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1.
Cereb Cortex ; 33(6): 2969-2981, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35718539

RESUMO

BACKGROUND: The potential for acute exercise to enhance attention has been discussed in the literature. However, the neural mechanisms by which acute exercise affects attention remain elusive. METHOD: In this study, we first identified an optimized acute Tai Chi Chuan (ATCC) exercise protocol that enhances sustained attention performance and then aimed to determine the neural substrates of exercise-enhanced attention. Reaction time (RT) from the psychomotor vigilance test (PVT) was used to evaluate sustained attention. In Experiment 1, improvements in RTs were compared among six different exercise protocols. In Experiment 2, the participants completed the PVT in an MRI scanner on both rest and exercise days. RESULTS: Experiment 1 showed that practicing TCC 3 times for a total of 20 minutes, followed by 10-minute rest periods, resulted in the largest improvements in RTs. Experiment 2 showed that ATCC enhanced sustained attention, as evidenced by shorter RTs, and resulted in greater cuneus/precuneus activation after exercise than in the rest condition. Exercise-induced changes in brain activities across a distributed network exhibited significant correlations with attention. CONCLUSION: Therefore, this study indicates that ATCC effectively enhances sustained attention and underscores the key role of the cuneus/precuneus and frontoparietal-cerebellar regions in facilitating vigilance among young adults.


Assuntos
Tai Chi Chuan , Humanos , Adulto Jovem , Tai Chi Chuan/métodos , Exercício Físico , Lobo Occipital , Lobo Parietal , Atenção
2.
J Environ Manage ; 312: 114920, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35358845

RESUMO

Endogenous partial denitrification (EPD) and denitrifying phosphorous removal (DPR) were combined in a novel A2/O - MBBR (Anaerobic Anoxic Oxic - Moving Bed Biofilm Reactor) system for low carbon/nitrogen (C/N) ratio wastewater treatment. The DPR performance was compared and the nutrient metabolism was elucidated based on the optimization of hydraulic retention time (HRT, 4-12 h) and nitrate recycling (R, 200%-600%). In the continuous-flow, the nitrate (NO3-) denitrification accompanied by nitrite (NO2-, via EPD) accumulation with the nitrate-to-nitrite transformation ratio (NTR) of 35.87%-43.31% in the anoxic zones. At HRT of 12 h with R of 500%, batch test initially revealed the DPR mechanism using both NO3- and NO2- as electron acceptor, where denitrifying phosphorus accumulation organisms (DPAOs) and denitrifying glycogen accumulation organisms (DGAOs) were the main contributors for EPD with incomplete denitrification (NO3- → NO2-). Furthermore, stoichiometry-based functional bacteria analysis displayed that higher bioactivity of DPAOs (NO2-→N2, 57.30%; NO3-→N2, 35.85%) over DGAOs (NO3-→N2, 6.85%) facilitated the anoxic NO3- reduction. Microbial community analysis suggested that Cluster I of Defluviicoccus-GAO group (∼4%) was responsible for stable NO2- accumulation performance via EPD, while increased Accumulibacter-PAO group (by ∼15%) contributed to the advanced nutrient removal. Based on the achievement of NO2- accumulation, the application feasibility of integrated EPD - DPR - Anammox for deep-level nutrient removal was discussed.


Assuntos
Nitrogênio , Purificação da Água , Biofilmes , Reatores Biológicos , Carbono , Desnitrificação , Nitratos , Nitritos , Dióxido de Nitrogênio , Fósforo , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
3.
J Environ Sci (China) ; 104: 69-83, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33985749

RESUMO

The optimization of volume ratio (VAn/VA/VO) and nitrate recycling ratio (R) in a two-sludge denitrifying phosphorus removal (DPR) process of Anaerobic Anoxic Oxic-Moving Bed Biofilm Reactor (A2/O-MBBR) was investigated. The results showed that prolonged anaerobic retention time (HRTAn: 1.25→3.75 hr) exerted favorable effect on chemical oxygen demand (COD) removal (57.26%→73.54%), poly-ß-hydroxyalkanoates (PHA) synthesis (105.70→138.12 mgCOD/L) and PO43- release (22.3→38.9 mg/L). However, anoxic retention time (HRTA) and R exhibited positive correlation with PHA utilization (43.87%-81.34%) and denitrifying phosphorus removal (DPR) potential (ΔNO3-/ΔPO43-: 0.57-1.34 mg/mg), leading to dramatical TN removal variations from 68.86% to 81.28%. Under the VAn/VA/VO ratio of 2:6:0, sludge loss deteriorated nutrient removals but the sludge bioactivity quickly recovered when the oxic zone was recovered. The sludge characteristic and microstructure gradually transformed under the dissolved oxygen (DO) control (1.0-1.5→1.5-2.0 mg/L), in terms of sludge volume index (SVI: 194→57 mL/gVSS), median-particle-size (D50: 99.6→300.5 µm), extracellular polymeric substances (EPS) (105.62→226.18 mg/g VSS) and proteins/polysaccharides (PN/PS) ratio (1.52→3.46). Fluorescence in situ hybridization (FISH) results showed that phosphorus accumulation organisms (PAOs) (mainly Cluster I of Accumulibacter, contribution ratio: 91.79%-94.10%) dominated the superior DPR performance, while glycogen accumulating organisms (GAOs) (mainly Competibacter, contribution ratio: 82.61%-86.89%) was responsible for deteriorative TN and PO43- removals. The optimal HRTA and R assembled around 5-6.5 hr and 300%-400% based on the PHA utilization and DRP performance, and the oxic zones also contributed to PO43- removal although it showed low dependence on DO concentration and oxic retention time (HRTO).


Assuntos
Fósforo , Esgotos , Biofilmes , Reatores Biológicos , Desnitrificação , Hibridização in Situ Fluorescente , Nitratos , Nitrogênio , Nutrientes , Eliminação de Resíduos Líquidos
4.
J Environ Manage ; 270: 110887, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721325

RESUMO

The long-term effect of nitrate recycling ratios (R = 100%-500%) on the denitrifying phosphorus removal (DPR) characteristics was studied in a novel two-sludge system, which coupled Anaerobic Anoxic Oxic (A2/O) with Moving Bed Biofilm Reactor (MBBR) for simultaneous nitrogen (N) and phosphorus (P) removals. During the 220 days' operation, effluent COD (30.87-45.15 mg/L) can meet the discharge standard completely, but N and P removals were significantly affected by the R-value, including CODintra removal efficiency (CODintra-Re: 56.09-85.98%), TN removal (TN-Re: 52.06-80.50%), anaerobic PO43- release (PO43--An: 10.66-29.02 mg/L) and oxic PO43- absorption (PO43--O: 2.22-6.26 mg/L). Meanwhile, N and P displayed close correlation with the ΔPO43-/ΔNO3- ratio of 4.20-4.41 at R = 300%-400%, resulting in the high-efficient anoxic poly-ß-hydroxyalkanoates (PHA) utilization (ΔPHAA: 64.88 mgCOD/gVSS). Based on the stoichiometry methodology, at R of 300%-400%, the percentages of phosphorus accumulation organisms (PAOs) and glycogen accumulating organisms (GAOs) contributed to ΔPHAAn (ΔGlyAn) were 71.7%, 28.3% (61.3%, 38.7%) in the anaerobic stage, respectively, while N denitrification rate (NDRA: 3.91-3.93 mg N/(gVSS·h)) and P uptake rate (PURA: 3.76-3.90 mg P/(gVSS·h)) reached the peak, suggesting superior DPR performance with higher contribution of denitrifying PAOs (DPAOs) (70%) than denitrifying GAOs (DGAOs) (30%) in the anoxic stage. Microbial community analysis showed that Accumulibacter (27.66-30.01%) was more enriched than Competibacter (13.41-14.34%) and was responsible for the improved C, N, P removals and DPR characteristics. For optimizing operation, the combined effect of nitrate recycling ratio with other process parameters especially economic evaluation should be considered.


Assuntos
Fósforo , Águas Residuárias , Biofilmes , Reatores Biológicos , Desnitrificação , Nitrogênio , Nutrientes , Esgotos , Eliminação de Resíduos Líquidos
5.
J Environ Manage ; 262: 110391, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250835

RESUMO

Granule formation has been recognized as a promising biotechnology in denitrifying phosphorus removal (DPR) systems by facilitating phosphorus accumulation organisms (PAOs) especially denitrifying PAOs (DPAOs), and hydraulic selection made this a more difficult task in continuous operation. This study aimed at exploring the microscopic mechanism and putting forward an effective strategy for DPR granulation under the impact of hydraulic retention time (HRT) (12 h, 10 h, 8 h) in a novel Anaerobic Anoxic Oxic - Moving Bed Biofilm Reactor (A2/O - MBBR) system. With the reduction of intracellular carbon storage (CODintra) efficiency (88.58%-78.53%), nitrogen (N) (85.45%-79.11%) and phosphorus (P) (96.55%-92.47%) removals both dropped, but it exhibited a growth of anoxic phosphorus uptake rate (PURA) (3.79-5.68 mg P/(gMLVSS·h)). The batch tests associating with substrate transformation of poly-ß-hydroxyalkanoates (PHA), glycogen (Gly) agreed well with the corresponding stoichiometry of phosphorus release rate (PRR) (4.83-7.53 mg P/(gMLVSS·h)), PURA (3.55-5.43 mg P/(gMLVSS·h)), oxic phosphorus uptake rate (PURO) (6.08-6.21 mg P/(gMLVSS·h)), and DPAOs/PAOs ratios (57.17%-89.31%), indicating a shift of microbial community. DPR granules gradually stabilized with low sludge volume index (SVI5/SVI30 ratio = 1.1-1.2), dense and compact structure, higher P content (11.63%), more extracted extracellular polymeric substances (EPS) (111.40-160.31 mg/gMLVSS) as proteins/polysaccharides (PN/PS) ratios (1.70-3.47) increased, leading to better sludge settleability and cell hydrophobicity. Fluorescence in situ hybridization (FISH) results showed that PAOs (mainly Cluster I: 20.20%) were the dominant bacteria in the A2/O reactor although a small amount of Defluviicoccus (3.18-3.48%) was responsible for nitrite accumulation, while ammonium-oxidizing bacteria (AOB) (mainly Nitrosomonas: 10.75%) and nitrite-oxidizing bacteria (NOB) (mainly Nitrospira: 15.06%) were enriched in the MBBR.


Assuntos
Fósforo , Esgotos , Biofilmes , Reatores Biológicos , Hibridização in Situ Fluorescente , Nitrogênio , Eliminação de Resíduos Líquidos
6.
Molecules ; 23(6)2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29899218

RESUMO

The overuse of cartap in tea tree leads to hazardous residues threatening human health. A colorimetric determination was established to detect cartap residues in tea beverages by silver nanoparticles (AgNP) sensor with magnetic molecularly imprinted polymeric microspheres (Fe3O4@mSiO2@MIPs) as recognition elements. Using Fe3O4 as supporting core, mesoporous SiO2 as intermediate shell, methylacrylic acid as functional monomer, and cartap as template, Fe3O4@mSiO2@MIPs were prepared to selectively and magnetically separate cartap from tea solution before colorimetric determination by AgNP sensors. The core-shell Fe3O4@mSiO2@MIPs were also characterized by FT-IR, TEM, VSM, and experimental adsorption. The Fe3O4@mSiO2@MIPs could be rapidly separated by an external magnet in 10 s with good reusability (maintained 95.2% through 10 cycles). The adsorption process of cartap on Fe3O4@mSiO2@MIPs conformed to Langmuir adsorption isotherm with maximum adsorption capacity at 0.257 mmol/g and short equilibrium time of 30 min at 298 K. The AgNP colorimetric method semi-quantified cartap ≥5 mg/L by naked eye and quantified cartap 0.1⁻5 mg/L with LOD 0.01 mg/L by UV-vis spectroscopy. The AgNP colorimetric detection after pretreatment with Fe3O4@mSiO2@MIPs could be successfully utilized to recognize and detect cartap residues in tea beverages.


Assuntos
Impressão Molecular/métodos , Prata/química , Chá/química , Tiocarbamatos/análise , Colorimetria , Óxido Ferroso-Férrico/química , Nanopartículas Metálicas , Microesferas , Estrutura Molecular , Dióxido de Silício/química , Tiocarbamatos/efeitos adversos
7.
Neurochem Res ; 41(6): 1323-34, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27053303

RESUMO

In the present study, we investigated the protective mechanism of paeoniflorin (PF), a monoterpene glycoside extracted from Radix Paeoniae alba roots, on MPP(+)-induced neurotoxicity in cultured rat pheochromocytoma cells (PC12). Our work included examination of cell viability assessment, amounts of released lactic dehydrogenase (LDH), intracellular Ca(2+) concentration, cell apoptosis, mitochondrial membrane potential, caspase-3 activity, and expression profiling of two apoptosis-related genes (Bcl-2 and Bax). It was shown that, PF functioned as an MPP(+) antagonist, being able to suppress apoptosis, decrease LDH release and Ca(2+) concentration, attenuate membrane potential collapse and, inhibit caspase-3 activation, decrease in Bax/Bcl-2 ratio. These observations suggest that PF could protect PC12 cells against MPP(+)-induced injury and the mechanism PF's neuroprotective effect was closely associated with Bcl-2 up-regulation and Bax down-regulation. PF has neuroprotective effects on MPP(+)-induced apoptosis in PC12 cells via regulating mitochondrial membrane potential and Bcl-2/Bax/caspase-3 signaling pathways, and this new insight will help develop a PF-based therapeutic strategy for treatmenting neurodegenerative diseases and injury.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Sobrevivência Celular/fisiologia , Glucosídeos/farmacologia , Monoterpenos/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células PC12 , Ratos
8.
Phys Rev E ; 107(2-2): 025103, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36932601

RESUMO

A three-dimensional blunt-base bluff body in a uniform flow is subjected to long-time stochastic dynamics of switching between two opposite wake states. This dynamic is investigated experimentally within the Reynolds number range Re ≃10^{4}-10^{5}. Long-time statistics coupled to a sensitivity analysis to the body attitude (defined as the pitch angle of the body with respect to the incoming flow) show that the wake switching rate decreases as Re increases. Equipping the body with passive roughness elements (turbulators) modifies the boundary layers before separation, seen as the inlet condition for the wake dynamic. Depending on their location and Re, the viscous sublayer length scale and the turbulent layer thickness can be modified independently. This sensitivity analysis to the inlet condition shows that a decrease of the viscous sublayer length scale at a given turbulent layer thickness leads to a decrease in the switching rate, whereas the modification of the turbulent layer thickness has almost no effect on the switching rate.

9.
Sci Total Environ ; 894: 165043, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37355114

RESUMO

Partial denitrification (PD, nitrate (NO3--N) â†’ nitrite (NO2--N)) as a novel pathway for NO2--N production has been widely concerned, but the specific conditions for highly efficient and stable nitrite maintenance are not yet fully understood. In this study, the effects of carbon sources (acetate, R1; propionate, R2; glucose, R3) on NO2--N accumulation was discussed without seeding PD sludge and the mechanism analysis related to sludge characteristic and microbial evolution were elucidated. The optimal NO2--N, nitrate-to-nitrite transformation ratio (NTR) and nitrite removal efficiency (NRE) reached up to 32.10 mg/L, 98.01 %, and 86.95 % in R1. However, due to the complex metabolic pathway of glucose, the peak time of NO2--N production delayed from 30 min to 60 min. The sludge particle size decreased from 154.2 µm (R1), 130.8 µm (R2) to 112.6 µm (R3) with the increasing extracellular polymeric substances (EPS) from 80.75-85.44 mg/gVSS, 82.68-92.75 mg/gVSS to 106.31-110.25 mg/gVSS, where the ratio of proteins/polysaccharides (PN/PS) was proved to be closely associated with NO2--N generation. For the microbial evolution, Saccharimonadales (70.42 %) dominated the glucose system, while Bacillus (7.42-21.63 %) and Terrimonas (4.24-5.71 %) were the main contributors for NO2--N accumulation in the acetate and propionate systems. The achievement of PD showed many advantages of lower carbon demand, minimal sludge production, lesser greenhouse gas emission and prominent nutrient removal, offering an economically and technically attractive alternative for NO3--N containing wastewater treatment.


Assuntos
Nitritos , Esgotos , Nitritos/metabolismo , Nitratos/metabolismo , Águas Residuárias , Desnitrificação , Carbono/metabolismo , Dióxido de Nitrogênio , Propionatos , Reatores Biológicos , Oxirredução , Acetatos , Glucose
10.
Chemosphere ; 297: 134087, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35216986

RESUMO

A three-stage plug flow moving bed biofilm reactor (PF - MBBR, consisting of three identical chambers of N1, N2 and N3) was proposed for nitrifier enrichment using synthetic wastewater. During the stable operation, the average NH4+-N effluent was 0.67 mg/L and NH4+-N removal was as high as 97.19% with the nitrite accumulation ratio (NAR) of 54.23%, although the biofilm thickness and biomass both presented downward trends from N1 (296 µm, 2280 mg/L), N2 (248 µm, 1850 mg/L) to N3 (198 µm, 1545 mg/L). Particularly, the comparative results of three stages revealed that N2 showed the optimum NH4+-N removal (77.27%) and NAR (75.21%) in the continuous-flow, while NAR of N3 unexpectedly maintained a high level of 65.83% in the batch test, suggesting that ammonia oxidizing bacteria (AOB) accounted for absolute advantage over nitrite oxidizing bacteria (NOB). High-throughput sequencing initially verified different distribution of bacterial community structure, where N2 was far away from N1 and N3 with the lowest community richness and community diversity (operational taxonomic units (OTUs): 454(N2)<527(N3)<621(N1)). Proteobacteria (77.60%-83.09%), Bacteroidetes (1.66%-3.66%), Acidobacteria (2.28%-4.67%), and Planctomycetes (1.19%-6.63%) were the major phyla. At the genus level, AOB (mainly Nitrosomonas) accounted for 5.08% (N1), 20.74% (N2) and 14.24% (N3) while NOB (mainly Nitrospira) increased from 0.14% (N1), 7.06% (N2) to 4.91% (N3) with the total percentages of 5.22%, 27.80% and 19.15%. Finally, the application feasibility of MBBR optimization linked with nitrite (NO2--N) accumulation for deep-level nutrient removal was discussed.


Assuntos
Microbiota , Nitritos , Amônia , Bactérias , Biofilmes , Reatores Biológicos/microbiologia , Nitrificação , Nitrogênio , Águas Residuárias
11.
Bioresour Technol ; 361: 127604, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35835421

RESUMO

The combined effects of carbon source (HAc, HPr, Glu, Glu + HAc) and nitrate concentration (40, 80 mg/L labeling as R40, R80) on partial denitrification (PD) were discussed at C/N ratio of 2.5 (COD = 100, 200 mg/L). The optimal NO2--N and NTR reached to 67.03 mg/L, 99.14% in HAc-R80 system, and denitrification kinetics revealed the same conclusion, corresponding to higher COD utilization rate (CUR: 58.46 mgCOD/(gVSS·h)), nitrate reduction rate (NaRR: 29.94 mgN/(gVSS·h)) and nitrite accumulation rate (NiAR: 29.68 mgN/(gVSS·h)). The preference order was HAc > HPr > Glu + HAc > Glu in both R40 and R80 systems due to different metabolic pathways, however, the NO2--N accumulation and kinetic parameters of R80 group were dramatically higher than those in R40 for the same carbon source. The R80 group facilitated more concentrated biodiversity (607-808 OTUs) with Terrimonas and norank_f_Saprospiraceae responsible for high NO2--N accumulation in HAc and HPr served systems, while norank_f_norank_o_Saccharimonadales and OLB13 dominated the Glu containing systems.


Assuntos
Nitratos , Nitritos , Reatores Biológicos , Carbono/metabolismo , Desnitrificação , Cinética , Nitratos/metabolismo , Nitritos/metabolismo , Nitrogênio/metabolismo , Dióxido de Nitrogênio , Óxidos de Nitrogênio , Esgotos
12.
BMC Biotechnol ; 11: 45, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21548923

RESUMO

BACKGROUND: For efficient and large scale production of recombinant proteins in plants transient expression by agroinfection has a number of advantages over stable transformation. Simple manipulation, rapid analysis and high expression efficiency are possible. In pea, Pisum sativum, a Virus Induced Gene Silencing System using the pea early browning virus has been converted into an efficient agroinfection system by converting the two RNA genomes of the virus into binary expression vectors for Agrobacterium transformation. RESULTS: By vacuum infiltration (0.08 Mpa, 1 min) of germinating pea seeds with 2-3 cm roots with Agrobacteria carrying the binary vectors, expression of the gene for Green Fluorescent Protein as marker and the gene for the human acidic fibroblast growth factor (aFGF) was obtained in 80% of the infiltrated developing seedlings. Maximal production of the recombinant proteins was achieved 12-15 days after infiltration. CONCLUSIONS: Compared to the leaf injection method vacuum infiltration of germinated seeds is highly efficient allowing large scale production of plants transiently expressing recombinant proteins. The production cycle of plants for harvesting the recombinant protein was shortened from 30 days for leaf injection to 15 days by applying vacuum infiltration. The synthesized aFGF was purified by heparin-affinity chromatography and its mitogenic activity on NIH 3T3 cells confirmed to be similar to a commercial product.


Assuntos
Fator 1 de Crescimento de Fibroblastos/genética , Pisum sativum/genética , Proteínas Recombinantes/genética , Animais , Fator 1 de Crescimento de Fibroblastos/metabolismo , Inativação Gênica , Proteínas de Fluorescência Verde/genética , Humanos , Camundongos , Células NIH 3T3 , Folhas de Planta/genética , Proteínas Recombinantes/metabolismo , Rhizobium/genética , Sementes/genética
13.
J Ethnopharmacol ; 266: 113451, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33049346

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Alkaloids isolated from Uncaria rhynchophylla (Miq.) Miq. ex Havil. (Rubiaceae), alkaloids (URA) have been used to treat diseases related to the central nervous system, such as Parkinson's disease. Nevertheless, the potential mechanisms underlying their neuroprotective effects are not well-understood. AIM OF THE STUDY: We investigated the neuroprotective effects of URAs in a mouse model of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) and the possible involvement of a molecular signaling pathway. MATERIALS AND METHODS: Two typical experiments for animal behavior despair, the spontaneous motor activity and the rotarod experiments, were employed to evaluate the efficacy of URAs in mice with PD symptoms. Dopamine (DA) neurons and their metabolism were evaluated using high-performance liquid chromatography-tandem mass spectrometry. The mechanism of action of the alkaloids was investigated by analyzing their effects on the phosphoinositide 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway using western blotting. RESULTS: URA treatment effectively improved the behaviors of the mice during the "spontaneous motor activity and latency to fall off the rotarod test". Moreover, URAs demonstrated a protective role in dopaminergic neurons by increasing the expression of the dopamine transporter and tyrosine hydroxylase, which were supposed to be reduced by MPTP, inhibiting dopamine turnover, and changing dopamine and relevant metabolites. In addition to its association with the increase in the Bcl-2/Bad ratio, URA treatment also attenuated the cleaved caspase-3 level and enhanced the phosphorylation of Akt and mTOR. CONCLUSION: These findings provide evidence that URA can effectively protect neurons from the neurotoxicity caused by MPTP in mouse models of PD by up-regulating the PI3K/Akt/mTOR signaling pathway.


Assuntos
Alcaloides/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Fármacos Neuroprotetores/farmacologia , Transtornos Parkinsonianos/tratamento farmacológico , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Alcaloides/isolamento & purificação , Animais , Dopamina/metabolismo , Medicamentos de Ervas Chinesas/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/isolamento & purificação , Transtornos Parkinsonianos/fisiopatologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
14.
J Ethnopharmacol ; 268: 113568, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33188898

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Isolated from Uncaria rhynchophylla (U. rhynchophylla), rhynchophylline (Rhy) has been applied for treating diseases related to central nervous system such as Parkinson's disease. Nevertheless, the molecular mechanism of the neuroprotective effect has not been well interpreted. AIM OF THE STUDY: To investigate the effects of Rhy on MPTP/MPP + -induced neurotoxicity in C57BL/6 mice or PC12 cells and study the mechanisms involved. MATERIALS AND METHODS: The neuroprotective effect of Rhy on MPTP-induced neurotoxicity was evaluated by spontaneous motor activity test, as well as a test of rota-rod on a rat model of Parkinson's disease. The numbers of TH-positive neurons in the substantia nigra pars compacta (SNpc) was assessed by immunohistological. CCK-8, lactate dehydrogenase (LDH), reactive oxygen species (ROS), the concentration of intracellular calcium ([Ca2+]i) and flow cytometry analysis were performed to evaluate the pharmacological property of Rhy on 1-methyl-4-phenylpyridinium (MPP+) induced neurotoxicity in PC12 cells. Besides, LY294002, a PI3K inhibitor was employed to determine the underlying molecular signaling pathway revealing the effect of Rhy by western-blot analysis. RESULTS: The results showed that Rhy exhibited a protective effect against the MPTP-induced decrease in tyrosine hydroxylase (TH)-positive fibers in the substantia nigra at 30 mg/kg, demonstrated by the immunohistological and behavioral outcomes. Furthermore, it has been indicated that cell viability was improved and the MPP+-induced apoptosis was inhibited after the treatment of Rhy at 20 µM, which were severally analyzed by the CCK-8 and the Annexin V/propidium iodide staining method. In addition, Rhy treatment attenuated MPP+-induced up-regulation of LDH, ([Ca2+]i), and the levels of ROS. Besides, it can be revealed from the Western blot assay that LY294002, as a selective Phosphatidylinositol 3-Kinase (PI3K) inhibitor, effectively inhibited the Akt phosphorylation caused by Rhy, which suggested that Rhy showed its protective property through the activated the PI3K/Akt signaling pathway. Moreover, the Rhy-induced decreases of Bax and caspase-3 as the proapoptotic markers and the increase of Bcl-2 as the antiapoptotic marker, were blocked by LY294002 in the MPP+-treated PC12 cells. CONCLUSIONS: Rhy exerts a neuroprotective effect is partly mediated by activating the PI3K/Akt signaling pathway.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Intoxicação por MPTP/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Oxindóis/uso terapêutico , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Herbicidas/toxicidade , Intoxicação por MPTP/induzido quimicamente , Intoxicação por MPTP/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Neurotoxinas/toxicidade , Oxindóis/isolamento & purificação , Oxindóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Uncaria
15.
Bioresour Technol ; 323: 124524, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33421832

RESUMO

Effect of influent COD/NO3- ratios (2.0-5.0) on partial denitrification (PD, NO3- to NO2-) was investigated by seeding denitrifying phosphorus removal (DPR) sludge at ambient temperature (16 ± 2℃). At COD/NO3- ratio of 2.5, the optimal NO2- effluent and nitrate-to-nitrite transformation ratio (NTR) reached up to 27.18 mg/L and 82.18%, respectively, and nitrate removal efficiency (NRE) (59.34 â†’ 97.98%) showed positive relationship with increasing COD/NO3- ratios. The variations were further illustrated by denitrification kinetics, where faster COD degradation (1.55 g COD/(gVSS·d)), more NO3- consumption (0.55 gN/(gVSS·d)) and higher NO2- production (0.52 gN/(gVSS·d)) were observed although the NO2- peaks happened at anoxic 30 min. Microbial analysis showed lower community diversity and more concentrated composition with dominated genera Thauera (14.10%), Terrimonas (9.40%), Saprospiraceae (13.50%) and Flavobacterium (28.23%) at COD/NO3- ratio of 2.5. Based on the achievement of PD, the application feasibility of integrated PD-DPR-Anammox in a two-sludge DPR system for deep-level nutrient removal was discussed.


Assuntos
Nitritos , Esgotos , Reatores Biológicos , Desnitrificação , Nitrogênio , Fósforo , Águas Residuárias
16.
Chemosphere ; 278: 130410, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33819880

RESUMO

Two types of continuous stirred tank moving bed biofilm reactors (ST-MBBR) and plug flow MBBR (PF-MBBR) were compared for nitrification. PF-MBBR showed strong shock resistance to temperature, and ammonium oxidation ratio (AOR) was 9.63% higher than that in the ST-MBBR, although the average biomass and biofilm thickness of ST-MBBR were 7.32-18.59%, 9.44-14.06% higher than those in the PF-MBBR. Meanwhile, a lower nitrite accumulation ratio (NAR) was observed (54.88%) in the PF-MBBR than the ST-MBBR (78.92%) due to different operation modes, and the divergence was demonstrated by the microbial quantitative analysis. Nitrification kinetics revealed that the temperature coefficient (θ) in the ST-MBBR (1.068) was much higher than that in the PF-MBBR (1.006-1.015), proving the contrasting nitrification performances caused by temperature shock. According to the Monod equation, the half-saturation coefficient (KN) in the ST-MBBR was 0.19 mg/L while it varied around 0.12-0.24 mg/L in the PF-MBBR, revealing various NH4+ affinity owing to different biofilm thickness and microbial composition. Finally, MBBR optimization related to operation mode, temperature, and free ammonium (FA) inhibition for nitrite accumulation was discussed.


Assuntos
Nitrificação , Nitritos , Biofilmes , Reatores Biológicos , Cinética
17.
Sci Total Environ ; 744: 140940, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32717471

RESUMO

In a continuous two-sludge denitrifying phosphorus removal (DPR) process of anaerobic anoxic oxic - moving bed biofilm reactor (AAO - MBBR), nitritation was practicable through the combined regulation of high temperature (T: 30-32 °C), short hydraulic retention time (HRT: 8 h) and low dissolved oxygen (DO: 1.0-1.5 mg/L). The system lasted for 90 days with stable nitrite accumulation ratio (NAR > 60%), and the total inorganic nitrogen (TIN) removal was 7% higher than complete nitrification. Ammonia oxidizing bacteria ((AOB) 6.18-9.41%) responsible for nitritation showed a clear relationship with NAR, but Nitrospira (2.11% â†’ 2.35%) gradually outcompeted Nitrobacter (1.19% â†’ 0.31%) under higher temperature. During the transition from nitration to nitritation, the DPR potential (characterized by ΔPO43-/ΔNOx-) increased by 11.90% while the energy requirement of poly-ß-hydroxyalkanoates (PHA) and glycogen (Gly) decreased by 12.58% and 14.50%, respectively, contributing to higher TIN (84.83%) and TP (97.45%) removals. DPR batch tests using different electron acceptors (NO3- .vs. NO3- + NO2-) revealed that removing 1 mg PO43- only consumed 7.12 ± 0.25 mg PHA via NO3- + NO2- (.vs. 8.50 ± 0.12 mg PHA via NO3-) and 16% carbon source was saved although the DPR capability was suppressed as NO2- concentration exceeded 15 mg/L. Based on the achievement of nitritation, the feasibility of integrated DPR - Anammox in the AAO - MBBR system for deep-level nutrient removal was discussed.

18.
Front Plant Sci ; 11: 119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32174932

RESUMO

It is of great importance to combine stress tolerance and plant quality for breeding research. In this study, the role of phytoene desaturase (PDS), ζ-carotene desaturase (ZDS) and carotene isomerase (CRTISO) in the carotenoid biosynthesis are correlated and compared. The three genes were derived from Lycium chinenses and involved in the desaturation of tetraterpene. Their over-expression significantly increased carotenoid accumulation and enhanced photosynthesis and salt tolerance in transgenic tobacco. Up-regulation of almost all the genes involved in the carotenoid biosynthesis pathway and only significant down-regulation of lycopene ε-cyclase (ε-LCY) gene were detected in those transgenic plants. Under salt stress, proline content, and activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) were significantly increased, whereas malonaldehyde (MDA) and hydrogen peroxide (H2O2) accumulated less in the transgenic plants. The genes encoding ascorbate peroxidase (APX), CAT, POD, SOD, and pyrroline-5-carboxylate reductase (P5CR) were shown to responsive up-regulated significantly under the salt stress in the transgenic plants. This study indicated that LcPDS, LcZDS, and LcCRTISO have the potential to improve carotenoid content and salt tolerance in higher plant breeding.

19.
Chemosphere ; 257: 127076, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32485516

RESUMO

The effect of acetate (HAc) and propionate (HPr) on denitrifying phosphorus removal (DPR) was evaluated in a novel two-sludge A2/O - MBBR (anaerobic/anoxic/oxic - moving bed biofilm reactor) system. Results showed that it was the carbon source transformation and utilization especially the composition of poly-ß-hydroxyalkanoates (PHA) (mainly poly-ß-hydroxybutyrate (PHB) and poly-bhydroxyvalerate (PHV)) decided DPR performance, where the co-exist of HAc and HPr promoted the optimal nitrogen (85.77%) and phosphorus (91.37%) removals. It facilitated the balance of PHB and PHV and removing 1 mg NO3- (PO43-) consumed 3.04-4.25 (6.84-9.82) mgPHA, where approximately 40-45% carbon source was saved. Mass balance revealed the main metabolic pathways of carbon (MAn,C (consumed amount in anaerobic stage) and MA-O,C (consumed amount in anoxic and oxic stages): 66.38-76.19%), nitrogen (MDPR,N (consumed amount in DPR): 57.01-65.75%), and phosphorus (MWS,P (discharged amount in waste sludge): 81.05-85.82%). Furthermore, the relative abundance and microbial distribution were assessed to elucidate DPR mechanism (e.g. Accumulibacter, Acinetobacter, Dechloromonas, Competibacter, and Defluviicoccus) in the A2/O reactor and nitrification performance (e.g. Nitrosomonas, Nitrosomonadaceae and Nitrospira) in the MBBR. Carbon source was demonstrated as the key point to stimulate the biodiversity and bioactivity related to DPR potential, and the operational strategy of carbon source addition was proposed based on the utilizing rules of HAc and HPr.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Acetatos , Bactérias/metabolismo , Biofilmes , Reatores Biológicos , Carbono , Desnitrificação , Microbiota , Nitrificação , Nitrogênio/metabolismo , Nutrientes , Fósforo/metabolismo , Propionatos , Esgotos
20.
J Ethnopharmacol ; 245: 112182, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31445131

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The totally-amounted glucosides of paeony (TGP), which are made up of paeoniflorin, albiflorin, oxypaeoniflorin as well as benzoylpaeoniflorin, constitute the Baishao' actively-working component extracted from Radix Paeonia alba employed in conventional oriental medicine aiming to treat cerebrovascular disorders, such as Parkinson's disease. However, its pharmacologic mechanism is not clear. AIM OF THE STUDY: The initial investigation was made on TGP's neuroprotective effects on PD of the mouse model based on 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) as well as the identification of potential involvement of a molecular signaling pathway. MATERIALS AND METHODS: The evaluation of the behavioral damage as well as neurotoxicity in mice was made through MPTP. Spontaneous motor activity test, as well as a test of Rota-rod on mice was employed for the measurement of bradykinesia symptom. Additionally, liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS) works as the determiner of the main monoamine neurotransmitters dopamine (DA) along with its metabolites 3, 4-dihydroxyphenylacetic acid (DOPAC) as well as homovanillic acid (HVA) based on mouse hippocampus connected with the anti-Parkinson's disease like effect of TGP. Besides, the measurement of the effects of TGP treatment on the expressions level of TH, DAT, a-synuclein, p-CREBS133 as well as apoptosis influence was made with the help of western-blot assay with apoptosis-related markers such as Bax and Bcl-2. RESULTS: The results showed that TGP treatment lessened the behavior-based loss shown "in the spontaneous motor activity as well as the potential of falling to rotarod test". In addition, we found that pretreatment with TGP markedly improved motor coordination, striatal dopamine and its metabolite levels. Furthermore, pretreatment of TGP conducted the protection for dopaminergic neurons with the prevented MPTP-induced reductions within the tyrosine hydroxylase (TH), substantia nigra dopaminergic transporter (DAT), as well as increasing α-synuclein protein levels with transformed dopamine catabolism as well as inhibited dopamine turnover. Besides, TGP treatment helped reversed apoptosis signaling molecules Bcl-2/Bax' reduction; meanwhile improving p-CREBS133 the factor of growth signaling in the substantia nigra' decrease. CONCLUSION: These results suggested that TGP can enhance dopaminergic neuron's cell survival in the SNpc in virtue of the activated cAMP/PKA/CREB factor of growth on inhibiting the pathway of second messenger apoptosis as well. In conclusion, the current findings indicate TGP is expected to be a new cure for PD.


Assuntos
Glucosídeos/uso terapêutico , Intoxicação por MPTP/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Paeonia , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dopamina/metabolismo , Glucosídeos/farmacologia , Ácido Homovanílico/metabolismo , Intoxicação por MPTP/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , alfa-Sinucleína/metabolismo
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