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The phenomenon of nitrogen deposition resulting in species loss in terrestrial ecosystems has been demonstrated in several experiments. Nitrogen (N) and phosphorus (P), as major nutrients required for plant growth, exhibit ecological stoichiometric coupling in many ecosystems. The increased availability of nitrogen can exacerbate the ecological effects of phosphorus. To reveal the ecological effects of phosphorus under nitrogen-limiting and non-limiting conditions, we conducted a controlled N-P interaction experiment over 5 years in the Hulunbuir meadow steppe, where two nitrogen addition levels were implemented: 0 g N·m-2·a-1 (nitrogen-limiting condition) and 10 g N·m-2·a-1 (nitrogen-non-limiting condition), together with six levels of phosphorus addition (0, 2, 4, 6, 8, and 10 g P·m-2·a-1). The results showed that nitrogen addition (under nitrogen-non-limiting conditions) significantly decreased species diversity in the steppe community, which was exacerbated under phosphorus addition. Under nitrogen-limiting conditions, phosphorus addition had no marked impact on species diversity compared to the control; however, there were substantial differences between different levels of phosphorus addition, exhibiting a unimodal change. Under both experimental nitrogen conditions, the addition of 6 g P·m-2·a-1 was the threshold for affecting the community species diversity. Nitrogen addition reduced the relative biomass of legumes, bunch grasses, and forbs, but substantially increased the relative biomass of rhizomatous grasses. In contrast, phosphorus addition only markedly affected the relative biomass of forbs and rhizomatous grasses, with the former showing a unimodal pattern of first increasing and then decreasing with increasing phosphorus addition level, and the latter exhibiting the opposite pattern. The different responses of rhizomatous grasses and other functional groups to nitrogen and phosphorus addition were observed to have a regulatory effect on the changes in grassland community structure. Phosphorus addition may increase the risk of nitrogen deposition-induced species loss. Both nitrogen and phosphorus addition lead to soil acidification and an increase in the dominance of the already-dominant species, and the consequent species loss in the forb functional group represents the main mechanism for the reduction in community species diversity.
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To solve the problems of the lack of property research in organic synthesis experiments and the relative independence of instrumental analytical methods in experiments, we designed a comprehensive undergraduate experiment based on mechanofluorochromic materials. In this project, 4-[bis(4-methylphenyl)amino] benzaldehyde was synthesized via the Vilsmeier-Haack reaction using 4,4'-dimethyltriphenylamine as the raw material. The product was then characterized by mass spectrometry, infrared absorption spectroscopy, and nuclear magnetic resonance spectroscopy. The solvatofluorochromism and mechanofluorochromism of the target material were studied using ultraviolet-visible absorption spectroscopy, fluorescence spectroscopy, etc. Furthermore, the mechanism of mechanofluorochromism was determined using powder X-ray diffraction. Organic synthesis and a series of instrumental analytical methods were combined to form an integrated experiment. The experiment is interesting, scientific, and comprehensive for undergraduates as a creative exercise; moreover, it can inspire their interest in chemical research, cultivate a variety of experimental operation abilities, improve creative-thinking skills, and encourage the development of effective solutions to existing problems in chemical experiments.
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Protein-like substances produced by biochemical reactions after disinfection of Zooplankton like Cyclops and humic substances in natural water are the main components of NOM (Natural organic matter). To eliminate early warning interference in the fluorescence detection of organic matter in natural water, a clustered flower-like AlOOH (aluminum oxide hydroxide) sorbent was prepared. HA (humic acid) and amino acids were selected as mimics of humic substances and protein-like substances in natural water. The results demonstrate that the adsorbent can selectively adsorb HA from the simulated mixed solution and restore the fluorescence properties of tryptophan and tyrosine. Based on these results, a stepwise fluorescence detection strategy was developed and used in natural water rich in zooplanktonic Cyclops. The results show that the established stepwise fluorescence strategy can well overcome the interference caused by fluorescence quenching. The sorbent was also used for water quality control to enhance coagulation treatment. Finally, trial runs of the water plant demonstrated its effectiveness and suggested a potential control method for early warning and monitoring of water quality.
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Contaminantes Químicos del Agua , Purificación del Agua , Minociclina , Fluorescencia , Sustancias Húmicas/análisis , Proteínas , Purificación del Agua/métodos , Contaminantes Químicos del Agua/análisisRESUMEN
OBJECTIVE: To observe the effect of Buyi Pishen acupuncture (acupuncture for invigorating spleen and kidney) on inflammatory factor and synovial cartilage matrix in adjuvant arthritis (AA) rats, and to explore the mechanism of acupuncture for rheumatoid arthritis (RA). METHODS: A total of 60 clean male Wistar rats were randomized into a normal group, a model group, a tripterygium wilfordii polyglycoside tablet (TWP) group and an acupuncture group, 15 rats in each group. Rats in the model group, the TWP group and the acupuncture group received intradermal injection of Freund's complete adjuvant (FCA) at right hind foot pad to induce the AA model. TWP suspension of 8 mg/kg was given by gavage in the TWP group. Acupuncture was applied at "Shenshu" (BL 23), "Pishu" (BL 20) and right "Housanli" (ST 36), "Sanyinjiao" (SP 6), "Yanglingquan" (GB 34) in the acupuncture group, 15 min a time, once a day. The intervention was given 15 days in both TWP group and acupuncture group. The foot-pad swelling degree before modeling, before and after intervention and the arthritis index (AI) score before and after intervention were calculated; the serum levels of interleukin (IL)-1ß, IL-4, IL-10 and tumor necrosis factor-α (TNF-α) were detected by ELISA method; the ultrastructure and histomorphological changes of synovium issue were observed by transmission electron microscope and HE staining; the positive expression of matrix metalloproteinase (MMP)-3 and MMP-9 in synovium issue was detected by immunohistochemistry method. RESULTS: Before intervention, foot-pad swelling degree of the model group, the TWP group and the acupuncture group was increased compared with the normal group (P<0.01). After intervention, foot-pad swelling degree and AI score were increased compared with the normal group (P<0.01), foot-pad swelling degree and AI scores in the TWP group and the acupuncture group were lower than the model group (P<0.05), and those in the acupuncture group were decreased compared with the TWP group (P<0.05). The model group exhibited unclear nuclear membrane of synovial cells, chromatin pyknosis, massive inflammatory cell infiltration and hyperplasia in synovial tissue; the TWP group and the acupuncture group exhibited clear and smooth nuclear membrane of synovial cells, inapparent chromatin pyknosis, less inflammatory cell infiltration and hyperplasia in synovial tissue, the acupuncture group exhibited less matrix destruction as well. Compared with the normal group, serum levels of IL-1ß and TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were increased (P<0.01), while serum levels of IL-4 and IL-10 were decreased (P<0.01) in the model group. Compared with the model group, serum levels of IL-1ß and TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were decreased (P<0.05, P<0.01), while serum levels of IL-4 and IL-10 were increased (P<0.05) in the TWP group and the acupuncture group; compared with the TWP group, serum level of TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were decreased (P<0.05), while serum levels of IL-4 and IL-10 were increased (P<0.05) in the acupuncture group. CONCLUSION: Buyi Pishen acupuncture can effectively improve the injury of articular cartilage in AA rats, its mechanism maybe related to reducing the inflammatory reaction in synovium and inhibiting the degradation of articular cartilage matrix.
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Terapia por Acupuntura , Artritis Experimental , Cartílago Articular , Animales , Artritis Experimental/patología , Artritis Experimental/terapia , Cromatina , Hiperplasia , Interleucina-10 , Interleucina-4 , Masculino , Metaloproteinasa 3 de la Matriz , Metaloproteinasa 9 de la Matriz , Ratas , Ratas Wistar , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
Wearable film-based smart biosensors have been developed for real-time biomolecules detection. Particularly, interfacial co-assembly of reduced graphene oxide-prussian blue (PB-RGO) film through electrostatic interaction has been systematically studied by controllable pH values, achieving optimal PB-RGO nanofilms at oil/water (O/W) phase interface driven by minimization of interfacial free energy for wearable biosensors. As a result, as-prepared wearable biosensors of PB-RGO film could be easily woven into fabrics, exhibiting excellent glucose sensing performance in amperometric detection with a sensitivity of 27.78 µA mM-1 cm-2 and a detection limit of 7.94 µM, as well as impressive mechanical robustness of continuously undergoing thousands of bending or twist. Moreover, integrated wearable smartsensing system could realize remotely real-time detection of biomarkers in actual samples of beverages or human sweat via cellphones. Prospectively, interfacial co-assembly engineering driven by pH-induced electrostatic interaction would provide a simple and efficient approach for acquiring functional graphene composites films, and further fabricate wearable smartsensing devices in health monitoring fields.
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Técnicas Biosensibles , Técnicas Electroquímicas , Ferrocianuros/química , Glucosa/análisis , Grafito/química , Dispositivos Electrónicos Vestibles , Atención a la Salud , Humanos , Tamaño de la Partícula , Propiedades de SuperficieRESUMEN
Molecular dynamics simulation was used to study the adsorption of single wall carbon nanotubes (SCNT) in levofloxacin (LEV) solutions of different concentrations by Radial distribution function, mean square displacement and interaction energy. The results showed that levofloxacin molecules were adsorbed around the carbon nanotubes. The adsorption effect of large concentration solution was not as good as that of low concentration solution because of agglomeration. LEV molecules with different concentration were free diffusion within 15ns, and gradually agglomerated under the influence of adsorption. The energy change is proportional to the concentration of the molecule. The distance between benzene rings corresponding to the agglomeration effect of levofloxacin molecules was 0.4 nm, which should be the effect of parallel-slipped π-π electron-donor-acceptor (EDA) interactions. The simulation results are valuable to study the adsorption and removal of benzenes by adsorbent.
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Nanotubos de Carbono , Adsorción , Difusión , Electrones , Simulación de Dinámica MolecularRESUMEN
The utilization of mechanical energy to control water pollutants under dark conditions is currently a point of study focus. Herein, biochar -zinc oxide (BC-ZnO) composites with various structures were synthesized by co-pyrolysis of cotton and ZnO at different temperature and used for tribo-catalytic reaction. The introduction of BC can improve charge transmission and separation efficiency. Ultraviolet photoelectron spectra (UPS) and density functional theory (DFT) calculation prove the addition of BC can reduce work function of ZnO, and enhance its electron-donating ability. Specially, suitable adsorption amount is the key factor to improve the tribo-catalytic performance. When the pyrolysis temperature is 600 °C, BC-ZnO has the best degradation efficiency, which can degrade 90% Rhodamine B (RhB) in 75 min, while ZnO can degrade only 38%. On this basis, using bovine serum albumin (BSA) as a model, the effect of tribo-catalytic reaction on controlling proteins in water was studied by fluorescence excitation-emission matrix spectroscopy (3D EEM) and infrared microscope, and the transformation of proteins was further analyzed. This study provides a new strategy to improve the tribo-catalytic performance of ZnO, and explores its application prospects of biological wastewater control.
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Contaminantes Químicos del Agua , Óxido de Zinc , Adsorción , Catálisis , Carbón OrgánicoRESUMEN
Patients with epilepsy report that sleep deprivation is a common trigger for breakthrough seizures. The basic mechanism of this phenomenon is unknown. In the Kv1.1-/- mouse model of epilepsy, daily sleep deprivation indeed exacerbated seizures though these effects were lost after the third day. Sleep deprivation also accelerated mortality in ~ 52% of Kv1.1-/- mice, not observed in controls. Voltage-clamp experiments on the day after recovery from sleep deprivation showed reductions in GABAergic tonic inhibition in dentate granule cells in epileptic Kv1.1-/- mice. Our results suggest that sleep deprivation is detrimental to seizures and survival, possibly due to reductions in GABAergic tonic inhibition. ANN NEUROL 2021;90:840-844.
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Epilepsia/fisiopatología , Receptores de GABA-A/metabolismo , Convulsiones/fisiopatología , Privación de Sueño/fisiopatología , Animales , Electroencefalografía/métodos , Ratones , Sueño/fisiologíaRESUMEN
OBJECTIVE: To explore the effect of moxibustion at "Zusanli"(ST36) and "Shenshu"(BL23) on synovitis, and expressions of miR-155, Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), interlukineï¼IL-1ï¼ receptor-associated kinase (IRAK1), tumor necrosis factor receptor-associated factor 6 (TRAF6), nuclear factor κB (NF-κB), IL-1ß, tumor necrosis factor receptor (TNF)-α and IL-6 mRNA and protein of synovial membrane in rheumatoid arthritis (RA) rats, so as to explore its mechanism underlying improvement of RA. METHODS: A total of 48 male Wistar rats were randomly divided into normal control, model, moxibustion and antagonist groups (n=12 rats in each group). The RA model was replicated by placing the rats in a wind, cold and wet environment and injection of Freund's complete adjuvant (CFA, 0.5 mL) into the right hindlimb foot plantar. Moxibustion was applied to bilateral ST36 and BL23 for 30 min, once daily for 21 consecutive days. Rats of the antagonist group was treated by injection of TLR4 antagonist (TAK-242, 1 mg/mL, 0.1 mg/kg) via tail vein, once per day for consecutive 21 d. The joint swelling degree (JSD) and arthritis index (AI, red swelling scale) were determined, and the expression levels of various indicators of miR-155, and TLR4, myeloid MyD88, IRAK1, TRAF6, NF-κB, IL-1ß, TNF-α and IL-6 mRNA and protein were assayed by quantitative real time-PCR and Western blot, separately. RESULTS: Compared with the normal control group, the JSD and AI, and the expression levels of synovial miR-155, TLR4, MyD88, IRAK1, TRAF6, NF-κB, IL-1ß, TNF-α and IL-6 mRNA and protein were significantly increased in the model group (P<0.01). Compared with the model group, the increased levels of JSD and AI, and the expression levels of synovial miR-155, TLR4, MyD88, IRAK1, TRAF6, NF-κB, IL-1ß, TNF-α and IL-6 mRNA and protein were notably down-regulated in both moxibustion and antagonist groups (P<0.01). The effects of moxibustion were evidently superior to the antagonist in down-regulating the abovementioned indexes (P<0.01), except TLR4 mRNA and protein. CONCLUSION: Moxibustion at ST36 and BL23 can reduce the synovitis of RA rats, which is related to its effects in suppressing the expressions of miR-155, TLR4, MyD88, IRAK1, TRAF6, NF-κB, IL-1ß, TNF-α and IL-6 mRNA and protein (i.e., inhibition of miR-155/TLR4/NF-κB signaling).
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Artritis Reumatoide , MicroARNs , Moxibustión , Sinovitis , Animales , Artritis Reumatoide/genética , Artritis Reumatoide/terapia , Masculino , MicroARNs/genética , FN-kappa B/genética , Ratas , Ratas Wistar , Receptor Toll-Like 4/genéticaRESUMEN
The control of interfacial microbial pollution is of great significance for water safety. Herein, the tribo-catalysis ability of zinc oxide (ZnO) has been investigated, which can realize the control of tightly-bound extracellular polymeric substances (T-EPS) in water under dark environment. The DFT calculation proves the Fe doping introduces the impurity level and decreases the work function from 5.071 eV to 5.045 eV, improves the charge separation of ZnO, and eventually enhances the catalytic reaction efficiency. Characterizing the catalytic reaction process by three-dimensional fluorescence (3D EEM) and fluorescence regional integration (FRI) method, it is found that the T-EPS solution can be degraded 75.8% by Fe-ZnO in 12 min, while ZnO can only degrade 32.2%. Combining with high-resolution scanning probe microscope (HR-SPM) and attenuated total reflection method (ATR-FTIR), hydration layers consist with hydroxyl layer (â¼0.23 nm) and water molecular layer (â¼0.27 nm) are observed at the interface between Fe-ZnO and T-EPS solution, and terminal hydroxyl group (OHt) is considered to be the active site for the generation of radicals. This study provides an idea for exploring the mechanism of tribo-catalytic reaction and shows its application prospect in the field of microbial inhibition in water.
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Óxido de Zinc , Catálisis , Matriz Extracelular de Sustancias Poliméricas , AguaRESUMEN
Practical application of metallurgical microbial electrolysis cells (MECs) requires efficient removal of metals and organics in larger reactors. A 40â¯L cylindrical single-chamber MEC fed acetate was used to achieve high removals of W(VI) and Mo(VI). In the presence of both metals, there were nearly complete removals of W (97 â 98%), Mo (98 â 99%), and acetate (95 â 96%), along with a low level of hydrogen production (0.0037-0.0039â¯L/L/d) at a hydraulic residence time (HRT) of 2â¯d (influent ratios of W:Mo:acetate of 0.5:1.0:24â¯mM). The final concentrations of these conditions were sufficient to meet national wastewater discharge standards. In the controls with individual metals or acetate, lower contaminant removals were obtained (W, 2 â 4%; Mo, 3 â 5%, acetate, 36 â 39%). Metals removal in all cases was primarily due to the biocathodes rather than the bioanodes. The presence of metals decreased microbial diversity on the anodes and increased diversity on the cathodes, based on analysis at the phylum, class and genus levels, as a function of HRT and influent concentration. This study demonstrated the feasibility of larger-scale single-chamber MECs for efficient treatment of W and Mo, moving metallurgical MECs closer to commercialization for wastewater treatment of these two metals.
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Fuentes de Energía Bioeléctrica , Molibdeno , Acetatos , Electrodos , Electrólisis , Hidrógeno , TungstenoRESUMEN
2-Deoxy-d-glucose (2DG), a glucose analog that inhibits glycolysis, has acute and chronic antiepileptic effects. We evaluated 2DG's acute effects on synaptic and membrane properties of CA3 pyramidal neurons in vitro. 2DG (10 mM) had no effects on spontaneously occurring postsynaptic currents (PSCs) in 3.5 mM extracellular potassium concentration ([K+]o). In 7.5 mM [K+]o, 2DG significantly reduced the frequency of epileptiform bursting and the charge carried by postsynaptic currents (PSCs) with a greater effect on inward excitatory compared with outward inhibitory charge (71% vs. 40%). In 7.5 mM [K+]o and bicuculline, 2DG reduced significantly the excitatory charge by 67% and decreased the frequency but not amplitude of excitatory PSCs between bursts. In 7.5 mM [K+]o, 2DG reduced pharmacologically isolated inhibitory PSC frequency without a change in amplitude. The frequency but not amplitude of inward miniature PSCs was reduced when 2DG was applied in 7.5 mM [K+]o before bath application of TTX, but there was no effect when 2DG was applied after TTX, indicating a use-dependent uptake of 2DG was required for its actions at a presynaptic locus. 2DG did not alter membrane properties of CA3 neurons except for reducing the slow afterhyperpolarization in 3.5 but not 7.5 mM [K+]o. The reduction in frequency of spontaneous and inward miniature PSCs in elevated [K+]o indicates a presynaptic mechanism of action. 2DG effects required use-dependent uptake and suggest an important role for glycolysis in neuronal metabolism and energetics in states of high neural activity as occur during abnormal network synchronization and seizures. NEW & NOTEWORTHY 2-Deoxy-d-glucose (2DG) is a glycolytic inhibitor and suppresses epileptiform activity acutely and has chronic antiepileptic effects. The mechanisms of the acute effects are not well delineated. In this study, we show 2DG suppressed abnormal network epileptiform activity without effecting normal synaptic network activity or membrane properties. The effects appear to be use dependent and have a presynaptic locus of action. Inhibition of glycolysis is a novel presynaptic mechanism to limit abnormal neuronal network activity and seizures.
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Región CA3 Hipocampal/metabolismo , Desoxiglucosa/farmacología , Epilepsia/metabolismo , Neuronas/metabolismo , Potenciales Sinápticos , Animales , Bicuculina/farmacología , Región CA3 Hipocampal/citología , Región CA3 Hipocampal/fisiología , Epilepsia/fisiopatología , Glucólisis , Neuronas/efectos de los fármacos , Neuronas/fisiología , Potasio/farmacología , Ratas , Ratas Sprague-Dawley , Tetrodotoxina/farmacologíaRESUMEN
Present here is a new dual ratiometric luminescent probe D which is a trichromatic and white-light-emitting metal-organic framework (MOF) composite facilely obtained by incorporating red/green-emitting complex modules into a blue-emitting MOF. Probe D exhibits remarkable capabilities of sensing different volatile organic solvents (VOSs) via 2D code recognition of the two VOS-dependent MOF ligand-to-module ratios of the emission-peak intensities. For specific VOSs, the resultant luminescent color changes from the starting white color are sharp enough to be visible to the naked eye. Remarkably, D can differentiate solution-phase nitroaromatics and metal ions by recording the evolution of the two ratios during titration processes, enabling an unusual 3D code recognition using the titrant amount as the third dimension for the first time. D also can be used to detect dinoseb, Fe3+ and Al3+ ions quantitatively by analysis of the ratios with detection limits as low as 0.050, 0.41, and 0.12â ppm, respectively. Clearly, such a self-referencing trichromatic probe can maximize the output information and significantly enhance the detection selectivity and sensitivity via multi-dimensional sensing, and has great potentials for practical applications.
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OBJECTIVE: To observe the clinical efficacy of acupuncture combined with western medicine in the treatment of rheumatoid arthritis (RA) and its effect on blood stasis, and to explore ways to improve the clinical curative effect. METHODS: A total of 56 patients of RA were randomly divided into an observation group and a control group, 28 cases in each one. â ibuprofen sustained-release tablets, 2 times a day, each time 0.3 g; â¡ methotrexate tablets (MTX), once a week, each time 10 mg ⢠folic acid tablets, once a week, each time 5 mg were given in the control group, 30 days as one course, a total of 3 courses were required. In the observation group, acupuncture was adopted on the basis of the treatment as the control group. The main acupoints were Ganshu (BL 18), Pishu (BL 20), Shenshu (BL 23), Hegu (LI 4), Quchi (LI 11), Zusanli (ST 36) combined with local ashi points. The treatment was given once every day for continuous 6 days a week, the treatment for 30 days as one course, a total of 3 courses were required. The serological indexs were evaluated before and after treatment, including the rheumatoid factor (RF), hypersensitive C-reactive protein (hs-CRP), erythrocyte sedirnentation rate (ESR), platelet (PLT), fibrinogen (FBG) and D-dimer (D-D), the changes of disease activity score (DAS-28), symptom grade quantitative score, blood stasis syndrome symptom (the joint tingling, lip color, tongue, pulse, subcutaneous ecchymosis, squamous and dry skin) score were observed. RESULTS: â The scores of RF, hs-CRP, ESR, PLT, D-D, FBG, DAS-28 and symptom grade quantitative were significantly improved in the two groups compared with those before treatment (all P<0.05), and the scores of hs-CRP, ESR, DAS-28 and symptom grading in the observation group were more better than those in the control group (all P<0.05). â¡ The total score of joint tingling, lip color, tongue, pulse, subcutaneous ecchymosis, squamous and dry skin and blood stasis syndrome in both groups were decreased after treatment (all P<0.05), the joint tingling, tongue, lip color and subcutaneous ecchymosis were improved obviously in the observation group than those in the control group (all P<0.05). ⢠The total effective rate in the observation group was 85.7% (24/28), which was better than 75.0% (21/28) in the control group (P<0.05). CONCLUSION: Acupuncture combined with western medicine can not only improve the clinical efficacy of RA patients but also improve the blood stasis.
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Terapia por Acupuntura , Artritis Reumatoide/terapia , Puntos de Acupuntura , Terapia Combinada , Ácido Fólico/uso terapéutico , Humanos , Ibuprofeno/uso terapéutico , Metotrexato/uso terapéutico , Resultado del TratamientoRESUMEN
The deposition and separation of W and Mo from aqueous solutions with simultaneous hydrogen production was investigated in stacked bioelectrochemical systems (BESs) composed of microbial electrolysis cell (1#) serially connected with parallel connected microbial fuel cell (2#). The impact of W/Mo molar ratio (in the range 0.01â¯mM : 1â¯mM and vice-versa), initial pH (1.5 to 4.0) and cathode material (stainless steel mesh (SSM), carbon rod (CR) and titanium sheet (TS)) on the BES performance was systematically investigated. The concentration of Mo(VI) was more influential than W(VI) in determining the rate of deposition of both metals and the rate of hydrogen production. Complete metal recovery was achieved at equimolar W/Mo ratio of 0.05â¯mM : 0.05â¯mM. The rates of metal deposition and hydrogen production increased at acidic pH, with the fastest rates at pH 1.5. The morphology of the metal deposits and the valence of the Mo were correlated with W/Mo ratio and pH. CR cathodes (2#) coupled with SSM cathodes (1#) achieved a significant rate of hydrogen production (0.82⯱â¯0.04â¯m3/m3/d) with W and Mo deposition (0.049⯱â¯0.003â¯mmol/L/h and 0.140⯱â¯0.004â¯mmol/L/h (1#); 0.025⯱â¯0.001â¯mmol/L/h and 0.090⯱â¯0.006â¯mmol/L/h (2#)).
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Molibdeno/química , Tungsteno/química , Fuentes de Energía Bioeléctrica , Electroquímica , Electrodos , Hidrógeno , Concentración de Iones de Hidrógeno , SolucionesRESUMEN
A self-driven microbial fuel cell (MFC) - microbial electrolysis cell (MEC) system, where electricity generated from MFCs is in situ utilized for powering MECs, has been previously reported for recovering Cr(VI), Cu(II) and Cd(II) with individual metals fed in different units of the system in batch operation. Here it was advanced with treating synthetic mixed metals' solution at appropriately adjusting composites in fed-batch and continuous flow operations for complete separation of Cr(VI), Cu(II) and Cd(II) from each other. Under an optimal condition of hydraulic residence time of 4â h, matching of two serially connected MFCs with one MEC, and fed with a composite of either 5â mgâ L-1 Cr(VI), 1â mgâ L-1 Cu(II) and 5â mgâ L-1 Cd(II), or 1â mgâ L-1 Cr(VI), 5â mgâ L-1 Cu(II) and 5â mgâ L-1 Cd(II), the self-driven MFC-MEC system can completely and sequentially recover Cu(II), Cr(VI) and Cd(II) from mixed metals. This study provides a true sustainable and zero-energy-consumed approach of using bioelectrochemical systems for completely recovering and separating Cr(VI), Cu(II) and Cd(II) from each other or from wastes or contaminated sites.
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Fuentes de Energía Bioeléctrica , Cadmio/química , Cromo/química , Cobre/química , Contaminantes Químicos del Agua/química , Electrólisis , Acetato de Sodio/química , Acetato de Sodio/metabolismoRESUMEN
The role of Fe(III) was investigated as an electron-shuttle mediator to enhance the reduction rate of the toxic heavy metal hexavalent chromium (Cr(VI)) in wastewaters, using microbial fuel cells (MFCs). The direct reduction of chromate (CrO4-) and dichromate (Cr2O72-) anions in MFCs was hampered by the electrical repulsion between the negatively charged cathode and Cr(VI) functional groups. In contrast, in the presence of Fe(III), the conversion of Cr(VI) and the cathodic coulombic efficiency in the MFCs were 65.6% and 81.7%, respectively, 1.6 times and 1.4 folds as those recorded in the absence of Fe(III). Multiple analytical approaches, including linear sweep voltammetry, Tafel plot, cyclic voltammetry, electrochemical impedance spectroscopy and kinetic calculations demonstrated that the complete reduction of Cr(VI) occurred through an indirect mechanism mediated by Fe(III). The direct reduction of Cr(VI) with cathode electrons in the presence of Fe(III) was insignificant. Fe(III) played a critical role in decreasing both the diffusional resistance of Cr(VI) species and the overpotential for Cr(VI) reduction. This study demonstrated that the reduction of Cr(VI) in MFCs was effective in the presence of Fe(III), providing an alternative and environmentally benign approach for efficient remediation of Cr(VI) contaminated sites with simultaneous production of renewable energy.
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Fuentes de Energía Bioeléctrica , Cromo/química , Electrones , Hierro/química , Algoritmos , Difusión , Electroquímica , Electrodos , Oxidación-Reducción , Aguas Residuales/análisisRESUMEN
Bioelectrochemical systems (BESs) were first operated in microbial fuel cell mode for recovering Cu(II), and then shifted to microbial electrolysis cells for Cd(II) reduction on the same cathodes of titanium sheet (TS), nickel foam (NF) or carbon cloth (CC). Cu(II) reduction was similar to all materials (4.79-4.88mg/Lh) whereas CC exhibited the best Cd(II) reduction (5.86±0.25mg/Lh) and hydrogen evolution (0.35±0.07m(3)/m(3)d), followed by TS (5.27±0.43mg/Lh and 0.15±0.02m(3)/m(3)d) and NF (4.96±0.48mg/Lh and 0.80±0.07m(3)/m(3)d). These values were higher than no copper controls by factors of 2.0 and 5.0 (TS), 4.2 and 2.0 (NF), and 1.8 and 7.0 (CC). These results demonstrated cooperative cathode electrode and in situ deposited copper for subsequent enhanced Cd(II) reduction and hydrogen production in BESs, providing an alternative approach for efficiently remediating Cu(II) and Cd(II) co-contamination with simultaneous hydrogen production.
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Fuentes de Energía Bioeléctrica , Cadmio/química , Cobre/química , Electrólisis/métodos , Hidrógeno/química , Aniones , Cloruros/química , Electrodos , Concentración de Iones de Hidrógeno , Níquel , Sulfatos/química , TemperaturaRESUMEN
OBJECTIVE: To explore the effect of Xinfeng Capsule (XC) on lipoprotein metabolism of rheumatoid arthritis (RA) patients. METHODS: Totally 180 RA patients were assigned to the experimental group and the control group by random digit table, 90 in each group. Patients in the experimental group took XC (three pills each time, three times daily), while those in the control group took Methotrexate Tablet (four tablets each time, once per week). One month consisted of one therapeutic course and all patients were treated for two therapeutic courses. A healthy control group consisting of 60 patients was also set up. Changes of lipoprotein indices, clinical efficacy, lipid metabolism, joint symptoms and signs, activity indicators were observed, and correlation analyses were performed. RESULTS: Compared with the healthy control group, expression levels of prealbumin (PA), globulin (GLO), high-density lipoprotein (HDL), apolipoprotein Al (Apo-A1) were lowered in RA patients (P <0. 05, P <0. 01). Correlation analyses showed that PA was negatively correlated with joint tenderness, morning stiffness time, disease activity score (DAS-28), C-reactive protein (CRP), interleukin (IL)-6, respectively. Total protein (TP) was negatively correlated with joint tenderness. GLO was negatively correlated with joint tenderness and DAS-28. HDL was negatively correlated with erythrocyte sedimentation rate (ESR) and endothelin (ET)-1. Apo-Al was negatively correlated with joint pain; Apo-B was negatively correlated with CRP; LDL was negatively correlated with morning stiffness time (P <0. 05, P <0. 01). Compared with before treatment, expression levels of PA, HDL, Apo-A1 , Apo-B, and serum IL-10 contents increased, and expression levels of ESR, CRP, IL-6, ET-1 , joint pain, joint swelling, morning stiffness time, and DAS-28 decreased in the experimental group (P <0. 05, P <0. 01). PA increased more after treatment than before treatment in the control group (P <0. 01). There was statistical difference in joint symptoms (except joint tenderness) and activity indices (except ET-1) in the control group (P <0. 05, P <0. 01). Compared with the control group after treatment, PA and HDL increased, ET-1 and duration of morning stiffness decreased in the experimental group (all P <0. 05). CONCLUSIONS: Lipoprotein metabolic disorder exists in RA patients, and it is associated with disease activity. XC could obviously improve lipoprotein metabolism and joint symptoms.
Asunto(s)
Artritis Reumatoide/metabolismo , Medicamentos Herbarios Chinos/farmacología , Lipoproteínas HDL/metabolismo , Artritis Reumatoide/tratamiento farmacológico , Sedimentación Sanguínea , Proteína C-Reactiva , Cápsulas , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Interleucina-10 , Interleucina-6 , Lipoproteínas , MetotrexatoRESUMEN
Angiogenesis is crucial for cancer growth and metastasis. T cells are also key members of the adaptive immunity against tumorigenesis. The aim of the present study was to observe the effects of Feijining Decoction (FJND) on vascular endothelial growth factor (VEGF) protein expression and T cell subsets [cluster of differentiation 4+(CD4+) and CD8+ T lymphocyte] in Lewis lung carcinoma (LLC)-bearing mice. C57BL/6J mice were subcutaneously implanted with LLC cells. Forty carcinoma-bearing mice were randomly assigned to four groups (10 animals/group). The control group (CG) were the untreated group, the cisplatinum (DDP) group (DG) mice were treated with DDP, the FJND group (FG) were treated with FJND and the FJND + DDP group (FDG) were treated with FJND and DDP. Western blot and flow cytometry were used to evaluate the VEGF protein expression of tumor tissue and T cell subsets of the spleen. Spontaneous activity in 5 min was observed by the photoelectric counting method. DDP + FJND (FDG group) markedly inhibited tumor growth compared to the DG mice. The protein expression of VEGF was significantly downregulated in the carcinoma of FG mice compared to CG mice. VEGF protein expression was significantly reduced in FDG compared to DG mice. In the FG mice, the splenic CD4+ and CD4+/CD8+ cells were significantly increased compared to the CG mice, and the splenic CD4+ cells in the FDG mice were significantly increased compared to the DG group. In conclusion, FJND can inhibit tumor growth by downregulating VEGF protein expression and improving the immune function.