D1-D6; and F1-F4). Conclusion: Our robust genotype/subgenotype new taxonomy has objectively re-molded the current shape of HBV classification. We believe that all future hepatitis B related researches or diagnosis will be benefited under the new HBV genotyping/subgenotyping standards.

13.
Medicine (Baltimore) ; 98(44): e17381, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689744

RESUMO

BACKGROUND: This study will assess the effectiveness of electroacupuncture (EA) for pain in patients with osteosarcoma post surgery (OSPS). METHODS: In this study, we will comprehensively search the following electronic databases from inception to the present without language restrictions: Cochrane Library, EMBASE, MEDLINE, the Cumulative Index to Nursing and Allied Health Literature, the Allied and Complementary Medicine Database, and Chinese Biomedical Literature Database. Two authors will independently carry out study selection, data extraction, and methodological assessments. RevMan 5.3 software will be used for statistical analysis. RESULTS: The primary outcome is pain intensity. The secondary outcomes consist of event-free survival, overall survival, quality of life, and adverse events. CONCLUSION: The findings of this study will provide helpful evidence of EA treatment for patients with OSPS. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42019146696.


Assuntos
Dor do Câncer/terapia , Eletroacupuntura/métodos , Osteossarcoma/terapia , Intervalo Livre de Doença , Eletroacupuntura/efeitos adversos , Humanos , Osteossarcoma/cirurgia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa
14.
Cell Res ; 29(12): 984-993, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31601978

RESUMO

The phenomenon of plant root tips sensing moisture gradient in soil and growing towards higher water potential is designated as root hydrotropism, which is critical for plants to survive when water is a limited factor. Molecular mechanisms regulating such a fundamental process, however, are largely unknown. Here we report our identification that cytokinins are key signaling molecules directing root growth orientation in a hydrostimulation (moisture gradient) condition. Lower water potential side of the root tip shows more cytokinin response relative to the higher water potential side. Consequently, two cytokinin downstream type-A response regulators, ARR16 and ARR17, were found to be up-regulated at the lower water potential side, causing increased cell division in the meristem zone, which allows the root to bend towards higher water potential side. Genetic analyses indicated that various cytokinin biosynthesis and signaling mutants, including the arr16 arr17 double mutant, are significantly less responsive to hydrostimulation. Consistently, treatments with chemical inhibitors interfering with either cytokinin biosynthesis or cell division completely abolished root hydrotropic response. Asymmetrically induced expression of ARR16 or ARR17 effectively led to root bending in both wild-type and miz1, a previously known hydrotropism-defective mutant. These data demonstrate that asymmetric cytokinin distribution is a primary determinant governing root hydrotropism.

15.
Adv Mater ; 31(46): e1904623, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31588649

RESUMO

Black phosphorus (BP) with unique 2D structure enables the intercalation of foreign elements or molecules, which makes BP directly relevant to high-capacity rechargeable batteries and also opens a promising strategy for tunable electronic transport and superconductivity. However, the underlying intercalation mechanism is not fully understood. Here, a comparative investigation on the electrochemically driven intercalation of lithium and sodium using in situ transmission electron microscopy is presented. Despite the same preferable intercalation channels along [100] (zigzag) direction, distinct anisotropic intercalation behaviors are observed, i.e., Li ions activate lateral intercalation along [010] (armchair) direction to form an overall uniform propagation, whereas Na diffusion is limited in the zigzag channels to cause the columnar intercalation. First-principles calculations indicate that the diffusion of both Li and Na ions along the zigzag direction is energetically favorable, while Li/Na diffusion long the armchair direction encounters an increased energy barrier, but that of Na is significantly larger and insurmountable, which accounts for the orientation-dependent intercalation channels. The evolution of chemical states during phase transformations (from Lix P/Nax P to Li3 P/Na3 P) is identified by analytical electron diffraction and energy-loss spectroscopy. The findings elucidate atomistic Li/Na intercalation mechanisms in BP and show potential implications for other similar 2D materials.

16.
J Environ Manage ; 250: 109399, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31479935

RESUMO

The 350 °C and 700 °C corn straw biochars were used to produce solid fuel briquettes. NovoGro (NG), an industrial by-product, were selected as a binder in the briquetting process. The ratios of the raw material to NG was assumed as 100:1 and 50:1 (denoted as 350NB1, 350NB2, 700NB1 and 700NB2, respectively). The physicochemical and morphological properties, combustion characteristics and gas emissions of the four briquettes were investigated. The results revealed that the biochars and the NG binder performed a good combination. The low temperature biochar briquettes, especially 350NB2, had excellent combustion characteristics, including low H/C and O/C ratios (0.17 and 0.82), low gas emissions (104.06 mg/m3 of CO, 157.25 mg/m3 of NOx and 18.92 mg/m3 of SO2), optimal resistance to mechanical shock (~90%) and high calorific values (21.48 MJ/kg). Thus, NG is a good binder for the briquetting of biochar. The low temperature biochar was a good feedstock for solid fuel production in the improvement of the combustion and emission quality.


Assuntos
Carvão Vegetal , Zea mays , Temperatura Ambiente
19.
J Anesth ; 33(5): 587-593, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31428863

RESUMO

PURPOSE: The aim of this study was to confirm the alleviating effects of the nontourniquet technique on the postoperative acute and chronic pain of patients after total knee arthroplasty (TKA). METHODS: 122 elderly patients undergoing TKA were randomly divided into two groups: group T (n = 58) and group H (n = 64). An electronic inflatable tourniquet was used during TKA in group T. The patients in group H received controlled hypotension but without tourniquet use during the operation. The numeric rating scale (NRS) score was used to evaluate pain level on day 1, day 2, day 3 and day 7 after the operation, and the incidence of chronic pain was judged at 3-month and 1-year follow-ups, and functional recovery of the knee joint was estimated by the active range of knee joint motion (AROM) at the same time points. Cognitive function was assessed by the montreal cognitive assessment scale (MoCA) for 7 days after operation. RESULTS: There were no significant differences in the NRS scores and AROM for 7 days after surgery. The incidence rate of chronic pain in group H (25.0%) was lower than that in group T (41.4%) and the AROM in group H was greater at one year follow-up. The MoCA score in group H was lower than that in group T on day 1 and day 2. CONCLUSION: The nontourniquet combined with controlled hypotension technique can alleviate chronic pain and promote the long-term rehabilitation of patients after TKA.

20.
J Colloid Interface Sci ; 555: 460-469, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400538

RESUMO

In the present study, Ag nanoparticles loaded on polydopamine coated magnetic biochar (MC-PDA-Ag) catalyst was prepared by in-situ reduction approach. The morphology, composition, and structure of MC-PDA-Ag were characterized by the transmission electron microscopy (TEM), the scanning electron microscope (SEM), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometer (VSM). Catalytic reduction tests confirmed that MC-PDA-Ag catalyst showed excellent catalytic performance on the model dyes (MB, RhB, and MO) in the presence of NaBH4. The reduction efficiency of MB exceeded 90% by MC-PDA-Ag even under different initial pH (3-11) and different NaNO3 concentrations (0-0.5 M) within 5 min, indicating that the MC-PDA-Ag catalyst has potential strong universal adaptability in dye wastewater treatment. Furthermore, no significant decrease in catalytic ability was observed after 5 recycles, and the catalyst could be separated by an external magnet, indicating that this as-prepared catalyst exhibited high reusability and easy separability. These results suggest that MC-PDA-Ag composite catalyst can be used as an efficient catalyst for the reduction of organic dyes, and shows great potential application in wastewater treatment.

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